Purpose and Use of the Power Feed

Reducing the diameter of a long shaft or a long part can be a tedious task requiring a lot of turning on the feed screw. Obtaining a good finish on such a part requires slow, steady movement on the cutting tool, something hard to achieve when feeding the tool by hand. The Sherline power feed was developed to eliminate this problem. A clutch mechanism permits quick disengagement of the motor so that you can hand feed the cutter whenever you desire. The power feed is from right to left at a constant (nonadjustable) speed of approximately 1 inch per minute. This speed was carefully selected and is appropriate for virtually all jobs you might want to do, making an expensive variable speed control unnecessary.

It is important to realize that the feed is an independent drive with a constant speed; whereas the spindle speed can vary. If spindle RPM lowers, the cut becomes heavier, which in turn lowers spindle RPM even more. As you can see, the end result could bind up the machine and bring it to a stop. Always bear this in mind when using this unit. If spindle speed starts dropping from too heavy a cut, disengage the feed drive first, then either take a lighter cut (approximately .015" in aluminum) or speed up the motor.

Mounting Instructions

1. Remove the headstock, the flat head socket screw under the headstock, and the socket head cap screw under the base. (Note if there is a washer on this screw. Normally, on a 4000-series lathe there is no washer, while on a 4400-series lathe there is one washer. If there is a washer present, it needs to be in place when reinstalled.)

2. Grease the shaft with flats on both ends (P/N 1509) and slide it into the protruding lead screw support tube situated directly below the main spindle pulley. Ensure the end with a small flat enters first. Now slide the shaft with a single flat (P/N 1543) into the lead screw support tube. To guarantee that the shaft is "home", turn it one or two revolutions while applying gentle inward pressure to the end of the shaft. (See Figure 1.)

NOTE: If insertion or movement of the engagement lever is difficult, try loosening the two screws on the bottom of the machine that hold the bed to the base. Move the bed slightly until a good fit occurs.

FIGURE 1--Lead Screw engagement shafts in place inside Lead Screw Support Tube.

3. Replace screws removed in Step 1, making sure that the point of the cap screw underneath goes into the machined groove of the fixed shaft. Check that the shaft from Step 2 is free to rotate. If the shaft binds, first double check to make sure the end of the cap screw is registered in the groove of the fixed shaft and then add an extra washer under the screw head underneath if needed so the screw doesn’t go in quite as deep. Retighten the flat head socket screw in the bed and replace the headstock.

4. Pull out the black plug button on the side of the lathe base (below headstock) and slide the shaft of the engagement lever (P/N 1542) into the hole, handle facing upward. It may be necessary to rotate the shaft about 30° backwards and forwards to get it to engage properly.

5. Engage the shaft of the power feed unit and mount with bolts or sheet metal screws to the same base as the lathe so the shafts line up.

FIGURE 2--Power Feed installed on base.

Power Feed Parts List

No. Req.	Part No.	Description
1	15090	Sliding Shaft
1	15410	"O" Ring
1	15420	Engagement Lever
1	15430	Fixed Shaft
2	40510	Skt Hd Cap Screws, 10-32 x 3/8"
1	40520	Cup Point Set Screw, 10-32 x 3/16"
1	45090	Sheet Metal Screw, #4 x 1/4"
1	45100	Power Feed Bracket
1	45110	Power Feed Cord w/Switch (USA)*
1	45120	Power Feed Motor Case
1	45130	Power Feed Motor (110V.)
1	45140	Power Feed Coupler
1	40630	Power Cord (UK)*
1	40640	Power Cord (Europe)*
1	45250	Power Feed Motor (240V.)

*NOTE: U.S. models (P/N 3001) come with a US-type 3-prong grounded connector on the power cord, while U.K. and European models (P/N 3011) come with a raw wire lead ready for the installation of the appropriate connector used in the country of destination. Both models have an on/off switch as part of the power cord..