Copper Exhaust???

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2door

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Copper will work just fine but you'll need to know how to use silver solder instead of the soft, 50/50 stuff plumbers use for water lines. You might get away with 95/5 but even then the vibrations might shake it loose.

Silver solder requires a flux and some practice. There is another product used in the air conditioning trade generically called Sil-Fos, which is a silver solder containing phosphorus that cleans as it melts and is used in high temperature applications on copper and doesn't need a flux. Sil-Fos is expensive so be prepared to spend some $.

Practice and get proficient before expecting the joints to hold. The copper can take the heat with no problem but the solder joints will be the challenge unless you have experience with proper soldering technique.

Tom
 

mew905

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can I just use JB weld? and what do u mean you need flux? like a flux welder? If so, I'm in luck, my roommate picked one up dirt cheap from his pawn shop
 

BoDean_LP

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I JB welded a pipe once. It worked great! . . . for that day. The next time I fired it up, the JB just cracked and vibrated off while I was out riding.

I ended up pulling into a car repair shop where one of the mechanics welded it up for free. I tried to tip him, but it was "against company policy" or something like that. Too many other guys around to slip it to him. Of course, it wouldn't be so easy with a copper pipe. You'd have to pull into an HVAC shop or something, and I don't think they'd volunteer to do it free.
 

biknut

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Copper to steel is very difficult to weld. Like Tom said, silver solder is about your best, and only bet, but it's not easy to do unless you're very experienced at it.

What I used was silicone tubing I got from Sick Bike Parts, and hose clamps.
 

2door

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JB Weld? Ha Ha Ha Ha Ha . You're joking, right?

Flux, as in a paste that you need to apply to the copper before soldering. It cleans the area and allows the solder to flow better. You'll also need to sand the area where the solder joint will be. Any surface oxidation, dirt, grease or other impurities will not allow the solder to flow or adhere to the copper.
It is not the same as flux core wire used in wire feed welders. That is for steel. A totally different animal. If you've never worked with copper you need to do some research and practice before you can expect your joints to hold and keep the exhaust system from falling apart.

Tom
 

MEASURE TWICE

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I had used screw together copper pipe that adapter made connection to the size thread on Briggs engine / muffler.

The replacement gasket from the rubber part was to be fiber high temp washer, but they did not last. I am making copper gasket to seal now.

Can't say it is the cheapest, but does not require welding and although I have a mig welder it does nice weld, but not on very thin metal. Even with setting available not a chance, til maybe I get an oxy acetylene set up and can silver solder.

http://motorbicycling.com/showthread.php?t=29678&page=6
 

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2door

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I had used screw together copper pipe that adapter made connection to the size thread on Briggs engine / muffler.

The replacement gasket from the rubber part was to be fiber high temp washer, but they did not last. I am making copper gasket to seal now.

Can't say it is the cheapest, but does not require welding and although I have a mig welder it does nice weld, but not on very thin metal. Even with setting available not a chance, til maybe I get an oxy acetylene set up and can silver solder.

http://motorbicycling.com/showthread.php?t=29678&page=6
Let us know how your MIG welder works on copper. I'm very interested.

Tom
 

mew905

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I may be able to get someone to do it for me, but I lost all the silicone tubing (went for a ride, vibrations "removed" all the copper, so I had to buy new stuff). I just wasnt sure how to permanently affix the copper piping. if steel would be easier to work with, I'll see if I can find some of that. Might be pricier but the silver look would look better on my bike too.
 

MEASURE TWICE

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I had not checked on welding copper with my MIG as it came with a little spool of flux core and solid that are both for steel. I have AR CO2 tank, so only yet tried solid true MIG for steel.

I checked on cost for stainless but it was very expensive. Aluminum it suppose to do also, but have not bought the wire for that either. I have a life time supply at the rate I weld of the solid 030 size and got the optional big spool adapter. I have done not much smaller than 1/8 and up to 1/4 inch very nice on steel. It run on 120 volts with a 20 amp outlet regular plug Hobart AutoArc 130.

MT


PS

Also to mention my copper flex exhaust uses no welding at all and it does turn a near black color after it has been used first 10 minutes. Stainless you can use too, I've seen it done. It was just I needed a shorter length and it was sold in the stores in 3 foot shortest length. No way to adjust it since working with all parts from plumbing supply store and removing and making replacement gaskets that can withstand the heat. Also be sure if you do this too, that some of these pipes also have a plastic sleeve that I show in my thread how I removed it as it would melt and burn too. No replacement is need for that part as it is not a gasket. It is only there to prevent galvanic action in water pipe systems preventing active corrosion.
 
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dracothered

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Can copper hold up to the job of being an exhaust system? If it can how would one go about putting it together?

As you can see in my picture my exhaust port comes out the side of my engine so I need to do a sharp bend to be able to route the exhaust. This is some of the reason I asked about copper as I don't know if I could bend EMT conduit that much.
 

MEASURE TWICE

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I would think there is a flange to thread adapter that you could then get a thread elbow 90 degree and go from there. You have to check if parts fit together and also fit on the frame too.

MT
 

MEASURE TWICE

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I have aluminum cast carb 90 degree angle bend adapter on my engine to clear the seat post tube. It is a flange fitting, just don't know how well it is rated for temperature. Something like that already made is something I'd look for.

MT
 

mew905

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I read somewhere a 90 degree turn could hurt power (gases dont like sharp turns), though if you're just looking to get it running, then it's fine. But yeah, I think one to three solid pieces of steel would hold up alot better than copper would, plus I could bend it, then weld it into one solid piece. If I knew where to get sheet metal in my area I'd build my own exhaust like jag's.
 

biknut

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I read somewhere a 90 degree turn could hurt power (gases dont like sharp turns), though if you're just looking to get it running, then it's fine. But yeah, I think one to three solid pieces of steel would hold up alot better than copper would, plus I could bend it, then weld it into one solid piece. If I knew where to get sheet metal in my area I'd build my own exhaust like jag's.
How about a muffler shop for steel tubing?

Some people use electral conduit.
 

mew905

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really? I thought conduit was only plastic? I asked minute muffler here but they dont have pipe that small (what is it? 1 inch OD?)
 

2door

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Ace Hardware and others sell pre-bent EMT. It comes in 90 and 45 degree short sections. Usually the bends are sharper than you can get using a conduit bender. Shop around, Home Depot, Tractor Supply or an electrical supply house should also carry it.

EMT welds nicely with TIG but it takes a little practice and skill due to its thin wall.
Some very nice exhaust systems have been made by members here using conduit and with a little work it can be polished to look like chrome or painted.

Tom