Lathe square tool post assembly drawing [Revel pos documentation, manuals]

Fixture for Milling Ted's Toolholders on your Lathe

By Ryan Flaherty

Here is a fixture I made to mill the toolholders for TNMP inserts described by E. M. (Ted) Edwards. (See: Ted Edwards)
With no rotary table or mill, I made it all on the lathe and drill press.

The fixture consists of 3 pieces: 1) a Clamp Rail by which to mount it in your toolpost; 2) a 5 * Wedge Block to establish the nose angle; and 3) the Vise Block to hold your work (the toolholder you are milling). See figure: Ready.gif.

Stock: Clamp Rail - 1/2" x 1/2" x 3" - 1/2" keystock is good

Wedge Block - 3/4" x 2-1/2" x 3-1/2"

Vise Block - 1" x 2" x 3"

Construction:

See drawings: Wedge.gif & Vise.gif.

First you'll want to true up the Blocks and Rail ends by facing in 4-jaw chuck or face milling w/ flycutter. At bare minimum the back (bottom in drawings) faces of both blocks need to be machined or filed flat & deburred.

Now layout the Clamp Rail and drill 1/8" pilots in all 4 holes. Use the Rail as a guide to drill pilots in Vise Block at locations marked "V". Do the same on the Wedge at "C" & "M". All 4 holes in Wedge are drilled out to tap size (no. 7, or 13/64) and Tapped 1/4-20. Drill Clamp Rail holes to 1/4" and countersink.

***Possible Alteration*** You may have to adjust the position of holes "M" to the height of your toolpost. You want the top edge nearly 1-1/2" above lathe center so a 3" flycutter will just cut it (this will help to keep the flycutter from "pulling in" the work by climb milling). If you have a milling attachment, you may be able to relocate hole "M" to line up with a "C", and eliminate the other "M" hole, then set the height via vertical slide.

Mount Clamp Rail to back face of Wedge Block using 1/4-20 x 1" flathead screws into holes "M". Mount assembly in toolpost using the Clamp Rail. Now set over the compound 5 * from parallel to the cross-slide. See figure: Setup-1.gif. The top end (w/ holes "C") should be farther from the headstock, as it will be the "thick" end of the wedge.

Mill off the face of Wedge Block until it is just flat end to end, forming a 5 * wedge. Remove work & debur. Layout pivot hole "P" on 5* face of wedge. Drill 1/8" pilot using Vise Block as guide. Drill out holes "V" in Vise and "P" in Wedge to tap size, Tap 1/4-20.

Move the Clamp Rail to back face of Vise Block, mounting to holes "V". Set compound to 0* so toolpost is parallel to cross-slide, mount Vise Block in toolpost using Clamp Rail. You will have to shim up the Rail or whole turret to center the slot, or again, you could use a milling attachment. Mill slot to 9/16" wide by 1/2" deep. Be sure slot is centered on holes "V". See figure : Setup-2.gif.