BGT side window rear corner metalwork

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Not_Anumber
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Joined: Tue Sep 22, 2020 9:33 am
Forename: Chris
Surname: S
Location: UK

BGT side window rear corner metalwork

Post by Not_Anumber »

Has anyone here had expereince of doing small bodywork repairs in the rear corners of the side windows on a GT I wonder ?

Whilst waiting for my pal who is sadly almost always ill these days to come round to finish the brackets for my EPAS steering column, Ive been going round removing all the chrome trim and stripping the panels back to bare metal. the idea being to give them a temporary coat of primer for now until the weather improves when I can do a proper job.

Though the last owner had multiple new panels fitted and this was done extreemly well, Ive found the one place (each side) that the restorer never seemd to have got to. After removing the side windows i drilled out the rivets holding the chrome trim surround whch revealled small holes right in the corner.
My first attempt at welding this on one side using a self made repair panel was wasnt very good at all frankly. I do now have the use of a better mig welder though which should hopefully allow me to improve on this. The corner itself is very tight to work in and I'l need to do something better than the repair panels I made as they just arent a close and tight enough fit to allow the chrome trim to sit and clearance for the window to open and close.
Ive not been able to find very much information at all about repairing this area so Im assuming from this that some people at least probably just grind back the rusty edges, fill the void with fibreglass filler and refit the chrome without any ill effects. Personally I would far rather do this with metal if i can.
Does anyone happen to know please know if there is a source of repair panels for this job on a GT ?
1979 MGB GT
1999 Jaguar XKR
2003 MG TF
Ian F
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Re: BGT side window rear corner metalwork

Post by Ian F »

I find it difficult to visualise exactly what the holes look like, but I can offer the following (disregard if irrelevant!!).

For very small holes in an area of generally sound metal, I would usually clean back to bright steel, use a copper bar or block behind the panel, and simply fill with weld from a mig welder. It sounds as if cleaning up and grinding back might be awkward right in a corner, so getting a good molten pool would help to flatten the surface. A possibly easier way would be to fill small holes with Sifbronze, this is fluid at well below the temperature of molten steel, and is easier to dress afterwards. I use a carbon arc torch to get to the correct temperature.

Possibly just behind where you are working, the top joint of the rear wing often is a difficult corrosion area to deal with. There is a steel strip filling the joint on my BGT, presumably the same on yours.
The only way I found to deal with this was to run Sifbronze along the joints and thus seal the area, then apply wax underneath to seal that. The Sifbronze would require a bit of shaping to get the contours correct.

Ian F
MGCC member
1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, now sold
Not_Anumber
Posts: 414
Joined: Tue Sep 22, 2020 9:33 am
Forename: Chris
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Re: BGT side window rear corner metalwork

Post by Not_Anumber »

Once cleaned up, the hole on the driver's side in the corner of the area normally covered by the chrome trim, is about half an inch across. Pin holes like you describe wouldn't be much of an issue as they could just be filled with dots of weld and ground down. In the absence of available repair panels I will see if I can make and somehow hold a small plate in place from the inside and weld the edges of the hole to this from the outside then smooth off. Odd that the other side hasn't got a hole in this area though both sides will need the lip repaired and some repairs to the metalwork that makes up the inside ledge.
I do wonder how many GTs have something similar lurking under the chrome. I wouldn't have known about it otherwise
1979 MGB GT
1999 Jaguar XKR
2003 MG TF
Ian F
Posts: 1085
Joined: Fri Mar 27, 2015 8:18 am
Forename: Ian
Surname: F
MGCC Member: Yes

Re: BGT side window rear corner metalwork

Post by Ian F »

Chris,
a lump of copper might make this easier, even for a half inch hole. Conducts the heat away efficiently and weld won't adhere to it at all.
I have also used pop rivets to hold a repair piece in place, and then either melt out the aluminium or drill it out.Thete are small devices for sale which can hold sheet steel together from one side through eighth inch holes, but it's easier just to use pop rivets.

Ian F
MGCC member
1972 BGT, Blaze, Navy trim, recessed grill
1961 Midget, 948cc, now sold
Not_Anumber
Posts: 414
Joined: Tue Sep 22, 2020 9:33 am
Forename: Chris
Surname: S
Location: UK

Re: BGT side window rear corner metalwork

Post by Not_Anumber »

Thanks Ian those are really useful ideas. I will try just that.
I distracted myslef this with some jobs on the MGF instead this weekend as its outdoors and the weather was great but am expecting to have a serious onslaught on the B's window corner again next weekend.
1979 MGB GT
1999 Jaguar XKR
2003 MG TF
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