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I thought I would post an update.

My goal was to make a metal lathe tool grinding jig that was adjustable for angles in all three axis.
As you have seen in this thread metal lathe tools have been ground successfully on high speed grinders for generations with no problem.

I just wanted a bit more accuracy and buying a low speed grinder is a perfect excuse for making this jig.

Here is an overview.

This is a working "proof of concept" prototype.  I still need to clean off all the layout dye, chamfer edges, install the adjustable angle indicators and paint.

This is from above.  You can see the left and right tool clamps and the horizontal angle scale.



Looking from the front you can see the vertical angle scale.



To fit over the rest rod I drilled a hole in some scrap Delron.



The first step in grinding a metal lathe tool is to create the "Side Cut Angle"  The angle for the Side Cut Angle is comprised of two axis. It is ground on the right side of the grinding wheel.
The horizontal scale is set to 10¯ deg°and the vertical is set to 10°.



Second, you grind the "End Cut Angle"  This is also two axis with the approach to the face of the wheel being one angle of 12° and the horizontal scale set to 20°.  The vertical scale is set to 0°.
This setting gives a 110° single point relief.



Finally the Back and Side Rake Angles are ground.  This is done on the left side of the wheel.
This lathe tool is specifically for use on Delron so the Back Rake Angle is set on the Horizontal scale at 26°.  The vertical scale is set to 10°.



Here is a close up of the finished lathe tool.



Not too bad a cut.



The reason I chose to grind this particular tool first is that my next project has parts made from Delron.  Delron requires very sharp edges and larger Back Rake Angles than tools used to cut steel.   I thought a Delron cutting tool would be a good first attempt.

I have CBN wheels inbound from Australia and that should be just a bit better than always facing the right and left sides of the standard grinding wheel.

I am proceeding with my dual angle jig.

While it has been the practice when grinding lathe tooling on a high speed grinder to grind the Back Rake with the tool in the direction shown in fig. 7 -




I prefer to grind the back rake with the tool held longwise to the stone, along the side of the stone.  It is more secure, the angle is more accurate, and the grinding process is much safer.

This requires two angles along with the horizontal angle of the tool to the face of the stone.  So three angles total.



Here is a jig made by another person that may explain the concept of where I am trying to go.

Rick,

While I appreciate the idea I really do not think the DBS will work for what I need.

A lathe tool is ground using compound angles.  In all three axis at the same time.

You cannot view this attachment.

So I would need a surface adjustable in the Y and Z axis with the angle to the stone as the X axis.

I do not have a DBS as I use a drill doctor for drill bits.

I was not planning on using any of the existing jigs but developing a new, stand-alone jig.  Drilling the holes for the slide is the easy part.

I spent part of yesterday doing notebook pencil sketches.  Size and weight are the primary factor right now.

I also would prefer engraved degree markings and a rotary table makes those easy.

Progress reports to come as I have them.  Right now first project on the lathe are tools for my wife's weaving loom.

Well, I have a mill and a rotary table.

I think I will work on a jig adjustable up to 20 degrees either side, in two axis.  The third axis will be to the wheel.

I also have a BGM 100 which I will mount to use the side of the diamond wheel with the same jig.

I have other projects ahead of this so give me a week or two.  Photos to follow.

I have been reading through old posts trying to find the answer to a question.

Does anyone know of a jig that will handle the grinding of metal lathe tooling?

The most basic single point cutter requires at least 6 different angles on the faces of a blank of high speed steel.
Traditionally this was done on a high speed grinder by hand.  Getting precision angles requires practice, experience and patience.  I can do it but I bought my Tormek specifically to help me achieve higher accuracy with the more complex angles.

At a minimum I would need a jig that is adjustable in both the horizontal and vertical along with the angle to the faces of the diamond stone.

Does anyone know of a jig or plans for one.