Car panel/thin sheet fitting technique

[Shedendman]

hi , yes , you work very close to right angles , as thin cutting discs dont like to be used on their flat , so you are basically holding the disc as if you want to chop through the weld spot , but you dont , and move side to side very very gently about half a mil or as the spot starts to flatten you can drop the angle to about 75 or 80 degrees and gently pull back over the welded area ,,, only do about three or four mm at a time , then off to another location , to prevent heat build up ,,, stick with it ,,, then once the whole weld seam is down flat , i buff over the area with the cutting disc at about 10 degrees and pull back over the whole area , very gently , you get a finish way finer than a flap disc , and lots less metal removal... it is slow , but the results make it well worth the bother ,,, fine body work restoration , not land rover chassis as an example.
hth

Same,but i use a 3mm cutting disc

 

[sjp001]

^. - in case you didn't realise, Paul is a pro. Check out some of the work he has done. Sorry if you realise this.

 

[Shedendman]

restore classic lorrries

Now thats got my interest

 

[daleyd]

So am I.

I also restore classic lorrries as a hobby and the panels are much larger and warp so easily which is why I mentioned it as bodywork is fickle and even professional welders get it wrong with sheet bodywork.

Oooh, can we look forward to seeing some threads and pictures of your handywork? I hope so...

 

[Paul.]

^. - in case you didn't realise, Paul is a pro. Check out some of the work he has done. Sorry if you realise this.

So am I.

I also restore classic lorrries as a hobby and the panels are much larger and warp so easily which is why I mentioned it as bodywork is fickle and even professional welders get it wrong with sheet bodywork.

Just to be clear, I was referring to craig-sm box section not metalmelts panel, long runs on flat panels are asking for trouble with distortion in any position, I've done plenty of such joints, many on stainless with the tig and always use a heat sink where possible, a skip welding technique, and air quenching to quickly remove the heat.

Sorry for any misunderstanding, I should have quoted the post.

 

[Craig-SM]

Just to be clear, I was referring to craig-sm box section not metalmelts panel, long runs on flat panels are asking for trouble with distortion in any position, I've done plenty of such joints, many on stainless with the tig and always use a heat sink where possible, a skip welding technique, and air quenching to quickly remove the heat.

Sorry for any misunderstanding, I should have quoted the post.

View attachment 249231

That was 4 pieces of thin 0.9mm sheet metal bent to right angles then spot welded up. Running a continuous bead on previous attempts just warped it. This was all in my practice before tackling the car, in the pic below. The results were good, the spray painting was abysmal though

 

[Wightsparks]

Just to be clear, I was referring to craig-sm box section not metalmelts panel, long runs on flat panels are asking for trouble with distortion in any position, I've done plenty of such joints, many on stainless with the tig and always use a heat sink where possible, a skip welding technique, and air quenching to quickly remove the heat.

Sorry for any misunderstanding, I should have quoted the post.

I was wondering about a heatsink, I saw a device recently that was a thin-ish copper slipper on a handle to be put behind welds - seems like a good idea if I can create a smooth bit of copper from some pipe or similar.
Ah - a "welding spoon"
https://www.ebay.co.uk/itm/Panel-Be...541433?hash=item3b4d4693b9:g:WQ4AAOSwQjNW~RHL
I'm guessing it's not the answer to all blow through or I'd see them in use more often

 

[Morrisman]

i do a lot of this work , and use the edge of a 1mm cutting disk to level welds , never a flap disc ,,, takes practice , but a lot less heat and a lot more accurate ,,, but it does take practice ,, and patience , the results are worth it though.

I always found a flap disc leaves a slight bulge, when grinding out a weld, unless it is a brand new one, and you go very carefully.

The cut off disc works well, for taking the ‘hump’ off, as it flexes enough to absorb my clumsy fumblings rather than digging grooves and slices.

 

[droopsnoot]

seems like a good idea if I can create a smooth bit of copper from some pipe or similar.

I use an old piece of copper pipe to put behind joins that might need help - for example if I've blown through it and need to fill the gap, or near to a panel edge. Not sure it always makes much difference. Plumber nearby throws out lots of old offcuts of heating pipe, so it's easy to grab a load and make the end into the right shape. Also longer lengths are handy for getting access up behind larger panels.

 

[daleyd]

Covid allowing you can go one better, you can come to Newark next year and see it in the flesh if they can actually set a date, assuming you mean the AEC Militant.

Ah, no pics then? That’s a shame I’m sure a few people here that can’t get to the show would like to see what you have, but never mind eh...

 

[Craig-SM]

Calm down lads, put the handbags away.

 

[daleyd]

Calm down lads, put the handbags away.

Not sure why the anger , I only enquired as it seemed something people on here would like to see. I know I always enjoy the car/truck resto threads, but hey ho.

 

[Wayne.]

Same,but i use a 3mm cutting disc

Do you have a link to the discs you use ?

 

[tom2207]

So am I.

I also restore classic lorrries as a hobby and the panels are much larger and warp so easily which is why I mentioned it as bodywork is fickle and even professional welders get it wrong with sheet bodywork.

yep ,,, i do a fair few of them too ,, 1 series scanias have been the thing of late , at least they are made from decent stuff ,, 1.2 or 1.5 , that gives you a sporting chance but a bit tougher when your beating compound curves .
Oh how i dream of working in alloy , it looks like sheets of craft cheese by comparison to the stuff i get to beat about.

 

[Shedendman]

Do you have a link to the discs you use ?

Any 3mm cutting disc will do,as i dont normally use them for cutting as such(actually,never),just the gentle grinding as stated before

 

[droopsnoot]

Same,but i use a 3mm cutting disc

And me, presuming you mean a 3" cutting disc. I did buy an electric die grinder, but it's not good for that kind of thing as there's no variable speed, and using the edge of a cutting disc to grind welds down needs a gentle touch. I also use the standard 4" one in my angle grinder - varies according to where exactly I'm trying to grind as to what tool will fit. Sometimes I use a reinforced cutting disc in a Dremel-a-like, but only for small areas.