Push fit joints for plastic waste pipes
These are the simplest of all types to use but are generally that much more expensive.
A full range of fittings is available. These have a rubber seal retained inside, which is squeezed between pipe and fitting to form a watertight seal.
Measure and mark the length of pipe, making an allowance for the part to be inserted into the fitting. However, once the pipe has been pushed fully home, it should be withdrawn a little (1/4 inch or so) to allow for expansion.
Cutting plastic waste pipe
The pipe should be cut to length using a small hacksaw and a piece of straight edged paper wrapped around it to act as a guide for square cutting. Clean off any burr with a small file so that the end is smooth. This is particularly important with the inner edge, since the waste water flowing through may well contain debris which will quickly build up to form a blockage around any rough surface.
Apply lubricant to the pipe so that it does not push the sealing ring of the fitting out of position.
If none is supplied, a little washing up liquid does a pretty good job.
Assemble the joint by pushing the pipe home and, as noted before, withdrawing it a little to allow for thermal expansion.