[How-To] Verify gauge blocks for mt3 shank grind

[Cadillac]

Looking for a confirmation on my gauge block setup. I’m making some mt3 tailstock shanks. I’ve already cut the taper on the shanks on the lathe. I used a new mt3 shank and dialed in the compound off that. I left acouple thou. for grinding.
I have a suburban master grind fixture mounted on a sine fixture. The length of fixture is 5” on center. I have come up with a .130 stack of gauge blocks to get my desired angle for grinding a mt3 shank. Does that sound right?
Setting up on the surface plate shows like a .001 difference from lrg end to small. This could be because of my setup on the compound idk? If .130 is that stack than I’ll just grind it but I want to make sure before I do. Have alittle bit of time in it to scrape it. Any help would be appreciated thanks.

 

[benmychree]

Add to that setup for final proof would be a ring gage to prove the finished taper.

 

[Cadillac]

If I had one but I don’t. The plan was to grind and then blue to my tailstock, a new reducing sleeve, and I have a ground round piece with a #3 internal. I think it was used to grind centers on a tool grinder. I had gotten it in a box of other grinding stuff in a auction.

 

[benmychree]

If I had one but I don’t. The plan was to grind and then blue to my tailstock, a new reducing sleeve, and I have a ground round piece with a #3 internal. I think it was used to grind centers on a tool grinder. I had gotten it in a box of other grinding stuff in a auction.

That will work fine.

 

[Technical Ted]

If you are primarily going to use it in one particular female socket, I would suggest using that for the gage, since that's where it will be living.

Not all MT sockets are created equal...

Ted

 

[T. J.]

Looking at from a Morse Taper spec chart I found online, MT3 has an angle from centerline of 1.4377. Calculating the gauge block stack for a 5" sine bar, I get a stack of 0.1254"