Ideas on a method/s to machine this ?

[Ken_Shea]

Do not have a 4th axis on the mill, any ideas on how you might go about machining the helix?

Ken


It is about 1" in length and 7/8" in diameter.

[garyphansen]

That is not just a simple helix, it is a cylindrical cam. Looks like a job for a pantograph or CNC to me! Gary P. Hansen

[Bguns]

Break Cam Path up into as many x or y movements needed for application (say 1 x or y move per Degree of rotation), and cut Cam path Manually, one small bit at a time... Smooth out with file if needed...

Old School...

New School, have someone CNC it for you...

[Evan]

First question is what are the tolerances?

Also, it doesn't look like a helix. What is the side view?

[John Stevenson]

If you can get away with a helix then mount the job up on a mandrel and on an extension to the mandrel weld two washers, each with 4 tapped holes in and a space about 3/4" between the washers. Weld the washers so the 4 holes are equally offset in each before you weld the last washer on drop a large washer with a sloppy bore between.

Now by using 8 push pull screws you can make this washer follow a helix to the extent of the spacing.

Set a follower up from the toolpost or saddle, whatever is most convenient and run at low speed.
The wobble washer will pull and push the saddle and you can apply a cut.

That's how we used to machine the helix groove in Pilgrim oil pumps.
I can do a sketch if needed.

.

[Ken_Shea]

Gary and Bguns, thanks for the input, was hoping to come up with a solution using the tools on hand, have a CNC mill but no CNC controlled 4th, breaking it up into a bunch of coordinates was a method I was not wanting to do, would work but very slow and prone to mistakes.

John, let me read your suggestion a few more time to see if I can visualize what you are doing, if not then a sketch woul be helpful.

Evan,
Tolerances show +/- .005 , pretty loose.

Side View:

[barts]

If you can mount a suitable end mill on a powered horizontal spindle on the table, put the part on a mandrel in the CNC spindle. You use the X and Z axis to machine the part to whatever profile you want. This assumes you have servo control of the motor spindle - perhaps not a good assumption on on second thought (hence the edit).

- Bart

[daveo]

I have an extra one of those, made on a cnc mill. For the Rgg gun right?

[Ken_Shea]

Daveo,

A close cousin, for the D&E version.


Ken

[daveo]

I gave up on mine, had a guy make a couple up. Very tough to make