Re. your "It seems a good point to fabricate a mini tube bender" and "mag articles on the subject but I do not subscribe".
You could wose than look at David Carpenter's FREE ! website **LINK**
There have been two designs over the years, the first being **LINK**
But the easier one to build, producing accurate, tight curves in small Cu pipes was published by "Artisan". Unfortunately David seems to have moved the article to a DVD now (requiring payment) but I have the pdf and this image is from that, hopefully not infringing copyright:-

This is mine and have always felt it worth the effort of making in that my pet aversion is seeing poorly-formed bends in wavy pipes on otherwise excellent models.
