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brianpgriset
04-07-2006, 05:50 PM
Anyone have any tips or tricks as how to bend soft copper tube in as tight a radius as possible without crimping it? I am replacing the copper airlines on my compressor as the old ones are in pretty rough shape.

Mike W
04-07-2006, 05:54 PM
You might try filling it with sand and plugging the ends so it stays put.

jniolon
04-07-2006, 06:07 PM
what size ??? how tight ??? There are some good tubing benders on the market that work like exhaust benders and form the tube without crimping...... the cheap way is pack with wet sand like Mike said, but I don't know how small a radius you can turn... depends on wall thickness and i.d. of tube...

Imperial Eastman makes good 'lever benders'... Rigid makes a good bender for copper work... google tube benders and you'll get your fill...If you're bending soft copper, you can probably bend it by hand around a coffee can or smaller... just take your time... steel tubing isn't quite as easy...

john

brianpgriset
04-07-2006, 06:14 PM
No steel tubing, I know you need proper tooling for that. Im just trying to do some 1/4" and 3/8" OD. For the 1/4", around a 3/4" radius would be desirable. For the 3/8", I would like to get a 2" or so radius. I tried both by hand and was not able to acheive these radiuses.

Broccoli1
04-07-2006, 06:14 PM
You can also pick up a Spring Bender- about 8-10 bux

http://www.ridgid.com/Tools/Spring-Tube-Benders/index.htm

Push the Tubing through the Spring and bend by hand

Pangea
04-07-2006, 06:58 PM
Small copper tubing bends and coils for an air compressor. Riiiiight!;) I used to have an 'air compressor' with copper bends and coils on it. The BATFE paid me a visit because of the liquids that it was discharging.;)

Broccoli1
04-07-2006, 07:04 PM
Small copper tubing bends and coils for an air compressor. Riiiiight!;) I used to have an 'air compressor' with copper bends and coils on it. The BATFE paid me a visit because of the liquids that it was discharging.;)

:D :D :D :D

EvanK
04-07-2006, 09:56 PM
Imp makes a good tubing bender tool.

DaveD
04-07-2006, 11:40 PM
For that small of a tubing check out your local auto parts store.

tailshaft56
04-08-2006, 02:02 AM
Small copper tubing bends and coils for an air compressor. Riiiiight!;) I used to have an 'air compressor' with copper bends and coils on it. The BATFE paid me a visit because of the liquids that it was discharging.;)


TORPEDO JUICE!! UMMM GO:p :p :p OD

Y2K
04-08-2006, 09:41 PM
I've had some success filling short runs of tubing with lead, and melting it out after bending.

If nothing else, it's an excuse to fire up the smelter, and cast a few .451 *****.

toolaholic
04-08-2006, 11:02 PM
I do all the trades. I have a tube bender for bending soft chrome tubing for toilet feeds. i believe it has 3 or 4 bending shoe sizes in a row

tailshaft56
04-09-2006, 12:29 AM
They make an alloy that melts at low temp. I have seen it in the Enco catalog but i don't remember the name. It's meant for stuff just like this. When I put in my HF auto drain I just used soft copper tube and bent it around a HF bender die.

Masher Mfg
04-09-2006, 09:39 AM
Do you have to have a tight radius? I've seen a 270* coil loop rather than a 90* on many setups. This also gives the system some flex reducing cracking problems. Only consideration here is if the loop starts to vibrate to can crack. Sometimes a rubber lined clamp is need to stop vibration.

Garauld
04-10-2006, 12:36 PM
As tailshaft mentioned, the stuff is called Cerro alloy and can be bought from McMaster Carr and probably others. They have different melting temps, but you can get some that melts in hot water. It's expensive - about $30/# but for what you are doing, a little should go a long way. I wonder how much of it will adhere to the inside surface of your copper since it has a lead and tin composition...