How to cut something round on a vertical mill?

[Dabbler]

@great white Thre are so many techniques that you might use, but showing a quick sketch (even in paint) would really help to focus our efforts. Some of the techniques would be totally wrong for some shapes, etc.

 

[great white]

I’ll get a quick photchop up in the morning.

tried both conventional and climb milling. Neither worked, both eventually jammed the RT.

 

[pontiac428]

So far, following everybody's helpful input, the image in my head of what you are making is something like one of these parts:

 

[stupoty]

So you put the square end in your lathe 4 jaw chuck, make the end that sticks out round. Then move to the mill, hold the round end in the mill vise with V blocks or a collet block, or a spin indexer, or whatever you can figure out, mill a side of the square, and rotate as needed for the other sides.

Is the square bit bigger than the round bit or the other way round ?

If the square is larger you could make the square bit in a four jaw also as you might square a block of stock on a lathe.



Stu

 

[Firstram]

So far, following everybody's helpful input, the image in my head of what you are making is something like one of these parts:

View attachment 413937

I saw one of those at a yard sale for $2, I thought it was broken.

 

[Janderso]

So far, following everybody's helpful input, the image in my head of what you are making is something like one of these parts:

View attachment 413937

That’s really funny

 

[MrWhoopee]

So far, following everybody's helpful input, the image in my head of what you are making is something like one of these parts:

View attachment 413937

First semester project. Separates the engineering students from those with actual potential.

 

[great white]

Here's a quick doodle of the part shape:








The thickness is roughly 1.5".

 

[MrWhoopee]

What is the dimension and tolerance of the radius?

 

[great white]

What is the dimension and tolerance of the radius?

it's a plinth to mount a ball cuter, tolerance isn't overly important on the outside dimensions other than parallel top and bottom surfaces, the center height (thickness) and the bore where it will mount to my Atlas cross slide. The radius on the forward edge is the radius of the ball cutter mount.

For equipment I have to use: Atlas TH42 lathe and a CX600 (same as G0704) Vertical mill. Mostly the standard stuff like the mill vise, end mills, etc.

The 3" rotary table is essentially out of the question as it just seems to be cheap and has waaay too much backlash, no matter what I adjust or shim.

Of course, I also have the usual metal tools like metal saw (portaband) grinders, files, etc.

I also can't quite figure out how o cut the 45's on the rear edge. My mill vice is a fixed model, no swivel base. I suppose I might be able to secure the vice on a 45 on the table maybe?