Filling a beetle sunroof hole

[keithski122]

Thought I would post this job I'm doing on my baja bug.
I bought this bug from austrailia but don't like the sunroof which leaks.After a lot of thought about different ways of doing this I decided on stepping the hole and spot welding a patch panel in.The new panel was cut from a scrap beetle.Unfortunately when the sunroof was removed the roof flexs a bit so I've held it up with some wood which will hopefully hold the shape while its welded.I was thinking of using a shrinker/stretcher to shrink the rear edge a little to tighten it up a little, whats everyones thought on this?
Anyway photo time:-

 

[Coo]

Looks like you have a great pre-weld fit for the panel.

 

[pedrobedro]

Stick it in with Sikaflex and just paint the Clecos

 

[candygt]

Looks like a great job so far! As Coo said the panel looks to be a tight fit so I would expect nice results!!

 

[Coo]

At the risk of repeating something you probably already know.....

Take your time welding around the edge, keeping heat build up to an absolute minimum..
That'll help reduce any warping

 

[keithski122]

Thanks for the positive input.
As I said I'm spot welding it so hopefully distortion will be minimised anyway.I'm going to lead load the outer seam to blend it better then I will have to give it a thin skim of filler or glaze.The inner seam I'm going to seam seal with wurth bond and seal.
My main concern is how the roof sags slightly with the wood removed, I'm hoping when its welded it will be ok.

 

[Windy Miller]

Nice looking job so far Keith!

What are those 6 'things' placed around the edge of the infill panel? Saw some the other day on another forum holding the rear wheel arch on an MGB before it was welded.

 

[pedrobedro]

What are those 6 'things' placed around the edge of the infill panel? Saw some the other day on another forum holding the rear wheel arch on an MGB before it was welded.

Those are the Clecos I mentioned in my post Google Cleco fasteners

 

[the snooper]

cant really tell but from the picture it looks as though you will be overlapping the joint ie the new panel sat on top.
if i were you i would cut it exact and put a strip behind the joint so that its flush when welded in less filling to do and you wont see the repair

 

[bigbadbugga]

Nice looking job so far Keith!

What are those 6 'things' placed around the edge of the infill panel? Saw some the other day on another forum holding the rear wheel arch on an MGB before it was welded.

http://www.frost.co.uk/item_Detail.asp?productID=8352

 

[keithski122]

I am overlapping it but I've used a rolastep (ratchet flanging tool) to create a step in the roof so the repair section sits in this and becomes flush.You can just see this in one of the photos.
You're right they are clekos, I don't use them usually as normally I would always butt weld any repair section as I don't want to create rust traps.I don't think this is a rust trap area though and it will be well sealed.I'm not butt welding this as it is bound to cause huge distortion if I mig it.

 

[the snooper]

ahh i see never noticed you had stepped it
have you thought of adding some bracing to cut out some of the flex you wanted rid off

 

[Windy Miller]

Ah ha! Now I know - thanks Guys!

 

[Angusdog]

ahh i see never noticed you had stepped it
have you thought of adding some bracing to cut out some of the flex you wanted rid off

I think it will be fine in terms of stiffness with an overlapped join. Once welded, the double thickness of german steel (as opposed to thin modern car panels) will aid greatly.

I saw how Rolls Royce MIG the aluminium roof on the Phantom - two weldors do exactly the same metre long weld on either side of the roof in one hit, which gives them no distortion. Just find a weldor identical to you to weld one side while you do the other

Seriously, if you follow the guide on here (welding in very short blasts) I doubt you'd get much distortion.

 

[pedrobedro]

ahh i see never noticed you had stepped it
have you thought of adding some bracing to cut out some of the flex you wanted rid off

Do the bracing like they do on the buses, cut some wood to the roof profile and stick it in place with Sikaflex or Tiger Seal PU adhesive.

 

[Dr pepper]

You can get an attachment for a spotter to seam weld, sort of a pair of rollers with a sliding contact, I dont think that machine of yours will have the power though, they soak up a lot of juice.
They were using them in a exhaust plant I worked at to do the seam around audi catalysts boxes.

 

[keithski122]

Nothing like a bit of work on new years day!
Did the spotwelding today and I'm pleased with the results for a first attempt.Quite a few messy spots, a few blow throughs, all caused by lack of experience with pressure and timing plus the welding arms flex a bit due to their length.It should be strong enough though and a lot less distortion than mig welding it.Need to clean it a bit then lead the seam, then a skim of filler.The photos show the distortion though its not as bad as it looks, about 1/8 inch.The best thing about it though is when I removed the supporting wood the roof held its shape fine.

 

[keithski122]

Got another hour or so in today so I tapped up the low spots and had a go at lead loading.Didn't make the seam invisable but that wasn't the intention, just to seal it a little.Not sure what to do paint wise as I painted it a couple of years ago but not really happy with the results, got a small problem with micro blistering.I've decided that bare metaling then epoxy primer is the way to go, just haven't really got the time or space to do it all in one go so may do it a bit at a time.

 

[Wriggler]

You've made a decent job of that

 

[split999]

You've made a decent job of that

Totally agree.

well done.