Lucky teaches himself to weld! And hasn't burnt himself yet!

[lucky]

As I posted somewhere else here recently, my exhaust manifolds are cracked again. I was just gonna say fuck it and order headers from wcf a little earlier than I planned (car is very loud, and my neighbor, the cop, has been giving me dirty looks). But it turns out the wife's car needs new front brakes (again), and of course she doesn't have the $$ right now, so headers will have to wait. And as usual, several of my friends offered their welding expertise, but when the time came to do the job, they were all no where to be found, and not answering their phones.
I did some reading this last week about flame temps, angles, proper prep, anything I could find that seemed like it was from a reputable source.
Took a while to think about how I wanted to approach it. Decided to grind off as much of the old weld as I could, use a round high speed cutter to kinda create a depression along the edges of the cracks (kinda like cutting a v in a cracked fiberglass panel before filling it), and drill 1/16" holes at the ends of the cracks to try to eliminate the stress points where the crack might continue to run.
The oxy/mapp micro torch I bought when I was gonna try to braze shut the TB cooling lines on my t-stat housing had a small but informative brochure that assured me it could produce a hot enough flame to weld with. The procedure for adjustment it described to get to that flame was a little off, but I eventually got the hang of it. Unfortunately, I burned through 3/4 of the only oxy cylinder I had figuring it out, but with what remained I filled one of the stress holes, and about 1/3 of the crack on one manifold. Gonna get more gas tomorrow, and see if I can finish it up.
Took pics as I went, my host is no longer accepting new pics, will see about posting them after I get home from work tonight.

[Aaron]

That's odd. I know how to weld, and still got 2 3rd degree burns building my headers :scratch:

[Fastback86]

Tell me you're kidding. I took welding classes for a year while I was in junior college, used 3 different kinds of welders and never burned myself once. Were you trying to burn yourself?

[whipped]

I got some nasty arc burn when I first started using the TIG...

always wear long sleeves and sunblock!

I never got the hang of torch welding. Always looked like crap and I ended up wasting $8 worth of oxygen and not getting anywhere. Stupid oxygen. All around me and so damn expensive. worse than bottled water.

[lucky]

The hadn't burnt myself, yet, was a reference to everyone calling me "Lucky." I burnt myself twice at work tonight. I never said it looked good, I just said I figured out how to adjust the flame and 'successfully' plugged a 1/16" hole and filled 1/3 of the crack I wanted to fill before I ran out of gas.
I'm gonna try to see if I can get a decent signal and upload some pics, stupid neighbors should buy a better wireless router... hehe.
edited for spelling

[Aaron]

Tell me you're kidding. I took welding classes for a year while I was in junior college, used 3 different kinds of welders and never burned myself once. Were you trying to burn yourself?

I am too impatient to understand that shit gets hot after welding, and needs lots of time to cool. So to see if it had cooled off enough yet, I grabbed it. It hadn't. Same story for the second burn.

[lucky]

Wow, I at least spit on it before I tried to grab anything. I used regular work gloves today, I destroyed the welding gloves I had cleaning the charbroiler at work. Still no luck on a decent signal...

[Fastback86]

Tell me you're kidding. I took welding classes for a year while I was in junior college, used 3 different kinds of welders and never burned myself once. Were you trying to burn yourself?

I am too impatient to understand that shit gets hot after welding, and needs lots of time to cool. So to see if it had cooled off enough yet, I grabbed it. It hadn't. Same story for the second burn.

Wow, I don't think they call that impatient...and twice? Really? You've got a learning curve like a torque curve.

[lucky]

Well, I said pics, here they are:
Baby's First Torch

Crappy weld that my landlord TIG'd on there for me

After grinding off the old weld


1/16" hole at the end of the crack in an effort to eliminate the stress point

First day didn't go so hot, this ones after I ground off some of the excess weld I put on.

Day 2 was a thing of beauty, call it beginner's luck or whatever, but this weld is purty. Too bad this is the bottom side and all anyone will ever see is the ugly shit on top.

Stuff I found lying around in my great grandfather's abandoned workshop
71 vega model kit from the 70's
Antique Scotch Electrical Tape Tin
Safety goggles from the 50's
Antique Stant radiator cap
Full can of Dexron II dated 1967

Got the manifold back on, just in time for work. Spent about 12 hours over 3 days messing around with the torch, grinding old and excess weld off the pipe, and taking it off and putting it back on. 3 cans of oxygen, 1 can of MAPP, and 3 welding rods later, car's been driven in traffic for a 1/2 hour, it's quieter (front manifold still makin noise, maybe my next day off I'll try to do somethin about that), and it's holding at the moment. I'll see how long it lasts.

Didn't burn myself. Had a close call with my foot; wore proper shoes for all but the last 10 minutes of workin with the torch. Saw something that didn't look right, tested in the dark with a flashlight and saw a pinhole I missed; went to try to fill it and a glob of weld hit the floor 2 inches from my big toe. So what did I do for an encore? I went right to work after putting it together where I smashed a stack of plates, nearly broke my finger and had to throw away a bunch of food that had shards of porcelin in it. My boss is pissed.

[Blue Shift]

See, the problem here is that it's gonna be hard to get a good enough flame for long enough to get it done just right. There couldn't be much oxygen in those low pressure type cylinders. Propane/Ox torches also burn cooler than Oxy-Acetyline, though it'll be hot enough. Also the TIG weld on there looks like shit - too cold, but it looks like you did a better job!

Anyways, all that aside, make sure to wirebrush/sand the shit out of the area - contamination will play all sorts of hell on you. Light it up, go for a neutral flame (Torch flame adjustment: http://www.tpub.com/content/aviation/14 ... 18_645.htm) Wave the flame over the area to be welded and preheat it good, though for thin wall tubing, you may want to be careful in getting it too hot, since you can burn through it easily enough. So focus the flame and produce a puddle, then swiftly dip the end of the filler rod (should be stainless, but any steel will do I guess) in the puddle. The idea is to move the puddle and constantly keep dipping and melting off the end of the rod into the slowly moving puddle so you're leaving an even trail of cooling metal puddle behind.

On thinwall tubing, especially welding 2 sides of a crack, it's not so easy, you'll have to move the torch in, get it hot, dip filler and get the torch and rod out briefly to give it time to solidify, then move back in, heat and dip, and pull back again to cool. You don't have an amperage pedal like TIG, but you can control heat by moving the flame closer or further, or angling it, etc. The trick is to balance getting the base metal fully melted and the filler rod melted in, but letting it cool periodically so the puddle doesn't finally drop out and leave a hole!

[Standard]

I looooove torch welding. Haven't had a chance to do it for quite some time, though. I remember playing around with the oxy torch in tech school and welding some 16 or 18 gauge steel that was laying around. I think I like doing it more than mig or stick welding, but haven't had a chance to tig yet.

How was that setup to use while welding? I've got the same thing but have really only used it to torch bolts and such. I think I've got a crack in the exhaust manifold of my Cherokee and I'd like to get under there and weld it up instead of spending $200 on a new one..

[Billybo455]

doesn't look like he tigged that. looks like a reall cool mig'd deal. either way. the guy didn't know what he was doing.

tigs are the best things going. short of me needing to weld something over 1/2" i weld everything with a tig because it's pretty!

[lucky]

The pamphlet said about 20 minutes of burn time per oxy cyl at welding temp. Was a wicked PITA because both days it was windy, as you can see from my first pic the workspace I have isn't really flame friendly, so I had to work in the open end of my garage and the wind was a bitch.
Torch performed well, actually did burn through the tube once.
Just thought about it though when BlueShift said stainless filler; didn't even read about what filler I should be using. Silly me just used the flux coated bronze that came with the torch. Guess it's not gonna last long (oh well, if it fails again I can just try to do a neater job). So I shoulda used stainless filler? There a specific flux I should be using?
EDIT: Oh ya. Puddling. I really wanted to grind some of the globs of fill outta the inside of the pipe, but I had to get to work. I'll take care of it next time I have the manifold off; maybe I'll even post pics of my genius setup for eliminating 90% of the flying debris from exhaust manifold porting. :thumbup:

[The Dark Side of Will]

Silly me just used the flux coated bronze that came with the torch.

Don't look now, but it's brazed, not welded... :scratch: :thumbleft:

[CincinnatiFiero]

Thats a cool little pocket welder setup. I prefer to mig weld, mainly becuase its the first one I was taught. You can rent real welders for like $40 at tool rental places. That will lay a stronger weld.

[lucky]

Don't look now, but it's brazed, not welded...

Figured as much. So it won't last at exhaust temp after all. Oh well. It's still quieter than it was, even if it is only a temporary fix.

[The Dark Side of Will]

Don't look now, but it's brazed, not welded...

Figured as much. So it won't last at exhaust temp after all. Oh well. It's still quieter than it was, even if it is only a temporary fix.

I don't know about that... keep your manifolds from glowing and you'll be ok for a while.

[lucky]

The filler's already starting to discolor.

[The Dark Side of Will]

Heat does that. Even titanium changes color in exhaust applications.

[lucky]

The crappy looking fill on the top of the manifold is already failing.
C'est la vie.