Welding a sunroof hole closed

[Mr_B]

My M3 has a sunroof and this is bad. During a bare shell restoration, is it going to be wise to have a panel welded in so that you can't see it. New roof skins are unavailable.

[dickkark]

I bought an ex police cossie sapphire a few years back and did it the other way round,putting in a sunroof.

Just bought a roof with pillars from a salvage yard and drilled out the spot welds where the main roof joins the side panels/pillars which was covered by trims anyway making it much easier to hide.

I believe the bmw is the same layout.

If you weld a piece in,the roof would probably buckle and warp with heat as its mostly unsupported large spans which would leave you needing a lot of dressing and filling to finish,
bearing in mind the roof will have a double curvature also meaning finding another roof skin without
sunroof to cut a bit from or shaping a new flat sheet of steel,which is not as easy as it sounds!!
HTH

[dilbert]

I agree that this isn't the easiest thing.
Equally how hard could it be?

I know nothing about this, but I'd say it was doable, if you can get a steel sliding panel for the roof. If the roof only ever had a glass insert, you might be scuppered, although it might work if you can get a partial roof (the important bit).

Don't electric weld it.... Solder it (and use gas welding if you have to).

Welding is what you do on the structural bits. Soldering is what you do on the bits you want to look nice.

Edited by dilbert on Tuesday 26th February 02:29

[alsaautomotive]

New non-sunroof roof panels are available for the M3's, & if it's a bare shell rebuild anyway then it's actually not a difficult job to replace the roof - we've recently done one on a 320 Production Championship/show car.






(The 1st pic is as we collected it & NOT our workshop btw!!!!!!!!!!!!!!)

[Mr_B]

Thanks all. I 'll have to re-check this again with the dealer - I was told the roof panel is NLA from BMW. Nice work on that race car,Al.