Welding on header on car, advice?

Bruce.huling · #1 (**permalink**) 05-28-2021, 04:41 PM

I found a crack on header easily accessible. Friend can Tig it. Any advice on preventing damage to car systems? For example, remove battery connections, unplug MSD connector to distributor. Other concerns? Thank you for your help. Oh yes, fire prevention steps will be taken. :-).

cobrakiwi · #2 (**permalink**) 05-28-2021, 05:52 PM

Put the welding ground cable directly on the header tube you will be welding.

eschaider · #3 (**permalink**) 05-29-2021, 10:30 AM

+1^

You will contain the electrical energy to the location of the repair and minimize the potential for damage to in car electronics.

Ed

Jerry Clayton · #4 (**permalink**) 05-30-2021, 07:22 AM

Drill a small hole in the tube at both ends of the crack and then weld--------

patrickt · #5 (**permalink**) 05-30-2021, 09:00 AM

Quote:

Originally Posted by Jerry Clayton

Drill a small hole in the tube at both ends of the crack and then weld--------

Uhhh, but won't all the electricity leak out on to the floor?

eschaider · #6 (**permalink**) 05-30-2021, 07:50 PM

Quote:

Originally Posted by patrickt

Uhhh, but won't all the electricity leak out on to the floor?

It is a risk Patrick but, I think what Jerry is doing with the holes is an old race car chassis builder technique that allows air to escape from a tube being welded that is closed on both ends without damaging the weld joint or the welder.

As the welding process proceeds, the air in the tube is being heated and absent the small air bleed holes the heated and expanding air in the tube would blow out a chunk of molten weld material from the weld joint.

Ed

Gaz64 · #7 (**permalink**) 05-30-2021, 09:45 PM

You drill holes at the ends of the crack before welding the crack up, to remove the end of the crack, so the crack can't continue to crack in service, after the welding is done.
The crack is still evident under the weld if the ends of the crack aren't drilled.

KarlzEE Bebout · #8 (**permalink**) 05-30-2021, 10:18 PM

Holes...sage advice.

eschaider · #9 (**permalink**) 05-31-2021, 01:41 AM

Quote:

Originally Posted by Gaz64

You drill holes at the ends of the crack before welding the crack up, to remove the end of the crack, so the crack can't continue to crack in service, after the welding is done.
The crack is still evident under the weld if the ends of the crack aren't drilled.

You're right Gary. I was solving a problem that did not exist! It is definitely a way to prevent a continued spreading of the crack after welding.

Ed

t walgamuth · #10 (**permalink**) 05-31-2021, 06:10 AM

Quote:

Originally Posted by patrickt

Uhhh, but won't all the electricity leak out on to the floor?

A classic!

Jerry Clayton · #11 (**permalink**) 05-31-2021, 08:12 AM

WOW!!!!!!!!! The method of drilling hole at end of crack came from aircraft repair---not race car chassis repair----and its not just for tubing repair---as I sit here with my morning coffee at 80 years old thinking about all the things I've welded over the years---the worst thing in my memory is cutting some barbeb wire off the top of a fence so I cut weld up the inside panel on a combine out in the field-------and yes-it did catch on fire but there was a creek nearby so the farmer could pour some water on my pants leg until I could get out-----

Bruce.huling · #12 (**permalink**) 05-31-2021, 11:31 AM

Quote:

Originally Posted by Jerry Clayton

WOW!!!!!!!!! The method of drilling hole at end of crack came from aircraft repair---not race car chassis repair----and its not just for tubing repair---as I sit here with my morning coffee at 80 years old thinking about all the things I've welded over the years---the worst thing in my memory is cutting some barbeb wire off the top of a fence so I cut weld up the inside panel on a combine out in the field-------and yes-it did catch on fire but there was a creek nearby so the farmer could pour some water on my pants leg until I could get out-----

You made me chuckle thinking of all the times I set myself on fire welding. Probably my favorite was welding a truss at the top of a 18 foot ladder doing an overhead weld. Darn spark went down my neck and into the top of my pants above the family jewels. Wish there had been phone video back then, I have to think for sure it was comical. I will drill a small termination hole at ends of the crack. I don’t TIG so I’m relying on a local whiz to do the deed. Ceramic coated stainless thin wall I believe. Worth a try. My car is a driver, not a show queen. Chicks dig scars, and I like welds. Go figure.

KarlzEE Bebout · #13 (**permalink**) 05-31-2021, 01:40 PM

A good weld is a thing of beauty, more of an art than a skill.
I took a couple classes at the Mesa Community College when I first retired but since I don't keep in practice, my welds don't look good until I'm about finished. The beginnings are reminiscent of pigeon poop. The grinder is my FRIEND!

cycleguy55 · #14 (**permalink**) 05-31-2021, 03:49 PM

Quote:

Originally Posted by Bruce.huling

You made me chuckle thinking of all the times I set myself on fire welding. Probably my favorite was welding a truss at the top of a 18 foot ladder doing an overhead weld. Darn spark went down my neck and into the top of my pants above the family jewels. Wish there had been phone video back then, I have to think for sure it was comical. I will drill a small termination hole at ends of the crack. I don’t TIG so I’m relying on a local whiz to do the deed. Ceramic coated stainless thin wall I believe. Worth a try. My car is a driver, not a show queen. Chicks dig scars, and I like welds. Go figure.

One of my high school buddies (back in the '70s) was taking a welding class and passed a lit cutting torch at least a foot above his pant leg. The problem was that he was wearing polyester pants without protection and melted them onto his thigh. Ouch.

On another note, a neighbour of mine was a welder by trade, mostly building tank trailers for highway usage. He had no love for welding overhead and said you basically had to let the spatter burn - if you tried to move it you just ended up with multiple burns.

t walgamuth · #15 (**permalink**) 05-31-2021, 08:13 PM

my dad welded at Studebakers back in the late forties early fifties. He said if a drop of molten metal dropped off it would burn through his coverall entering and exiting. You just stood there and waited but if it hit your belt and got stopped by it being too thick to burn through you had to pull your belt and such away from your body so it would pass on down. If it got stuck you got a nasty burn.

Bruce.huling · #16 (**permalink**) 06-01-2021, 09:26 PM

Will disconnect the ignition box from distributor and ground lug from battery. Hope it doesn’t crap something out. Will keep the ground close to the weld zone. Also keep fire extinguisher handy.

KarlzEE Bebout · #17 (**permalink**) 06-01-2021, 10:48 PM

Shouldn't be any flying slag with tig welding also a much smaller heat area.

Jerry Clayton · #18 (**permalink**) 06-02-2021, 07:36 AM

As for the fire exinguisher----------also don't have anything parked outside the garage door---open door so IFFFFFFFFFFFFF you do start a FIREEEEEEEEEE you will be able to roll the car outside and down the drive away from building--------There have been previous occasions of house fires caused from cars being worked on------

indianamoon · #19 (**permalink**) 06-02-2021, 12:14 PM

Ground right on the pipe sounds like the way to go, and weld a bit at a time to keep the heat level down. Love them tigs.

Bruce.huling · #20 (**permalink**) 06-02-2021, 12:17 PM

Quote:

Originally Posted by indianamoon

Cast iron or steel? if cast iron, I always liked to preheat the area to be welded with an oxyacetylene torch, something that you probably shouldn't do with it on the car.....

Ceramic coated steel. Thin wall. Will take off car I decided as I can’t risk hurting something else in the electrics.