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cartman13
Aug 30, 2007, 08:48 AM
Hi,

Tried to search, but didn't see an answer:

I removed an old compression fitting from a 1/2" copper tube, and cut the tube using a tube cutter. It was a pretty old tube, so it had some crud on the outside.

I sanded it down with some 100 grain sand paper and then tried to fit it with a new compression fitting. I've tightened it down a bit, and at first look, it would seem fine.

But I've noticed a very slow leak (probably 1 drip ever 20 min. or so) from the compression nut side.

My question is, is this just a matter of cranking the nut down tighter? Or is it possible that sanding with 100 grain sand paper created groves in the copper piple causing a bad seal?

What grain sandpaper is recommened for this? (if this is thought to be the issue?) 150? 200?

TIA

KISS
Aug 30, 2007, 10:06 AM
I'd probably use 400 grit. Here is a link for tighening compression fittings:

Connecting copper - compression joints (http://www.diyfixit.co.uk/nflash/plumbing/CopperComp/CopperComp.htm)

One full turn past finger tight when new.

ballengerb1
Aug 30, 2007, 10:44 AM
That was pretty coarse paper for a copper tube. I'd cut the compression ring off and replace with a new one, sand with very fine emery cloth or 000 steel wool, not 100.

cartman13
Aug 30, 2007, 11:40 AM
Thanks guys!

keebo
Jan 16, 2011, 12:51 PM
I have found through trial and error to tighten hand tight - tightrn with a wrench about a half turn more and turn water on. Then look for leak - if none set a piece of paper around the joint (toilet paper is most sensitive and check it about an hour later. If no leak then it should be O.K. If it has leaked then turn about a quarter turn and repeat the leak test. Do this bit by bit if necessary to avoid a lot of grief later.

copwhistle2
Sep 25, 2012, 04:43 PM
How do you undo a compewssion fitting for a ice maker

massplumber2008
Sep 25, 2012, 05:16 PM
Hi CW2

Shut off the water supply and take two open end wrenches or pliers and firmly hold the body of the valve with one wrench and unscrew the compression nut with the other wrench. That should allow you to unscrew things... reverse to reinstall a new compression fitting.

Mark