Welding the sunroof

[TexasTerp]

My goal this winter is to begin turning my e30 into a track car/winter beater. First up on my list is to weld my sunroof shut because the tabs are rusted and it leaks like crazy.

For those who have welded theirs, did you remove the headliner completely? Did you remove the cassette framework? If so did you experience any issues with the roof flexing or warping?


I'm eventually going to put a cage in it, which will add reinforcement, but that's after I put in a fuel cell (rusty gas tank right now).

[AndrewBird]

I think a lot of race car guys just silicone it in place as looks aren't important. If you weld, you will have to take it slow as not to warp things. I would gut as much as you can.

[series88]

P.O of my track project seems to just have used bondo. And did an ugly job cosmetically but it works. Im trying to re do it.

[10Toes]

I removed the whole cassette and used 3M panel bond 8115, Welded 4 tabs to hold it while the panel bond cured.

If you are not planing on repainting your car then mask the roof and around the area to glue and pull off the tape before it cures. Also put tape on the bottom edge as a backer so it does not all drip through.

[dirtbag30]

P.O of my track project seems to just have used bondo. And did an ugly job cosmetically but it works. Im trying to re do it.

same here. p.o seemed like a cool guy and did everything else good to the car, but used bondo to seal the sunroof shut. looks like crap and the roof is probably ten pounds heavier now. but its sealed and doesnt leak.

[TobyB]

Most of us pull the cassette- lets you get the cage tighter, also removes weight.

Don't remove the rear roof crossmember, though- it looks like the cassette, but it supports
the rear lip of the roof, which will sag if you do.

Then you make a number of spacers- I think I used about 8- and set them a bit below
the surface of the roof. They need to be 1/2 the total gap, and then they'll wedge
the sunroof in place to make installation a LOT easier.

Weld them to the roof with tack welds and water on top, and
the paint will survive. Then weld the sunroof panel in place the same way- use a tack
on each one at first, as you can contour the sunroof to the roof, and it'll look a hell
of a lot better. Otherwise, the roof goes wonky, and it looks pretty crappy.

When everything cools off, your favorite 'high build- for large body gaps'
seam sealer works great- put tape under the gap inside the car to keep it from falling out,
lay a big bead in the gap, let it shrink, repeat 2 or 3 times, and your sunroof is removed
and the hole sealed. You can paint the sealer if you like. Do paint the welds underneath.

I suspect if you wanted, and had a right angle drill, you could use bolts or rivets to
do this job, but it'd be fussy.

hth
t

[Ray Smoodiver]

TobyB is bang on, but I can't stress GO SLOW enough.

[kendogg]

I haven't done this on an E30, but on an E36 you can simply remove the sheetmetal cover from the sunroof cassett, and bolt in a couple pieces of aluminum bar to hold it in place. Bolt the bar to the cover, bolt the whole thing in place. You'd probably be adding the same weight as if you mig welded it.


That, or just buy one of the fiberglass inserts and use adhesive to install it.

[capn]

Subscribing, would love pics if there isn't a DIY thread already.

[Fusion]

Use magnets to get it held nicely in place, then tack.

[TexasTerp]

Thanks for all the great advice! I'm definitely gonna look into a couple of these methods!

Most of us pull the cassette- lets you get the cage tighter, also removes weight.

Don't remove the rear roof crossmember, though- it looks like the cassette, but it supports
the rear lip of the roof, which will sag if you do.

Then you make a number of spacers- I think I used about 8- and set them a bit below
the surface of the roof. They need to be 1/2 the total gap, and then they'll wedge
the sunroof in place to make installation a LOT easier.

Weld them to the roof with tack welds and water on top, and
the paint will survive. Then weld the sunroof panel in place the same way- use a tack
on each one at first, as you can contour the sunroof to the roof, and it'll look a hell
of a lot better. Otherwise, the roof goes wonky, and it looks pretty crappy.

When everything cools off, your favorite 'high build- for large body gaps'
seam sealer works great- put tape under the gap inside the car to keep it from falling out,
lay a big bead in the gap, let it shrink, repeat 2 or 3 times, and your sunroof is removed
and the hole sealed. You can paint the sealer if you like. Do paint the welds underneath.

I suspect if you wanted, and had a right angle drill, you could use bolts or rivets to
do this job, but it'd be fussy.

hth
t

This is awesome advice. thanks! I'm probably going to be using new sheet metal, instead of the current panel, so I'll be cutting it a lot tighter, but the basic process seems like it should be the same.

Subscribing, would love pics if there isn't a DIY thread already.

I'll probably start a build thread once a good bit of the bodywork and fuel cell install is done. I'm traveling a lot over the next 3 months so it'll be slow.

Lots to do though, gotta repair some rust in the floor boards then rhino-lining the floor. Gonna swap in a fuel cell at some point too, I can barely drive the car with how bad the rust in the tank is right now.

[10Toes]

Pics of my delete. It's for a race car so I didn't bother to make it perfect, just panel bond and a little filler.

[F34R]

I think a lot of race car guys just silicone it in place as looks aren't important. If you weld, you will have to take it slow as not to warp things. I would gut as much as you can.

^this, my Dad was hurrying and warped mine badly. I am planning to cut it out as a gallon of filler is dumb.