Zeppelin Design Labs PERCOLATOR Assembly Instructions

THE PERCOLATOR

Assembly Instructions

2

WATT TUBE AMPLIFIER KIT

ZEPPELINDESIGNLABS.COM • 2950 N. WESTERN, CHICAGO, IL 60618

THE PERCOLATOR

2 Watt Tube Amplifier Kit Assembly Instructions

INTRODUCTION ...................................................................................................... 3

CAUTIONS, WARNINGS, DANGERS ......................................................................... 3

BUILDING THE AMPLIFIER .......................................................................................... 5

WHAT YOU WILL NEED ......................................................................................... 5

WHAT’S IN THE BOX ............................................................................................. 6

POPULATING THE PRINTED CIRCUIT BOARD .......................................................... 10

LOADING THE CHASSIS ...................................................................................... 22

TESTING THE AMP .............................................................................................. 36

ASSEMBLING THE CHASSIS ................................................................................. 41

BUILDING THE CABINET ......................................................................................... 42

WHAT YOU WILL NEED ....................................................................................... 42

A WORD ON COUNTERSINKS ............................................................................ 43

ASSEMBLING THE BOX ........................................................................................ 44

FINISHING THE BOX ........................................................................................... 54

ASSEMBLING THE CABINET ................................................................................. 58

ASSEMBLING THE GRILL ....................................................................................... 59

COMPLETING THE HEAD ........................................................................................ 67

INSTALLING THE AMP .......................................................................................... 67

INSTALLING THE GRILL ......................................................................................... 68

USING YOUR NEW HEAD ...................................................................................... 69

CABINET TEMPLATES .............................................................................................. 70

© 2015 ZEPPELIN DESIGN LABS. NO PART OF THIS DOCUMENT MAY BE REPRODUCED WITHOUT WRITTEN PERMISSION FROM THE

AUTHOR. ZEPPELIN DESIGN LABS TAKES NO RESPONSIBILITY FOR ANY DAMAGE OR HARM THAT MAY COME TO ANYONE OR

ANYTHING THROUGH THEIR PRODUCTS.

2

INTRODUCTION

Thanks for buying the Percolator single-tube, 2-watt guitar amplifier kit from Zeppelin Design Labs! We
hope you will have fun assembling this kit, followed by many years of musical enjoyment. We think
we’ve produced a pretty nice product, and we’d love to hear your feedback. Send an email, or post
on the ZDL forum.

Note there is a serial number sticker on the chassis. Reference this serial number when and if you ever
need to contact us for assistance.

The Percolator was designed around a single tube developed by GE in the early 1960’s under the
brand name “Compactron.” Compactron tubes have multiple amplifier sections in one bottle. The tube
in the Percolator has two triodes and one sharp cut-off pentode. That’s the same topology as the Fender
Champ, but in one bottle! This tube was never intended to be used in an audio circuit (it was originally
designed for use in various parts of a TV circuit), but it works and sounds great in a guitar amplifier.
Since this tube is rarely, if ever, seen in guitar amps, it offers a rather unique tone.

Compactrons were developed in a time of fast technological growth. In the early 1960’s transistors were
becoming more stable and practical for use in more demanding circuits. They also were much smaller
and didn’t require as much power (via heating filaments). The tube market was being challenged and
threatened by this new solid state competitor. The GE corporation (which was one of, if not the most
prolific tube developers in the world at the time) was well invested in their miniature tube line and
wasn’t too interested in making the transition to transistor development. So to compete with transistors
and give tubes a few more years in the market, the engineers at GE developed the Compactron that
could take the place of several tubes with just one bottle. It was the tube equivalent to the integrated
circuit. They were mostly designed for use in the color TV market, but some of them did find their way
into radios and hifi amps. Ampeg even used a Compactron in some of their preamp circuits. GE made
a big push to promote and use these tubes in their products, but eventually transistors did win the
technology battle and tubes were altogether replaced in televisions, leaving large stockpiles of unused
Compactrons in warehouses. The last Compactrons were made in the early 1990’s and are still readily
available today as “new old stock” (NOS) items. The Percolator, with its single Compactron tube, gives
us a chance to re-purpose a piece of tube history, while offering unique tonality in this modern market.

CAUTIONS, WARNINGS, DANGERS

This is not a beginner’s electronics project! If you have not worked with line/high voltage electricity
before do not attempt this project without qualified help. THIS THING CAN KILL YOU if you don’t know
what you are doing. We expect that you know how to safely and properly solder electronics. If you
have never soldered a circuit board before, you MUST practice on something simpler and safer! If you
lack experience, build this kit with a qualified friend. Use common sense when soldering. Use safety
glasses and don’t burn yourself or anything else. We also expect you to know how to use a digital
multimeter (DMM). If you are not comfortable with using a DMM, either have an experienced friend
help you, or learn how by watching some YouTube videos on using a multimeter.

3

There are two versions of power transformers that are available for the Percolator: The domestic
118V/60hz transformer for use in places that have 120V/60Hz wall power, and the international
230V/50Hz transformer for use in places that have 220V-240V/50Hz wall power. If you do not have
the proper power transformer for the type of wall power you have available then you must use an
external conversion transformer.

Amplifiers handle HIGH VOLTAGES, higher than what comes out of the wall outlet. If you do not know
what you are doing or you screw up this project, you could expose yourself or others to DEADLY HIGH
VOLTAGE! Amplifiers have devices in them called capacitors. Capacitors (or caps) store high-voltage
electricity for a long time, hours after the unit is turned off. If you do not know what you are doing,
and you handle the capacitors recklessly, YOU COULD KILL YOURSELF OR THE GUY NEXT TO YOU!

Zeppelin Design Labs LLC takes no responsibility for any harm that may come to anyone or anything
through this product.

This instruction guide is full of CAUTIONS, WARNINGS, and DANGERS. These are actually three
distinct things:

1. CAUTION indicates a potentially hazardous situation that, if not avoided, could result in minor

or moderate injury, like cutting or burning your finger.

2. WARNING indicates a potentially hazardous situation that, if not avoided, could result in death

or serious injury, like shocking yourself at a wall receptacle.

3. DANGER indicates an imminently hazardous situation that, if not avoided, will result in death

or serious injury. This word is limited to use in the most extreme situations.

Once your amp is complete and safely installed in its cabinet, it is no more dangerous than a toaster.
There is a warning label on the chassis reminding you and others of the hazards typical to any electric
appliance; but while under construction, with the chassis open and the components exposed, this
manual contains the warnings you need to stay safe!

BUILDING THE AMPLIFIER

WHAT YOU WILL NEED

To build your Percolator, you will need the following:

1. Tools

• Digital Multimeter, able to measure DC voltage, AC voltage, and Resistance

• Screw Drivers

• #1 Phillips

• #2 Phillips

• #2 Phillips, with a short shaft

• Small Straight

• Ruler, 6” or 12”, with markings at least to the 1/8”

• A small awl, or metal poking probe

• Soldering Iron (not a soldering gun, or a “cold heat” iron), good quality, 15-50 watt, with

a good medium or small sized tip, conical or “screwdriver” shape. One with a temperature

4

control and a stand is best.

• Damp sponge or dry solder-cleaning pad

• Wire stripper, to strip 18-gauge stranded and 20-gauge solid core wire

• Flush cutters or small diagonal cutters

• Needle-nose pliers

• X-Acto knife, or razor blade

• Solder sucker or solder braid – optional, but very handy if you have to remove / repair any

components!

2. Supplies

• Solder, 60/40 rosin core, the smaller diameter the better (we prefer .031” or .80mm diameter).
Make sure it’s good quality; we prefer Kester brand, but the Radio Shack brand will work fine.

• Isopropyl alcohol, denatured alcohol, or rubbing alcohol

3. Percolator Kit (duh)

WHAT’S IN THE BOX

Table 1: Percolator Bill Of Materials (BOM) is a complete parts
list of everything that should be present in your kit, followed by
photos of each part. Print the BOM and carefully go through the
kit, identifying every part. Note that some of the components are
difficult to tell apart. Compare them carefully with the photos.
Besides verifying that nothing is missing, this will acquaint you

cookie sheet or into a big fruit

bowl, NOT onto the cluttered

workbench, or onto the living room

carpet! This will protect you from

TIP: Empty the

parts of the kit onto a

losing tiny parts.

with the parts and their names. If ANYTHING is missing, first
double-check: we double-checked before sealing the box at our lab! If
it’s still missing, EMAIL US right away at [e-mail]. Include your serial number
(given via a sticker on the chassis) in your email. If we are reasonably convinced that we goofed and
shorted your kit, we will get replacement parts in the mail to you as soon as possible. If you lose or
damage anything, we will be glad to sell you replacements. The unusual or custom components can
be ordered directly from us (contact [e-mail]). For more common parts, like
resistors, caps, or screws, you may just want to go to a local electronics or hardware store.

Figure 1: What’s In The Box?

5

Table 1: Percolator Bill Of Materials

Loose in the box:

Part # Description Notes Qty

CA05.1 Cabinet Top/Bottom Longer

CA05.2 Cabinet Side Shorter

CB03 Power Cable IEC 6’

CH03.1 Chassis Top

CH03.2 Chassis Base Plate

GC02 Grill Cloth Black/Silver/Beige

GF02.1 Grill Frame Top/Bottom Longer

GF02.2 Grill Frame Side Shorter

HA12 Aluminum Handle 5-3/4” / 96mm

PC23 PCB Printed Circuit Board 1

PL11 Percolator Face Label

J3 Power Receptacle w/ Fuse

T1 Power Transformer

T2 Output Transformer 4W

V1 Vacuum Tube NOS Compactron

2
2
1
1
1
1
2
2
1

1
1
1
1
1

CA05.1 CA05.2 CB03 CH03.1 CH03.2

GC02 GF02.1 GF02.2 HA12 PC23

PL11 J3 T1 T2 V1

6

In the Components bag:

Part # Description Notes Qty

CB10.1 10.5cm Hookup Wire 20/1 Feedback loop

CB10.2 10.5cm twisted pair Hookup Wire 20/1 Heater voltage

CB10.3 4cm Hookup Wire 20/1 Ground

CB10.4 6cm Hookup Wire 20/1

C9, C10, C11 Electrolytic Capacitor 100uF/250V

C2, C5, C8, C12 Electrolytic Capacitor 100uF/16V

C1, C3, C6 Film Capacitor 0.022uF/250V

C4, C7 Ceramic Disc Capacitor 470pF/50V

BR1, BR2 Bridge Rectifier 2A/1000V

F1 Fuse 1A 250V

J1 ¼” Stereo Jack (w/ plastic nut) Input (Plastic barrel)

J2 ¼” Mono Jack (w/ metal nut and washer) Output (Metal barrel)

KN05 Knob

D1 Red LED 5mm

VR1 Potentiometer 100KA

R1, R6, R11 Resistor 22K Red, Red, Orange, Gold

R5, R9, R10 Resistor 220K Red, Red, Yellow, Gold

R3, R8 Resistor 47K Yellow, Violet, Orange, Gold

R4 Resistor 820R

R7, R14, R17 Resistor 1.5K (or 1K5) Brown, Green, Red, Gold

R16 Resistor 4.7K (or 4K7) Yellow, Violet, Red, Gold

R2 Resistor 1M Brown, Black, Green, Gold

R15, R12 Metal Film Resistor 120R 1% Brown, Red, Black, Black, Brown

R13 Metal Film Resistor 2.2K (or 2K2) 1%

SK05 Panel Mount LED Bezel

SK10 12 Pin Tube Socket

S1 SPDT Toggle Switch PCB Mount

Output jumper

Gray, Red, Brown, Gold

Red, Red, Black, Brown, Brown

1
1
2
1
3
4
3
2
2
1
1
1
1
1
1
3
3
2
1
3
1
1
2
1
1
1
1

CB10.1 CB10.2 CB10.3 CB10.4 C9, C10, C11

7

C2, C5, C8, C12 C1, C3, C6 C4, C7 BR1, BR2 F1

J1 J2 KN05 D1 VR1

R1, R6, R11 R5, R9, R10 R3, R8 R4 R7, R14, R17

R16 R2 R15, R12 R13 SK05

SK10 S1

In the Hardware bag:

Part # Description Notes Qty

CB20 Solder Lug

CH05 Isolation Fin

FT03 Foot 1/2”x1/4”

GR02 Rubber Grommet

NU10 Keps Lock Nut M3

SC38 Philips Machine Screw – Pan head M3x6

SC61 Philips Wood Screw - Flat head 6x1-1/4”

1
2
4
4

5
17
11

8

SC63 Philips Sheet Metal Screw - Pan head 8x1/2” Assembling the chassis

SC66 Philips Sheet Metal Screw - Pan head 6x5/8” Attaching the feet

SC67 Philips Sheet Metal Screw - Flat head 6x1” Installing the chassis in the cabinet

SC68 Philips Sheet Metal Screw - Pan head 10x3/8 Attaching the fins

SP11 Nylon Hex Standoff M3x12

WA07 Lock Washer M3

CB20 CH05 FT03 GR02 NU10

SC38 SC61 SC63 SC66 SC67

4
4
4
4
6
6

SC68 SP11 WA07

POPULATING THE PRINTED CIRCUIT BOARD

Your workspace should be well-lit, well-ventilated, and disposable; that is, don’t work on the nice
dining room table! Work on a utility surface that you can burn, drill and scratch. A piece of ¼”
tempered masonite, or a chunk of MDF, makes an excellent cover if you don’t have a utility work bench.

CAUTION: Solder fumes are not healthy for you. The fumes consist of vaporized flux, which

can irritate your nose, lungs, and even your skin. You MUST work in a space where the air
drifts away from you as you work, so fumes do not rise straight onto your face.

CAUTION: Solder residue usually contains lead, which is poisonous if you ingest it. Do not

breathe the fumes, do not eat the supplies, wash your hands after you handle solder, and
sweep and wipe up your work space after EVERY USE.

The printed circuit board (PCB) holds most of the components in this amp. Nearly all of the components

9

will be installed on the “component side” of the board, which is the side that has the Zeppelin Design
Labs logo on it. The other side of the board is called the “solder side”, which, as the name implies, is
the side on which the legs of the components are soldered to the board. Proper technique for installing
and soldering components to a circuit board is demonstrated in our assembly reference video, but
there are several other great resources on YouTube under the search “soldering tutorial.” The general
procedure consists of the following:

1. Install the part on the “component side” of the board, by threading the wire leads through
the appropriate holes in the board. For your convenience, the board has silk screen outlines
indicating where the components should be placed, along with text indicating the part number
and often times the component value.

2. Hold the component in place with your finger and turn the board over.

3. Gently bend the leads out at about 45 degrees to keep the component from falling out of its
holes.

4. Install all of one type of component, bending each of the leads as they are installed.

5. Flip the board over solder-side-up, and solder all of the components in one pass.

6. Clip the leads off (with small diagonal cutters) right at the solder joint.

Let’s begin!

1. Standoffs (Part # SP11): Use 6 standoffs, 6 M3 screws (Part # SC38), and 6 lock washers (Part
# WA07). The plastic standoffs are installed on the solder side of the board, which means they
are screwed in from the component side. The lock washer goes between the PCB and the standoff
(not between the screw head and the PCB)1. Place the 6 standoffs in the locations indicated
below2.

1 2

2. Resistors: The value of resistors are given by a series of colored stripes on their body. There are
several tutorials on line describing how to decode these stripes, but we will identify each resistor
for you by simply naming the stripe colors, and giving you the value and the part number. Figure
2: Component Values and Locations on the next page is a handy reference. If you are color blind
or can’t see the stripes clearly, then you must use your digital multimeter to measure the resistance
of each resistor.

3. The hole spacing of most of the resistors on the circuit board allows the leads to be (gently) bent

10

90 degrees at the body of the resistor3. This allows most resistors to slip into their holes very easily.
Resistors R13 & R17 are exceptions to the normal hole spacing, so for those two components
you’ll have to estimate where to bend the leads.

3

Figure 2: Component Values and Locations

a. Start with the 22K resistors (R1, R6, R11), labeled RED, RED, ORANGE, GOLD. Compare to

its picture in the BOM. Find their locations on the circuit board and install and bend the leads
as described above
the leads to keep them in their place.

4 5

4,5

. Don’t solder any of them until all 17 resistors are installed; just bend

11

b. Continue with the 220K resistors (R5, R9, R10), labeled RED, RED, YELLOW, GOLD.
c. Continue with the 1.5K (or 1K5) resistors (R7, R14, R17), labeled BROWN, GREEN, RED,

GOLD. R17 has a larger lead spacing than most of the other resistors so estimate where to

bend the leads.
d. Continue with the 47K resistors (R3, R8), labeled YELLOW, VIOLET, ORANGE, GOLD.
e. Continue with the 120 ohm (or 120R) resistors (R12, R15), which are blue in color and are

labeled BROWN, RED, BLACK, BLACK, BROWN.
f. Continue with the 2.2K (or 2K2) resistor (R13), which is also blue in color and is labeled RED,

RED, BLACK, BROWN, BROWN. The lead spacing on R13 is also abnormal, so bend the

leads the proper length to fit into their holes.6

6

g. Continue with the 1M resistor (R2), labeled BROWN, BLACK, GREEN, GOLD.
h. Continue with the 820 ohm (or 820R) resistor (R4), labeled GRAY, RED, BROWN, GOLD.
i. Last, install the 4.7K (or 4K7) resistor (R16), labeled YELLOW, VIOLET, RED, GOLD.
j. You should have a whole forest of bent leads coming out the solder side of the board.7 Now

you can turn the board solder-side-up and solder each one to the board.8

7 8

k. Now clip each lead with your flush cutters at the solder joint.

9

l. Before installing any more components on the circuit board, double check the resistance values

of each of the installed resistors. Set your digital multimeter to the “ohms” or “resistance”

setting, and measure across all of the resistors. Compare the measured value to the listed

value in Figure 2 on the previous page.10 Make sure they are all correct (within 5%) before

moving on!

12

9 10

4. Capacitors: The Percolator uses 3 different types of capacitors: Film capacitors, tiny ceramic disc
capacitors, and electrolytic capacitors. Film and ceramic caps can be installed in either direction
on the circuit board (the legs can be reversed in their holes). But electrolytic caps are polarized,
meaning they will only work when they are installed in the correct orientation.

a. Let’s start with the two tiny ceramic caps (C4 ,C7).11 Install, solder and clip the leads.

11

b. Continue with the three film caps (C1 ,C3 ,C6).12 Install13, solder and clip the leads.

12 13

c. Now for the tricky electrolytic caps. Note all the electrolytic capacitors have one leg that is

longer than the other.

14, 15

The longer leg is the positive side of the cap. The positive leg (the
longer leg) goes in the square pad. PAY CLOSE ATTENTION TO THIS WHEN YOU ARE
INSTALLING THESE CAPS! It is very easy to install one or more electrolytic caps backwards!
If you do, the amp won’t work correctly! Double check Figure 2 for reference. Figure 2 also

13

has “+” signs where the positive (longer) lead goes. The negative side of the caps have white
stripes pointing to the negative lead.

14 15

d. Install all of the smaller electrolytic caps (C2 ,C5 ,C8 ,C12). Solder and clip the leads.16

16

e. Now install the three big electrolytic caps (C9 ,C10 ,C11).17 Solder and clip the leads18, but

put one of these clipped leads aside for use in the next step.

17 18

WARNING: The big electrolytic caps (C9 ,C10 ,C11) are likely to explode if they are installed

backwards, which could result in personal injury. Install in STRICT CONFORMANCE with
these instructions!

f. Before moving on, double check the orientation of each of the electrolytic caps. Make sure the

stripe on each electrolytic cap is in the same direction as each cap in the picture.19

14

19

5. Jumper wire: Use one of the leads that you just clipped off of the big electrolytic capacitors (C9,
C10, or C11) as this jumper. Use your needle nose pliers to bend the lead in the shape of a
staple.20 Install the jumper in the holes and solder the leads.

21

20 21

6. Bridge rectifiers (Part # BR1, BR2): Bridge rectifiers have 4 leads and it is very important to make
sure each lead goes in the correct hole. The only indication on the circuit board of how the
rectifiers should be oriented is a square pad. The positive lead (the longest lead22, labeled with a
“+”) goes in the square hole23. The other leads should line up properly with the other holes.

22 23

a. Install both BR1 and BR2 with this orientation. Solder and clip the leads.
b. Before moving on, double check the orientation of the bridge rectifiers. Make sure the “+”

and “-” printed on the component are in the same orientation as the “+” and “-” on the circuit

24

board.

15

24

7. Input jack (Part # J1): Remove the plastic nut from the input jack and put it aside until the next
section. Snap the input jack into its holes on the circuit board.25 Make sure you solder the leads
well.26 The leads are too short to cut on this component so don’t bother.

25 26

8. Potentiometer (Part # VR1): Remove the nut and washer from the shaft of the pot and put them
aside until the next section. Install the potentiometer (“pot” for short) with the shaft facing away
from the board. The leads are too short to bend out, so you just have to hold the pot while you
solder at least one lead.27 It is very important to make sure all the leads are completely seated in
their holes before soldering, otherwise the board won’t fit into the chassis properly. The leads are
too short to cut on this component too.

27

9. Power switch (Part # S1): Carefully install the power switch on the PCB.28 If all the leads don’t line
up right away, very gently guide them into the holes with your needle-nose pliers.29 When you
solder the switch, it is very important to make sure all the leads are making good connections with

16

the board because this component is switching high voltage. The front two pins just act as anchors
for the switch and are connected to the large piece of metal on the front of the component. Extra
heat may be needed to secure these pins properly because the large piece of metal tends to act
as a heat sink.

28 29

Once you have soldered all the leads, check the rigidity of the solder joints by flipping the switch
several times. Make sure it feels secure.

10. LED (Part # D1): The LED (light emitting diode) is a polarized component, meaning that it matters
which way it goes into the holes. Following the standard of all the polarized components on this
board, the long lead goes into the square hole.

30, 31

If you do not install the LED in the correct
orientation the “on light” will not work. Install the LED in the holes so that the top of the LED stands
about 7/8” (23mm) off the surface of the board.32 Solder the LED on the component side of the
board (it will be easier to switch later if you get it backwards).33 Clip the leads on the solder side
of the board.

30 31

32 33

17

11. Feedback loop wire (Part # CB10.1): Strip about 1/4” (6mm) of insulation from each end of the

10.5cm single stranded hookup wire.34 Solder one end of this wire to the FBL hole so the wire is
emerging from the component side of the board.

35, 36

The other end of the wire will be used in the

next section.

34 35

36

12. 6cm Hookup wire (Part # CB10.4): Strip about 1/8” (3-4mm) of insulation from each end of the
6cm hookup wire. With your pliers bend both ends at a right angle.37 This wire goes on the solder
side of the board, so flip the board over and install the wire where it goes (note the picture38).
Solder it on the component side of the board.

39

Now bend the wire along the surface of the board to make it follow the line printed on the board.

37 38

18

39

13. 10.5cm Twisted pair hookup wire (Part # CB10.2): This wire is used to transmit the 6.3V heating
filament voltage to the tube. Untwist about 1/4” (6-7mm) of each end of the twisted pair and
straighten the ends out with your pliers.40 Strip off about 1/8” (3-4mm) insulation from each end
of the two wires.41 On the solder side of the board, install the four stripped ends in the holes
marked “HEATERS”.42 It doesn’t matter which wire goes into which of the two holes. Solder each
of the four ends on the component side of the board.

43, 44

40 41

42 43

44

19

14. Tube socket (Part # SK10):
a. Before installing the tube socket, we need to help prepare it to easily seat the tube. These

sockets come a little tight from the factory, so it is helpful to loosen up the place where the tube
pins fit in.45 Very gently use your awl to slightly widen each of the 12 pin sockets.

46

45 46

b. The tube socket is installed on the solder side of the board. The leads may need to be pressed

in slightly for it to fit in the holes.47 Make sure all the leads are seated firmly and that the socket
is pushed in as close to the board as possible.48 Double check to make sure that the top of the
socket is parallel to the surface of the board.

47 48

c. Solder the leads of tube socket on the component side of the board.

49 50

49, 50

20

The circuit board is now complete!

Double check all your solder joints and make sure everything is well soldered and making good
connections. If anything looks at all sketchy, touch-up each solder joint. It’s much easier to fix a problem
with the board now than once it is installed in the chassis. Once you are satisfied with the PCB, put it
aside in a safe spot until the next section when it is installed it in the chassis.

21

LOADING THE CHASSIS

Note the chassis face with the big square hole is the BACK of the amp! Generally, hold the chassis
with the back AWAY from you unless told otherwise! This will help avoid building the thing backwards.

1. Grommets: Pop the 4 rubber grommets (Part # GR02) into the holes on top of the chassis as

shown.

51

51

BACK

RIGHTLEFT

FRONT

2. Power Transformer (Part # T1):
a. Cut the black wires coming from the power transformer to 4-5/16” (11cm).52 Put the black

wires that you just cut aside because you will use them later. Cut the brown and red wires to
2-3/4” (7cm).53 Strip off about 3/16” (4-5mm) of insulation from each of the 6 wires.54 Twist
together the tiny strands of wire on each of the stripped ends. Then “tin” the stripped part of
each wire.

55, 56

“Tinning” is the process of coating or filling a wire or connector contact with
solder to make it easier to attach. It also helps to keep the tiny strands of wire from fraying out
while you try to solder them. When you tin the transformer wires, make sure you do not use
too much solder; otherwise the wire will be too thick to fit into the PCB holes later.

52 53

22

54 55

56

b. The power transformer goes on the RIGHT side of the chassis (with the back of the chassis

AWAY from you). Pass the red and brown wires through the rear-right grommet, and the black
wires through the front-right grommet.

57

Align the transformer mounting holes with the holes in
the chassis. Use two M3x6 machine screws (Part # SC38) and two M3 Keps lock nuts (Part #
NU10) to mount the transformer.58 Screw down tight.59

57 58

59

23

c. Now you need to twist the wires. Twist the black wires together somewhat tightly, but do not

over twist the wires near where they emerge from the transformer. You do not want to stress
the wires near the transformer coil, because they can easily break on the inside of the
transformer, and that would be very bad. Also twist the red wires together and the brown
wires together in the same way (not too tight near the coil).

60

60

3. Output Transformer (Part # T2):
a. Cut all of the wires coming from the output transformer to 4” (10cm).

61, 62

Strip off about
3/16” (4-5mm) of insulation from each of the four wires. Twist together the tiny strands of wire
on each of the stripped ends and tin the stripped part of each wire.63 Don’t make the tinned
wire too fat.

61 62

63

b. The output transformer goes on the LEFT side of the chassis. Pass the green and black wires

through the left-rear grommet, and the blue and red wires through the front-left grommet.64
Screw the transformer down to the chassis, just like the power transformer, with two M3x6

24

machine screws (Part # SC38) and two M3 Keps lock nuts (Part # NU10).

65

64 65

c. Twist the green and black wires together, and twist the red and blue wires together, in the

same way as the power transformer wires.66 Once again, be mindful not to over twist the
wires close to the coil.

66

4. Fins (Part # CH05) (2 pcs): These flank the tube socket and shield the tube from the magnetic
fields from the transformers. Place them as shown, careful that they face the right way. If you put
them in backwards, the tube won’t fit later. If the fins look like the letter L, then the base of the L
points towards the tube opening. Use four #10x3/8” sheet metal screws (Part # SC68) to attach
the fins.67 DO NOT OVER-TIGHTEN THESE SCREWS! Just drive them in snug. If you over-tighten,
they will strip out the chassis.

67

25

5. Label (Part # PL11): Clean the front of the chassis with a clean rag moistened with isopropyl
alcohol, denatured alcohol, or rubbing alcohol.68 Clean it thoroughly, and allow any liquid to dry
completely. Be careful NOT TO TOUCH the face AT ALL after
cleaning. The oil on your fingertips will leave prints that will
interfere with the bond of the label. Test fit the label, then
peel off the back and carefully set it in place.69 GET IT
RIGHT THE FIRST TIME! YOU WILL NOT BE ABLE TO
RE-POSITION THIS LABEL! Line up the bottom edge of
the label with the bottom edge of the chassis; then align

TIP: If the label is

slightly misaligned over one

of the edges or holes use a

razor blade or xacto knife to

trim off the excess.

some of the chassis holes, drop it in place, and rub it
down firmly over the entire surface.

68 69

6. LED bezel (Part # SK05): Install the plastic LED bezel into its hole on the front of the chassis
(through the label).70 It goes in the hole to the right of the ZDL logo. It should easily snap into
place.

70

7. Install the PCB (Part # PC23):

a. Flip the chassis over so the fins and transformers are resting on the table top, and the front of

the chassis is facing you. Bend all the transformer wires to the outside of the chassis so that
they don’t get in the way of the placement of the PCB.71

26

71

b. Carefully place the circuit board in the chassis with the standoffs down (the standoffs resting

on the top of the chassis) and the component side of the board up. The input jack side of the
board should be closest to you. Slide the PCB forward as the input jack, pot, and switch fit
through the holes on the front of the chassis and the tube socket is seated in its chassis hole.72
You may have to hold the board at an angle while sliding it forward to get everything to fit
properly. Make sure all the transformer wires are between the front and back standoffs. The
standoffs should line up with the screw holes on top of the chassis.

72

c. Affix the PCB to the chassis with six machine screws (Part # SC38) placed through the chassis

holes into the standoffs.73 Don’t over tighten or cross-thread these screws.

73

27

d. Place the washer and nut back on the pot, and snug down with your pliers.74 Place the plastic

nut back on the input jack,75 and snug it down with your pliers. Do not over-tighten this nut or
the label could start warping.

74 75

e. Use your needle nose pliers to bend the LED over to fit inside of the LED bezel on the front of

the chassis.76 Be sure not to twist the LED or the leads might touch and short out against each
other. Push the LED through the bezel until it snaps into place.

76

8. Knob (Part # KN05): Turn the pot all the way counter clockwise. Place the knob on the pot and
align the white line on the knob to the position where you want the volume to be off (usually
between 1:00 & 2:00, when the amp is upside down). Use a small flat screwdriver to tighten the
set screw until the knob is tight.77 Now turn the knob all the way right and left through its travel.
The line should be between 10:00 & 11:00 at the maximum clockwise position. The goal in
setting the knob is to make the 6:00 position of the knob (when the amp is upside down) be the
half way point of the pot turn, in other words, the turning distance either side of middle should be
equal. If it’s not right, loosen the screw, adjust the knob, and re-tighten. It may take a few times of
re-adjustment to get the knob/pot position where you want it.

77

28

9. Wiring the PCB: Once the PCB is affixed to the chassis you can attach the transformer wires. All
of the wires will pass around the side of the PCB, and you will solder them on the component side
of the board.

a. Output transformer: Place the red wire into the square hole of P1, and then the blue wire to

the round hole of P1. Solder both connections.

78

78

b. Power transformer: Place the black wires into the holes of P4; it doesn’t matter which wire

goes in which hole.79 Place the red wires into the holes of P280, and then place the brown
wires into the holes of P3.81 In each pair, it does not matter which wire goes in which hole,
but MAKE SURE YOU MATCH THE COLOR TO THE CORRECT NUMBER! Solder all the wires
in their respective holes.

79 80

81

10. Grounding Wire (Part # CB10.3): Strip about 1/4” (6mm) of insulation off both ends of one of
the 4cm hookup wires. Using your needle nose pliers, bend a small hook in one stripped end of

29

the wire.82 Thread the hook through the small hole on the grounding lug (Part # CB20) and crimp
it tight with your pliers.83 Solder that connection.84 Put this assembly aside until next step.

82 83

84

11. IEC Power Receptacle (Part # J3):
a. Strip about 1/4” (6mm) of insulation off the ends of the other 4cm hookup wire (Part #

CB10.3).85 Attach the wire to the power receptacle lug as shown, with the wire pointing to
the left away from the power receptacle (study the picture carefully). Use the same hook and
crimp technique that you used in the previous step, but don’t solder it yet. MAKE SURE YOU
ATTACH THE WIRE TO THE CORRECT POWER RECEPTACLE LUG.

85

b. Now attach the other 4cm wire (the end opposite the ground lug) to the same power receptacle

lug . Attach it so the ground lug is pointing to the right, away from the power receptacle (study
the picture carefully).86

30

86

c. Now solder the wires to the lug. Be careful not to use too much heat or the lug could start

melting out of the plastic.87

87

d. Bend both wires slightly forward and push the power receptacle through the chassis. BE SURE

TO INSTALL IT WITH THE CORRECT SIDE UP (look at the picture).88 It may be a tight fit; it
could take some wrenching to get it to seat. Once it is seated properly, you can very gently
bend the four retaining tabs of the power receptacle up if you want to ensure a tighter fit.

89

88 89

31

e. Place the wire coming from the right side of the power receptacle (the wire without the ground

lug on it) in one of the 3 square ground pads on the PCB next to the power receptacle. Solder
this wire in place on the component side of the board.

90

90

f. Use your flat screwdriver to pry the fuse holder from the power receptacle.91 Pace the fuse

(Part # F1) in the holder92 and slide it back into the power receptacle.

93

91 92

93

12. Grounding Wire Revisited: Use a M3x6 machine screw (Part # SC38) and one M3 Lock Nut, (Part

# NU10) to attach the grounding lug to the back of the chassis as shown.94 Screw it down tight!

94

32

13. Wiring the IEC power receptacle:

WARNING: If you make a mistake here, you could expose yourself or others to electric

shock. Double check all your connections.

a. Retrieve the lengths of wire that you cut off the power transformer earlier. Cut each of the two

black wires to 4-1/4” (10.5cm) long.95 Strip about 3/16” (4-5mm) of insulation from each
end of both wires.96 Tin each end (don’t use too much solder).

95 96

b. Now twist the two wires together, to within about 3/8” of each end.97 Solder one end of the

pair to the holes labeled P5, IEC jack.

98

97 98

c. Solder the end of the wires to the IEC power receptacle, to the two lugs shown in the picture.99

It doesn’t matter which wire goes to which lug, JUST MAKE SURE YOU SOLDER THEM TO
THE CORRECT TWO LUGS! Mind the picture.

100

99 100

33

14. Output jack (Part # J2):
a. Remove the nut and washer from the output jack and install it on the back of the chassis.

Orient the jack so the lugs are facing up, as in the picture. The washer goes on the outside of
the jack, between the nut and the chassis.

101

b. With your needle nose pliers make a small hook in the stripped section of the feedback loop

wire (the long wire attached to the middle of the circuit board, in the FBL hole). Hook the FBL
wire on the “tip” lug of the output jack (note the picture below

102

, if you are not sure which is

the correct lug).

c. Next attach the green wire from the output transformer to the same lug (the “tip” lug) as the

FBL wire.

102

Solder both wires to the lug.

101

102

d. Next, attach the black wire from the output transformer to the ground lug (note the picture if

you are not sure which lug is the ground).

103

Solder the black wire to the lug.

103

34

15. Tube (Part # V1):
a. Take the tube out of its box and closely look at the pins.

Sometimes a few of the pins get bent in the handling
or shipping process from the factory. If any of the
pins are bent, very gently use your needle nose
pliers to straighten them out.

104

Do this step very
carefully and do not put too much torque on the pin
at the point where it comes out of the glass. If you do,
the glass could easily crack and allow the vacuum in the
tube to be compromised, which would mean we’d have to sell you a new tube.

104 105

TIP: You can tell if the

vacuum is bad in your tube

because the “getter flash” (the shiny

metallic section on the inside of the

glass) will turn white or clear.

105

b. Now flip the amp right-side-up again and install the tube in its socket. It can only go in one

way. Line up the pins and then gently rock the tube,
top, until it is completely seated in the socket.

106

pressing gently but firmly down on the

107

If it has a hard time fitting into the socket
make sure all the tube pins line up with the socket pins properly. If you still have trouble, you
might need to use your awl again to loosen the tube socket pins.

106 107

35

TESTING THE AMP

The testing process is done with the Percolator upside down. The transformers and fins should be
resting on the bench top. Make sure none of the weight of the amp is resting on the glass bottle of the
tube. If it is, put some blocks of wood under the transformers to jack the amp up a little bit.

A schematic of the amplifier is printed on the template sheet that came with the kit. This schematic is for
reference in troubleshooting, should you have problems with the amp. DC test voltages are labeled in
red on “Figure 3: Voltage Reference” on page 39. The test procedure will consist of systematically
measuring these voltages to ensure that your amp is within spec. Print this diagram and write your
measurements directly on it. You don’t have to know how to read a schematic to test these voltages, but
you do need to know how to use your digital multimeter.

1. WITH THE AMP UNPLUGGED, double check all your wiring. Look closely at the pictures and
make sure the wires on your amp are correctly positioned.

108 109

108,109

2. WITH THE AMP UNPLUGGED from the wall, double check your solder joints. Closely examine
every joint on the PCB and make sure they are good, solid connections.

3. Using a 1/4” speaker cable, plug the Percolator’s output jack into an 8 ohm speaker cabinet.
ONLY USE AN 8 OHM CABINET WITH THIS AMPLIFIER. WHENEVER YOU APPLY POWER TO
THIS AMP, MAKE SURE IT IS FIRST PLUGGED IN TO AN 8 OHM LOAD.

4. Make sure the Percolator’s power switch is in the off position (when the amp is upside down, the
switch should be up).

110

Plug the IEC power cable into the IEC power receptacle on the amp.
Make sure NOTHING is touching any part of the amplifier that shouldn’t be, and then plug the
power cable into the wall outlet.

WARNING! As soon as you plug in the Percolator, there is LINE VOLTAGE across some parts

of the exposed circuit board. Touching the board could shock, injure, or kill you! NEVER
TOUCH ANY PART OF THE CIRCUIT BOARD WHEN THE AMP IS PLUGGED INTO THE
WALL!

36

110

5. Before you turn the power switch on, set your multimeter to test AC voltage. Measure the AC
voltage across the IEC power receptacle as shown.

111

Depending on several (mostly uncontrollable)
factors, you should measure between 115VAC and 120VAC (or between 220VAC and 240VAC
if you got the international power transformer). The amplifier was designed to use 118VAC from
the wall outlet (230VAC for the international transformer), so the voltages listed in the test
procedure are based on that. If your AC voltage reading is different than 118VAC (or 230VAC),
then the voltage readings in the next few steps will be off proportionally. Theoretically, if the input
voltage from the wall outlet is off by a certain percentage then all of the rest of the voltages in the
amp will be off by the same percentage. The tolerances of the tube and the rest of the components
can easily vary by 5%, so that could cause a bit of voltage fluctuation as well.

111

6. Set your digital multimeter to read DC voltage. In this amp,
all DC voltages are measured with respect to ground, so
the black probe of your multimeter should be held at
ground potential. This amp has several places at ground
potential that are good to put your black probe. Any
of the vias (the tiny holes throughout the PCB) should

112

work.

Any one of the 3 square pads on the PCB
under the IEC power receptacle will work.
also use any place on the chassis, assuming the ground lug
is making good contact with the chassis.
on any of those places while making DC voltage measurements.

113

You could

114

Keep the black probe

37

TIP: Use a test lead

(a wire with small alligator
clips on both ends) to clip the
negative (black) lead of your

multimeter to the grounded chassis.

That will free up one hand.

112 113

114

7. Turn on the power switch.

WARNING! As soon as you turn on the Percolator, there is HIGH VOLTAGE across several

parts of the exposed circuit board. Touching the board could shock, injure or kill you!
NEVER TOUCH ANY PART OF THE CIRCUIT BOARD WHEN THE AMP IS PLUGGED INTO
THE WALL!

The red LED should immediately turn on

115

(if it does, skip to the next step). If it doesn’t, then
measure the junction of C12 and R17 (TP2 in “Figure 3: Voltage Reference” on page 39). It
should read around 6.5VDC. If it does, it means you either installed the LED backwards, or you
installed the wrong resistor in R17. Switch off the amp, unplug the power cable and fix the
problem. If TP2 does not read around 6.5VDC (by a large percentage) double check C12 and/
or BR2 to make sure they are in the proper orientation.

115

38

WARNING: Capacitors contain high-voltage electricity hours after the amp is unplugged!

Handling the capacitor could shock or burn you! If you must remove or re-solder a capacitor,
either let it sit unplugged overnight, or safely discharge it as described in the tip below.

8. Figure 3 has 11 DC test voltages (in red) with arrows
pointing to the place on the circuit board where these
voltages should be found. The points are numbered
TP1 through TP11 (“TP” stands for “test point”). In
the figure next to each voltage is a box for you to
write down the voltage that you actually measure.
Remember, you are measuring from ground (with
the black probe) to the red point (with the red
probe).

116

Start on the left side of the board and

the other lead to the positive side of

TIP: To safely discharge

a capacitor: Get a 1k-10k ohm,

2w resistor and solder or clip test

leads to the resistor legs. Clip one

of the leads to the chassis, and clip

the high-voltage cap. The cap will

discharge in a few seconds.

work your way from point to point, writing down each
voltage as you measure it. All the voltages should be fairly close
to the printed value, but if the line voltage (from the wall outlet) is above or below 118 VAC (or
230VAC for the international version), then these voltages will be off by the same percentage. If
any of these voltages are significantly off beyond this line voltage percentage, then it is very likely
that one or more of the components are installed in the wrong place. Triple check the resistors,
capacitors, and bridge rectifiers by visually inspecting each one. If they are all correct, then triple
check each solder joint. If you make any changes, use your multimeter to re-test the voltages that
were incorrect. If you have to get to the solder side of the board, you’ll have to unsolder all the
transformer wires from the board, and remove the IEC receptacle, as well as unscrew the front
panel components and stand off screws from the chassis.

Figure 3: Voltage Reference

39

116

TIP: If it turns out that

you need to re-solder any of the

resistors, don’t bother removing the
board from the chassis to get to the
solder side, just solder them on the

component side of the board.

9. Once the voltages are all within spec, carefully plug your guitar (or harp mic) into the input jack,
taking care not to touch the exposed circuit board. Make some noise.

117

Turn up the volume. It

should sound great!

117

40

ASSEMBLING THE CHASSIS

1. Turn the power switch off. Unplug any cables that are plugged in to the amp (power, speaker,
instrument). Carefully seat the chassis base plate (Part # CH03.2) onto the inverted chassis.
is a snug fit.

118

118

It

2. Use four sheet metal screws, pan head Philips #8x1/2 (Part # SC63), two in front

120

back

, to secure the chassis to the base plate. Use a #2 Philips screw driver (not a screw gun)

119

, two in

and turn just until seated. DO NOT OVER-TIGHTEN or you could warp the label, or even worse,
strip out the screw hole.

119 120

That’s it! The electronics part of your amp is done. Good job. If you plan on installing the amp into the
cabinet (a simple task), those notes are in the section “COMPLETING THE HEAD” on page 67. If
you are not planning on using the cabinet provided, you are free to go rock out. See “USING YOUR
NEW HEAD” on page 69.

41

BUILDING THE CABINET

While the amp is an intermediate to advanced electronics project, the cabinet is a beginner’s
woodworking project. On the other hand, while the amp can be built in an hour, it takes several hours
over several days to complete the cabinet! Take your time, be careful, and you should produce a lovely
solid wood cabinet to be proud of.

We are going to show you how we make the pre-finished Percolator here in our lab. There are as many
carpentry and finishing techniques as there are carpenters and finishers. If you prefer to do something
differently, go for it. If you have an experienced friend to work on this with you, take his or her advice
over ours.

WHAT YOU WILL NEED

To build the cabinet, you will need the following:

1. Tools

• Drill: cordless, corded, or drill press

• Drill bits: 1/16, 9/64, 3/16

• Orbital Sander (optional) or sanding block

• Small router and 3/16” radius roundover bit, or other small detail bit (optional)

• Countersink (see also text below)

• #2 Phillips Screw Driver, short shaft

• #2 Phillips Screw Driver

• Awl, or nail and small hammer

• Staple gun. We prefer electric or pneumatic, but manual will work fine.

• Sharp pencil

• 12” Ruler

• Bar clamp, minimum 10” opening

• Razor, X-Acto knife, or scissors

• Speed square or carpenter square

• Channel locks or large pliers

• Heat gun, or very hot hair dryer

2. Supplies

• Good quality wood glue such as TiteBond II or III

• Masking tape

• Good quality wood filler such as DAP Plastic Wood (optional)

• Sandpaper, either discs for your orbital, or sheets for your block: 60, 120, 220, 320

• Very small can of MinWax Dark Walnut Wood Finish #2716 (oil base stain)

• Small can of MinWax Wipe-On Poly clear satin

• A tiny bit of flat black paint, spray or can, or if you’re in a pinch, permanent black marker

42

(like a Sharpie)

• Mineral spirits, for cleanup

• Clean rags

• A Percolator cabinet kit (no kiddin’)

A WORD ON COUNTERSINKS

The overall success of this project depends somewhat on your ability to accurately countersink the
wood screws, so that the heads lie just below the surface of the wood, but no deeper. There are several
ways to do this:

• buy a #6 pilot bit (9/64) with matching fluted countersink and stop collar, or an all-in-one #6
pilot / counterbore / countersink tool

• buy a countersink bit

• Use a ¼” drill bit in a drill press

The first (shown to the left) is our favorite: very accurate and easy to use. The
second, a countersink bit (shown to the right), is next best. If you don’t do a
lot of wood working, you may not want to invest in these tools. This leaves
using a ¼ drill bit in a press. To do this, first drill through with the 9/64

43

bit, then countersink with the ¼ bit, carefully and gradually adjusting the depth of plunge until the full
diameter of the bit just barely cuts into the wood. The screw should then pull the head down into the
wood and just below the surrounding surface. Practice setting the depth on a scrap of pine until you
like the results.

ALWAYS provide a 1/16” pilot in the holding piece of wood, and keep the clutch on your screw gun
set low when driving, or the screws provided are likely to spin out or break.

ASSEMBLING THE BOX

1. Fitting the Wood Parts (Part # CA05). Note that the longer wood parts are the top and bottom
(Part # CA05.1) and the shorter pieces (Part # CA05.2) are the sides. Arrange the four pieces of
wood as shown in the diagram. If you have a preference for the appearance of grain, color,
knots, etc, flip the parts around this way and that until you like the way they look.
the wood exhibits blemishes on one side from the milling process. Face these toward the inside.
They will be completely invisible and will have no effect on the quality of the cabinet.

121

121

Sometime,

2. With the pencil, label the parts where it won’t show, so you can easily fit them together again
later. Put the labels towards the front of each piece.

122

122

3. With scissors or blade, cut out the templates provided with your kit.

123

If you ruin them, they also
appear at the end of this document. Tape the templates to the top, the bottom and the right-hand
side (as you face the front).

124, 125

If the templates do not match the wood size PERFECTLY (it

happens), line up the FRONT EDGE of the template to the FRONT EDGE of the wood, and center

44

123 124

125

it along the length of the wood. Don’t worry about the REAR edge.

4. With the awl, or nail and a small hammer, carefully poke a hole into the wood at the center of
each cross hairs.

126

Remove the template from the right side,
down to the LEFT side and mark that piece as well.
a PAIR of parts, not two IDENTICAL parts.

130

129

Take care when you do this that you create

127, 128

flip it over and tape it face-

NOTE: You don’t have to use the handle provided with your kit. You can use any handle you

like, but in that case, check the hole spacing before you poke your marks in the cabinet top!

126 127

128 129

45

130

5. Stand up all four pieces of wood on their FRONT edges on your clean, smooth, flat work surface.
Dry-fit them together. Use the bar clamp to snug the pieces together as shown.

132

If your clamp
has no plastic pads, DO NOT OVER-TIGHTEN or you’ll mar the wood. It just needs to be snug.
Pick one corner and line up the pieces of wood as carefully and accurately as you can.
sure the faces (the sides touching the table) are flush to each other at the joint.

134

If the parts are

133

not precisely the same width (it happens), they will be a tiny bit uneven on the back face (that
is, the sides facing up). That’s okay; don’t worry about it – it’s the back. You can fix it later when
finishing the cabinet.

When you are satisfied with the alignment of one corner, tighten the clamp to secure the parts
for drilling.

Take your time with this step. The overall neatness of your cabinet depends on getting this step right.

131 132

131

Be

133 134

6. Fit your drill with the 1/16” bit, sticking out about 1-1/8”. These break easily; you may want to
pick up a spare. At the corner you lined up, drill two holes at your marks, through the side and
into the mated wood piece.

135

46

135

7. Continue to the other three corners, loosening the clamp and lining up the corners one by one.
Drill a total of 8 holes.

136

136

8. Disassemble the four pieces and lay them flat on your worktable with the outsides facing up. Still
with the 1/6” bit, drill four pilot holes about ½” deep in the bottom as indicated on the template,
for the screws that will hold on the feet.

137

Note these are the four OUTER holes, nearest the

corners.

137

9. With the 9/64 bit, or the combo drill / countersink bit,
re-drill the eight small holes you made in the sides, plus
7 other holes as indicated on the templates: one more
on each side, one on the top, and four on the bottom.
NOTE: These four holes on the bottom are the four

TIP: You will get

cleaner holes on the inside of
the parts if you can drill straight
through the cabinet parts into a

piece of plywood.

47

INNER holes, further away from the corners. They are for mounting the chassis and need to be as
accurate as possible. A drill press is great for this if you have one. Otherwise, be careful to hold
the drill perpendicular to the wood surface. Drill and countersink a total of 15 holes.

138, 139

138 139

When you countersink, practice on the four bottom holes, where the depth is less critical. Go
easy, test-fit a screw, and deepen the countersink a little as necessary. The head should sit below
the surface of the surrounding wood, but only just.

140

140

10. With the 3/16 bit, drill the two holes in the cabinet top for the handle screws.

NOTE: If you use a handle other than the one provided, check the screw size before drilling

these two holes in the cabinet top!

141

48

141

11. Inspect the inside faces of the wood pieces for splinters or “blowout”: bits of wood standing above
the surrounding surface. Clean these off with a bit of 120-grit sandpaper.

142

142

12. Re-assemble and dry fit the parts,

143

with the front edges facing DOWN.
one end of the TOP. Smooth the glue with a stick until it uniformly coats the end.
much!

143 144

145

144

Apply some wood glue to

145

You don’t need

13. Fit two wood screws into the appropriate two holes of the mating SIDE piece.
into the little pilot holes in the top piece.
and place the bar clamp tightly across the parts to hold them secure. Use a #2 Philips screwdriver
or cordless screw gun to drive the screws barely snug.
adjustable clutch, set it very low, like 2 or 3. Leave the joint a little loose for now.

146

Guide the tips

147

Line up the joint accurately as you did earlier,

149

Do not over-tighten! If your drill has an

49

148,132

146 147

148 149

14. Now attach the BOTTOM to the same SIDE, driving the screws barely snug.

150

150

15. Now apply glue to the remaining exposed ends of both the TOP and BOTTOM.
into the remaining SIDE and maneuver them into all four little pilot holes.

152

151

Fit four screws

Align one joint
tighten the bar clamp (not shown; very foolish of us to attempt this without the clamp). Carefully
drive the two screws barely snug, then align the last joint, and set the last two screws, barely

154

snug.

See also our online video for proper placement of the bar clamp.

153

and

50

151 152

153 154

16. Check the box for overall squareness: press the face flat to the table; measure diagonally across
the cabinet to see if it measures the same in both directions.
clamp across the longer diagonal and gently tighten it to bring the box closer to square.
tighten all eight screws.

158

If any glue appears on the outside of the box, wipe it off with a rag

155, 156

If necessary, install the bar

157

Now

dipped in warm water.

155 156

157 158

51

Let the cabinet sit for at least 4 hours for the glue to cure.

159

159

17. If any joints are poorly mated, grind them flush with 60 or 80 grit sandpaper.

160, 161

160 161

18. Edge Detail: If you want to apply a router detail, now’s the time. There’s only room for a small
chamfer or roundover. (If you don’t want to use a router, you can achieve a similar look just with
vigorous hand-sanding.) We use a 3/16” roundover bit with a bearing at the bottom.

162

As
you route each edge, be careful to orient the router so that you do not run the bearing across
the screw heads.

163

This will result in blemishes that could ruin your cabinet! Round over all the

outside edges except the four back edges.

DANGER! Routers are dangerous, tricky machines that can do you a serious harm if misused.

If you are unfamiliar with routers, get a friend to help you!

162 163

52

19. If there are chips, or gaps in your joints that you cannot live with, fill them with wood dough. LET
THE WOOD DOUGH HARDEN THOROUGHLY BEFORE SANDING!!

164

That’s it! Congratulations.

Take a break, and when you are ready (maybe tomorrow), we’ll sand and finish the box.

53

FINISHING THE BOX

There are lots of ways to apply a beautiful, durable finish to a solid wood box. Following is how we
finish our cabinets here at the Lab. You may finish your Percolator any way you like. Please send us
photos of your completed project for our gallery!

Your cabinet is made of top-grade solid poplar. This is a dense, very finely grained softwood. It is
harder, more stable and more durable than pine. It is the wood of choice for all fine millwork that is
destined to be painted, but properly prepared it stains nicely too.

1. Do not sand the interior of the cabinet at all. Sand the whole exterior twice, using 120 and 220
grit sandpapers.

a. If you routed a detail, carefully sand out any burn marks, and be careful you do not obliterate

your detail with the orbital sander.

165

b. “Ease” the square edges; that is, strike off the sharp square edge the mill applied to the wood.

Your finish ingredients cannot accumulate on a sharp edge. Don’t use the orbital for this, at
least not for the inside edges; sand the square edges by hand only.

166

Be thorough! The better job you do here will strongly influence how nicely your stain turns

167

out.

166 167

2. Remove the dust: blast it with compressed air, draw it off with a vacuum, or wipe with a clean rag.

54

3. Apply a liberal coat of MinWax Dark Walnut Wood Finish #2716 with a rag.
based stain, one of the easiest to use. Coat the entire cabinet inside and out,
off again with a clean rag.
streaks.

173

Set the cabinet down on its back, propped up on a few pencils, or chopsticks, or

triangular strips of wood. Let it dry for at least 4 hours!

171, 172

Rub it out thoroughly and carefully, leaving no fingerprints or

174

168 169

170 171

168

This is an oil-

169, 170

then wipe it

172 173

174

55

4. Use a clean rag to apply a coat of MinWax Wipe-On Poly Clear Satin.

175

This is a remarkable
product that is thick enough to provide a decent finish, but thin enough to soak straight into the
wood without running or dripping. Pour a little product into a disposable metal or plastic cup, like
the bottom inch cut from a soda can. Dip your rag and apply a generous coat to the whole
cabinet, inside and out.

176-178

Set it back down on its back to dry thoroughly, like, overnight.

175 176

177 178

179

179

5. Very lightly hand sand the exterior of the cabinet with 320 grit sandpaper.

180

Ignore the interior;
it’s done. The finish is thin, so be careful you do not remove the poly and damage the stained
wood underneath. You are trying to strike off the fuzzy grain raised in the finishing process so far.
This sanding should produce a fine white powder that feels soft as velvet to the touch.
off with a clean cloth.

182

181

Wipe it

56

180 181

182

6. Clean up your work space as best you can. Remove all the dust from the cabinet and the work
table. Sweep or vacuum the floor. It is dust in the air that affects the final finish.

7. Apply a second coat of Wipe-On Poly to the exterior. Allow to dry thoroughly.

183, 184

183 184

8. At this point, if the box is beautiful and satiny-smooth, you are done. If it is still a little fuzzy or
uneven, sand lightly with 320 grit sandpaper and apply a third light coat. Allow to dry thoroughly.

57

ASSEMBLING THE CABINET

1. On the cabinet bottom, install the four little feet (Part # FT03) with four little sheet metal screws
#6x5/8” (Part # SC66) into the four little 1/16” holes near the corners.

185

185

Do not over-tighten.

2. Use a short screw driver to install the handle,

186 187

188

186

using the screws that came with it.

187, 188

The cabinet is done!

58

ASSEMBLING THE GRILL

1. Lay out the four wood pieces as shown.

189

2. Apply a drop of glue to both ends of both long pieces. Spread it out to coat the entire end of the

190

stick.

190

189

3. Fit the pieces together and place a bar clamp across the width of the frame.
clamp down on the frame just until you see glue squeezing out of all four corners.

191

Gently snug the

192

Wipe off the

excess glue with a damp rag. Allow at least 4 hours for the glue to cure.

191 192

4. Remove the clamp.

5. Paint the inside surfaces, and one face, with flat black paint (or a permanent black marker).
Allow to dry completely.

193, 194

59

193 194

6. Now it is time to put on the grill cloth. Attaching grill cloth in a way that looks nice is not an easy
task. There are 2 goals to keep in mind when working with grill cloth: 1) Keep the lines straight;
nobody thinks crooked or wavy grill cloth looks good. 2) Make the grill cloth tight. Saggy grill cloth
is almost as unattractive as wavy lines. There are several different techniques for accomplishing
these two goals, but the process described here has worked well for us. If you aren’t confident
about doing this step, call your local upholstery shop and they might be able to help you out.

The first part of putting on grill cloth consists of folding the 4 sides while carefully following
straight lines.

a. Set the grill cloth face-down on the table. The face is the side with a distinct grid pattern and

broken black lines.

195

Place the frame black-side-down neatly centered on the grill cloth.

196

Align one of the long sides with one of the silver lines about an inch from the edge of the grill
cloth. Remove the frame and fold the cloth over on the silver line and crease it the entire length
of the grill cloth.

197

The bent edge should be at a 90 degree angle.

198

195 196

197 198

60

b. Place the frame back on the grill cloth (with the long edge against the fold) and line up one of

the short sides with one of the black lines on the grill cloth about one inch away from the edge
of the cloth.
folded crease to the chosen black line. DO NOT OVER CUT THIS LINE.
cloth at the black line and crease it the entire width of the cloth.

199

Remove the frame, and use scissors or a razor to cut the grill cloth along the

200

Fold over the grill

201

199 200

201

c. Place the frame back on the cloth with the edges against the two folds. Now find the line on

the grill cloth (one of the threads) that is parallel and closest to the other long side of the frame.
Remove the frame and cut the grill cloth along the short folded crease to this new parallel line.
Once again, DO NOT OVER CUT THIS LINE.
parallel line the entire length of the grill cloth.

202

Fold and crease the grill cloth on the new

203, 204

202 203

61

204

d. With the frame resting between the 3 folds, find the line that is parallel and closest to

remaining short side of the frame. Remove the frame and cut the grill cloth on each of the
long-side folds up to this new line. ONCE AGAIN, DON’T OVER CUT.
along this line.

207, 208

205, 206

Fold and crease

205 206

207 208

7. While holding the frame (black side down) onto the grill cloth, turn the assembly around and look
at the front. The edges of the grill cloth should wrap tightly around the frame, and all the lines on
the cloth should be parallel or perpendicular to the frame sides. Check the straightness of the lines
(in both directions) with your speed square and make sure the back of the grill cloth is flat against
the front of the frame.

209

62

209

8. Place the assembly face down on the table. While holding the grill cloth in its proper place, use
your staple gun to put one staple in the middle of each side of the frame. Make sure the staple is
right in the middle of the side in both directions (up/down and left/right).

210

210

9. Re-examine the assembly to make sure the grill cloth lines are still straight (use your speed
square)

211

and check to make sure the back of the grill cloth is still tight against the face of the
frame. If so, proceed with placing staples around the outside. Start in the middle of each side and
move to the corners. Alternate sides with each staple. Make sure that all of the staples seat
completely, or the frame may not fit into the amp cabinet. If some of the staples need to be pushed
in further, you can use your channel locks to squeeze them in. Periodically check with your speed
square that the lines are remaining straight (in both directions). Don’t worry about getting the grill
cloth too tight on this step, just concern yourself with getting the lines straight. If you notice some
of the lines are going crooked pull out the necessary staples and start over. Take your time and
you will be pleased with the results.

212-214

211 212

63

213 214

10. When you are done stapling and the lines are all straight, cut the surplus lengths of the grill cloth
from the corners of the frame.

215

215

11. Fold the remaining grill cloth over to the back of the frame and staple it down. Leave about 1/2”
from the corners without any staples.

216

216

12. At one corner of the frame, hold both corners of the grill cloth down, one on top of the other. Use
your razor to cut a 45 degree line through both layers of cloth, from the corner of the frame.
Remove both cut corners of grill cloth.
Do this for the other 3 corners.

219

218

Use one staple to hold down the grill cloth in the corner.

217

64

217 218

219

13. Use a match or lighter to carefully singe the loose threads at the corners as shown.

220

Move the

flame quickly - grill cloth melts very fast.

WARNING: Open flames are dangerous, especially around flammable material such as

grill cloth and wood. Use common sense.

220

14. If the grill cloth seems looser than you are comfortable with then you can use your heat gun to
tighten it up. This is a tricky process to apply just enough heat to tighten it up, but not enough to
cause the lines to warp and go crooked, or even worse, burn through the grill cloth. We suggest
you practice on some of the scraps you just cut from the frame assembly. This will give you an
idea of how easily the grill cloth is affected by your heat gun. Start with the heat gun on the lowest
setting and if that isn’t hot enough, you can move up from there. Also, start with the heat gun at
least 12” away from the grill cloth; move closer if necessary. Move in broad, uniform movements

65

over the entire area, warming the whole frame evenly. Be patient and take your time, and you
should be pleased with the results.

221, 222

221 222

66

COMPLETING THE HEAD

INSTALLING THE AMP

1. Place the cabinet upright on the table and carefully slip the amp in.

223

It should be a pretty nice

slide-fit side-to-side. Looks nice, eh?

223

2. Carefully turn the amp over and stand it on-end, with the bottom facing you. Use one hand to hold
the amp firmly in place against the cabinet bottom.

224

224

3. Run a sheet metal screw flat head Philips #6x1 (Part # SC67) through one of the countersunk holes
in the cabinet bottom. Use a #2 Philips driver, NOT a screw gun! If we all did our jobs well, the
screws will line up perfectly with the holes in the chassis and will dig right in. Hold the amp tight
to the cabinet and drive the screw in until you feel it pull the amp down tight. DO NOT OVER­TIGHTEN THESE SCREWS or they will strip out the chassis. Repeat for all four screws.

225 226

225, 226

67

INSTALLING THE GRILL

1. Fit the grill frame into the front of the cabinet, above the amp. Push it in flush to the cabinet front.
It should be an easy fit side-to-side; it may be a tight fit up-and-down.

2. Fit a 1/16” drill bit to stick about 1-1/8” out of your screw gun, or use your combo piloting bit.
Center the grill frame left and right. Carefully pass the bit through the countersunk hole in the
cabinet top and drill a pilot hole in the frame. Next, drill the other two holes through the sides of
the cabinet into the sides of the frame.

227

3. Run a #6x1-1/4” wood screw (Part # SC61) through the hole in the top of the cabinet and into
the top of the grill frame. Repeat for the two side screws. Do not over-tighten the side screws; you
just want to hold the frame in place, not pull it apart!

227

228, 229

228 229

That’s it! You are done!! Congratulations.

68

USING YOUR NEW HEAD

For information about using your new head please read “The Percolator Owner’s Manual,” available
for download on the product page at the Zeppelin Design Labs website.

69

0

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4321

TOP

9/64"

9/64"

PAGE 1 of 3

REV. DATE 1/27/2015

9/64"

REAR

0

FRONT

PERCOLATOR 2W AMP

FULL SIZE DRILLING TEMPLATES

CABINET SIDE

9/64"

VERIFY THE TEMPLATE PRINTS ACCURATELY

TO FULL-SIZE: CHECK BOTH SCALES WITH

RULER. MAKE SURE PRINTER IS SET FOR 100%.

1/16" PILOT INTO CABINET TOP & BOTTOM;

THROUGH HOLE 9/64";

COUNTERSINK FOR WOOD SCREW.

5 THROUGH HOLES, 3-STEP PROCESS:

1.

2.

3.

FLIP TEMPLATE OVER AND APPLY FACE-DOWN

TO CABINET LEFT SIDE.

9/64"

BOTTOM

© 2015 ZEPPELIN DESIGN LABS. NO PART OF THIS DOCUMENT MAY BE REPRODUCED WITHOUT WRITTEN PERMISSION FROM THE AUTHOR.

WWW.ZEPPELINDESIGNLABS.COM

ZEPPELIN DESIGN LABS, LLC

2950 N WESTERN AVE CHICAGO IL 60618

0

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PAGE 2 of 3

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REV. DATE 1/27/2015

RIGHT

"61/3

FRONT

REAR

PERCOLATOR 2W AMP

FULL SIZE DRILLING TEMPLATES

0

9/64"

CABINET TOP

HANDLE: 2 THROUGH HOLES 3/16"

GRILLE FRAME, 1 THROUGH HOLE 9/64";

COUNTERSINK.

"61/3

VERIFY THE TEMPLATE PRINTS ACCURATELY

TO FULL-SIZE: CHECK BOTH SCALES WITH

RULER. MAKE SURE PRINTER IS SET FOR 100%.

LEFT

© 2015 ZEPPELIN DESIGN LABS. NO PART OF THIS DOCUMENT MAY BE REPRODUCED WITHOUT WRITTEN PERMISSION FROM THE AUTHOR.

WWW.ZEPPELINDESIGNLABS.COM

ZEPPELIN DESIGN LABS, LLC

2950 N WESTERN AVE CHICAGO IL 60618

0

4321

PAGE 3 of 3

REV. DATE 1/27/2015

3

1/16" 1/16"

9/64"

9/64"

1/16"

21

PERCOLATOR 2W AMP

FULL SIZE DRILLING TEMPLATES

0 4

CABINET BOTTOM

FEET: 4 BLIND HOLES 1/16", ABOUT 1/2" DEEP.

CHASSIS MOUNT: 4 THROUGH HOLES 9/64",

COUNTERSUNK.

9/64"

VERIFY THE TEMPLATE PRINTS ACCURATELY

TO FULL-SIZE: CHECK BOTH SCALES WITH

RULER. MAKE SURE PRINTER IS SET FOR 100%.

© 2015 ZEPPELIN DESIGN LABS. NO PART OF THIS DOCUMENT MAY BE REPRODUCED WITHOUT WRITTEN PERMISSION FROM THE AUTHOR.

9/64"

1/16"

WWW.ZEPPELINDESIGNLABS.COM

ZEPPELIN DESIGN LABS, LLC

2950 N WESTERN AVE CHICAGO IL 60618