Welding Sunroof Hole - Suggestions

[takai]

True, it would be a large scoop/duct required. Still could be done though.

*see point about roofs not being free.
Trying to comply to regs

[YLD-16L]

Yeah, but technically the roof isnt free.

I C ..............

[M.J.H]

It is on the IPRA car, so there isnt any covering on the bottom anyway, was just going to grind it reasonably flat and then paint it black. One of the best suggestions from PF is as follows:

Which im quite partial to myself. I would just reskin the entire roof, but i was planning to have to do this over the summer, not a week before a state round. Plus its hard enough to find an AE86 which i can cut the roof out of. AJPS apparently has one but i havnt seen th condition of that one yet.

That sounds good but why not glue a couple of strips on the underside then use some metal from an old panel somewhere and glue that on top of the strips, Then just need to fill the gaps and job done.

That sikaflex stuff is pretty strong when set and what is used on the panels on the clubbies.

[rob]

ive found an easy solution

[YelloRolla]

If you can, step the edges of the replacement metal so that it sits in from the underside (snap on make a good swaging punch for this exact purpose) and gives you the best of both overlapping and butt welding (providing a backing and a nice trench for the weld.
Like has been suggested, use 0.6 wire, low amps and short runs (25-30mm long). Have someone with you to cool the welds behind you and work around the rectangle starting one corner, then the diagonally opposed and the same on the adjacent straights. (at least this is how I would do it)

ie (by run #)
1--9--------12--4

5-----------------8

7-----------------6

3--11------10--2

Make sure that you use clean wire, and well prepped metal. Nothing worse than surface rust on the wire for making your job a sow's ear.
Replacement panel should be no more than 0.9mm zinc seal.

HTH and good luck.

edit/ that didn't work well at all! Fixed

[takai]

Yeah, im just about to see what i can do about making an edge setter/joddler/joggler/swaging punch/sheet metal doohickey or whatever its called in each different place. Other than that i was going to go with what you were suggesting except use 0.8mm zinc seal/annealed

[mrshin]

How confident are you with welding stuff? If you're pretty good with a welder, then do it, but if your welding is a bit ordinary, might be best to get someone else to have a go.

[takai]

Heh, ill give anything a go. My welding is somewhere between decent and good at the moment.

[mrshin]

Tried welding car panels before? If not, grab some old guards/bonnets/etc. and do some practice!

[oldcorollas]

Ok, i have to weld up the big hole in my roof this weekend which was left by the silly sunroof. Im planning to pull the seat out and cover the dash and fuel cell with damp towels. I was then going to secure the new panel in with magnets and just tack around it and finally weld it over the course of the Saturday with plenty of cooling time. Thinking of using a generic dolly or chunk of metal to prevent sagging of the welds, but im not sure if it will be needed.

Anyone see anything wrong with that? Or have any suggestions?

cover ALL your glass too. the spatter will melt and stick to glass.. = bad..

and what Yellorolla said.... and maybe you can get away with just bending the edge of the sheet at a shallow angle.. rather than properly stepping, and then skim the gap on top with bog..

[kingmick]

The way i would do it is, get another peice of roof sheet around 30-50mm bigger than the hole. Then go to a sheet metal shop and get them to lower the edge{the thickness of your roof skin, 1mm or so} that you have marked out on the piece of roof sheet against the sunroof bare opening.
Then hire spot welder {can spot weld with a mig if your careful, but proper one is better} or get a panel shop to spot weld it around the lowered edge to the roof.
then on top carefully use fiberglass bog to fill in the deep section of the join but keep it below the roof line so you can wipe it with bog{bog is much easyer to work that fiberglass bog} to get the totally flat roof look The fibreglass bog will hold much better with the flexing of the roof.
Or easy cheap way if dedicated track car would be to get the lip lowered and sikaflex it to the roof with a few 1/8 pop riverts and then bog the top join's.

["Z" UTE]

Takai, some very well made points here. The oversize panel, with the swaged edges is pretty spot on. the top of the insert panel has to flush up with roof skin height.Use a heap of tech screws to secure the panel into place, about 25mm apart. Then weld between every second screw, of course alternating diagonally, side to side etc. Then pull the scews out, and weld that 25mm gap and screw hole. This method will stop the panel from walking, and as long as you keep the job cool, all will be well. Do not build too thick with the weld filler, because all the grinding off, of the xcess weld bead will generate panel warping heat

If it gets a bit like the surf a Glenelg beach, take it to a panel shop, and they will be able to shrink the waves out of it.

cheers Chuck.

[takai]

Im thinking ill probably swage the roof and then place the insert panel ontop. But the same concept. It has been suggested that i keep welding for later and instead sikaflex and rivet this current one into place.

[RT104GT]

Ok, i have to weld up the big hole in my roof this weekend which was left by the silly sunroof. Im planning to pull the seat out and cover the dash and fuel cell with damp towels. I was then going to secure the new panel in with magnets and just tack around it and finally weld it over the course of the Saturday with plenty of cooling time. Thinking of using a generic dolly or chunk of metal to prevent sagging of the welds, but im not sure if it will be needed.

Anyone see anything wrong with that? Or have any suggestions?

Tried to heat shrink a 280ZX roof with a dent and gave up on it.

its very hard work and takes an expert. better try a roof skin

[fade-e]

best option is to change the roof skin as no matter what you do it is going to warp and more than likely warp bad... but in saying this, you can a piece of wood and place it under the area you are welding. what i mean is this...

if the distance from the roof to the floor pan is 1m, then get a 1.002m piece of wood and place it under the area you are about to weld, this will slightly raise the roof a little but giove you a solid base to weld on. therefore, when welding the piece of wood will hold the roof up preventing the warp from occuring

also while welding, have a bucket of water and rag. before you weld, get the rag wet, hold it just next to the weld spot you are about to do. then when you weld, hold rag on the weld immediately so that you get immedaite cooling. this too will reduce the amount of warp.

cheers