@Keith - I'm imagining the work I had multiplied by 4 - 2 for the length to cut and 2 for the thickness! Oh dear! Forget the gym, you will not need it

@ Leif - thanks a lot for the link :super: I was not aware of that one and it is always rewarding to see that my hobby is also interesting for somebody else. I was asked to make a tutorial elsewhere and it is available here:
http://maquetasenpapel.mforos.com/125693…rolos-em-papel/
It is all in Portuguese but the maths behind the rolled paper method are very simple and, hopefully, the pictures are helpful. I find the purpose-designed strip to get the desired shape good because it allows you to apply all the pressure needed to glue. There is not a hole in the middle, which could collapse while gluing and ruin all the work...
If that interests you, I made another spreadsheet to design paper strips to get wheel tyres. Hopefully, the first test will come this weekend, for the Lightning tyres

.
Needless to say, if someone wants a copy of the spreadsheets, just drop me a line

There is no secret behind them :rotwerd:
Rolled paper was also used by Fly Model, with a simpler shape, to model the gun muzzles, in it works pretty well here, too.