Threading copper tube?

[jmlcolorado]

So, kinda out of the box, but I'm getting ready to build my own grill for the international rat.
I'm going to be using steel exhaust pipe thats 2 1/2" in diameter.
Using a 'U' to for the two top corners. 2 '45's to form the sides. And 1 90 to form the bottom.
I wanted to use 1/2" steel tubing for the grill portion itself but got to thinking that copper would look pretty cool.
I was planning on welding the steel tubes permenatly in place but obviously can't do that with copper.
SO, does anyone have advice as to how to thread copper?
Im sure it's just like threading steel, only much softer and easier.
Each rod would be cut to length to fit wherever it will be in the grill, then threaded about 3/4" on each side to fasten it from the inside. (all the tube frame will be cut in half once all welded together)

I'll post some drawings of what I'm thinking in a bit to better visualize what I'm thinking.

 

[jmlcolorado]

Here is a couple quick drawings of my thinking:

 

[Rev Tex Devlle]

solder nuts in the end of the tubes, and, drill hole through the frame to attack with bolts

 

[jmlcolorado]

solder nuts in the end of the tubes, and, drill hole through the frame to attack with bolts

Good thought!
That brings to why i asked this in the first place..... can you solder nuts (steel) to copper?

I wanted a clean look by letting the rods pass through the frame, but your idea might be easier.

 

[pistolpete]

It may be possible to thread copper, but usually you would use a thread adapter to get a copper pipe to a threaded end. Copper tube does not have a very thick wall, and therefore could be pretty hard to thread and not have it cut too deep and screw up the pipe. The other issue is thread size/pipe size, as most thread sizes are based on IPS (iron pipe size) and copper is CTS (copper tube size). Like I said it may be possible, but I have never seen it done with any success.

 

[mikes686]

copper to steel?

Im not 100% but i dont think copper and steel can be bonded together. Im thinking like brazing. You need a di-electric union like bronze, my understanding is iron and copper are dissimilar metals. You could however sweat or brazing copper to itself provided you use an appropriate brazing rod with the right flux. Then you coild clean up the joints with a jewelers file the eliminate the excess solder or brazing rod.

 

[billy]

j.b. weld

 

[Rev Tex Devlle]

epoxy the nuts into the tube ? maybe if the fit is right on the leanth of the tube then once the nuts and bolt is tight , it wont come out because the nut will act as a stop will be clean and the bolt head wll be hid behind the grill frame!, funny i was think of how to do this too! guess i answered yours and my question! b ut mad fabber already did this!
!http://www.ratrodsrule.com/forum/showthread.php?t=7279

bout the third pic down on his thread

 

[ruggs]

You can braze copper to mild steel. Try it on a test piece and you will see.

 

[Hydrocarbon Rocket]

I just put a flare on the top end of the tube without a flare nut so it can't fall through the bottom.

 

[Rev Tex Devlle]

I just put a flare on the top end of the tube without a flare nut so it can't fall through the bottom.

yeah thats easy enuff![cl

 

[sneakysnake]

If your gonna solder, use a silver solder and flux. I would recomend using stick copper instead of the roll type it is more rigid.

 

[Torch]

You aint gonna get anything to stick to those nuts if they are plated will need to get them to bare steel before soldering.
you could order copper tube in the right wall thickness to thread or solder in a smaller piece of tubing to thicken the wall

 

[jmlcolorado]

Wow! Quite the responce from you guys on this one [cl
I like the flare idea!, that's stupid easy!
The only thing i dont like would be the rattle youd get from each leg. Though effective, it'll sing like a tin can. But it might sound pretty like wind chimes

i think a 2 part epoxy holding a nut inside the tubing would work good too! Plus even if the epoxy broke, the nut would still hold it in place.
Just have to be careful not to get too much into the threads. Youd have to tap the nuts if you did.

This is getting me pretty excited about this build now

 

[rainman]

I would run run them through and pin them, and let'em float!

 

[Hydrocarbon Rocket]

Epoxy and or solder could give it some ugly green color at ends where applied. Make the bottom hole as tight as possible and the flare will seat in the top hole and probly not seem loose at all.

If you tilt it back just right, It may make a cool whistling chime too! Diferent lengths to tone to your appeal!

 

[mikes686]

oh yeah

You can braze copper to mild steel. Try it on a test piece and you will see.

i'm thinking copper to galvanived steel. anywhos, i know h-d sells braze on threaded ends made from copper. sorry for the misinformation.

 

[ruggs]

i'm thinking copper to galvanived steel. anywhos, i know h-d sells braze on threaded ends made from copper. sorry for the misinformation.

Mike,
Even on galvanised it would braze, just not very pretty and really smelly.
If everyone can wait till the weekend, I will build a mock-up over the weekend. I just happen to have come leftover mandrel bent tube and the copper....ruggs

 

[Sam_Fear]

Wow! Quite the responce from you guys on this one [cl
I like the flare idea!, that's stupid easy!
The only thing i dont like would be the rattle youd get from each leg. Though effective, it'll sing like a tin can. But it might sound pretty like wind chimes

If you built your exhaust right, you'll never hear those rods rattling. Flare the top a a dab of epoxy on both ends or a little brazing, they won't move.

 

[EnglishBob]

Get some 'Redi rod' and either epoxy it in or crimp it in the ends and then use nuts on the ends.I used some copper pipe where the rod actually threaded into it by slightly flaring the pipe and I turned it.