Wood lathe user guide

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Shop Area: Woodshop

Tool: Lathe

Requires in-person training: Yes 

Procedure Number

UG 110-07, Rev. 1

Date

1/20/2021

 

GENERAL

Woodshop has 3 Lathes

Grizzly Model G0462 Wood Lathe is designed to turn wood stock so the operator can remove material with a hand-held cutting tool or chisel. 

Grizzly Lathe.png

Jet Lathe

Jet Lathe.png

Nova Lathe

Nova Lathe.png

SAFETY

  • Face shield to be worn when operating the lathe
  • Before operating, remove tie, rings, watches and other jewelry, and roll sleeves up past the elbows. Remove all loose clothing and confine long hair.
  • Do not wear gloves.
  • Remove tools left on lathe before starting lathe to eliminate dangerous projectiles.
  • This machine is intended for cutting natural and man-made wood products, and some plastics. Never attempt to cut any metal, stone, or rubber workpiece; cutting these materials can lead to machine damage or severe injury.
  • Do not use excessive force while cutting.
  • Verify each workpiece is free of knots, splits, nails, or foreign material to ensure it can safely rotate on spindle without breaking apart or causing tool kickback.
  • Before mounting piece, cut off waste portions to balance workpiece for safe rotation and remove large edges that can catch on tooling.
  • Verify tool rest, headstock, and tailstock are secure before turning lathe on.
  • Always verify workpiece is well-secured before starting lathe.
  • Use sharp tools to cut with less resistance than dull tools. Using dull tools increases the risk of tool kickback or grabbing.
  • Always allow rotating workpiece to stop on its own. Never put hands or another object on workpiece to stop it.

REFERENCE

PROCEDURE

  • Variable speed adjustment from 600–2400 RPM.
  • A digital readout provides a precise reading of the spindle speed.
  • Select correct spindle speed for workpiece size, type, shape, and condition. Use low speeds when roughing or when turning large, long, or non-concentric workpieces.
  • Allow spindle to reach full speed before turning.
  • Ability to rotate and move the head for turning workpieces with diameters larger than 12" on the outboard side of the lathe.
  • Adjust tool rest approximately 1⁄4" away from workpiece and 1⁄8" above workpiece center line to provide proper support for turning tool. Firmly hold turning tool with both hands against tool rest.
  • Test each new setup by starting spindle rotation at lowest speed and standing to side of lathe until workpiece reaches full speed and you can verify safe rotation.
  • Before starting spindle, verify workpiece has adequate clearance by hand-rotating it through its entire range of motion.
  • Only measure workpiece after it has stopped.
  • Roughing - Take light cuts, use low speeds, and firmly support tool with both hands.
  • Sanding or polishing - To reduce entanglement risk, remove tool rest before sanding. Never completely wrap sandpaper around workpiece.
  • Cutting wood with a moisture content over 20% causes unnecessary wear on tooling blades, increases the risk of tool grab, and yields poor results.
  • Workpieces with excessive bowing or twisting are unstable and unbalanced. Never turn these workpieces at high speed, or instability will be magnified and the workpiece can be ejected from the lathe causing impact injures.
  • Only turn concentric workpieces.

Grizzly Lathe Operation.png

Operation:

1. Examine the workpiece to make sure it is suitable for turning. No extreme bows, knots, or cracks should exist.

2. Prepare and trim the workpiece to make it roughly concentric.

3. Install the workpiece between centers, or attach it to a faceplate or chuck.

4. Adjust the tool rest to 1⁄8" above the workpiece centerline, and set the minimum clearance between the workpiece and the lip of the tool rest to 1⁄4".

5. Rotate the workpiece by hand to verify that the spindle and workpiece rotate freely throughout the full range of motion.

6. Start the lathe, adjusts the lathe speed, and carefully begin the turning operation, keeping the chisel against the tool rest the entire time it is cutting.

Adjusting Head:  headstock can be positioned anywhere along the bed and pivoted up to 180˚.

1. Disconnect Lathe from power.

2. Loosen the head lock lever.

3. Slide the headstock to the desired position, then retighten the lock lever.  Note: The large hex nut under the headstock may require occasional adjustment to ensure proper clamping pressure to the bed. Turn the hex nut in small increments to fine tune the clamping pressure, as needed.

To Pivot the Headstock:

1. Disconnect Lathe from power.

2. Make sure the head lock lever is tight.

3. Pull the pivot lock pin out and pivot the headstock clockwise 90˚ or 180˚.

4. Release the pivot lock pin. Make sure the pin has engaged in its detent by trying to rotate the headstock.

Adjust Tailstock Position:

1. The tailstock is equipped with a cam-action clamping system to secure it.

2. When the lock lever is tightened, a locking plate lifts up and secures the tool rest to the bed.

3. To reposition the tailstock along the bed, loosen the tailstock lock lever, move the tailstock to the desired position, then retighten the lock lever.

4. If the lock lever does not securely clamp the tailstock down onto the bed, loosen or tighten the hex nut located on the underside of the tailstock in small increments to achieve the proper clamping pressure.

Adjust Tool Rest:

1. The tool rest is equipped with a cam-action clamping system to secure it. When the base lock lever is tightened, a clamping plate lifts up and secures the tool rest to the bed.

2. For safe and good turning results, position the tool rest approximately 1⁄4" away from the workpiece, and approximately 1⁄8" above the workpiece center line.

3. Three-way adjustable tool rest.

• Use the base lock lever to secure the tool rest along the length of the bed.

• Use the pivot arm lock lever to secure the tool rest at a working distance from the workpiece.

• Use the tool rest lock lever to adjust the height and angle of the tool rest relative to the workpiece.

Installing Spur Center: The spur center installs in the spindle and forces the workpiece to spin with the spin.  The spur center is driven into the workpiece, then the center is inserted with the workpiece into the spindle.

1. Disconnect Lathe from power.

2. Move the tailstock and tool rest a safe working distance from the headstock.

3. If the faceplate is installed, remove it.

4. Make sure the spur center and the inside of the spindle are free of debris and oily substances that could interfere with proper mating of the parts.

5. Insert the tapered end of the center into the spindle, then push it in with a quick, firm motion.

6. Make sure the center is securely installed by attempting to pull it out by hand—a properly installed center will not pull out by hand.

Installing Spur Center:

1. Disconnect Lathe from power.

2. Hold a clean rag under the spindle or wear a glove to catch the center when you remove it.

3. Insert the knockout tool through the outboard end of the spindle and firmly tap the center until it breaks loose.

Installing Live Center:  The live center installs into the tailstock quill and rotates with the workpiece.

1. Move the tailstock a safe working distance from the head and tool rest.

2. Loosen the quill lock lever, then rotate the quill handwheel clockwise until the quill extends out from the tailstock about 1".

3. Make sure the live center and the inside of the quill are free of debris and oil substances that could interfere with the proper mating of these parts.

   4. Insert the tapered end of the live center into the quill with a quick, firm motion.

5. Make sure the center is secure by attempting to pull it out by hand—a properly installed center will not pull out by hand.

6. Rotate the quill handwheel to draw the quill back into the tailstock as far as possible without forcing the center to release. Note: The more the quill is drawn back into the tailstock, the greater the workpiece support.

7. Tighten the quill lock lever to hold the quill and center in place.

Removing Live Center: 

1. Loosen the quill lock lever.

2. Hold a clean rag under the center or wear a glove to catch the center when you remove it.

3. Rotate the quill handwheel counterclockwise to retract the quill back into the tailstock until the center is forced out

Installing Faceplate:  The faceplate is used when you need to remove material from the face of the workpiece, such as during hollowing operations. The faceplate can be installed only if the spur center is removed from the spindle.

1. Disconnect Lathe from power.

2. If the spur center is installed, remove it.

3. Make sure the internal threads of the faceplate and the threads of the spindle are free of any debris, then wipe the threads with a lightly oiled rag to aid in the installation and removal.

4. Thread the faceplate onto the spindle clockwise.

5. Use the two included 32mm flat wrenches to tighten the faceplate.

Removing Faceplate:  To remove the faceplate, perform Steps 3–4 in reverse.

Adjusting Spindle Speed: 

The lathe operates between 600 and 2400 RPM's. Due to the design of the pulley system, RPM's outside of this range cannot be attained.

Use the digital readout as a guide. Select a speed within the set range by pulling out the speed control lever and turning it to the right to increase RPM or to the left to decrease the RPM.

When turning a workpiece where a lot of material must be removed and a rough finish does not matter, low range, which has more torque, is best.

When turning a workpiece where a clean finish is required, and only light cuts are made, high range is best. Mid-range is a compromise between the two ranges. Use the speed lever to adjust the spindle speed within each range.

Both the diameter of the workpiece and the type of cutting should be considered when determining the proper spindle speed.

Diameter of Workpiece Roughing RPM General Cutting RPM Finishing RPM
Under 2” 1520 2400 Fastest Available
2 – 4“ 760 1600 Fastest Available
4 – 6” Slowest Available 1080 1650
6 – 8” Slowest Available 810 1240
8 – 10” Slowest Available Slowest Available 1000
10 – 12” Slowest Available Slowest Available 830
12 – 14” Slowest Available Slowest Available 710

Turning Tools:

Gouges — Used for rough cutting, detail cutting, and cove profiles. The rough gouge is a hollow, double-ground tool with a round nose, and the detail gouge is a hollow, double-ground tool with either a round or pointed nose.

Skew Chisel — A very versatile tool that can be used for planing, squaring, V-cutting, beading, and parting off. The skew chisel is flat, double-ground with one side higher than the other (usually at an angle of 20-40˚).

Scrapers — Used where access for other tools is limited, such as hollowing operations.This is a flat, double-ground tool that comes in a variety of profiles (Round Nose, Spear Point, Square Nose, etc.) to match many different contours.

Parting Tools — Used for sizing and cutting off work. This is a flat tool with a sharp pointed nose that may be single- or doubleground.

Specialty Tools — These are the unique, special function tools to aid in hollowing, bowl making, cutting profiles, etc.

Spindle Turning:  is the operation performed when a workpiece is mounted between the spindle and quill centers.

1. Mark both ends of your workpiece by drawing diagonal lines from corner to corner. The intersection point of these lines will show you the center of your workpiece.

2. Use a wood mallet to tap the point of the spur center into the workpiece where the lines intersect so that it leaves a center mark, then remove the center. Do this to both ends of the workpiece.

3. Use a 1⁄4" drill bit to make a 1⁄4" deep hole at the center mark on the workpiece end that will be mounted on the spindle spur center.

4.To help embed the spur center into the workpiece, cut 1⁄8" deep saw kerfs into the same workpiece end along the diagonal lines marked in Step 1.

5. If your workpiece is over 2" x 2", cut the corners off the workpiece length-wise to make turning the corners safer and easier.

6. Use a wood mallet to embed the spur center at least 1⁄4" into the workpiece end center mark.

7. With the workpiece still attached, insert the spur center into the spindle.

8. With the live center installed in the quill, draw the quill back into the spindle as far as possible without forcing the center to release. Note: This will give the quill and center the greatest amount of support to safely hold the workpiece during operation.

9. Loosen the tailstock lock lever, slide the tailstock toward the workpiece until the live center touches the workpiece centerpoint, then lock the tailstock in this position.

10. Use the quill handwheel to push the live center into the workpiece at least a 1⁄4", then tighten the quill lock lever to secure the center and quill.

11. Position the tool rest approximately 1⁄4" away from the workpiece and approximately 1⁄8" above the center line.

12. Test the setup by hand-turning the workpiece to make sure there is enough clearance all the way around before turning the lathe on.

Spindle Turning Tips:

• When turning the lathe ON, stand outside the path of the rotating workpiece until the lathe reaches full speed and you can verify that the lathe will not throw the workpiece.

• Use the slowest speed when starting or stopping the lathe, and when rough cutting.

• Select the correct speed for the size of the workpiece you are turning. Use slower speeds for large workpieces (4" diameter and over); use the middle range speeds for medium sized workpieces (2"–4" diameter); and use faster speeds for small sized workpieces (under 2" in diameter).

• Keep the turning tool on the tool rest the ENTIRE time that it is approaching the workpiece and is in contact with it.

• Learn the correct techniques for each tool you will use.

Faceplate Turning: when a workpiece is mounted to the faceplate that is then mounted to the spindle. This type of turning is usually done with open-faced workpieces like bowls or plates.

Attaching Faceplate to Spindle:

1. Mark the center of the workpiece. Note: Cut off the excess corners of the workpiece to make it as close to "round" as possible.

2. Use the mark made in Step 1 to center the faceplate onto the workpiece back, then attach it with wood screws that do not have tapered heads.

3. Thread the faceplate onto the spindle and tighten securely.

Using a Backing Block: If wood screws cannot be used to attach the faceplate to the workpiece, then use a backing block that is securely glued to the workpiece.

1. Make the backing block from a piece of scrap wood that is flat on both sides and free of knots or splits.

2. Locate and mark the center of both the workpiece and the backing block.

3. Drill a 1⁄4" hole completely through the center of the backing block.

4. Looking through the hole in the backing block to line it up with the center of the workpiece, glue and clamp the backing block to the workpiece.  Note: Allow the glue joint to completely cure according to the glue manufacturer's instructions.

5. Follow steps 1-2 in Attaching Faceplate to Spindle to attach the faceplate to the backing block.

Outboard turning:  a variation of faceplate turning and is usually done when stock diameter is greater than 12. Recommend a maximum diameter of 17 for outboard turning. The lathe setup at 90˚ for outboard turning uses the tool rest with the pivot arm extended.

Sanding or Finishing: The lathe can be used for finishing procedures after the turning operations are complete and before removing the workpiece from the lathe, such as sanding, polishing, and applying finishes by hand.  Note: When using the lathe to sand or finish the workpiece, remove the tool rest to prevent entanglement hazards. Use the slowest speed for safer control and better results.

TROUBLESHOOTING

TURNING

Symptom Possible Cause Possible Solution
Bad surface finish.

1. Wrong spindle speed.

 

2. Dull chisel or wrong chisel being used for the operation.

1. Use trial-and-error to find a better spindle speed.

2. Sharpen chisel or try a different chisel.

Inaccurate turning results from one end of the workpiece to the other 1. Headstock and tailstock are not properly aligned with each other. 1. Realign the tailstock to the headstock.
Can’t remove tapered tool from quill.

1. Quill has not retracted all the way back into the tailstock.

2. Debris was removed from taper before inserting into quill.

1. Turn the quill handwheel until it forces taper out of quill.

2. Always make sure that taper surfaces are clean.

Quill will not move forward into workpiece when handwheel is turned. 1.  Keyway not aligned with the quill lock lever. 1. Align the quill keyway with the quill lock lever and slightly tighten the lever to engage the keyway.

 

Motor and Electrical

Symptom Possible Cause Possible Solution
Motor will not start, or it growls on start up.

1. Switch safety key is removed.

2. Power supply fuse or circuit breaker has tripped.

 

 

3. Motor fan cover is dented, stopping the fan from being able to spin.

4. Paddle switch is broken or at fault.

 

 

5. Start capacitor is at fault.

6. Motor is at fault.

1. Replace switch safety key.

 

2. Disconnect power, and inspect circuit for electrical shorts and repair. Replace circuit breaker if it is old or has tripped many times.

3. Replace or adjust fan cover. Inspect motor fan and replace if damaged.

4. Disconnect power, and use an ohmmeter to check switch terminals for continuity, and replace switch if required.

5. Replace start capacitor.

6. Replace motor.

Fuses or circuit breakers trip open.

1. Short circuit in line cord or plug.

2. Short circuit in motor or loose connections.

3. Incorrect fuses or circuit breakers in power supply.

1. Short circuit in line cord or plug.

 

2. Short circuit in motor or loose connections.

3. Incorrect fuses or circuit breakers in power supply.

Vibration noise

while machine

is running; noise changes when speed is changed.

1. V-Belt cover loose.

 

 

 

 

 

2. V-Belt cover bent or dented and is making contact with the motor pulley or V-belt.

 

 

 

3. Bad spindle bearing(s).

1. Tighten the four screws that mount the V-belt cover; if necessary, install a soft, vibration dampening material between the V-belt cover and the headstock casting.

2. Remove V-belt cover and inspect the inside for dents, bends, or indications of rubbing. Tap out the dent with a rubber mallet, bend back into proper shape, or shim V-belt cover away from the motor pulley.

3. Replace spindle bearing(s).

Vibration noise

while machine

is running; noise remains constant when speed is changed.

1. Dented fan cover on motor.

 

2. Bad spindle bearing(s).

1. Replace or adjust fan cover. Inspect motor fan and replace if damaged.

2. Replace spindle bearing(s).

 

  END OF THE PROCEDURE