help straighten out door patch panel, please

I want to learn the right way to do this and I know theres guys here that can help. (Same old story , I never post much but Im always following along).
I finally started working on my '51 cranbrook again and its time for patch panels. I figured going slow and keeping the panels from getting warm that they wouldnt warp, Wrong!
This is the door bottom on the drivers side and you can see the 2 panels came together at different angles. I clamped them then used a dolley from the back side to push the two pcs flush (checked every spot w/ a straight edge before spot welding it). I think forcing the alignment is where I went wrong, but now what do I do?


Here you can seethe two planes comping together at different angles.


What makes it tough is I cant swing a hammer inside the door frame to hammer the backside of the weld outward (which is what I think needs to be done).


Ive shrunk metal before by heating a small spot then quenching w/a wet rag, would this do any good if I did it along the weld line?

Thanks in advance for any advice.

Jeff

 

Somebody help this guy out, so I can go fix both doors on my tub!

 

i say you shrank the metal along the weld seam allready, holding the dolly on the seam from inside the door and hammering on the weld will stretch the weld area, and some off dolly hammering above and bellow the weld seam will push the weld back out, thats how i would go about it, wait for others to respond there may be a better way.

 

I looks like it is already shrunk and needs to be stretched. also if you used a mig welder it has a harder weld than a tig and if you hammer and dollie to much on the mig weld it can cause the weld to crack

 

What I'd like to know is how you hemmed the edge over on the bottom and sides when you were done welding the long weld. I've never seen anyone patch the bottom of a door like that.

But I suppose if it worked, it worked. A porta-power in the back side and some tapping above and below the "ditch" should push that out, it's not that bad really. You could try a stud gun with a slide hammer too (or good ol' screws and a slide hammer) but I find that only works on thinner late-model stuff.

 

Can you fit a dolly inside the door? If so, you need to stretch the metal on both sides of the weld line. You can stretch by hitting the outside panel, if the dolly can fit in there. I'd start at the center and work both ways, checking with the straight edge. Maybe leave it a bit low until you get the hang of it....then go back and bring it all the way.

It looks like maybe you ran long welds? That will shrink the heck out of tin.

Also overheating with a grinder will shrink it a bit.

 

Yes I can get a dolly inside the door.

No long welds, They were all spot welds untill they all connected, then slowley ground it to make sure things didnt get warm.

Thats why Im wondering if things really didnt shrink too much, could it be its just because I forced the 2 pcs into alignment then they bowed back when I let go.

jeff

 

they don't bow back really, the weld side surface shrinks more then the opposite causing the pull in effect.

 

Looks like you did a good job with the fitting. The heat from welding is gonna warp any panel.
Start hitting it from the inside first with the dolly or a hammer. After you get it a bit closer you can start hammering on dolly with a lot of pressure on the dolly. that will help you raise the really low areas. First finish welding the rest of the skin.

 

The pic with the straight edge really looks like the valley was caused by shrinkage. Yes, I know what you mean about forcing the panels to fit, but I don't think that caused it.


Trying to stetch with the dolly inside will take some time and practice. Try an area of your choice and keep checking with the straight edge to see if it is working. Don't go all the way out until the whole entire seam is brought back out evenly...then try to get the last of it stretched out.

Going too much here, and not enough there, will likely get some oil canning to appear, so go easy.

 

Thanks for heading me in the right direction guys.
I headed to the shop tonight to see what I could do. Although Its not as close as Id like, I can live w/ it (heck, I knew it would need a skim coat anyways). Ill still try a little more when I take the door back off.




I had to weld one of my dollies to a pry bar to reach and pry/push a little, I still think if I could hammer from the back side this would have been a pc of cake.


jeff

 

Did you start with any crown in the panel, or was it flat?

 

Don't mean to hi-jack.Good thread!
I used the mig.After grinding down the welds.I started to go at it with the hammer and dollie on the quarter panels of my Chevy. The weld started to crack when i was working the metal.Now I have to re-weld. What should i do to prevent it from happening again?

 

Probably not MIG welding it. MIG welds are hard, so when you starting working the metal there is a good possibility that it will crack.

 

the panel was pretty flat when i started, but the door bottom originally looked flat also.

jeff

 

I like your dolly set up, sometimes just getting inside those door panels is the hardest part. it looks like you were able to get a good bit of the area stretched back up. I have had good luck working out the skin after all the tacks are done and working the panel out as you weld.

 

Why dont you just cut the part of the inner door skin that stops you from gettin the dolly in the back and then re weld it when youre done? Sounds silly i know, but on hoods and trunklids with big stamped inner skins sometimes its the only way to work on the back of the outer skin.
Good work still, i im a newbie at sheetmetal too and i encounter this kinda problem almost everyday. I guess its all good. A few years from now its goin to be us replying w/ good advice to guys askin for help.....at least i hope so.

 

I got that part already
Brazing,Tig,anyone? anyone?Bueller?anyone?

 

looks like you are going to use bondo to smooth it out, i have seen car shows use it on new panels and customs all the time

 

Tig is a softer weld . Also gas welding is soft but easy to over heat the metal I like and use Tig myself . I would never braze a panel as over time nothing sticks to br*** (paint, plastic filler, ect.)

 

The body filler was the next step I was gonna get into. Then the freaking welds started to give.
I only have a mig available, so i'm going to give it another try.This time I've hammered and dollied the patch panels to where it looks good before I weld.

 

It is still going to shrink when you weld it there is really no way to avoid it. Here is a link to a article by Randy Ferguson on Mig welding sheet metal that might help.

http://fergusoncoachbuilding.blogspot.com/

 

Its a long shot, but having the same issue myself and not being experienced enuff w/ tig nad not having a O/A set up, next time i'll try workin w/ the ahmmer b4 grinding. Its goin to take more time no doubt, but im positive it could solve the problem.
Im gettin a O/A set up as soon as i can afford it anyway.

 

Thats a great article K13. I have seen those shrinking disks before too.
I guess I'm heading to Harbor Freight(no arm twisting there)to get me a full body hammer kit.
I've been working literally with a hammer and a beat up old dollie.

 

That will need a little filler but thats no sin.All welds shrink you just have to stretch them out with a little hammer on dolly work.