I put on the faucet and tightened down the allen screw etc.. only to find out the "O" ring got nicked and I was getting some drips. Replaced "O" rind and no problems now. My question is I have tightened the Allen Screw about 4 different times getting the faucet on right and not have it secured. How tight can you go with this screw. The bottom of the pipe is chewed up a bit now from the 4 different times I installed the faucet. Can the screw ever go right through the pipe? Or will it kink/flatten it first? Or is the copper pipe strong enough that someone could do this many times?
You'd probably get more responses if we knew what kind of faucet you were installing.
About the only experience I have with tightening set screws onto copper pipes is when installing bathtub slip-on spouts. If at all possible, and you can foresee having to tighten a set screw onto that pipe, then use Type K copper pipe for the section the set screw will clamp onto. I'd be concerned that a set screw could very easily damage the thinner walled Type M copper piping. I don't think it would puncture the pipe, but I could see it crimping the pipe.
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