So, after the first couple of attempts at making the exhaust, I realised I was designing and printing myself into a corner, so I decided not to print anything else until I had a full design I trusted, to the dimensions I wanted, and this is it … this is version 6 of the design.
I’m pleased with it because the worst deviation from spec is pipe 2, at 1.5mm. Pipes 1,3 and 4 are all within 0.5mm of their proscribed length. Length is defined as the distance the gas has to travel rather than the amount of pipe needed to implement that. As such, all my lengths for the bends are taken from the centre-line radius, rather than the amount of pipe needed to make the bend.
By good luck rather than good judgement, each pipe seems to follow on a theme from the other pipes, and they look like they’re meant sensible runs, rather than all sorts of convoluted bends and wiggles. Furthermore, all the bends are from Alunox stock bends, and I’ve managed to keep to the largest radius for smoothest flow.
It has created a slight issue though, in that the yellow pipe fouls the steering column. I can fix that by slightly changing the route of the column, and maybe adding an extra UJ.