Pulled FC sunroof; now what?
 

The FC sunroof mechanism is really heavy, and interfered with my headroom/rollbar installation so I removed it. Now I'm considering the options to fill the hole and was interested in how others solved this one. Likely possiblities are:

1) tack weld original panel into place and fill remaining gaps with Bondo.

2) rivet a composite panel in with rubber seal along perimeter

4) pray it doesn't rain

I'm mostly concerned about water leakage. Any clever solutions out there to full the sunroof hole?

Here is a pic just to make this thread more interesting.

if it were me id put the stock top panel in and make something to hold it inplace from inside using stock mounting locations. possibly silicone around the stock seals after.

do you dd this or is it strictly a track car.

hopefully dd, too good for track
clean full interior w/ cage, need i say more?

Well it's in between...for now. I'm not sure how you can tell about the interior condition from that pic, but it is in pretty decent shape. Sparco Milano's going in next.

I wouldn't use a TII as a dd since I'm constantly working on it, but many probably do. That's what a Lexus is for. I mostlly run autocross, mild track duty and play on weekends.

A very reasonable suggestion CHMel, it's just that the stock moonroof panel is 11 lbs and I'm hoping to cut that in half. A couple of ribs front to rear to tie into the stock panel studs would probably work well.

Funny, this is also on my current ToDo list for the track car - I also need the headroom.

I have seen some racers take two steel straps and drill them to match the short mounting bolts on the underside of the sunroof skin. Then you weld the front and back of the straps to the underside of the roof so that they support the original panel. You can bolt the panel down to the straps and later remove it if needed. Use RTV black to fill in the gaps around the opening.

Alternately, you can run two aluminum straps on the outside. Run them in parallel from front to back and drill and bolt them into the skin and the roof in front and back of the opening. Bevel the leading and trailing edges, use recessed heads on the bolts and paint to match the body. RTV the opening.

Good luck,

-b

on my 1st gen road racer:

I cut out most of the sunroof support braces from the main roof and the sunroof, and then reinstalled the sunroof, with it held in place in the 4 corners.

I then fiberglassed between the sunroof and the main roof, from the inside.

Then using a cutoff wheel, I cut away the 4 supports I had left in place. Then I fiberglassed over those 4 places, and I also made sure I sealed up and glassed over any water leak points. Finally, I poured some epoxy into the channel that was left between the main roof and the sunroof.

It has turned out real well. I did not have to repaint my roof; I didn't mess up the outer paint. I lost of LOT of weight that was high up in the chassis. I have one tiny pinhole leak if it rains real bad; not a big problem on a race car. I did this in the winter of 2000, and it still works great after 9 years of racing.

PS I have a stout roll cage that is tied to the roof and A piller and B pillar in multiple places. I also have a diagonal brace across the roof of my cage

find a FC in the junk yard with NO sunroof
bring a sawzall with 2 batteries with u (prefer dewalt)
kick the windshield out, start chopping, with some A and B pillars, shouldnt cost u more than $100
take it back home and trim it down
trace the trimmed piece to your roof
cut
weld
???
profit


thats how mine is done

^^I can post pics of his car in process. It the best way for a street car, a race car I would use some of the newer epoxies instead of welding.

Very creative solutions guys.
speedturn: good mention of cage tied to body. My concern with bonding using fiberglass only is the susceptibility to body flex. No welding is nice benefit.

sub9lulu: I'd need to find someone with mad welding skills to perform that major roof surgery. Sounds like a bit of work. Easily the lightest solution though, and would look super clean when finished.:icon_tup:. That black batmobile looks badass. More pics appreciated.

I took the stock sunroof, gutted it, spread the edges out and welded it back in place. Took forever, as I basically welded it with spot welds all around. Took a couple hours of welding, a quick hit here, a quick hit there. If I had to do it again I'd be really tempted to make a fiberglass copy of the stock part and put in some installation feet I could screw through into the roof substructure. That way I get the least weight up high (welds are alot thicker than you think, I bet i put 3 lbs or 4lbs of weight up there with the welding)

-Trent

Come on Trent, that would be half a spool of wire, or a whole small one!

Here is sub9's car, those spot welds were done in many stages to keep the metal from growing. Basically a spot weld at each corner, then in the middle of each pair you make until they are all touching. A wet rag helps remove the heat as fast as you can once the weld is done.

When I had a roof with a sunroof (which has since been replaced with a non sunroof roof, after my rollover), I basically gutted the sunroof of all the mechanisms, and used some aluminum brackets to attach it to the underside of the roof. no problems at all, since it very rarely rains in california, but if i were concerned, I'd have caulked it with some RTV.

hehe john how u doing
u still have those pictures saved !!!
i need to head to tampa and visit u... it looks more like a car now, lol

You must use small spools. I'm using 12 lb spools of wire in my Lincoln. Admittedly I shaved a fair bit off with the grinder in the cleanup phase. Still a complete pain in the butt.

-Trent

Is pop rivet an aluminum sheet over the hole too low-tech?

Did you bend the aluminum on an english wheel first?

Nope.

http://www.petting-zoo.net/photos/RX...IMG_2156-r.jpg
http://www.petting-zoo.net/photos/RX...IMG_2157-r.jpg

Throw some paint on that thing with a roller and call it done! Good enough for a track car.

Actually that riveted Al sheet looks like the lightest option I can imagine. And squirt some RTV around the edge to prevent leaks. Cosmetics are not too bad really. I like it, but I'm still evaluating more "elegant" solutions.

Wonder how fast you have to go to get the panel flapping (easy fix).

My gutted unbraced steel sunroof will flex pop down if the fat garage cat jumps on it. It pops right back up by itself after he gets off.
It does not flex and pop during a race. The air pressure inside the roof panel is a little higher than the air pressure on top of the roof, so the air is pushing the roof up a little (just the basic laws of aerodynamics.) Look at 99% of the convertible cars with their tops up that you see at interstate speeds, and their roof is bowed WAAAY up, not down.

Just did the aluminium plate and rivet deal on my 1st gen.
Not sure it will show well on this pic.
Will try to post a new picture later tonight.

Strictly Rotary

New pics of sunroof.
At first I tought I had used too many rivets but looking at other pics, it looks just right.

If I have to do it again I'll do the aluminum and rivets

The first time I did it I bent the rear lip forward to form a small shelf that the original sunroof would sit on. Then I tack welded the front lip and rear lip to the sun roof. I filled the gap with vacuum hose for a seal. That didn't keep out the rain so I tried to use silicone caulk. Unfortunately it always leaked but it looked just like a stock sunroof from the outside.

The second time I let my mechanic weld and bondo the sunroof into place because he was doing some other work on the car at the time and he warped the hell out of the roof. The car is a dark color so it's not so obvious but it doesn't leak and it looks acceptable for a race car.