Hi Andrei,

> Never know about this, now I clear undertand why you use to be to advise to small down object to make join.
> A lot of things are now clear for me... Thank you very much for explonation!

Things are slightly more complex than what I wrote - the join operation does use a "relative tolerance" so if the bounding box around the things being joined is very large or very small it uses a scaled value. But it does target 0.005 units for the max join if the object is between 1 and 50 units in size (measured by bounding box diagonal).


> My question is what happen with this small segment when we small down object and join it and
> then scale it up. This segment will just deasapere?

It probably won't disappear, it is possible for that to happen but an edge has to be squeezed down to a very small size for it to actually go away through a join.

What exactly will happen kind of depends on how the edges relate to one another - but it is possible for the ends of the small edge to divide the larger one up into pieces and then the pieces get joined.

- Michael