I encounter every now and then a strange deviation bug in Rebuild.
And here is a simple way to recreate it.
Make a helix with this string
! _Helix w0 w0,0,23 Mode=Turns Turns=1 12 12 Enter
Run Rebuild with these settings:
point count = 12 and degree = 2
It works fine in degree 1 and degree 3, but degree 2 falsely gives a max deviation of 21.2919 units.
Hei Jørgen -
(ikke helt ferdig for i dag allikevel …)
(8.13.24268.02002, 2024-09-24)
One of these days I’ll need to take a break to see what’s keeping you stuck in Rhino 7.
-wim
Absolutely! And luckily it isn’t a long walk either 
Hopefully the bugs are gone too.
But check this out, this is in R8:
I guess I’ll need t hat curve.
The one that gets created with the Helix w0 w0,0,23 Mode=Turns Turns=1 12 12 Enter macro has 39 points; yours has 27.
Also, if you are running a slightly older version of Rhino 8, the following bug from 2005 has been fixed in the meanwhile and that could also explain the difference - RH-1898 Something wrong in deviation
-wim
That I did, I saw it updated when I closed it on my home computer last night, here at the office it works like on your machine, with identical deviation.
Why the older version of R8 created a different helix is also interesting, on the new build it is the same as yours with 39 points. So something has changed to the better 
