compression fittings cutting the tubing

Zuma · 10 Dec 2012 at 12:30

Hi,
Currently working on my first watercooling setup and my fittings arrived today.
they are alphacool 16/10 compression fittings from a competitor

anyway i have tried them out because it'smy first time with compression fittings. i find that if i tighten them enough to hold the tube in place they cut into the tube quite a lot. if i only do them medium finger tight then i can pull them out fairly easily, which kind of makes a mockery of using compression fittings in the first place.
overall i am dissapointed with the design of these fittings, but i want to know from more experienced users what i should be expecting with compression fittings in general.

the compression ring has a sharp 90 degree flange on it, and i was expecting a chamfered profile to it. sorry can't do pics at work, so explanation might be lacking

cheers for any advice

Cleeecooo · 10 Dec 2012 at 13:17

What size of tubing you using snail?

Zuma · 10 Dec 2012 at 13:27

16/10 tubing. the correct size for the fittings.

Cleeecooo · 10 Dec 2012 at 13:50

Hmm, that's odd

Is the tubing actually being cut, or is it just being squeezed and a deep indentation being left?

kiel367 · 10 Dec 2012 at 13:55

try warming the ends up over a boiling kettle to soften them up then try and put them on?

Zuma · 10 Dec 2012 at 14:05

it's not an indentation, it's cutting partway into it and gouging a chunk out of it.
i can tighten them less, and it won't cut into the tubing but then i can pull the tubing out if i bend it a bit. just leaves me with no confidence in these fittings compared to what i read about compression fittings in general.

i've read that they can cut into the tube a little bit but this just seems excessive.

Cleeecooo · 10 Dec 2012 at 14:53

Are you certain the tubing OD's match?

Is this happening with all the compressions?>

Zuma · 10 Dec 2012 at 15:03

yeah it's defo the right tubing, it was boxed up and labelled 16/10 and the fittings re 16/10 too
ive only tried one fitting, because i was thinking of returning them. might try another, but i reckon it will be the same. this fitting doesn't seem defective, it's looks like thats just how it is.

will try and get pics later

Andy__C · 10 Dec 2012 at 16:03

kiel367 said:
try warming the ends up over a boiling kettle to soften them up then try and put them on?

This worked for me when I was sure that my compression fittings and tubing were the wrong size.

Its still bloody close, however 12 months on and no leaks.

blky · 11 Dec 2012 at 03:14

Andy__C said:
This worked for me when I was sure that my compression fittings and tubing were the wrong size.

Its still bloody close, however 12 months on and no leaks.

i can also testify to this method, although on some of my tubing i did slightly shave down some of the o/d to get the compression fitting to fit as well.

been just over a year and no leaks here

Zuma · 11 Dec 2012 at 16:18

well i decided to send the fittings back. not just because if the bad fitting. i actually got them to fit kind of ok in the end (still not brilliant) but mainly cos they sent some of the wrong size so i couldn't have finished my build with them anyway. and 24 hours after sending my original complaint they didn't reply so i just rma'd the whole lot (this is not ocuk, its another supplier)

i think i will go with barbs now, cheaper and easier to tell if they are on ok.