as far a the flare for the donut gasket, I bought two 2' lenghts of pipe at a muffler shop and they flared the end of each for free.
Check out these two threads for some tips that will help ... http://www.jalopyjournal.com/forum/...g-and-routing-exhaust-mandrel-u-bends.993838/ http://www.jalopyjournal.com/forum/threads/tech-exhaust-fabrication-tips.435797/
Oh wow. I have to make one of those jigs! I got lucky because my exhaust was kind of simple and I was able to eyeball it and so far it's about perfect. We'll see when I go to lightning everything up! It was recommended that I use a extreme temperature paint for the exhaust pipes and mufflers. This is a fair weather car. Did you guys do that? After going through this process, I think I like it more than the idea of bending which takes diameter in the bends unless someone is blessed with a mandrel bender and I prefer butt welding to expanding first because it's easier and I don't see a down side All in all a satisfying experience assuming it's not going to fall apart in a year
Once you know "how" to look, eyeballing is pretty accurate for many many many things. Almost anything that people look at.
That's a faulty weld characteristic, not one of butt weld's characteristics. It Solely and purely depends on the operator, not the joint.
We build thousands of exhaust systems every year - and just like header tubes that need a weld due to bends being too close together to be able to bend - we Butt Weld everything. we have never has a return for a failed weld joint.
I should have made my comment more clear. Yes, I understand the "credit" for any leaks would go to the guy doing the welds and not the butt joint, itself.
Thanks guys! This is great feedback. I'm very confident in my welding abilities… I just kind a have a knack for it. Now, not pertaining to my Chevy, but to my daily driver which is exposed 4 1/2 to 5 months of road salt per year, would plain old mild steel tubing and u bends with butt welds be ok? There are exhaust parts under that car that are thousands of dollars, and I have re-welded and fixed it so many times… It's close to a full replacement, but if I can save the existing catalytic converter and essentially make everything else, which I have the ability to do, that would be awesome savings but if it won't hold up to the salt then it's not worth it
Ok, sooooo * shitty welders get exhaust leaks. * some shitty welders have better luck with expanded sleeved joint. And there is no inherent problem or downside with butt welds. I didn't think your comment was lacking clarity at all, just wrong
Use stainless pipe and don't coat with anything. Butt welds (with stainless wire and shielding gas) are the right answer, but don't weld the entire system so it can be removed and reinstalled. I did mine in three sections – from the headers to the K member, K member to the mufflers, and from the mufflers back. I used band clamps on the joints so I didn't have to expand the ends.
Easy to make a square cut, it will be the shortest distance across the tube. Open a dial caliper to the diameter of the tube. To mark for a cut in a curve slide the caliper onto the tube, when at the right angle it'll drop over the tube and you mark the start and finsh according to where the jaws touch. remove the caliper and draw a line to connect the 2 points. Again, the shortest distance across the tube is the squarest cut. Anything different and you are slicing lemons.
Unfortunately, stainless wasn't in the budget. Perhaps I'll do that when I have to replace this one someday, which, Lord willing, will not be anytime soon If you meant on my daily driver, that makes sense, again, hoping it's not for a while. Thanks for all this advice! I'm really happy with how it's coming
^^^This is a very weak statement.^^^ Over 30 years doing butt jointed welds on exhaust systems, never had a properly welded joint leak. Some of those systems outlasted the vehicles they were made for.
Yes, my statement may be weak, what you have said in your post is what I was trying to say. A "properly welded joint" is the key to no leaks. That was the thought, behind my initial post.
Stainless is not that expensive. This is the box of pipes I bought for $200: http://www.mandrelbends.com/builder...adius-16-gauge-304-stainless-ultimate-bk.html
on plain steel pipes , VHT high temp paint them , it holds up good once you heat cure it , follow the directions on the can and use the hi temp primer , on my daily I have stainless head pipes and the mufflers and tails are aluminized carbon steel , I cleaned off all the weld joints with a cup brush ( 4" grinder) and primed and painted it and no problems in norther Il 8 years daily driving , put a coat on and then cure it then put another coat on , I used the aluminum color , the muffler and tails look better than the oem stainless pipes .
Several years ago I saw another thread like this. One of the things was mentioned was a piece of tubing about 1/2" long with a raised ridge around it that you slipped both pipes over and welded. They produced what looked like a good butt weld but was much easier to do. I have looked for the last 5 minutes, but haven't been able to find them again. Maybe I just imagined them, as I can't find them now. I thought they were made by one of the major header companies. but it's not Hedman (who is the only one I can think of now). Things like this sometimes comeback to me several hours later, usually waking me up. I'll let you know if that happened.
Don't those go on the outside of the pipe? These go on the inside. I found some exhaust couplers that go on the outside, but I don't think they would look as good as what I was talking about. (Two welds per joint instead of one.)
Shoot I grabbed the extreme temp paint, but not the primer. I'll have to grab that. The $202 isn't bad. Perhaps I'll upgrade in a few years. I think I paid under $100 for mine. Made sense at the time. Good to know that site though, thanks
for me to do but welds on pipe I use a piece of the pipe I am welding cut in half and then lay it on the floor and give it decent wack with a rubber mallet to spread it a little then use 4 worm clams ( 2 per side of the joint ) and use the halfpipe as a support till I get some weld on it so it will support itself then remove it , kind of like half a clamshell clamp
Those two words "properly welded" are the end result to explain when volumes of theory, hours of practice, and years of experience are condensed into a simple term. It's kinda funny when it's used so loosely. You see a fella who knows and understands and possesses what "properly welded" represents would never be able to bring himself to say that buttwelds have a downside or could ever contribute to exhaust leaks. It's ok, I know what you mean and can see where your position is that you're speaking from .
search for current thread here: World's Greatest Welder - then watch you tube video linked in thread: How To Weld On Exhaust Pipe
Hooker made those when I worked for them in the 1990's. Gary Hooker came up with those and they made it really easy to align and weld. I don't know if they still make them after Holley bought them out
I knew it was a header company! A quick look and it seems they don't make 'em anymore. Bummer. Thanks, Holley.
Actually, I was thinking the same thing. How about this : cut a 1 inch section of the same size tubing you are using. Take a hacksaw and cut it along the seam so you can collapse it enough so it can be inserted into the main tube; then weld. That way, you wouldn't need to buy any other tubing, just a foot or two extra of what you are using. Also, you would probably need 1 15/16" OD tube to fit inside a piece of 2 inch. Probably going to be pretty tough to find.
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