rotary tables

[jct842]

After over a year of wishing I bid and got a rotary table coming for my micro mill. a 4" with probably a 36 to 1 ratio. I also ordered a 1/2" piece of 6061 to make the backing plate for a 3" 4 jaw I can dedicate to it. I recently bought a 4" 4 jaw for my 7x12 lathe. I have made some pellet guns and have had a lot of trouble to align 3-4 mounting holes on the gas valve to the gas tube. My alignment problems should be over with the new purchase. I have spent hours and days drooling over the engines here and will be building one soon.
I would appreciate any comments on making my backing plate. what I have coming is a 5x5 x 1/2" plate. to temp clamp to the table to get the 4 holes to bolt into the t-nuts is bothering me. Thanks John

 

[Mainer]

Although it's certainly possible, 36:1 would be an unusual ratio for a rotary table. Is it possibly 40:1? Just verify the ratio before you start using the r/t!

I am likewise unsure of what information you're looking for. Can you be more specific, or is it a case of, "If I could be more specific, I wouldn't need to ask the question!"?

 

[jct842]

I think I understand now on the plate, but the big problem is the table is tied up in shipping with the snow and all. In looking over the 4 jaw I have I see how the center has to be on the adapter plate. when I get the table in my hands I should be ok. I just jumped the gun and with out having all the pieces in my hand I should have waited to ask. Sorry for the bother, and thanks for trying. John

 

[doubletop]

.........or get a front mounting chuck and then it's just a case of making some T slot nuts

This one is branded HBM but I got exactly the same thing direct from Vertex

Pete

 

[jct842]

I got the table and got it fitted with an adapter plate to take 3 and 4 jaw 3" chucks. table is a 4 inch so there is 1/2" of room on the outside of chucks to screw down the plate. I see that it would be more convenient to be able to use a front mounted chuck and save the space an adapter plate takes up but I used what I have. They sent a clamping kit with it also. It is a 36 to one drive ratio. It has 10 degrees on the hand wheel and takes 36 turns for one rev. It cost $70 shipped. To test it I milled 7 sides over a hex bolt head. it came out a little smaller than the 6 sides, but even. I will go to hard ware store and ask them to find me a wrench for it! : John