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I did some fiberglass work over the weekend, but I am realizing a day later that I probably did not mix the catalyst well in my last layer of resin. The patch is over my passenger side floor, and only parts of the floor are hard now, the rest is still spongy and tacky.

Is there any way to fix this, and how? Should I mix some catalyst in some more resin and put that on top of the "uncured" parts? Any good resources for beginner fiberglass work (in applications like strengthening fiberglass fenders, hoods, etc) would be great.

Thanks in advance.

Oh...so I guess I did it wrong. Catalyst goes in *all* the resin you use, not just top coat. I don't know why I thought that would work.

Any chances for fixing, or should I just rip it off and start over? Also, should I start with a layer of resin, or fiberglass?

Nameless.

Sorry for the delay - I've been out of town.


The Catalyst causes a chemical reaction on your resin -- it will heat up.

I'm most intersted in solid repairs.. You'll get tons of answers on how to repair with glass.. much of this is opinion, exeperience, space and tool.s

• 1-Remove all paint
  2-Rough up the area
  3-Paint Brush on a layer of 2part resin
  4-Lay on a layer of mat
  5-Paint on More resin...
  6-More Mat

Repeat steps 5 and 6 until it's thick enough.. end with a painted layer of mat.

Note.. there are different types of mat.

I've found that sanding disks make quick work of prep.

Tim

Prep was attack with wire wheel, then we cleaned thoroughly with muriatic acid/water. Using sanding discs for the fenders, definitely works well.

What do you mean by 2part resin?

Thinking I may just go over the messed up floor with another layer of mat, and some properly mixed resin with catalyst, at least to harden the top layer, and this is just to water proof the floor for now. This is really only temporary, to fill in lots of little holes until I can afford a new complete floor pan for the passenger side of my car, and have time to install it. So a hack job is okay, I just need a harder floor hehe.

http://www.uscomposites.com/mat.html
I went with 1-1/2 oz chopped strand mat, using a polyester resin.

2 Part meaning Resin and activator.

I'd remove it and start over.

Dumb question .. when you use the Hydrochloric acid prep.. what do you do to neutralize the pH back to 7?

Tim

another thing to note when you catalyze your resin: don't add more catalyst than absolutely necessary. Yes it will speed up the reaction, but it will overheat the resin and cause microscopic cracks that will weaken the layup.

I agree with Tim; tear it all out and chalk it up to learning. You're doing fine, though (I've forgotten to catalyze resin altogether, but don't tell nobody).

Here's a friendly layup sequence: two-ounce mat is actually made up of two one-ounce mats bonded together. You can take them apart and they will conform to just about any shape individually. Do a layup with three one-ounce mats and one six-ounce cloth (the cloth is optional, but if you don't do it use another three or so layers of the mat). The cloth is considerably harder to shape, so pre-fit it and cut it up while everything is dry if you have to seam it.

Also, use JUST ENOUGH resin to wet out the fiberglass. When you lay down the next layer, try and get the excess resin from the first layer to bleed up before you add more resin. Then, when you're done doing your layup, squeegee every bit of resin that you can get out of the layup. Resin is brittle and weak; it's the fiberglass that is strong. The resin is there just to "glue" it all together. Get as much resin out as possible. The dryer and denser you can make it, the better the layup will be (just make sure everything is wet enough to create a bond when you're laying it up).

Bear in mind....ALL....fiberglass attached to metal, or bondo attached to metal...will eventually fail via absorbing water. Its inevitable. Its the chemistry.
If you have the time....I would use some of Eastwoods low temp, lead free body solder. It will never rust, absorb moisture or fail. Ray

Bear in mind....ALL....fiberglass attached to metal, or bondo attached to metal...will eventually fail via absorbing water. Its inevitable. Its the chemistry.

Absolutely true. Then again, if the fiberglass layup is done correctly the time to complete failure can be quite long. If it's a means to defer a pan replacement until funds permit, I'd give it a shot. I wouldn't consider it a permanent solution, though (but then again, what's permanent on a Baja bug in inclement weather?).

If you have the time....I would use some of Eastwoods low temp, lead free body solder. It will never rust, absorb moisture or fail.

I have mixed emotions on that one, but it's only due to the application. First is cost. At $290 or so for the kit (and you sort of need it if you're starting from scratch), it's extremely expensive for this kind of fix--more than replacement pan halves. And for the record, you can pop-rivet pan halves in place. Back in the bad old days I did it on my old squeeze's '70 and it worked great. No, it's not the factory-approved method either, but that's another story.

Then there's also the tool requirement. I know a propane torch will melt the standard 70/30 lead filler, but it melts at a low temperature like 400 degrees F. The lead-free stuff melts at a considerably higher temperature. I know a hand-held propane torch will melt the lead-free, but I don't know if it would sufficiently maintain the higher working temperature over a larger area. I'd say that's a job for an acetylene kit and i have it on good authority that the technician endowed with Franz' care doesn't have one.

No, it's not the best way to patch metal with fiberglass; however, if done properly and done with the understanding that it's a permanent fix I think it would be fine for a long time coming.

I should've added this to my last post, but I just thought of something that might be a very effective fix.

The new generation of epoxies for automotive body use is amazing. I would give it a good consideration if you want to bond some fresh tin to the area in question. Heck, you could use that cheesy 24-gauge steel the local True Value hardware store stocks.

Here's a similar application that has held up for a few years now on an exterior body panel. A very good friend of mine is a pro collision repair tech. He did a wham-bam job on a friend's truck that needed fenders. The new fenders had unwanted trim holes, so he dimpled the holes and "filled" them by bonding postage stamp-sized steel swatches to the backside of the holes and leveled the frontside of the dimpled area with more epoxy. Everybody had a few good laughs and wagered how long the "fix" would last and to their surprise everything looks good so far. It hasn't even shrunk.

If it's good enough for the manufacturers to specify when bonding steel panels together on new cars, I'd imagine it would work just fine on old VW tin. It certainly worked on that truck so far.

Just another option...

I should have read more carefully the first post. I forgot that you are working on pans. Fiberglass and sheet metal with rivets are not a big deal with pans. I agree with the method now.

For all other body work...visible outside bodywork...I would not use fiberglass or bondo. Generally by the time this stuff starts leaking and pulling in moisture....and also by the time you get around to fixing it...much more damage is done to adjacent metal.

Also bear in mind that this comes from the perspective of someone who drives and works on a type 4 and not a bug.
In comparison...body parts for bugs are a dime a dozen. Body parts for a 411/412 do not grow on trees.....so $290 for the starter kit is only a little more than one clean fender or door might cost for me if I'm lucky.

By the way...depending on what tools you already have....you o not need the kit. You need a propane torch with a fan spreader for the flame and a few other attachments, and a small peizo butnae torch helps too...and normal body tools for sanding and grinding.

This is why you use the non-leaded version. It has a relatively low melt point and can be sanded normally. Ray

ditto on fiberglassing pans.. CUT OUT all the bad rust.. do not leave it under your fiberglass..

DO NOT do this on body steel.

Sorry for the short and curt post - leaving in 2 minutes.

I just got back from Minneapolis Friday. Nice place! Ray

Next time PM me.. I'll show you around.

MPLS is like Seattle without all that nice weather.

Just saw that there were some additional thoughts to all this, thanks. I ended up not peeling out the layer of fiberglass because I don't think I would be able to get it out! The floor pan was clean, but certainly not smooth. I put a properly catalyzed layer of resin over it...not a great idea, but I think I will also put another sheet of the fiberglass.

Thanks for the tips about squeegeeing and stuff. Geez is that a word? Yes, this is a temporary solution, for as long as I can get away with it, and until I have a place to store a half floor pan and time to install it (and a welder).

My funds are limited because I am a college student and need to pay rent and food. Working fulltime right now, but most of the money I am saving up for engine work and to help my parents out as they are paying tuition, I am just paying to live. And again, because of working fulltime, don't really have time to deal with the floor pan. I really wish I did.