Difficultly threading ABS p-trap

[HalM]

Is it possible that some ABS manufacture's threaded fittings have a slightly different size of thread?
I was repairing a 1 1/2" ABS P-trap with cleanout today. I unscrewed the trap from the portion that goes into the wall and was just going to install a new trap and the fittings that attach to the sink drain. But, the new trap would not screw onto the existing part of the drain pipe. It looked like it would fit but just would not go on.
I ended up using the old trap, cutting and replacing some fittings.
I just don't' know if the issue is because of different fittings from different companies.
Thanks.

 

[Tuttles Revenge]

Threads should be standard. But tolerances could be off.

What portion of an ABS trap threads at the wall. That part seems odd.. or is it a different part that is threaded.

If its a union ptrap then the threads used to mate the J bend to the U bend may be proprietary.

 

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[Plumber69]

Are you screwing the ABS fitting in a metal fitting such as cast iron or galvanized. This will easily cross thread