Non geared rotary table

[jwmay]

Next project that's been following me around for years is this rotary table, based off of Harold Halls design. The main body of it was made from a very large chunk of what I think is D2. It was miserable to machine. Burnt up a half dozen HSS edges before I went to carbide. At any rate, when I got just about to what you're looking at, I messed something up and stuck all this in a drawer.
I decided today, that it's waited long enough. So after some studying of the drawings, and watching the YouTube video, and searching for the book I got the plans from, I realized that I also missed a three hole pattern in the center of the table itself. So it's set up in the mill ready for me to fix the first overlooked mistake I made all those years ago.
My plan is to drill and tap three or four holes in this to bolt an aluminum plate with a grid of threaded holes in it. I say three or four holes, because I expect this metal to be completely disagreeable. I should mention that Mr. Hall warned against using unknown metals while learning to machine. And so, this is my just desserts.

 

[jwmay]

If you're curious, this is the last part I failed to machine correctly. This is what landed the whole project in a drawer for years...lol

 

[markba633csi]

Yes, mystery metal can be just awful to work with, even if it saves money it wastes time

 

[jwmay]

Here is the table mine is modeled after. Tee slots aren't really an option due to the miserable mystery metal I used.

 

[woodchucker]

mistakes are normal. how you fix them is what makes you a craftsman.
sometimes I do the same, and put the project away for a while..
glad you picked it up again. Most of the time you can fix it.

I've plugged holes, and you can't see them, I've filled slots , by keying them as a t slot.. And sometimes, I've left the scars as a reminder, or not worth worry about.

 

[jwmay]

Well wouldn't you know it! I messed it up again! Luckily, a shim saved the day.
Another thing I tried to do, but didn't quite get right was this. I attempted to just countersink the bolt pattern instead of counter boring. After realizing it was going to fail, I counter bored the other two. So it doesn't look very nice, but I'm ok with it.
Lastly, I needed to make a space for a tapered nut to fit into the slot at the base. There will be a couple hard stops that get mounted here. I now have to make the tapered nuts.