3rotor wrote:
I just thumb-sucked those figures and then started to work from there...
Best way! My first 2 tubes I rolled looked to tight so I did a second 2 and rounded them off to a even number (290mm underbelly clearance when standing vertical to the floor).
Then did the lower 2 to suit and also rounded it off to an even number (240mm).
The purchased tubes are 6 meters long so cut in half entirely determined the length of the car and rounded off numbers determined the shape, then rounded off the 3 major height points of the lower and upper tubes such as say 400, 700 and 600mm's (example only) for the front, middle and rear points of the upper tube - how can you go wrong? Makes it easier to get side to side equalisation too.
My builds are not complicated and every tube is rounded off to even numbers where possible as are angles.
Big tip for those who want to roll your own joints, errr tubes, weld a wide crossbar say 1 meter long on one end (your handlebars) and as it goes through the rollers and up the other side, steer the far end of the tube up along a verticle line on the wall, this is by far the best way I have found to combat tube twisting/screwing.