I picked up this book at my local Borders bookstore this weekend. I read through the first chapter and so far it seems like a great book for beginner like me. The only welding experience I had was in shop class in HS. This way I can weld my own pipings if I decide to go turbo.

 

i might have to check that book out it sound cool

and it seems those guys on moster garage can weld just about anything

 

Is that the name of the book?

 

Yep...that's the name of the book.

 

Will have to check that one out. Im fairly good at it now, but you can never get enough info on the best ways or different ways to weld something.

Ive got a few videos and books so far.

Dixit

 

BigDog. I've been doing quite a bit of mig myself. Just little projects to get time under my belt. Question. While welding something like exahust pipe, you can never get them to butt flush all the time. Therefore there are always gaps that have to be spanned. Do you find the push or pull method easier to fill gaps/holes? I keep burning holes even though the settings are at the lowest amperage. I had to resort to on/off and just dab the wire material on there to build it up. But I was fooling around and tried the push method. I laid down a puddle and then pushed the puddle forward. That resulted in a good fill for me. Thoughts?

Oh and Tony, get an auto darkening helmet. Best thing ever.

 

Jeff,

The quick "ZAP" method works to a point but not great cause if you zap the wire inside the pipe, now you got that as a potential problem. In certain cases I will weld closer to the edge of one of the pipes on the gap, then make a second pass on the other edge which will basically close the gap but no risk of feeding the mig wire into the gap. But that takes a bit more pratice because when hitting the edge you easily risk burning a hole or eating it up real quickly.

Also sometimes if you find yourself burning a hole, sometimes its not the amperage you are running being too high, its usually more on the side that you are moving the gun fast enough. Just a thought to think about.

Lately ive turned myself completely away to but welding pipes much because I just doing like the concept of it. There is not too much strength in it. So what I did last on my turbo kit, was slip/sleeved all the joints. But I put the lip on the side where the flow was going. So basically the airflow wouldnt hit the lip, it would "drop" off the lip. Slip/sleeve is so much stronger not to mention easier to weld because its a LAP type weld. Plus as I said, the joint is at least 2x stronger than the standard butt welding of pipes. Plus you dont ever run the risk of shooting the mig into the pipe by trying to weld the joint, thats about the worst thing I think you can do. The slip/sleeve is easy once you get a pipe expander that cost about $20.

On your on/off dab method, thats a pretty good method. Ive used that before, ive fairly mastered that method. Sometimes I actually use that method more even on a straight line weld on a lap weld because ive mastered it to a point where it looks like a roll of coins layed down. Just basicaly do it for looks instead of running a straight line weld. But the zap method of zapping the weld for a split second is very good method for filling a gap without running the risk of shooting into the gap. Its also easier to make it look better than have a BLOB of weld that looks like Hal's "pro-welder" did.

Dixit

 

Haha! My welds are oogly man but there's good penatration from what I can see. There are blue marks on both sides of the metal.

I agree that slip joints are much better. I have a pipe expander but it's not strong enough to make the pipe slip to the next size. Cheapest one I found was like $80. Got a link to the one you use? Slip joints are so much nicer as it's 2x as easy to weld and it's 10x easier to test fit everything before welding.
For straight butt joint stuff, I just push and go. I don't really care if it looks like a tig. I'm having a hard enough time putting down a decent bead 1/2 the time. I think butt welds are strong if you don't grind down the beads to smooth them out. Especially on a mig where the bead lays on top. A good tig won't even need to ground down as you already know.

And yes, I've poked the wire though holes many times. Fortunately, I've been able to reach the wire and knock it off though the closest opening. I also try to lay a bead on either side of the hole but you have to really move the gun fast to avoid making a bigger hole

 

from talking to a friend and watching a few everyday welders, what you do when butt welding pipe is weld a little bit on one side. doesn't have to be real quick but can't stay there for long. basically you're doing a larger spot weld. move to another side and do the same. keep repeating this all around the pipe until its fully welded. takes a while but you don't burn through the pipe at all.

in the end though, i would still agree that doing the slip on method would be the best. any links for some good price, good working expanders?

 

Yeah I try to do that when they are warping concerns. You just make a bunch of 2-3" weld beads until you have it all done. But it's hard to start/end the bead right on the end of an existing weld. So you risk having a pinhole or not that pretty of a weld. Like I said, mine are bad enough already. haha. You can try to move the wire tip in a 1/2 moon motion to spread the weld bead across the butt joint. That helps unlocalize the heat but you have to make sure you get good penatration.

About the only expander I've found was on JC Whitney's site. Just a pipe straightener is only about $20. But a true expander was more like $80. So I hope BigDog can steer me in the right direction. Slip joint can reduce the fab time for welding pipes together probably a 1/3 or even up to a 1/2. Since the slip is usually a at least a few inches long, cutting for the right distance is much easier. Just slip it on and you got some wiggle room either way.

 

Are you guys using gas or just flux core wire?

 

Mig welders put down messy enough beads as it is. With flux core wire, it's worse AND smokey as hell. Considering you have to spend the $ either way. ie... you either pay for gas or expensive flux core wire. You might as well buy the gas and end up with a much nicer weld(as nice as mig can be anyway). I only weld normal steel so I can just use an argon/co2 mix and the appropiate wire. Most exhaust pipe are aluminized steel and most of the stuff my dad and brothers want fixed are just normal steel. But migs can weld ss and aluminum if you use the appropiate wire and gas.

 

whats the lowest amperage setting on your welder.

i weld 18ga exhaust pipe with mine at 110amps and never have a burning through problem but i do try to move quickly


i rented an expander from autozone for i think 30$ and it worked alright and did make the pipe much easier to weld

it looked like this one

http://www.harborfreight.com/cpi/cta...emnumber=37354

the only problem i had was holding the pipe while i expanded it because it wanted to twist on me and i didnt want to clamp the vise down to tight and bend the pipe

 

Actually I don't know. But I only use a 115v low amp unit. 18ga is very thin for exhaust pipe IMHO. 14ga for exahust would be preferred and 16ga or 18ga is okay for intake or charge pipes.

 

use an oil filter wrench...the strap kind or use a strap wrench. don't go crazy twisting it or it'll dent....esp with 18ga.