Hi Michael,

>>>it does appear to be related to very small differences in the tangents (like around 0.035 degrees), which get magnified to a certain extent during offset

Is that then just a connection problem on the offset curve (just interested)?

>>>Do you happen to have any earlier versions of this before the curve filleting went in place?

No, as you will see, I was very early in construction at that point.

>>>Also, are you able to finish this model now, or do you need help tuning up this particular case?

Certainly no problem from me, I did find a little problem, but whatever, I will still finish. I was only trying to show a problem I found.

I will certainly look more at this, more as a possible problem for others (it will probably show again~ possibly from a user who does not know what to look for) and not everyone will look back as I do.

Michael,
Please, I am not complaining, I know such as deviant as "like around 0.035 degrees" is not a problem, but knock on effects such as ability to sweep/merge can/will fail (it is why I backtracked~ then posted).

Regards,
Steve