The recommendations for fitting the waste to a Saniflo (or similar) macerator WC suggest that all bends should be 'swept' bends or smooth transitions rather than abrupt 90deg elbows. However, all the 'swept bends' I can find are 92.5 deg, not 90deg. As I have quite a long waste run (around 9m) with minimum fall, and with 6 bends, I want to ensure minimal flow restriction. Is it possible to obtain 90deg 'swept bends', in black solvent weld? Or do I have to resort to using two 45deg elbows with a joining bit to smooth out the corners? Using this alternative solution creates problems with fixing the pipe around external corners because the pipe ends up being further away from one wall or the other and doesn't line up with standard pipe clip spacing.
Thanks for your advice.