First attempt car body work

[Tobymizzi]

Hi everyone.

Recently bought a classic Subaru Impreza wagon with some rusty wheel arches.

Thought id have a go welding it myself as it's something I've wanted to learn for a while.
I had a bit of practise on a sheet of metal and then decided to go for the real thing.

I'm fairly happy with how it has turned out but wouldn't mind some better informed opinions!!!
Would love some advice on what I could do to make the beads more consistent.

 

[Old boy welder]

Hello, what size is the sheet you welded and size of rods, Did you cut out patch or weld plate over, did you clean off old paint or underseal ??

 

[Tobymizzi]

Hello, what size is the sheet you welded and size of rods, Did you cut out patch or weld plate over

The thickness is 1.5mm. I cut out all the rust cleaned it up with a wire brush and wiped both parts with some white spirit to get all grease off.

 

[qwakers]

White spirit is oil. Don't use that.

 

[Tobymizzi]

White spirit is oil. Don't use that.

Ah fair enough!!!

 

[tom2207]

I welded arches on an Impreza or what ever they were called , they certainly were not 1.5 , closer to 0.8 Id say , very very thin and the rust was not helping.

you wont be running beads on one ,,, so dont beat yourself up over that.

 

[Old boy welder]

The thickness is 1.5mm. I cut out all the rust cleaned it up with a wire brush and wiped both parts with some white spirit to get all grease off.

ok , a long time ago if i did body work and a small rust patch i just cleaned the area with a angle grinder brush and plated over, not sure if that is ok today, rods were thin and low amp, at least your having a go and with practice on scrap metal your get better welds ,

 

[Wozzaaah]

I welded arches on an Impreza or what ever they were called , they certainly were not 1.5 , closer to 0.8 Id say , very very thin and the rust was not helping.

you wont be running beads on one ,,, so dont beat yourself up over that.

I’m pretty sure he means the sheet he used is 1.5mm.

 

[tom2207]

I’m pretty sure he means the sheet he used is 1.5mm.

Ah yes ,, probably , I normally use 1.2 or 1.0 , the Subaru I was at made the steel I was using look like ship plates .

 

[Tobymizzi]

Ah yes ,, probably , I normally use 1.2 or 1.0 , the Subaru I was at made the steel I was using look like ship plates .

Yeah they are super thin! Would it make it easier to use a thinner sheet?

 

[qwakers]

no, the heavier sheet will act as a heatsink. bodywork is typically .8mm, i always use 1.2mm. i never over plate, that doesn't help anyone, it just accelerates any rust. always cut around the patch you've made and butt weld it in, one tack at a time.

 

[tom2207]

Yeah they are super thin! Would it make it easier to use a thinner sheet?

I would be using a bit of 1mm ,,, but ,,, get your self some off cuts and a bench , practice at the bench until you get to the point where you know exactly what will happen when you pull the trigger ,,, only then move onto the car repairs ,, it will save you cutting out what your not happy with ,,, a couple of hours practice will make a huge difference ,,, get some copper to use as a backer too. Ideally someone to show you would be the answer , who knows you may be local to someone who could give you a few tips.

as a side note , is the other side arch as wrinkly too ,, ??

 

[Onthespotwelding]

as a side note , is the other side arch as wrinkly too ,, ??

I’m glad I’m not the only one who noticed

 

[Tobymizzi]

I would be using a bit of 1mm ,,, but ,,, get your self some off cuts and a bench , practice at the bench until you get to the point where you know exactly what will happen when you pull the trigger ,,, only then move onto the car repairs ,, it will save you cutting out what your not happy with ,,, a couple of hours practice will make a huge difference ,,, get some copper to use as a backer too. Ideally someone to show you would be the answer , who knows you may be local to someone who could give you a few tips.

as a side note , is the other side arch as wrinkly too ,, ??

Ok. Noted, will definitely get some more time practicing.
I've seen copper being used, what's the best way to press it on to the other side?

Yes the other side has even more wrinkles. Not too sure how they came about must have been when the metal was formed in the factory. That's my best guess.

 

[Ubique]

I'd say the wrinkles are 'landing creases' from a previous owner that thought they 'know how to rally drive'...

 

[Hotstuff]

First job is always making all surfaces clean. Before cutting any metal away I mostly use a polycarbide disc to remove paint and get back to bare metal on both front & rear of the weld site.

It’s better to remove any paint at this stage to help prevent the parent metal from starting to taper in thickness close to the weld site.

Once you have cut out the unwanted metal, it’s wise to clean the weld site, front & rear, with Acetone to remove all traces of potential weld contaminates.

Welding thin car panels really is an art and it will take you a great deal of practice to master.

Are you using gas-less mig welder?

At a guess, your holding the torch tip too far away from the weld site. You have deposited molten metal onto the weld site rather than welded/fused metal.
You can check if the metals are welded by checking if the welds have fully penetrated.
On such thin metal you will need to make a succession of spot welds around your patch to help manage the heat.
After the patch is secured in place following a first pass, start applying spot welds overlapping the first.
Continue working around the patch at alternate spot welds to help control heat distortion.

It’s not clear if you have butt welded your patch or if it’s a welded on patch.

At a guess the multiple little ad hoc patches are because you blew through the metal? If this is the case, was it because you were trying to weld rusty metal?

YouTube is a good resource for guidance but it’s trigger time that matters.

Good luck and do keep us posted on your progress.

 

[Tobymizzi]

First job is always making all surfaces clean. Before cutting any metal away I mostly use a polycarbide disc to remove paint and get back to bare metal on both front & rear of the weld site.

It’s better to remove any paint at this stage to help prevent the parent metal from starting to taper in thickness close to the weld site.

Once you have cut out the unwanted metal, it’s wise to clean the weld site, front & rear, with Acetone to remove all traces of potential weld contaminates.

Welding thin car panels really is an art and it will take you a great deal of practice to master.

Are you using gas-less mig welder?

At a guess, your holding the torch tip too far away from the weld site. You have deposited molten metal onto the weld site rather than welded/fused metal.
You can check if the metals are welded by checking if the welds have fully penetrated.
On such thin metal you will need to make a succession of spot welds around your patch to help manage the heat.
After the patch is secured in place following a first pass, start applying spot welds overlapping the first.
Continue working around the patch at alternate spot welds to help control heat distortion.

It’s not clear if you have butt welded your patch or if it’s a welded on patch.

At a guess the multiple little ad hoc patches are because you blew through the metal? If this is the case, was it because you were trying to weld rusty metal?

YouTube is a good resource for guidance but it’s trigger time that matters.

Good luck and do keep us posted on your progress.

Thanks for the long reply!

I am using a Clarke 90 pro with a disposable bottle of co2.
There was a bit of wind which probably wasn't helping very much.

I will definitely be looking to get more penetration next time however I wasn't sure if I would end up burning too many holes.
That was a patch however I am definitely going to try and but weld the rest of it as that does a better job.

Yes I did blow a couple of holes but I think the bits you are talking about on the bottom left are where I was trying to weld around the creases so I was trying not to have any large gaps.

I did try to clean it all up best I could. I used white spirit which I have been told that may not be the best thing to use. Also it was difficult to do a proper job of cleaning the other side but I did my best.
The other parts should be a bit easier to prep

I think I am definitely going to get some more practise in before doing another part!
Thanks very much.

 

[qwakers]

If that is a over patch you need to cut it out and start again.

 

[Tobymizzi]

If that is a over patch you need to cut it out and start again.

Ok. Understood

 

[Morrisman]

Don’t try doing runs, just do a row of tacks, hot on hot, one after another. It’s far more controllable and you can see how well you’re penetrating and avoids sudden big holes appearing.