Have a floorboard issue (see photos.) There are a couple of cracks and wanted to re-glass the floor. I’ve never attempted fiberglassing before but I’m pretty sure I can handle it, especially hidden under the carpet ;-) I'm pretty sure you’re supposed to use epoxy resin for the bodywork but figured I could use the polyester resin for this job (cost considerations for a rookie.) Any comments or opinions? Second half of the post; what do y’all think about using something like Reflectix as a core between two layers of glass mat? Maybe stop some heat on the outside?

 

Sure you can fiberglass that, just get it really clean first. I used a brushwheel and then acid etched the floor and glassed it in. 2 layers on top and 1 on the bottom. Reflectix I wouldn't do as an inner layer, the glass might eat it and it is also somewhat spongy. You need solid for the glass. Reflectix on top after its set and painted will be fine

 

Thanks. Should I cut out that old 'flap' of glass and start from scratch, or use that broken piece to hold everything in line? It's not completely broken off, it's still connected under the accelerator pedal.

 

Get the pedals out of the way, all 4. I know, it's a real pain, but do it. You'll be thankfull you did. Clean any old crap out,old repairs, including whatever that is in the crack. After it's clean, don't acid etch or any other chemical on it except for some MEK, toluene, or good old laquer thinner to wipe it down, Wipe it down, not soak it with a half gallon. It needs to be clean and dry. If you have spots, holes, etc. that you can see through, use some aluminum tape on the underside to cover those holes.
If, by chance, you could find some PVA at a 'glass shop, get a few square feet. (PVA=poly vinyl alcohol) It's greenish saran wrap looking stuff, just a bit thicker. Cut your inside repair fiberglass cloth about an inch bigger all around than the cracks, ect. Cut a second layer about an inch or so bigger than the first, and then a third layer. Lay out the cloth, medium weave, on the PVA, or some aluminum foil if that's what you have. It'll work, no matter. Mix the resin and hardner. Have a 1" brush handy. Brush the aluminum foil with resin, then lay the first layer on it. coat the top of the cloth with resin until it's wet, not dripping. Oh, you should have some gloves on when you start this. Take the 1st layer and place it right where you want it, do the same for the 2nd and 3rd layers. Make sure that you have minimal air bubbles, and WALK AWAY and leave it alone. Let it cure for at least an hour. Once cured, remove the tape from the outside of the floor, and make sure it is already cleaned and wiped down at the same time you do the inside. Now you can do the same thing again on the underside, yes it will stick if you do like I just told you to do. Remember, clean, clean, clean, 3 layers, each a bit bigger than the one under it, not too much resin, and WALK AWAY after it's done and let it cure.

Let us know how it goes.


BBTank

 

I now have to go out of town for a bit so it'll be 2 weeks until I can get to it... grrr. I'll let you know how it goes when i get to it. Then there's the wiring replacement, brake rebuild, engine drop, etc, etc...

 

i did this exact repair on my 70. i used cloth, not mat because the cloth will bend and flex to fit the curves of the floor.

 

Matte is even more flexable than cloth. Once the matte is wet with resin, you could almost make a 3" ball out of it. Matte is also alot stronger than cloth, due to the multi-directional strands and the amount of different strands. Cloth is 2 directional.

Not just disagreeing to be stubborn, I started doing composite repair right after I came in the Air Force in 75.

 

I already have some matte i plan on playing around with prior to doing the repair. Figured I could use that for the strength in the main part of the crack and feather out to smooth things with some thinner cloth. I'll prob try a little 'fabrication' to get used to working with this stuff before diving into the repair. I really appreciate the input; here and in other threads. I'm tired of looking at this car in the garage and want to get it back on the road. I couldn't afford or have the confidence to do it without all the help from you guys.

 

Unless you already have the thinner cloth, don't bother with it, just sand half way smooth on the inside and outside repairs, and let it go. Now, I don't mean too rough, I mean half way smooth. You're going to put insulating material of some sort down, then carpet. You'll never acheive a "never repaired before" finish, so don't go too far overboard. The underside should be covered with the heat shield plate (the metal one) and the inside with carpet. Post up some pics of the progress, keep us informed.


BBTank

 

I had some cracks near my tranny tunnel and seat. It's all in the prep, however, after you lay the glass, smooth it out so you get rid of any bubbles in and the like. They say you should go out 4 inches in every direction from the crack as well.

 

A lot of good advice already posted, but I'll add this.

V out your visable cracks to nothing but at least 2" wide.

Final clean with starter fluid and let all the dirty fluid run thru the cracks out of the car. Continue until the runoff fluid is clean.

Install narrow strips first and go wider until past the v'ed out area.

As far as glass, here is a quote

Mat has the least strength with plain cloth being next stronger and so on. At any rate, it is cheap only a buck or two at most per yard x 50" wide.

Countless examples in a search
http://www.fiberglasswarehouse.com/f...nformation.php

Considering strength, the biggest mistake most people make, is having a ratio of resin to glass far to high. Only the glass should be saturated and no extra resin. When using mat, most people have far too much resin and it is useless by itself.
For a beginner especially, cloth is much easier.

Use epoxy period. This is very important.

If in Ft Lauderdale or St Pete, you can get this stuff pretty cheap or even mail order. Precise mix with the pumps.

Google the addresses from the labels on the jugs in the pic.



Here is an example of how clean you should get the old glass.

 

MyRed69,

Please note that noonie gave some very good advice. In the area that you live, marine repair centers may be a source of materials and info for you.
Epoxy resin is stronger that polyester resin but, more expensive. Keep in mind that most pleasure craft boat hulls are polyester.
Mat is great for filling rough surfaces because it's easy to work it in and get the air bubbles out. If an area that you made into a V needs to be leveled, you can tear off some mat and work it in. You need to place layers of cloth over the mat for strength. Mat by itself is rather weak unless it’s a very heavy mat, it goes by the ounce. Woven mat is heavy duty and very strong. I used that on work boats that need to break skim ice in the winter (mat/woven cloth/cloth). Use enough resin to completely saturate the material, the resin just by itself is brittle. It was said before; work the air bubbles out at each level of material. Make sure you mix the hardener in the correct amount and watch your working time. The resin in a container may kick off sooner that you think due to the heat from the chemical reaction.

 

Thanks for all the advice; it sure helps with building the confidence level. I located Fiberglass coatings in St. Pete, kind of a double edged sword though; now the wife wants resin table tops built… I the pic the red lines show the extent of the cracks (larger of course than originally thought.) I’ll remove the splash shield bolt rivets and reinstall after glassing. Hopefully the bolts will still be long enough to attach the splash shields to. I plan on running the glass all the way up to where the steering column starts, back to where the rise is for the seats, up the side of the tunnel, and up to the kick panel as far as I can, then the same on the outside. So it seems one piece is not the way to go? I figured larger pieces would be stronger, not the case? Thanks again for the help…