Make an improvised guide by screwing together scraps of 2×4. Saw using a handsaw with a blade that’s 3 or 4 inches wide. Note: Square pipe ends fit snugly into the fittings, allowing plenty of contact ...

It's possible to join ABS to PVC, but it's only supposed to be done with a mechanical coupling, not glued. If you just came here for the answer, you can stop reading... but I think you want the whole ...