Delta 31-481 User Manual

26 IN. Dual Drum Sander

Ponceuse à double tambour de 66 cm

Lijadora de Tambor Doble de 26 in.

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Español (34)

www.DeltaMachinery.com

Operating Instructions and Parts Manual

Manuel d’utilisation

Manual de instrucciones

INSTRUCTIVO DE OPERACIÓN, CENTROS	481
DE SERVICIO Y PÓLIZA DE GARANTÍA.

LÉASE ESTE INSTRUCTIVO

ANTES DE USAR EL PRODUCTO.

TABLE OF CONTENTS

IMPORTANT SAFETY INSTRUCTIONS	...................................2
SAFETY GUIDELINES - DEFINITIONS....................................	3
GENERAL SAFETY RULES ......................................................	3
POWER CONNECTIONS ..........................................................	5
MOTOR SPECIFICATIONS .......................................................	5
GROUNDING INSTRUCTIONS ................................................	5
EXTENSION CORDS ................................................................	6
FEATURES AND COMPONENTS.............................................	6
FUNCTIONAL DESCRIPTION ..................................................	7
PRODUCT SPECIFICATIONS...................................................	7
UNPACKING ..............................................................................	7
ASSEMBLY ................................................................................	8
Securing Switch to Frame ...................................................	8
Table Elevation Crank Handle .............................................	8
Dust Collect .........................................................................	8
ADJUSTMENTS.........................................................................	9
Replacing the Sanding Belt .................................................	9
Feed Belt Tracking ...............................................................	9
Drive Belt Tension ..............................................................	10
Replacing Feed belt ..........................................................	11

Parallelism of Sanding Drums ...........................................	12
Roller Pressure ..................................................................	12
Drum Height ......................................................................	13
OPERATION .............................................................................	13
OPERATING TIPS....................................................................	13
Depth of Wood Removal ...................................................	13
Sanding Imperfect Stock ...................................................	13
Stock Feeding Angle .........................................................	14
Multi-Piece Sanding ..........................................................	14
Face Frames and Raised Panel Doors .............................	14
Edge Sanding ....................................................................	14
SELECTING ABRASIVES........................................................	14
MAINTENANCE PROCEDURES ............................................	15
Routine Inspection .............................................................	15
Lubrication .........................................................................	15
Cleaning the Sanding Belts ...............................................	15
TROUBLESHOOTING .............................................................	15
ACCESSORIES........................................................................	16
WARRANTY .............................................................................	16
FRANÇAIS................................................................................	18
ESPAÑOL .................................................................................	34

IMPORTANT SAFETY INSTRUCTIONS

READ AND UNDERSTAND ALL WARNINGS AND OPERATING INSTRUCTIONS BEFORE USING THIS EQUIPMENT. Failure to follow all instructions listed below, may result in electric shock, fire, and/or

serious personal injury or property damage.

Woodworking can be dangerous if safe and proper operating procedures are not followed. As with all machinery, there are certain hazards involved with the operation of the product. Using the machine with respect and caution will considerably lessen the possibility of personal injury. However, if normal safety precautions are overlooked or ignored, personal injury to the operator may result. Safety equipment such

as guards, push sticks, hold-downs, featherboards, goggles, dust masks and hearing protection can reduce your potential for injury. But even the best guard won’t make up for poor judgment, carelessness or inattention. Always use common sense and exercise caution in the workshop. If a procedure feels dangerous, don’t try it. Figure out an alternative procedure that feels safer. REMEMBER: Your personal safety is your responsibility. For additional information please visit our website www.DeltaMachinery.com.

This machine was designed for certain applications only. DELTA® Power Equipment Corporation strongly recommends that this machine not be modified and/or used for any application other than that for which it was designed. If you have any questions relative to a particular application, DO NOT use the

machine until you have first contacted DELTA® to determine if it can or should be performed on the product.

If you have any questions relative to its application DO NOT use the product until you have written DELTA® Power Equipment Corporation and we have advised you. Contact us online at www.DeltaMachinery.com or by mail at Technical Service Manager, DELTA® Power Equipment Corporation, 99 Roush Street, Anderson, South Carolina 29625.

Information regarding the safe and proper operation of this tool is available from the following sources:

•Power Tool Institute, 1300 Sumner Avenue, Cleveland, OH 44115-2851or online at www.powertoolinstitute.com

•National Safety Council, 1121 Spring Lake Drive, Itasca, IL 60143-3201

•American National Standards Institute, 25 West 43rd Street, 4 floor, New York, NY 10036 www.ansi.org - ANSI 01.1 Safety Requirements for Woodworking Machines

•U.S. Department of Labor regulations www.osha.gov

2

SAFETY GUIDELINES - DEFINITIONS

This manual contains information that is important for you to know and understand. This information relates to protecting YOUR SAFETY and PREVENTING EQUIPMENT PROBLEMS. To help you recognize this information, we use the symbols below. Please read the manual and pay attention to these sections.

Indicates an imminently hazardous situation which, if not avoided, will result in death or serious injury.

Indicates a potentially hazardous situation which, if not avoided, could result in death or serious injury.

Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate injury.

Used without the safety alert symbol indicates potentially hazardous situation which, if not avoided, may result in property damage.

GENERAL SAFETY RULES

WARNING FAILURE TO FOLLOW THESE RULES MAY RESULT IN SERIOUS PERSONAL INJURY.

•FOR YOUR OWN SAFETY, READ AND UNDERSTAND THE INSTRUCTION MANUAL BEFORE OPERATING THE UNIT. Learn the unit’s application and limitations as well as the specific hazards peculiar to it.

•KEEP WORK AREA CLEAN. Cluttered areas and benches invite accidents.

•DON’T USE IN DANGEROUS ENVIRONMENT. Don’t use this unit in damp or wet locations, or expose it to rain. Keep work area well-lighted.

•KEEP CHILDREN AND VISITORS AWAY. All children and visitors should be kept a safe distance from work area.

•DISCONNECT UNIT before servicing.

•CHECK DAMAGED PARTS. Before further use of the unit, properly repair or replace any part that is damaged.

FAILURE TO FOLLOW THESE RULES MAY RESULT IN SERIOUS INJURY.

1.Read and understand the warnings posted on the machine and in this manual. Failure to comply with all of these warnings may cause serious injury.

2.Replace the warning labels if they become obscured or removed.

3.This Dual Drum Sander is designed and intended for use by properly trained and experienced personnel only. If you are not familiar with the proper and safe operation of a drum sander, do not use until proper training and knowledge have been obtained.

4.Do not use this machine for other than its intended use. If used for other purposes, Delta Power Equipment Company, Inc. disclaims any real or implied warranty and holds itself harmless from any injury that may result from that use.

5.Always wear approved safety glasses/face shields while using this Dual Drum Sander.

6.Before operating this drum sander, remove tie, rings, watches and other jewelry, and roll sleeves up past the elbows. Remove all loose clothing and confine long hair. Non-slip footwear or anti-skid floor strips are recommended. Do not wear gloves.

7.Wear ear protectors (plugs or muffs) during extended periods of operation.

8.Some dust created by power sanding, sawing, grinding, drilling and other construction activities contain chemicals known to cause cancer, birth defects or other reproductive harm. Some examples of these chemicals are:

•Lead from lead based paint.

•Crystalline silica from bricks, cement and other masonry products.

•Arsenic and chromium from chemically treated lumber.

Your risk of exposure varies, depending on how often you do this type of work. To reduce your exposure to these chemicals, work in a well-ventilated area and work with approved safety equipment, such as face or dust masks that are specifically designed to filter out microscopic particles.

1.Do not operate this machine while tired or under the influence of drugs, alcohol or any medication.

2.Make certain the switch is in the OFF position before connecting the machine to the power source.

3.Make certain the machine is properly grounded.

4.Make all machine adjustments or maintenance with the machine unplugged from the power source.

continued on page 4

3

5.Form a habit of checking to see that all extra equipment such as adjusting keys, wrenches, scrap, stock, and cleaning rags are removed away from the machine before turning on.

6.Keep safety guards in place at all times when the machine is in use. If removed for maintenance purposes, use extreme caution and replace the guards immediately when maintenance is complete.

7.Make sure the drum sander is firmly secured to the floor before use.

8.Check damaged parts. Before further use of the machine, a guard or other part that is damaged should be carefully checked to determine that it will operate properly and perform its intended function. Check for alignment of moving parts, binding of moving parts, breakage of parts, mounting and any other conditions that may affect its operation. A guard or other part that is damaged should be properly repaired or replaced.

9.Provide for adequate space surrounding work area and non-glare, overhead lighting.

10.Keep the floor around the machine clean and free of scrap material, oil and grease.

11.Keep visitors a safe distance from the work area. Keep children away.

12.Make your workshop child proof with padlocks, master switches or by removing starter keys.

13.Give your work undivided attention. Looking around, carrying on a conversation and “horseplay” are careless acts that can result in serious injury.

14.Maintain a balanced stance at all times so that you do not fall or lean against the sanding belt or other moving parts. Do not overreach or use excessive force to perform any machine operation.

15.Use the right tool at the correct speed and feed rate. Do not force a tool or attachment to do a job for which it was not designed. The right tool will do the job better and safer.

16.Use recommended accessories; improper accessories may be hazardous.

17.Maintain machinery with care. Follow instructions for lubricating and changing accessories.

18.Turn off the machine before cleaning. Use a brush or compressed air to remove dust or debris — do not use your hands.

19.Do not stand on the machine. Serious injury could occur if the machine tips over.

20.Never leave the machine running unattended. Turn the power off and do not leave the machine until it comes to a complete stop.

21.At all times hold the stock firmly.

22.Do not use this sander for other than it intended use. If used for other purposes, Delta Power Equipment Company Inc., disclaims any real or implied warranty and holds itself harmless for any injury or damage which may result from that use.

SAVE THESE INSTRUCTIONS.

Refer to them often and use them to instruct others.

4

POWER CONNECTIONS

A separate electrical circuit should be used for your machines. This circuit should not be less than #12 wire and should be protected with a 20 Amp time lag fuse. If an extension cord is used, use only 3-wire extension cords which have 3-prong grounding type plugs and matching receptacle which will accept the machine’s plug. Before connecting the machine to the power line, make sure the switch (s) is in the “OFF” position and be sure that the electric current is of the same characteristics as indicated on the machine. All line connections should make good contact. Running on low voltage will damage the machine.

DO NOT EXPOSE THE MACHINE TO RAIN OR OPERATE THE MACHINE IN DAMP LOCATIONS.

MOTOR SPECIFICATIONS

Your machine is wired for 230 volts, 60 HZ alternating current. Before connecting the machine to the power source, make sure the switch is in the “OFF” position.

THIS MACHINE MUST BE GROUNDED WHILE IN USE TO PROTECT THE OPERATOR FROM ELECTRIC SHOCK.

GROUNDING INSTRUCTIONS

1. All grounded, cord-connected machines:

In the event of a malfunction or breakdown, grounding provides a path of least resistance for electric current to reduce the risk of electric shock. This machine is equipped with an electric cord having an equipment-grounding conductor and a grounding plug. The plug must be plugged into a matching outlet that is properly installed and grounded in accordance with all local codes and ordinances.

Do not modify the plug provided - if it will not fit the outlet, have the proper outlet installed by a qualified electrician.

Improper connection of the equipment-grounding conductor can result in risk of electric shock. The conductor with insulation having an outer surface that is green with or without yellow stripes is the equipment-grounding conductor. If repair or replacement of the electric cord or plug is necessary, do not connect the equipment-grounding conductor to a live terminal.

Check with a qualified electrician or service personnel if the grounding instructions are not completely understood, or if in doubt as to whether the machine is properly grounded.

Use only 3-wire extension cords that have 3-prong grounding type plugs and matching 3-conductor receptacles that accept the machine’s plug, as shown in Fig. A.

Repair or replace damaged or worn cord immediately.

IN ALL CASES, MAKE CERTAIN THE RECEPTACLE IN QUESTION IS PROPERLY GROUNDED. IF YOU ARE NOT SURE, HAVE A qualified ELECTRICIAN CHECK THE RECEPTACLE.

Fig. A

Fig. B

5

EXTENSION CORDS

				Use proper extension cords. Make	MINIMUM GAUGE EXTENSION CORD
				sure your extension cord is in good
					RECOMMENDED SIZES FOR USE WITH STATIONARY ELECTRIC MACHINES
	condition and is a 3-wire extension cord which has a
	3-prong grounding type plug and matching				Ampere	Volts	Total Length	Gauge of Extension
	receptacle which will accept the machine’s plug.				Rating		of Cord in	Cord
	When using an extension cord, be sure to use one						Feet
	heavy enough to carry the current of the machine.				0-6	120	up to 25	18 AWG
	An undersized cord will cause a drop in line voltage,
					0-6	120	25-50	16 AWG
	resulting in loss of power and overheating. The table				0-6	120	50-100	16 AWG
	on the right shows the correct gauge to use				0-6	120	100-150	14 AWG
	depending on the cord length. If in doubt, use the
	next heavier gauge. The smaller the gauge number,				6-10	120	up to 25	18 AWG
	the heavier the cord.				6-10	120	25-50	16 AWG
					6-10	120	50-100	14 AWG
					6-10	120	100-150	12 AWG
					10-12	120	up to 25	16 AWG
					10-12	120	25-50	16 AWG
					10-12	120	50-100	14 AWG
					10-12	120	100-150	12 AWG
					12-16	120	up to 25	14 AWG
					12-16	120	25-50	12 AWG
					12-16	120
							greater than 50 feet not recommended
							Fig. C

KEY FEATURES AND COMPONENTS

1. Variable speed feed belt

2. 3HP continuous duty motor

3. Dual 26” drums

4. Sanding elevation cursor

5. Elevation crank handle

6. Switch assembly

Fig. 1

6

FUNCTIONAL DESCRIPTION

Model 31-481 DELTA® 26” Dual Drum Sander is specifically designed to handle both rough and final sanding processes in a single pass. This machine features an adjustable height automatic feed table and comes with 80-grit and 120-grit pre-cut sanding belts already installed. This dual drum sander is powered by a 3HP continuous duty sealed motor with a variable speed feed that enables you work at 3-20 S.F.P.M. The wide feed belt accepts stock as big as 25 ½” and allows you to sand pieces up to 12 ¼” thick.

PRODUCT SPECIFICATIONS

Drum Motor Specifications

Type		Induction Ball bearing/
		Continuous Duty
Horsepower		3HP
Amps		16A
Voltage		230V
Phase		Single
Hertz		60Hz
RPM		3,450
Belt Feed Motor Specifications
Type		Universal
Horsepower		1/6
Product Specifications
Maximum sanding width		25-1/2”
Maximum board thickness		12-1/4”
Minimum board thickness		¼”
Minimum board length		6”
Feed Speed		3-20 FPM (variable)

Number of Sanding Drums	2
Drum Size	5” x 26”
Drum Speed	1,550 RPM
Dust Ports	2-4”
Product Dimensions
Footprint	17-3/4” x 43”
Length	31”
Width	46”
Height	53”
Weight	485 lbs.
Shipping Dimensions
Carton Type	Wooden Crate
Length	33”
Width	48”
Height	55”
Gross Weight	535 lbs.

Unpacking

The machine is heavy, be careful when removing it from the shipping container! Failure to comply may cause serious injury and/or damage to the sander and/or property!

Your Delta® Dual Drum Sander comes packed in a single container. Use a safety strap to avoid tip over when lifting machine. Check shipping carton and machine for damage before unpacking.

Open the shipping container. Carefully remove packaging materials, parts and machine from shipping carton. Always check for and remove protective shipping materials around motors and moving parts. Lay out all parts on a clean work surface and check that all parts are present and in good condition:

Description (Quantity)

Delta 26” Dual Drum Sander (1) 12mm Open End Wrench (1) Elevation Handle (1)

5mm Hex Wrench (1) 6mm T-Handle Wrench (1) 2mm T-Handle Wrench (1) Elevation Bracket (1)

Compare the items to inventory figures; verify that all items are accounted for before discarding the shipping box. Report any missing or damaged parts to your distributor or dealer. Prior to tool assembly and use, read this manual thoroughly to familiarize yourself with proper assembly, maintenance and safety procedures.

Remove any protective materials and coatings from all of the parts and the drum sander. The protective coatings can be removed by spraying WD-40 on them and wiping it off with a soft cloth. This may need to be redone several times before all of the protective coatings are removed completely.

If any parts are missing, do not attempt to plug in the power cord and turn “ON” the machine. The machine should only be turned “ON” after all the parts have been obtained and installed

correctly.

7

ASSEMBLY

Tools Required

•Flat head screw driver

•10mm open-end wrench

SECURE SWITCH BOX TO FRAME

Tools Required: 10mm open-end wrench

Parts: None

Hardware Needed: Two 10mm hex head screws

1. Locate the two threaded holes on the upper right side of the machine as shown in Fig. 2.

2. Attach the two 10mm hex head screws to the mounting

plate, leaving about 1/8” between the screw head and mounting plate.

3. Mount switch assembly (A) to the machine frame by aligning the keyholes (B) in the switch assembly over the screw heads and pushing the assembly back and into

position.

Fig. 2

4. Tighten screws using 10mm open-end wrench.

ASSEMBLE TABLE ELEVATION

CRANK AND HANDLE

Tools Required:

None

Parts: Table Elevation Crank Table Elevation Handle

Hardware Needed: None

1. Install the table elevation crank (C) by aligning the groove in the bottom of the crank with the pin located on

the shaft (D). See Fig. 3.

2. Screw the table elevation handle into the threaded hole in the table elevation crank.

Fig. 3

CONNECT DUST COLLECTOR TO DUST COLLECTION PORT

Tools Required: Flat head screwdriver

Parts: None

Hardware Needed: Two 4” Ring Clamps (not provided)

Your Delta® Dual Drum Sander is equipped with two 4-inch dust collection ports. These must be connected to dust collector hoses to ensure safe operation.

Do not attempt to operate this tool without first connecting it to an adequate dust collection system.

1.Fit a 4” ring clamp over the end of each dust collection hose.

2.Place a dust collection hose over each dust collection port and tighten ring clamp with the flat head screwdriver.

8

ADJUSTMENTS

TO REPLACE THE SANDING BELT

1.Lift the upper guard up and tilt it toward the rear of the machine to expose the drums.

2.Locate the spring-loaded locking clamp (A) on the right end of the drum. Squeeze the clamp open and remove the end of the sanding belt (B) from the drum slot. See Fig. 4.

3.Slowly pull the old sanding belt off the drum.

4.Squeeze the spring-loaded locking clamp on the left end of the drum and remove the old sanding belt.

5.Squeeze the spring-loaded locking clamp on the left end of the drum and insert the end of the new sanding belt approximately 2 inches into the drum slot.

6.Release the clamp to lock the belt end in place.

7.Rolling the roller by hand, carefully wind the sanding belt around the drum, making sure to keep it snug. The edges of the belt should meet without overlapping.

8.Squeeze the locking clamp on the right end of the drum and insert as much of the end of the sanding belt into the slot as possible.

9.Release the clamp to lock the belt in place.

10.Roll the roller by hand to ensure the belt is snug and the edges meet without overlapping.

Fig. 4

NOTE: The Dual Drum Sander is designed to achieve coarse and fine sanding in a single pass. Therefore, the coarser sanding belt should always be installed on the front roller with the finer belt on the rear roller.

TO ADJUST THE FEED BELT TRACKING

For proper stock feed, both sides of the feed belt must travel at exactly the same rate. If the feed belt tracks to the right or left during operation, you will need to adjust the tension.

NOTE: If the belt tracks to the left, tighten the left tensioning bolt. If it tracks to the right, tighten the right tensioning bolt.

1. Locate the feed belt tensioning bolts as shown in Fig. 5.

2.Turn the sander on and, depending on which direction the feed belt is tracking, use a 6mm Allen wrench to tighten either the left or right adjustment

bolt in 1/4-turn increments until the feed belt tracks	Fig. 5
evenly.

9

ADJUSTMENTS

TO ADJUST DRIVE BELT

TENSION

1.Remove the elevation cursor by unscrewing the retaining screw.

2.Remove the eight Phillips head bolts and washers

securing the left and right side guards (A) to the machine and remove the guards. See Fig. 6.

3. Use a 6mm Allen wrench to remove the four hex cap bolts and washers securing the bottom guard

(B) to the machine. See Fig. 7.

4.Raise the telescoping panels (C) high enough to

expose the motor mount (D). See Fig. 7. Prop up using a scrap block of wood.

5. Locate the two M12 nuts (E) that raise and lower the motor. See Fig. 7.

6. To increase tension on the drive belts, loosen the bottom nuts then tighten the top nuts.

7.Drop the telescoping panels back into place and re-secure to the bottom guard.

8.Re-attach the side guards and elevation cursor.

Fig. 7

Fig. 6

10

ADJUSTMENTS

TO REPLACE THE FEED BELT

This step requires two adults. The feed table is heavy, be careful when disconnecting and removing it from the machine. Failure to comply may cause serious injury and/or damage to the

sander and/or property!

1.Using the table elevation crank and handle, lower the table as far as it will go.

2.Release tension on the feed belt by backing off the locking nuts (A) on the feed belt adjustment bolts (Fig. 8) and then tightening the feed belt adjustment bolts (B) until they are loose enough to

remove the feed belt assembly.

3.Loosen but do not remove the eight Philips head screws (C) holding the bearings to either side of the front of the feed table. See Fig. 9.

4. Remove the front guard (D) by sliding it forward.

5. Locate and remove the four 6mm hex head screws

(E) securing the feed table to the base. See Fig. 10.

6. With the aid of a second adult, carefully remove the feed table through the rear of the machine being

careful to angle it away from the motor housing.

7. Position the feed table on its side and remove the worn feed belt.

8. Carefully slide the new feed belt into place.

Fig. 9

9. Slide feed belt assembly back onto machine base through the rear, being careful not to damage motor housing.

10. Replace and tighten the four 6mm hex cap head screws to secure the feed table to the machine base.

11. Replace the front guard and retighten the Phillips head screws on each bearing.

12. Re-tension the feed belt.

13. Adjust the tracking as described on page 9.

Fig. 10

Fig. 8

11

ADJUSTMENTS

TO ADJUST PARALLELISM OF SANDING DRUMS

The front sanding drum has been factory adjusted and needs no further adjustment. The rear sanding drum must be adjusted for parallelism.

1. Lift the upper guard up and tilt it toward the rear of the machine to expose the sanding drums.

2. Using the 6mm wrench provided, rotate the cap screws, indicated in Fig. 11, on either end of the rear drum.

3. Turning the cap screws clockwise will raise the drum while turning it counterclockwise will lower the drum.

4.Repeat this dial setting on the opposite end of the drum.

5.Replace the upper guard to its original position over the drums.

Fig. 11

NOTE: For proper operation of the machine, the dial settings at both ends of the drum must be identical.

TO ADJUST ROLLER PRESSURE

The pressure rollers maintain tension upon the workpiece as it passes through the machine. If the stock refuses to pass through the machine, or the finished surface is uneven, the tension on the pressure rollers may need adjusting.

1.Lift the upper guard up and tilt it toward the rear of the machine to expose the sanding drums.

2. Locate the roller pressure adjustment screws as indicated in Fig. 12.

3. Using a Phillips head screw driver, turn the screws clockwise to increase the roller pressure on the workpiece; or counterclockwise to decrease the pressure.

4. Adjust both sides of the pressure rollers to ensure parallelism with the drums.

5.Replace the upper guard to its original position over the drums.

Fig.12

Do not overtighten the adjustment screw. Too much roller pressure will prevent the workpiece from passing through the machine, and may cause the feed belt to stop.

12

ADJUSTMENTS

TO ADJUST DRUM HEIGHT

In order to accommodate different abrasive grits on the drums, the height of the drums from the workpiece must vary. The height of the front drum has been factory set and should not be adjusted. The back drum is designed for easy adjustment.

1.Lift the upper guard up and tilt it toward the rear of the machine to expose the sanding drums.

2.Locate the drum height adjustment screw as shown in Fig. 13.

3.Rotate the adjustment screw to the desired measurement.

4.Repeat this same adjustment at the opposite end of the roller to maintain parallel orientation to the front drum.

5.Replace the upper guard to its original position over the drums.

NOTE: For proper operation of the machine, the dial settings at both ends of the drum must be identical.

IMPORTANT: The chart at the right shows the proper settings based upon sanding grits.

Fig. 13

Front Grit / Rear Grit	Setting (mm)
80/100, 120/150, 120/180, 150/220	.15
80/120, 100/150, 100/180	.30
60/100, 36/38	.40
36/120	.56
36/60	.76
36/80	.9

OPERATION

The basic operating procedure for the Dual Drum Sander is as follows:

1.Establish the depth of wood removal and set table height.

2.Start drums.

3.Start feed belt and select proper feed rate.

4.Ensure dust collection system is running.

5.Feed stock through machine.

OPERATING TIPS

DETERMINING DEPTH OF WOOD REMOVAL

Given the variables of grit abrasion, wood type, and feed rate, determining proper depth of removal may take some experimentation. For best results, use scrap wood to practice sanding and to develop skill and familiarity with the machine before doing finish work. Also consider any cups and/or crowns in the workpiece.

A good rule of thumb when sanding with grits finer than 80 is to lower the drum so it contacts the workpiece but drum can still be rotated by hand. For grits coarser than 80, lower the drum slightly more.

SANDING IMPERFECT STOCK

When sanding stock with a cup or crown, place the crown up. This will stabilize the stock to help prevent tipping or rocking during sanding. After the crown has been removed and the top is flat, turn the stock over and sand the opposite side. To avoid personal injury, take special care when sanding stock that is twisted, bowed, or otherwise varies in thickness from end to end.

If possible, support such stock as it is being sanded to keep it from slipping or tipping. Use an extra roller stand, help from another person, or hand pressure on the stock to minimize potentially hazardous situations.

13

OPERATING TIPS

STOCK FEEDING ANGLE

Some pieces, because of their dimensions, will need to be fed into the machine at a 90-degree angle (perpendicular to the drums). However, even a slight offset angle of the stock will provide for more effective stock removal. The optimum feeding angle is about 60-degrees. Angling the workpiece for stock removal provides other advantages, such as less loading of certain areas of the drums due to glue lines or mineral streaks in the stock, more even wear of abrasive strips, potentially faster feed rates, and lighter loads on the motor. For the best final finish, however, the stock should be fed with the grain on the final one or two passes.

MULTIPLE-PIECE SANDING

When sanding multiple pieces simultaneously, make sure to stagger (step) the pieces across the width of the feed belt. Multiple pieces should also be of similar thickness and this helps to ensure consistent contact with the pressure rollers.

SANDING FACE FRAMES AND RAISED PANEL DOORS

It is important to have the proper abrasive contact when doing this type of sanding. If the machine is set to take an excessive depth of cut, the result can be a gouge or dip as the drum goes from sanding the rails at full width to sanding just a few inches of width of the stiles.

EDGE SANDING

When edge sanding, the sander will mimic the opposite edge of the stock which is lying on the feed belt. Because of this, it is important for the stock edge to have been ripped at the proper angle to the face before the sanding process. When edge sanding small stock, clamp several pieces together to prevent them from slipping on the feed belt.

SELECTING THE PROPER ABRASIVES

The abrasive material you choose will have a substantial effect on the performance of your sander. Variations in paper type, weight, coating and durability all contribute to achieving your desired finish.

As with any sanding operation, first begin sanding with a coarser grit, depending on the roughness of the stock or the amount of stock to be removed. Then progressively work toward finer grits. This means if you are using two different grits on your 31-481 Dual Drum Sander, the coarser grit should always be placed on the front drum.

The amount of stock to be removed is a major consideration when initially choosing the grit grade. Grits 36 and 60 are primarily designed for stock removal; grits over 100 are primarily finishing grits designed to remove the scratch pattern from the previous grit used.

For best results, never skip more than one grit grade when progressing through a sanding sequence. For fine work, such as furniture, try not to skip any grit grades during the sanding process. In general, premium quality abrasives will produce a better finish with a less noticeable scratch pattern.

CAUTION: Grits that are too fine can sometimes burnish the wood and leave a glossy surface which will not accept stains evenly. This will vary by type of wood. Oak, for example, is susceptible to burnishing because of its open pores.

READY-TO-CUT ABRASIVE STRIPS

Description	Normal Use
60 Grit Sandpaper	surfacing and dimensioning
	boards, trueing warped
	boards
80 Grit Sandpaper	surfacing, light dimensioning,
	removing planer ripples
120 Grit Sandpaper	light surfacing, minimal stock
	removal
150 Grit Sandpaper	finish sanding, minimal stock
	removal
180 Grit Sandpaper	finish sanding only, not for
	stock removal
220 Grit Sandpaper	finish sanding only, not for
	stock removal.

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RECOMMENDED MAINTENANCE PROCEDURES

ROUTINE INSPECTION

It is recommended that you periodically inspect your Delta® Dual Drum Sander as a precautionary action. During this time, check all hardware such as bolts, nuts and screws to ensure they are properly tightened. Also verify that the sanding belts and drive belts are mounted properly and have not become loose or torn.

Also take this opportunity to inspect for dust and/or wood particles that may have accumulated on or in the machine.

LUBRICATION

The table height adjustment screw shafts, located at either end of the machine must be well lubricated with grease at all times. In order to access, inspect and lubricate the screw shafts, it is necessary to remove the two side guards located on either end of the machine.

To remove the side guards:

1.Remove the elevation cursor by unscrewing the retaining screw.

2.Remove the eight Phillips head bolts and washers securing the left and right side guards to the machine and remove the guards. See Fig. 14.

3. Re-attach side guards and elevation cursor.

CLEANING THE SANDING BELTS

Regularly clean the sanding belts on the drums with commercially available cleaning sticks, following the manufacturer’s directions. When cleaning, also brush the stick crumbs from the sanding drum while it is still rotating.

Fig. 14

Troubleshooting guide

	PROBLEM	POTENTIAL CAUSE	SOLUTION
		Sanding grit too fine.	Change to a coarser grit.
		Too much material being removed at once.	Adjust table height.
	Sanding surface clogs too	Dirty board surface.	Ensure board is free of debris prior to sanding.
	quickly.	Insufficient dust collection.	Inspect dust collection system.
		Board contains too much moisture.	Properly dry stock before sanding.
		Worn sanding belt.	Replace sanding belt (Page 9)
		Drums not parallel to feed table.	Re-align drums (Page 11)
	Sanding belt tears.	Sandpaper edges overlapped.	Re-install sanding belt.
		Tape is slipping.	Rewind the loose belt on the drum.
		Too much material is removed at once.	Lower the table height.
	Rounding on the edges.	Too much material is removed at once.	Lower the table height.
	Uneven thickness on right	Drums are not parallel to feed table.	Re-align drums (Page 11)
	and left side of the board.	Uneven wear of sanding paper.	Replace sanding belt.
	Stock slips on the feed	Too much material is removed at once.	Lower the table height.
		Too much dust on the feed belt surface.	Clean surface with air hose.
	belt.
		Worn feed belt.	Replace feed belt (Page 9)
	Shiny spots on sanded	Sanding paper too old.	Replace sanding belt (Page 9)
	surface.	Drums too high.	Lower table height.
	Marks on sanded surface	Partial damage to sanding paper.	Replace sanding belt (Page 9)
		Paper overlapped on edges.	Re-align sanding belt on drum
	Feed belt does not	Feed belt tension is incorrect.	Adjust feed belt tension (Page 9)
	run smoothly or stops
		Belt tracking is incorrect.	Adjust feed tracking (Page 9)
	completely.
		No out-feed support.	Use supplementary support in rear of
	Consistently noticeable		machine.
	“snipe”	Pressure roller spring tension incorrect.	Check and adjust.
		Drum height incorrect in relation to pressure rollers.	Adjust pressure rollers (Page 12)

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