Originally Posted by mccmech
To replace the existing drum trap I would do the following:
1) Cleanly cut the copper drain line onto which the drum trap drains.
2) Place a full-band 1 1/2 copper by 1 1/2 plastic fernco band on the drain line you removed the trap from.
3) Replace the entire waste & overflow assembly from your tub ( the drain piece at the bottom & the plate that is on the wall of the tub ). Replace the waste/ overflow with either a PVC or an ABS u-built tub drain assembly. In addition to the u-built kit you will also want to purchase a 1 1/2 sanitary T and a glue P-Trap.
4) Install the new assembly exactly in reverse of how you take the existing apart. By using the u-built you eliminate any compression joints ( all joints are glued except where the plastic goes into the new fernco ). This reduces the chances of a joint failure down the road.
Thank you very much for the write up on this - I am not an expert, but I know enough to be dangerous or I would have not pulled my kitchen apart and I don't have the money to hire someone to do something seemingly simple.
I triple check everything so I should be alright... who the heck puts a ceiling back in without checking