In reply to message posted by Wild Bill: What is the proper length to cut the copper pipe coming out of the wall to install a compression stop and euschion?
Normally around 6″ BUT
May I make a very strong suggestion?
Rather then working like the Frauds out there in La La Land why not be a real mechanic and a professional and try the following.
Sweat a copper by female adapter inside the wall like a 1/2 copper female Ell or a 1/2 copper 3/8 Female if it is for a toilet or basin.
Then use a chrome plated Red BRASS nipple ( if exposed) with an escutcheon and then use a threaded by compression angle stop.
By doing the job this way your allowing the next person to come along and replace this valve if needed without resorting to soldering or taking a chance on a leaking compression nut on the supply side of the valve.
A lot of bums that say they are P&H are in reality unemployables and have no clue about disassembling a valve prior to soldering it Or at the least have the consideration of using a heat sink.
By spending a few extra dollars using brass nipples and adapters the next person coming behind you will thank you for caring.
Hey its up to you but I happen to like the best quality and easy or maintenance for the next person to come along even if it is the home owner doing it themselves.