5 axis toolpath help

[gcode]

Check out the attached file (zipped MC2019)

I am machining a ID  6 lead 1P Acme thread

A 1"pitch 6 lead thread means the actual pitch is 1 thread per 6"

This toolpath is the roughing path to rough the C/L of the thread with a 5/16 wheel cutter

The machine is an Okuma 5axis Lathe

The green line represents the C/L of the part and the C/L of the C axis spindle

The red line is the perfect world B axis tilt... 9.405°  

I have done parts like this in the past using this approach and it worked well.

This time the ID is smaller and the pitch of the thread much steeper.

I think this will work OK, but I'm getting ±.003° flutter in the B axis output

I'd like a toolpath that locked the B axis at 9.405 and rotated the part around C (the green line)

and I can't get one to work.

I think the ideal toolpath would just use the curve as drive geometry

Does anyone have any ideas?

 

1P Acme 6 lead.zip

[gcode]

Here is a screen shot of this part on our Postability machine simulation to give you an idea of what's happening

 

 

[Manofwar]

Like this? 

Limits.zip

 

I'm using a conical limit switch down the center of the part with the setting of the upper and lower limit at 9.405 so it locks the B axis and C is still allowed to move.

[gcode]

3 minutes ago, Manofwar said:

Like this? 

Limits.zip

Yes... exactly like that.

I tried that approach, but chained the green line in the wrong direction and the toolpath would not regen

 

Thank you

[gcode]

We finally got some machine time and ran this part last week

As always the Okuma VTM was superb. 

The tools were a Ø4" x .312W slotting mill for roughing and a Ø4" x .75W slab mill ground to make a 1P Acme form tool

Despite the 14" long C5 Capto stack for arbors, the Okuma purred like a kitten.

The posted code was flawless and the finished part looks great.

We haven't been able to gage it yet though.

The "gage" is a 60 year old 2000 pound shaft with 60 years worth of rust and battle damage.

Our part is to print but will not fit on the beat up shaft without damaging critical ID's

The customer is still deciding what they want to do about that.