Spot welding body panels

[CasKru]

I've got this slight problem with my driver door on my van. Some of the spot welding has cracked on the front part of the door where it hinges. This has the effect that when you open the door it slightly drops down as the panels got pulled apart slightly.

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Now what I want to know is will I damage the paint if I spot weld it again (invertor welder).

My plan is to take off the door and put it somewhere on a work bench. Then take a bucket of water, fill it with ice and dip a towel or cloth in it. Then I'll take the towel and put it on the underside of the spot I want to weld and drape it all around the spot I want to tag weld. Will this keep the metal cold enough to not damage the paint work on the outside of the door?

Alternatively, what else can I do if this won't work?

[Oupa Stig]

Cassie, it's a bit tricky to figure out the exact setup - is there a cavity between the area you want to weld and the outside "visible" side of the door, and thus your concern is more heat conduction? Then your koue lappie trick might work, but if the surface you want to weld on is directly on the inside surface of the outer "visible" side you WILL damage the outside paint. Remember, welding requires molten metal, even thin rod low amps... Bleeding heat off to avoid conduction over short stretches should be easy enough with you ice, etc, and if you arc for really short moments, and cool the welded area immediately after each arc - maybe...
Would brazing not be more successful? (I don't know brazing, but have been the proud owner of a brazed-together opel kadet) . Is it not a cooler process RE the surrounding material, as the brazing rod get heated, not the surface which is to be brazed - so a lot less heat conduction...???

[Froll]

Any form of welding or brazing will damage the paint even with a wet cloth. Would sikaflex not maybe do a better job?

[Mud Dog]

Brazing is a big No-No. It requires a lot of heat the material (cherry red heat) before the brazing rod can be brought into the mix. Heating the material is slow by comparison to MAW, TIG, MIG or CO2 which allows too much to be lost in conduction to try save the paint. It will also cause the sheet metal to warp / deform

I think your best bet (DIY) would be to use the MAW inverter that you have and pack the whole weld area with wet clay as a heat sink, leaving just the weld spot exposed. Quick touch downs with the torch with slightly raised amperage would fuse the metal instantly with less heat transferred to the adjacent material. Do some practise runs on similar thickness sheet metal to get the amps and technique right.


You're still going to have a small 'burnt' area after but you can clean it up, treat with rust converter and paint it using a pencil brush.

[ThysdJ]

Cassie I am on standby with new stickers.. Jy gaan hom brand pappie...

[Oupa Stig]

Dankie Oom Andy, - I thought brazing might be a cooler process, never having tried to do it myself before... Which is why I asked, and thank goodness you answered!

[wim]

Cassie luister na Andy hy is spot on.

[Haboob]

Sikaflex would do a better job

[CasKru]

Thanks for the advise guys. One of the questions was if the metal I was going to weld is the sheet on the outside of the door. It's not.

Think of it like this. you have two sheets of metal lying on top of each other. The bottom sheet sticks out 5mm out from the top layer. Now if you should take that overlap and fold it back on itself, trapping the edge of the sheet on top, that is more or less the setup. The outer door panel is the "bottom" sheet and the inner panel with the door hinges etc is the "top" panel.

The idea is basically to try and dissipate the heat. I will basically make arc for half a second because it is really thin metal. I first though of using sicaflex as well but those sheets are so close together that I doubt if I would be able to force the sicaflex in there. alternatively I supposed I could take the inner door panel off and try and force the sicaflex in from inside that cavity

[CasKru]

Maybe just too get a better picture... my problem area is the seam indicated by line A in this picture (this is just a picture of the web and not my car door). DO you think I would be able to force in the proper amount of sicaflex to do the job in between the sheets (remember they are flush at that point)... using B in this picture?

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[louis fourie]

Cassie, ek dink nie jy gaan die sika in geforseer kry nie. Dit gaan net verdere pogings om te sweis vermoeilik. As jy die deur my kan kry, kan ons probeer om hom te TIG weld. Ek sal voorstel om die deur op 'n pap nat handoek neer te sit, maar kan nie waarborg dat die verf gaan verkleur nie. Ek glo nie 'n mens het lang welds nodig nie, net genoeg.

Sent from my GT-I9300 using Tapatalk 4 Beta

[Thabogrobler]

Ek dink nie Sikaflex gaan die ding doen nie - Sikaflex laat beweging toe en jy probeer juis beweging stop?

[JEEPIE]

Any form of welding or brazing will damage the paint even with a wet cloth. Would sikaflex not maybe do a better job?

+1

[Ali3n]

Any form of welding or brazing will damage the paint even with a wet cloth. Would sikaflex not maybe do a better job?

+1

Ek dink nie Sikaflex gaan die ding doen nie - Sikaflex laat beweging toe en jy probeer juis beweging stop?

+1

Eish Jeepie, You are contradicting yourself here. You agree to the first statement of sugesting Sikaflex and then agree to Sikaflex possibly not working.

[Family_Dog]

He is confused - that's why he bought a Jeep...


-F_D

[blom]

cas
hou die buitekant koud met nat handoek
dan maak jy koud onmiddelik na die weld (water)
weld met erg dun rods kyk of jy dunner as 2.5 kry laer amps minner hitte kinda gedagte

[CasKru]

cas
hou die buitekant koud met nat handoek
dan maak jy koud onmiddelik na die weld (water)
weld met erg dun rods kyk of jy dunner as 2.5 kry laer amps minner hitte kinda gedagte

Thanks Blom

Het ook intussen gedink... wat as ek die earth los hou van die werk af, dan die rod teen die punt druk waar ek wil weld en dan net die earth so vinnig teen die raam raak en dan weer weg vat sodat die rod kan vasbrand. Dan kan ek die rod af breek en net gelyk skuur. Sal dit werk?

[Mars]

Ek glo nie daardie laaste een gaan werk nie. Die boog ("arc") is nodig om die filler in die rod te smelt en te deponeer op die oppervlakte wat ky wil vas heg. Ek dink nie daar gaan genoeg metaal neergesit word om 'n sweis las te maak wat gaan hou nie. Ek dink jy moet jouself afvra wat die beste opsie is tussen die deur behoorlik regmaak met die wete dat jy hom maar sal moet laat oor verf of sit met 'n deur wat weer lostrek en in elk geval dan behoorlik gedoen gaan moet word. Miskien is jy dan tog gelukkig en kry die ding gesweis sonder om die verf te beskadig. Die een voordeel wat jy het is dat jy darem nie direk op die buitenste paneel sweis nie maar op die gedeelte waar hy omgerol is. Jy sal dalk regkry om die buitenste paneel koud genoeg te hou. Ek sou gaan vir die aanbod om te TIG. 'n Man wat sy storie ken met 'n TIG Sweismasjien kan wondere verrig.

[CasKru]

Thanks Marnus.. Sorry vir die dom vraag maar is TIG welding maar net nog 'n vorm van "arc" welding waar jy 'n positiewe en negatiewe het nie?

[Mars]

Ja dit is maar jy kan die stroom baie presies beheer en dus die minimum hitte gebruik om die panele te sweis. Veral daardie wat so dun is.

[CasKru]

Ja dit is maar jy kan die stroom baie presies beheer en dus die minimum hitte gebruik om die panele te sweis. Veral daardie wat so dun is.

Gaaf dankie man.....

dink ek moet vir my so eksperimentele "deur" opmaak en toets. Seker die enigste manier wat mens met die meeste sekerheid sal kan se

Dankie vir almal se insette

[vanthev8man]

gaan haal n beskadigde deur by n s/h spares winkel en "oefen" eers daarop.

[blom]

nee man weld die deur
as die ferf dan nie lekke is nie plak daai "bullet hole" stickers op die sotwelds
sieda niemand sal weetie

[CasKru]

nee man weld die deur
as die ferf dan nie lekke is nie plak daai "bullet hole" stickers op die sotwelds
sieda niemand sal weetie