Tapered Helix, Is it Possible?

[bgmnn]

Can a helix be programmed, conversationally, to cut a taper along its length?

I have a 21 degree angle to cut in a bore.
Have tried to program the helix with taper, but am getting errors.

Start dia is 3.155.
Finish diameter is 3.000.
Z length is approx .2053.
Center X0,Y0.

Hurco KM5P, Ultimax software.

Thanks in advance,

Mike

[bloke]

If you have the 3D mould option, you can do what you are attempting but running down the angle in concentric ever decreasing circle moves.
Without it, you'll be limited to an angled line move rotated about centre.

[bgmnn]

No mold software, just Max 32.
Does that mean I could not thread mill tapered pipe threads either with conversational programming?

Thanks for your help, Bloke.

[bgmnn]

Is there a simple format to program the desired path on the NC side?
Is parametric programming possible?

[gthlm]

Mike, unfortunately there is no easy way to do what you want to do either in conversational or nc. Standard gcode has no provision for full tapered helices (you are normally limited to approximations with single quadrant tapered helical moves - this is how tapered threadmill operations are programmed in gcode - but that is still a very large program that you would not want to hand code) and there is no macro/parametric/procedural programming facility on the older ultimax controls.

Bloke's suggestion of a XZ line in a rotate pattern around the centre is a good one and will work, albeit slowly and you may not be satisfied with the finish/accuracy.

If you are stuck I can rattle up a quick nc program for you in featurecam. It'll be for the ultimax 2 specifically but I think the nc format is essentially identical, and it will be in metric as my post processor doesn't do inches. I'd need the material, details of the tool you want to use and the surface finish you require.

Gregor

[bgmnn]

Thanks for the offer Gregor.

The part is a bushing. The angle is a dust seal surface, that is above a tapered bearing race bore.

I have decided turn the angle in the bushing on the lathe, install the bushing, and bore the bearing race bore to size after installation.

The seal is quite forgiving and will seal with the slight discrepancies anticipated.

Thanks to all for your suggestions and offers.


Mike