A Work Head For The T&c Grinder

[Mark_f]

I am still in the process of making fixtures for the T&C grinder. Building the grinder is only half the project. You then need various fixtures to properly present the work to the grinding wheel. It is hard to decide which ones to make first , so I am making them as I need them.
I now need a work head to hold end mills while sharpening the ends of the end mill. I could put them in the air bearing and change the wheel angle for every cut. But then I have to line up the wheel again to grind tools. Having an easily adjusted work head would be less setting up and much faster. I am starting with the spindle because by making it first , I can bore the head to fit the spindle. This is easier. If I bore the head to 1.625" like I want , I have to hit the spindle dimension and there are about 5 hours in making this spindle. I would hate to mess it up and start over ( besides , I only have enough material to make it once).
I used my new steady rest to hold the spindle steady while I bore it.
I bore to 1.252" for a nice slip fit on a 5C collet. I also cut the 10 degree angle for the collet. I finished th OD for about 1 1/2" on the end.

By doing all this in the same setup, I know everything is concentric.

I chucked the finished end in the 4 jaw chuck , indicated within .0005" and put a center in the other end to turn the spindle OD.

I made a center plug from a piece of aluminum to support this end.

This is the finished spindle. I was having trouble getting a decent finish on this mystery metal and wound up .008" smaller than intended. THAT is why I made the spindle first. Boring the body to fit is easy, but I could still screw it up .

This chunk of cast iron wil transform into the work head body.

 

[brino]

Mark,
I'm "watching".
Thaks for sharing the build!
-brino

 

[Mark_f]

I began machining the body for the work head.
I machined the one side down to a square. Now I'm turning it to make the mount for the base.

I turned it an center drilled the mounting bolt hole. I also marked 30 - 0 - 30 degree marks for setting the angle. All this had to be done in the same setup to keep everything concentric.

Next will be to turn the ends round and bore for the spindle.

 

[Mark_f]

I used the 4 jaw chuck to turn the ends round. Then starte to bore for the spindle.



After getting the bore to size , I finished the OD and face of the front end. I intentionally set this end up last because it is very important that the face be aware with the bore for the spindle to ride against without binding when rotated. The rear end was bored and is very close to square. I will scrape this face square at assembly.

The spindle is a perfect fit. The bore is so close , there is no play and there is a very slight drag when rotating the spindle, yet it does rotate easily. This was my goal here.

I now have to design the rear end. There has to be a collar , but I need to incorporate indexing into it. I don't know how I will do it yet.