Best way to weld a cracked frame

Well, recently I found a crack in my 400's frame, so now I have to take it and have it welded. I know very little about welding, so I thought I'd ask you guys which method should be used to weld it. So which would be the best way to weld it, Mig or Tig? Of course it is the stock round tube steel frame.

Most of the cracked frames that I've heard of have been at the front shock mounts or rear shock mount, but mine cracked in a different place. I would post a pic but I don't have a digital camera, so I'll try to describe where the crack is at. I don't know what you would really call it, but it is the cross tube that the rear shock linkage mounts to and that runs between the main frame tubes at the bottom rear of the frame slightly behind the footpegs. The crack is on the left side (shift lever side) where the cross tube connects to the main tube. The crack is barely even noticeable, but is about half-way around the tube. The crack is right along the edge of the weld where the cross tube meets the main tube and looks as if the weld is simply pulling away from the main tube.

I really didn't think I was being that hard on it riding it in the woods. Sure, I ride it hard, but it isn't jumped very much and even when it is, it isn't over 3 or 4 feet (can't do much more than that in tight woods without tagging a tree), and it has never been wrecked. Oh well, maybe I was riding it harder than I thought cause I also bent the axle riding in the woods.

I would greatly appreciate any advice on how I should have my frame welded. Hopefully I can have it welded and it will hold. If it doesn't hold, then I guess I'll be saving up and calling Lonestar.

[OutlawEX]

well most of the time u dont have a choice because the metal on frames are different than what alot of welders can weld ong...Like most of he time mine is tig ,or wire welded,but put a plate over the cracked area and weld the plat to it to reenforce it,dont just weld a bead which alot of ppl tdo,its pointless it will crack again if you do

the 400 frame can be welded and gusseted with a mig welder.

[Scott]

Tig is used for welding aluminum.
Mig is a wire feed welding. Mig is just an easier version of "stick" welding, and will work on everything up to really thick steel (like a bulldozer).

Like blindsided said, MIG weld your 400 frame. Grind out the crack (to make room for the "new" metal from the weld) and clean it up, don't just buzz over the existing weld. But any welder worth a crap will know how to weld it up for you when you take it to them.

[Pappy]

sorry boys....tig welding is merely a type of welding...mild steel...aluminum..chromoly all can be tig welded. you may need to switch to different gas and etc.

[Scott]

Thanks for the clarification. I had only seen aluminum tigged.

[Pappy]

hahaha.....i tig rollbars in race cars all the time...it is a much cleaner weld i think.....but i still love the sound of my mig throwin sparks!!!

Originally posted by 400ex127
hahaha.....i tig rollbars in race cars all the time...it is a much cleaner weld i think.....but i still love the sound of my mig throwin sparks!!!

good news then,,,bring that stuff with ya to hatfield so we can weld up the 416 before its powercoated...:D :D

[Castor-426ex]

yeah tig welding is awesome..you actually can control the amount of amperage ya know current.... while you weld...its all cool...im ok at most welding processes...im trying to master thermal arc and plasma cutting
and actually mig welding is not meant for thick steel...i wouldnt think of mig welding anything over 3/4 of an inch and expecting it to hold up...especially if its going to be under stress..
mig welding is more or less a bodyshop mans Tool...hehe

Kenny my dad is tryin to sell a water cooled tig...
I think its a miller...and it may be multi processed...its sweet...but im not sure what he wants for it...Ill get pics

you can mig or tig it there is not much difference in quality. I would tig it though, Tigging does not get the metal quit as hot and therefore does not weeken it as much as mig welding. The weld itself are basicly the same strength but the heat from a mig or stick will weaken the metal around that area very slightly.

[TheX1992]

i also found a crack in my frame, right in front of my left foot peg on the bottom frame. all the way through, i could see light through it. quick bead on wire feed works pretty good. i would have like to used angle iron on it but it was pretty cramped (right below countersprocket and foot peg) but its holding up so far :)