dennisbernal91z

iTrader: (2)

I got my vertical door hinge kit, and then need welding to install. I have a mig welder that I use. Can I use my MIG to weld Chromoly to the body?

Or at least a few tack welds, then sometime later take the car to some other place to be fully welded?

Any insight would be great. THX

Angelis83LT

thats a good question.. I wouldn't mind knowing that myself for future refrence

Motor City Mike

Yes. With regular copper coated steel wire, it should weld fine. Even though the drag racing sanctioning bodies (NHRA/IHRA) won't allow it in chassis construction, you can produce a perfectly sound weld, using proper MIG welding techniques. I've got a chromoly driveshaft in my 3500#, mid 9 second car that has a MIG welded yoke - after innumerous wheel standing launches, it still hasn't broken. The welds were not normalized either.

Rob Wade

Yes. Any standard (non flux core) mig wire or tig process will work.

dennisbernal91z

iTrader: (2)

sry if this is a stupid question, but how do you know if your wire that you are using to weld is flux core or not?

Rob Wade

Flux core doesn't required any argon or mig gas. It also leaves a slag covering over the weld that you have to chip off, simliar to stick welding.

Angelis83LT

Ussuallyt the flux core is used on the cheap mig welders from like home depot and such.. the 110v ones... if you have to hook up gas in order to weld, then it is not flux core.

laiky

itis also grey in color or silvery where solid wire is clad in copper. If you snap a piece off you will see the void where the flux is

ede

i've welded CM steel with a gas torch, not the prettiest job but it worked and it lasted.

dennisbernal91z

iTrader: (2)

Oh man. I did buy mine at Home Depot. It does just plug into the wall.

It uses a siler wire. And it has the gas inbeded in the wire, as far as I know. I have done quite a bit of welding with it. Take a look at my website and take a look at the work I have done. I think i can weld these thing....let me know what u think...

Angelis83LT

that is flux core then. it works on some stuff.. but on some things it does not...

dennisbernal91z

iTrader: (2)

Think I can weld to this hinge to my car with the welder I am using. They don't need to be the final welds, but will they be strong enough to get the car togeather and then latter on, once it is back on the road take it down to a shop to have the hinges TIGed in....

I have been welding sheet matal and the roll bars fine so far.

Angelis83LT

sheet metal and roll bars (depending on material but must are mild steel i think) can easily be welded with that little mig.. the thing about chormoly is the makeup of the metal may not let you produce a proper weld with the flux core.. i am just cuessing though.. but best to do it right the first time rather than ruin whatever you are trying to weld

dennisbernal91z

iTrader: (2)

right. Well thanks for the help. I will try to weld a little bit. Just a tack. I will post how it goes.

Just for the record i am welding my lambo door hinges on.

Angelis83LT

ahh yea.. I have a set of those sitting here too.. not sure what i am gona put them on yet lol

83 Crossfire TA

iTrader: (2)

This is a weld that I did using flux core in a little 110V MIG. It’s a heavy cast iron elbow that was welded to a steel flange (the whole ting was welded into a cast iron exhaust manifold for a custom setup). It’s hard (impossible) to tell from this picture but I actually got just enough penetration that you can just see the weld coming through the back side of the heavy casting (not that it makes that big a difference since their was a bead run completely around the inside of the joint to make sure that the thing was sealed).


Chromoly… well, you should be able to get a proper bead and weld with the flux core. You probably couldn’t make an NHRA tech inspector happy with it, but NHRA/IHRA rules are a little weird there anyway. For aircraft stuff, in most cases chromoly tubing is welded using a MIG and mild steel wire (essentially what you’d get with flux core) or a gas torch with a mild steel filler. The problem is that you get a weld that is as strong as the base metal, but you get a margin around the weld of “heat treated” hardened chromoly that self quenched, but it’s not like you’re going to do any better with any other welding process unless you took the whole structure to get it normalized or heat treated after it was done.

dennisbernal91z

iTrader: (2)

Wow thanks for all the help. Last night I kinda went ahead and bit the bullet. I tack welded the hinge on and it seems to be holding. Tonight I will fully weld the hinge one. And also attach the struts to fully hold the door up.

I am pretty much just running the welder as hot as it goes and making a nice thick bead.

I will post pics and how it seems to be going if anyone cares.

Angelis83LT

yes post pics plz lol.. always nice to see pics. Personally i like tig welding.. but i have done alot of aluminum welding... g and most of the weld today make me a little wary about the actual skill of people welding lol.. Some go to fast.. Some in the strait line (vs the small zigzag pattern) and so on.. i have even seen welds that you can brake off with a screwdriver.....

dennisbernal91z

iTrader: (2)

I know I am not a good welder. The welds do not look good or anything but they sure are holding so far. I have to fully weld the hinge on tonight. Then I will post pics.....mind you I am not a pro welder. I am a sophnore engineering student in colledge. I picked up this welder to do some work on my floor pans and never in a million years thought i would be trying to weld chromoly, but here I am. I also can not exactly take the car to a place to have the welding done either.....there is no motor yet or tranny. But I need to doors on to take it someplace so....anyways I will show you how it comes out and I am sure I will get made fun of, but thats OK. Who knows maybe you will say it looks ok.....Either way this is my only means of installing these hinges in my tinny parents' garadge.

Check back tonight...

later

-Dennis

Angelis83LT

lol. that is ok.. I am not a pro welder either.. although i took 2 years as a side course... something to do ya know while i was getting my computer programming degree lol

dennisbernal91z

iTrader: (2)

lol, that seems pretty random in association. But yeah i have just read a manual/book i found on ebay. I just don't want the doors to fall off at a show when they are being held at 90 degrees for a long time. If there seems to be any problems I will most likely just keep welding on more reinforcing plates till the damn thing it as strong as a tank. By then I will be able to take it to a guy that can TIG for me.

Angelis83LT

yep. lol.. I am pretty random lol.. I like my car fabrication... welding.. and computer programming lol.. go figure.. i try not to limit myself lol