@Dave-R would it be the amount of segments in the corners?

I tried the skin technique , looks better , I have one little area that is showing through , but ill print it and see how it looks

@Dave-R yes joint P/P , not playing nicely , I select the whole surface but only a part of pulls out
, the inner skin seems to be coming through the outer one
I used the first curviloft , the head that's split in slices
ill try your idea with the lines

downpipe square to round.pdf

hi Dave
I've been trying what you said , and I'm getting some weird results with P/P. I also tried another way by selecting the outer circle and rectangle then curviloft, then the same with the inner circle and rectangle, but got a conflict on the inner and outer skins

downpipe square to round.skp
hi is there a simple way to make bits with a 1.2 mm wall thickness?

Overhang is 45 so no support needed, support at ideamaker gave me a gcode for xy and it worked good
To be honest the raise 3d machines can’t compete with the bambus

No, it seems to be in hidden sections, so would have to select every faucet on the plane and line
What I found is if I draw an arc from the top of the inner profile to the bottom, and do the helix , I can click on the curve and can delete it all ‍️
cant see the difference vwhy, but it works, the threads are great
what I found is a difference in tolerances, I printed 3 nuts with 0.1/15/2 offsets in petg and tpu, 0.1 was good in petg, but had to go to 0.2 for tpu
what a week of RND

How do I get rid of the grey spiral in the last picture?
)

Ah ok , I see what you mean, this is where ChatGPT was messing with me

What about tpi?

Ill check it out

These are what chat told me

Hi guys
Again thanks for all your help
Is there a chart you use to look up thread dimensions, pitch, tpi , crest etc
I was trying a m22 x 2.5 and got a bit confused on the chart I was following, so I asked ChatGPT
After 4 hours of me telling it, it was wrong, it finally agreed
I was drawing it in SU then asking it questions on the iPad
When I get home I’ll upload my figures and see what you think, the thread looks good on the screen, but that doesn’t mean it will fit
Thanks Dean

1CB2BC12-596F-4745-BC0F-C832939B95AE.mov

I finally got it to work , pictures to follow , thanks Guys

The base is where my finger is, so the layer lines go up from there

Ok I’ve managed a male and female thread on a 150mm diameter, with a 0.3 offset, . It’s very tight can wind it on for 2 threads , and that’s it. Tomorrow doing another female with an extra 0.3 clearance on all faces, so see how that goes. I think it’s the shrinkage on the printer that’s causing the problem
Thanks Guys for all your help