Bonding Glass Doorskins

[Paul Schooley]

Anyone done this before? Got any pictures? Starting to put together the goodies for a lightweight/big motor combo. Have all winter to work on it.

[Zeke]

I assume you are bonding to the steel inner frame? Grind the flanges of the door frame bright and rough, then clean with acetone. Grind the backs of the skins to expose a llittle of the glass fibers by removing the glossy surface. (you will itch a lot, heh he) Do a dry positioning and decide on the clamping system you will use. Long, stiff boards or some steel sqaure tubing or some angle will be good on the bottom and along the window opening. Lots of little clamps on the sides. Use a couple of screws thru the skin into the metal to assure the location when you bond. You can repair the holes later.

Disassemble the mock up and butter both parts with the bonding agent you choose. Bondo containing fibers will work. Stuff in a tube from the body shop supply/paint store will be very good. Clamp up and wait.

[Paul Schooley]

Ya, bonding glass to steel inner door. Thanks. I'm also wondering if it's better to just buy full 'glass doors to begin with, thus reducing weight even further.

[roblav]

Paul,

I just replaced the sunroof on my car with a fiberglass part, bonded from the inside. I did all the prep work that Zeke says, but I used Hysol two part epoxy bonding agent. I've used that stuff to bond belly pans to my race cars, and it works really well. When I bonded the part, I used a combination of clamps and sheet metal screws from the bottom. I then ground down the screws on the top - and - voila.

[Paul Schooley]

The car will be a street machine, so I reckon I better bond the glass skin to the steel door for at least some protection. I was thinking only an early 911 hoop style roll bar for this. I'm also figuring on a 5-6 year project on a realistic basis (ya know...time...money...money...money....).

Also wondering if anyone has had any experience with the glass fenders. Do they crack easily under street use.

[RandyWebb]

"better to just buy full 'glass doors to begin with, thus reducing weight even further"
and "it's a street machine - possible roll hoop"

1st there is not much wt. savings from just replacing the thin steel skins with FG -- exactly how much I don't know - you could weight them on a postal scale and post here...

2nd - I would NEVER do this on a car unless I hada steel bar protecting me from side impacts - part of the roll cage will be fine, but most street cars don't have roll cages.

So if you put in a full cage, then go for full FG doors. Otherwise save wt elsewhere or trade the slight wt. penalty for your safety.

[Paul Schooley]

Hmmm...reckon you're right Randy. There won't be a full cage so I guess I'll leave the doors alone and concentrate on all the other components. Thanks for the advice.