MODEL NUMBERS 612 & 618

Here is a list of the materials and tools you’ll need. We suggest that you check it carefully and follow its recommendations; they will help you do the job successfully. Dirt is the biggest enemy of lathe accuracy. Guard against it. Handle each part with care and be orderly. It will save you time and safeguard the accuracy bui1t into your lathe.

1. A large clean cloth or sheet of paper, about newspaper size. Place this over the top of your workbench and lay each part on this as you take it from the lathe. Keep the parts in the order they are removed.

2. A clean can partly filled with a good clean grease solvent. It is better to spend a few extra minutes making certain that each part is clean than it is to ruin an expensive unit because of dirt.

3. A small box or can to contain the various small parts such as set screws and keys. Be sure that you do not lose any of them. Each part, no matter how small, is important and has a reason for being on your lathe.

4. Have plenty of clean rags handy for wiping parts. Be sure that all the old oil is removed from each unit.

5. Two squares of clean cloth or paper to wrap around the spindle roller bearings. These should be wrapped as soon as they are taken from the lathe. Be especially careful with these units. They may roll off your bench and be ruined.

6. A can of fresh S.A.E. #10 oil.

8.     A piece of broomstick about 10" long. This is to be used for removing the spindle. Never strike any lathe part directly with a metal hammer. The slightest distortion will ruin the accuracy of a precision part.

9. A pair of pliers for removing keys.

10. A small punch for driving out pins, about 1/8" diameter.

11. A round nose punch, about 5/16" x 8". This is to drive out long shafts as directed.

Figure 1

13. A small machinist hammer.

14. A small fine flat file for removing burrs on shafts. Most of these will be caused by set screws.

15. Arrange all of your tools within easy reach.

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Figure 2

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1. Loosen, by turning counterclockwise, set screws A & B in collars C & D.

2. Using the small 1/6" punch and hammer, drive out the groove pin E. This pin locks the shift lever collar F to shaft G, and should be in a vertical position to be removed. Be careful not to damage the edges of the pin or hole.

3. Place the large punch squarely against the end of the shaft G drive in direction as indicated by arrow. As the shaft moves through the shift collar F, the plunger and spring H will be released. Be careful not to lose them; put them in your small parts box.

4. Continue to drive shaft G out. As it passes through the collars, the back gears may be removed. Lay them in order.

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1. Loosen set screws I, J and K by turning counterclockwise.

2. Underneath set screw I is a lead thread protector which prevents the hardened set screw from jamming the spindle threads. It is not necessary to remove this protector but do not lose it.

3. Remove threaded collar L by turning counterclockwise (facing rear of spindle).

4. Slide gear M off the spindle. If it is tight and sticks, tap it gently with the broomstick and hammer. Do not, under any circumstances, strike the gear directly with a metal tool.

5. Using a pair of pliers, remove key N by pulling upward on it. If it is tight and sticks it may be "rocked" out by driving down on one end with the small punch and hammer.

6. Remove collar O by sliding it toward the left end of the spindle. It may be necessary to lightly file the top of the keyway.

7. Place the two hardwood wedges in positions P and Q, tapping them until they are securely wedged. They

will occupy the space between gear R and the headstock casting.

8. Place the piece of broomstick at the left end of spindle S and drive in direction indicated by arrow until key T emerges from gear R.

9. Remove wedges and rotate spindle until key T lines up with slot at top of dust collar U. This slot is not shown in the illustration.

10. Drive spindle entirely out of headstock in direction of arrow. As the broomstick follows the spindle it will serve as a temporary spindle, and catch the rear roller bearing, collar, pulley and gear. BE SURE TO CATCH THE SPINDLE AS IT IS RELEASED FROM THE HEADSTOCK. THE SLIGHTEST DISTORTION OF THIS PART WILL RUIN THE ACCURACY OF THE LATHE. The spindle should be carefully wrapped and placed on bench so it will not roll off.

11. Pull broomstick out, remove the parts as they are released and lay them in order on your bench. The rear roller bearing should also be removed and carefully wrapped. The front spindle bearing is pressed on the spindle and should not be removed unless new bearings or spindle are being installed.

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1. Clean all parts thoroughly. The Timken bearings should be cleaned first to eliminate any possibility of foreign particles in the grease solvent getting into and later damaging them.

2. Lightly file all burrs from both the spindle and back gear shaft. These burrs are usually caused by set screws or upset keyway shoulders. File in a circular motion, rotating the shaft in one hand and moving the fi1e in the opposite direction. This avoids flat spots on the shaft. Reclean parts after filing.

3. To reassemble, reverse the above procedures. Be sure belt is in position. In driving the spindle into the headstock, use the palm of your hand as much as possible to avoid any possibility of damaging the precision surfaces of the spindle nose. Use the photo as a guide, making sure that all parts are installed in their proper positions.

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1. Tighten collar L by turning clockwise until all lateral (end) and radial (side) play has been removed from the spindle. An easy way to check for this play is to tap the spindle back and forth laterally with the palms of the hands. The spindle should rotate freely.

2. Pre-load spindle bearings by continuing to tighten the threaded collar L approximately 1/16 turn or the

equivalent of two spindle gear teeth. There should be a slight drag felt as the spindle is rotated by hand. This is important because as the spindle and bearings warm up, the spindle expands laterally approximately .002".

3. Insert the lead thread protector and set screw I and tighten set screw. This locks collar L to the spindle and holds the adjustment in place.

4. Insert a screwdriver between collar V and the edge of headstock. Crowding the collar will slide the entire pulley and gear assembly until the pulley is against shoulder W on the lathe spindle. Tighten set screw J to lock collar V and hold the pulley in the correct position.

5. Slide gear R toward the spindle pulley until the clearance between these two parts is approximately .004", or just enough to allow the pulley to rotate freely. Tighten set screw X.

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1. Shift back gear X until it lines up with spindle gear R, and then lock collar D by tightening set screw B.

2. Crowd collar C against headstock casting and tighten set screw A. The back gears will then be locked in the correct position.

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1. Lubricate spindle bearings with fresh S.A.E. #10 motor oil.

2. Remove oil reservoir screw Y and lubricate spindle pulley with S.A.E. #10 motor oil.

3. Remove oil reservoir screw Z and lubricate back gear shaft and bearings with S.A.E. #10 motor oil.

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