I have got myself a little snap on MIG 130 Turbo welder and hoping to tackle the rust in the next few weeks.
Having removed the rear OS window the rust doesn't go back as far as I thought, although I do need to clean it up properly with disc.
However all around the edge has corroded so very thin and brittle. I am not sure what is best to do in this situation. would using a filler to beef up the clean metal be OK / long term solution? Or will I have to cut it all back and fabricate the curvature etc?
By the time you grind all that back, you won't have much left, and you will have lots of pinholes in it. Proper way would be to cut out and weld in new sections.
haha I knew you would say that MM, but one can hope lol
Do you have any advice regarding the curved corners.
I have an understanding of what needs to be done.
Could I ask what order you would do things, and how you would mark up and then cut the corners to fit etc is it just a case of shaping with an angle grinder?
oh come on,,,, its step by bliddy step the way ive posted it..
window aperatures, before cutting gat some thin stiff card and make a template of the corner so you get the shape the same ,or so the theory goes, then cut out the bad back to honest metal , then make a bit to fit, your choice butt is harder so fit behind and tack as others have done , when you have it welded in then use the template you made earlier to mark the shape out and then cut it out with an angle grinder.
mm
metalmick8y wrote:oh come on,,,, its step by bliddy step the way ive posted it..
window aperatures, before cutting gat some thin stiff card and make a template of the corner so you get the shape the same ,or so the theory goes, then cut out the bad back to honest metal , then make a bit to fit, your choice butt is harder so fit behind and tack as others have done , when you have it welded in then use the template you made earlier to mark the shape out and then cut it out with an angle grinder.
mm
Yup just cut out the rusty bits with a 1mm disc on the grinder, make cardboard templates for new bits. I use cereal-box cardboard. Weld in new bits slowly and carefully to keep it as straight as possible. Grind off the welds, maybe give it a light skim of filler to flatten it out.
Heres a similar recent thread....
metalmick8y wrote:oh come on,,,, its step by bliddy step the way ive posted it..
window aperatures, before cutting gat some thin stiff card and make a template of the corner so you get the shape the same ,or so the theory goes, then cut out the bad back to honest metal , then make a bit to fit, your choice butt is harder so fit behind and tack as others have done , when you have it welded in then use the template you made earlier to mark the shape out and then cut it out with an angle grinder.
mm
Thanks a lot MM. I wasn't sure if you generally shape the corner on a bench or with plasma cutter etc.
Can I ask what do you mean by "butt is harder so fit behind"?. Would this not leave a 1mm step around the repair piece?or do you joggle the edge?
Sorry this metal work is new to me and last thing I want to do is balls it up lol
ahh, you will struggle to butt weld it I think so easiest if you fit behind and sand of the welds with a flex pad then a skim of filler. filler is ok for shaping, nothing wrong with it as long as its not being used instead of welding as in covering up holes and the like.
have a prcatice with some scrap .go to your local scrappies or a body shop would be better and blag some of the panals theyve chopped off.
mm
Will the window and rubber still have a good seal with the 1mm distortion? I guess this can be minimised by replacing the metal all the way around even if small bits are OK?
Really appreciate your advice mm thankyou. I have read 2 of your full rebuild threads and complete admiration for your work, even if it does make my tasks more daunting seeing someone with your skill and knowledge attacking them and hoping to replicate
My dilema now is i have poked about and i know the rear arch directly below the leaking window is rusted and i got a screwdriver through on the outer edge of the inside arch. One job at a time. If this debut on the window surrounds goes OK the confidence will spur me to remove arch panel etc and attack it.
ta for the comp's but its only practice,lol
the 1mm well as your say adding the metal from the rear so to speak and filling across the front then the front /outside face will be reasonably flat and true so the deviation in thickness is only about 1mm and this will be at the rear/inside face and should not cause any probs. I asume you are using new rubbers?
mm
Yes new rubbers, however i got a set from JK when i first got the van and knew very little. I have sourced a genuine front screen one but the rear i was hoping to use the jk ones, but not sure if they will fit even though sold as panel van conversion rubbers. Shall see.
Would i fill just around where the 1mm step goes down after the weld or would i try and fill from the step right up to the glass / metal edge?
Can I ask what would be the easiest way to cut the curve for the edges of the window?
I only really have a vice and an angle grinder and some tin snips. I am sure I could get there in the end but was just wondering if anyone knows the easiest way to fabricate them after making a template from card etc
I got the lower corners and straight done. Was a bit of a pain with 2 blow throughs and keeping it all true but got there in the end.
I was wondering if the upper parts defiantly need replacing? They are not rusted as badly as the lower and only pitted slightly and slightly thinner. Could I skim this with a small amount of filler to bulk it back up close to 1mm or is it pointless?
Here are some pics, the upper right one looks fine from inside:
Is it imperative that the entire surround is 1mm for the rubbers to make a watertight seal? Also is slight warping OK (few mm) along the surround? I tried to keep it as true as possible but I still have slight deviation
The problem is that the metal is only a millimetre or so thick, so what appears to be "not too bad" will actually have penetrated through the metal. I would bet if you grit blasted it from both sides, you would have lots of holes. Without a grit blaster, you can't really remove all the rust, so it doesn't reveal the holes.
So what I'm saying is, unless you can grit blast it to bring it back to "good" metal with no pinholes, I'd err on the side of caution and cut it out. If you're using filler over compromised metal (rust removed first obviously), put a skim of fibreglass filler on first, as its waterproof unlike normal body filler.
As for the warping, to reduce it, try to leave your patch pieces very slightly smaller than the hole, so that when the metal expands upon welding, it will have a slight bit of expansion gap. Cool the weld with compressed air if you can. Otherwise you just have to weld incredibly slowly to avoid heat buildup and warping. You may be able to flatten out some of the warping with a hammer and a flat piece of stout metal placed behind.
E D I T: On my van, I got away with replacing the lower window frame and just grit blasting the top.
