I am having quite the fun mounting some diamond wheels on face mill anvils and attacking some carbide on the old vmc with some stupid fusion trickery and thought about this while watching the thing run at 3mm per minute trying to plunge grind custom threading bits

Do you think f360 can be coaxed into doing a threadmilling operation where minor would get a bit smaller as you get farther from the cutting edge for some funky shop made hand taps?Can it even run trace with the point of a threadmill if i manage to model the relief on the helix divided by the flutes

Turbulent_Moose_69

3 | 14 hours ago

Wut

shoegazingpineapple [OP]

2 | 13 hours ago

Also read as, how the fuck do i grind taps on a 30 year old vmc without bespoke tool grinding cam suites or any more axis

Ab tools shop tour did me do it

BankBackground2496

1 | 4 hours ago

Grinding on a VMC?

Just because they did not include the tool cost in the quote .

Tell you boss its the quote guy’s problem and he’s welcome to have a go on the VMC.

shoegazingpineapple [OP]

1 | 3 hours ago

This is my fuckaround machine, there is neither a boss nor a quote guy that made this happen,

Cheer up we are just picking brains

HuubBuis

1 | 13 hours ago

I have the same wish but my CAD (FreeCAD) can’t do it. You need a tapered thread but also clearance. It is not just a spiral cut.

Having said this made me thinking.I do turn taps on the CNC lathe. If I omit grinding the flutes, it is a well performing form tap that does a great job in tapping wood.On the lathe I generate the clearance by offsetting the tap in the chuck. The same procedure could be done on the CNC router by changing the position (origin) of the tool.

Have a look at this old video where I show how to turn taps on the (CNC) lathe.

shoegazingpineapple [OP]

1 | 13 hours ago

It is still a 3d arc if i am not mistaken, i would generate the od clearance by milling it on the od behind the teeth but the threads get another axis on top of that and i cant write that, maybe ai can be coaxed into making a simple excel script generating some single line 3d arcs on every segment

On a lathe you would run a similar path if you have a c axis unlike the people who like making hexagons on 2 axis c axis capablr lathes but a carbide threading tool might not like it very much

I dunno something like a simple z0 x5 c0 to z-.33 x4.8 c110 would do a single teeth on an already fluted blank 10degrees for the flute and resetting back to x5 for the next cut

BankBackground2496

1 | 4 hours ago

I had used FreeCAD in my previous job. Sad state of affairs when you turn into MacGyver.

HuubBuis

1 | 3 hours ago

I am using FreeCAD for some years now. I takes some time (and frustration) to get around the CAM bugs and I would not recommend it for general professional use. Using it for 3D printing and 2.5D milling is OK.Nevertheless, FreeCAD is fast improving and the 26.3RC2 release is a great improvement. It is getting close to “fit for professional” use where lower costs are more important than extended features.

Big-Web-483

1 | 13 hours ago

You really need 5 axis to cut a tap but if you can get a wheel dressed right and tip a fourth at the pitch angle. Spin the fourth and move the Z. You can’t get the right relief on the grind to do it with three axis.

shoegazingpineapple [OP]

1 | 12 hours ago

I think threadmills circumvent the pitch tilt via reducing the thread angle a bit or they would cut above 60 degree threads maybee?

Big-Web-483

1 | 11 hours ago

Your on the right track, I made the assumption that OP was going to dress the wheel and grind the thread by on a vertical mill. Getting the profile dressed correct on the wheel to get the thread profile correct would be the challenge. I’m not saying it couldn’t be done but I believe it is an involute profile and that would be the hard part.

I believe in the hard part. I milled threaded slots that worked and gaged!

shoegazingpineapple [OP]

1 | 3 hours ago

Didnt even think about the involute part, smart stuff

TriXandApple

2 | 13 hours ago

Yes, obviously, use a trace.

Programming form relieved shop made taps via thread milling?