I am in the process of patching up some rusted out holes in the floor of my truck along the upper rocker where it joins the main floor and rebuilding the attatching flange for door seal and the channel area behind that that joins up to the floor. In the open areas all seems to go pretty well by hammering and dolly work after tack welding, let it cool repeat etc.. No cracks.. the tight area adjacent to the top of the rockers and up to and behind the rubber seal lip are giving me troubles with a crack on one side or the other of a 4 sided patch. I can't get underneath the patch on top of the channel or the rocker for hammer/dolly work to remove some stresses. I have however had some success with an air hammer.

What can someone advice as a procedure to reweld a straight line crack of say 1- 1 1/2 inches long??? I reweld and sure as all get out they will crack as they cool!!!!

I am an amateur at this so please forgive stupidity if possible.:)

Try not to get the weld any hotter than required. You did not say what you were welding with or where you were doing it at and what the air temperature was. The weld is cooling too fast and shrinking to much causing the crack.

Mike

Weld from where the crack ends back to where it started. What are you welding with? mig? gas?

Gas weld, outside the garage, about 30 degrees ( on a good day!) Probably about the worst condition for welding I guess. Is the hammer and stress rellieving part of the answer.??? Would it be better to post heat???

The 30* is not helping at all. Post heating will help. Material is simply being shock cooled and shrinking to much. Try heating the garage up as well.

Mike

The truck is outside.

AAAAASRRRRRRRRRRRGGGGGGGGGGhhhhhhhhhhhhh!!!!!!!!!!!!!!!!@(^&^**$$%^& CRASH !#@%#@^#^%$&& CLUNkkkkkkkkkkk!!!!!!!!!!! ^%*^#$*^*(&*(()*+)__()*(& !!!!!!!!!!!! SPLANG %%$*(()__)** WHAT THE>>>>>>>>>>>!!!!?????? Oh NO~!!!

OUCH!!!!!!! blated cracKKKKKKKKKKKKKKKKKKKKKK!!!!!!!

Thatys whqat it sounded like out there tonight. The closer I get to calling this side of the truck floor done the worse it gets. Ity seems as the integrity of the floor is getting stronger ,,, now the cracks are popping up in new places!!!!!!!!!!!!!!!!!

What THe ????????? Where did I put that BErrrrrrrrrrrr BEER BEER BEER BEER BEER!!!!!!!!!!!!!!!!!!!!!



only had a few dear! Get me another wil ya

Thinking about finishing patching the holes and comiong back after all pieces are in and welded and all the dang cracjsss are done and brasszzing in the dawrnm things shutemnn!!!!!!!!!!!!!!!!!!!!!!


Can ya see my point here ??????????????????????????????????

Brazing's what I mean!!!!!!!!

Sometimes you have to admit defeat and go to sleep. Tommorrow is a new day :)

:but: :no: Wherth the BEEEEEEEEEEERRRRRRRR dear run toi the stiore and getaa sixx pack please????????????????????????:whine:


AAAAAAAAAAAAAAGGGGGGGGGGGGHHHHHHHHHHHHHH!!!!!!!!!!!!!!!!@#$^@^@$^@&@$@$%#@&@&$@%$^


















Alright ! I'll try it again with a new approach tommorow.








;)

any better today? Or should I start to buy stock in wire?

Sorry, can't help it . LOL @ pebbleboy.

:b69: SSSPPLLANKRCKKAAAAAAAAACCCCKKKKKKKK@%#%@^%%^@##^




Same thing different night different techniques same resultss..

I tried welding just small spots of the crack by preheating either side a few inches back and just welding a 1/2 inch or so of an 1 1/2 crack and then as soon as I finished the weld I covered it tightly with a 4 way fold of cardboard and held it there firmly for several minutes until .................................................................................................... ........................................................................................








SPLOICRNCKACKSKLINGACK another crack in the same place!!!!!!


Picture this: I have the entire run of the lower door seal area patched and welds are fine along the lineal length of the run of the area adjacent to the seal raised lip. I have 4 sections of this run spliced together so there are welds that run 90* to the length of the lower door seal section .. This is where the biggest crack issues are.
I believe that there are stresses that I can't seem to overcome when I weld these cracks shut and they cool and pull apart.
Is there a stress relief technique that I should apply here BEFORE the weld ? Or after , during etc...............

help:whine:

Anyone?? I still need the help here if possible.
Thank you

Seriously.....................................anyone at all????????????????

Dude, forget the brazing and get yourself a real welder, or pay somebody to weld it up after you get everything aligned.

I'm with 72cstc5, I've never had a mig weld crack (that I'm aware of...)

Good luck and don't give up! Rg

ttt

Well I have stumbled onto the solution! Somewhere on this board I found a link to a list of FAQs and one was on welding sheet metal and very informative: The weld tack or bead, as it cools, shrinks at the weld and the adjoining area immediately around the weld. the trick to relieve the stresses is to smack it with ahammer and a dolly behind the weld to stretch it back and relieve the stress. Do it as the weld is applied and still hot. This is why you see old time body guys with a stand for the torch so they don't have to fumble around ;and relight after every tack.

By the way, the Victor welder that I am using is a 'real" welder. a torch weld has better penetration than MIG and leaves a flatter weld. Right you are , I could pay for some one to MIG it for me but I prefer to gas weld it since you can't pay enough for someone to do that . Most welding salesman selling the small MIGS look at me like I have a 3rd eye when they give me the sales pitch and then I tell them that's okay, I use a torch!!!
I've used MIG a lot through the years and it is far easier and a lot faster I will agree, and that's why it is so popular. Anyone can strike an arc and run a bead that looks like a submerged arc after they get good at it .
I have been told by many a seasoned welders that the prefered
methods are gas and stick for strength.

Not trying to cause any issues with the good advices and chuckles that I got on this subject, just pasiing along some more info for the next folk who might stumble onto this topic.:metal:

Glad to see you got it worked out. :metal:
persistance pays off :)