Fiberglass question

In reply to Dusterbd13:

Couple of thoughts:

I know your bumping up against challenge budget. Gonna be quite a bit of materials to lay up enough glass to make them halfway durable.

My team member who had heart attack week before challenge last year then died a few weeks after was an automotive composite engineer who built several composite experimental planes (Vari EZ, LONG EX etc) would be a great resource but he ain't with us unfortunately. But he did help me with some repairs to our c4. Epoxy as opposed to fglass is much stronger but glass is easier to pull from mold. Cheap duct tape on metal is best to release. Making form from Styrofoam is easily shaped and you poir gasoline on foam when you're done and it melts away.

With those big IMSA flares you're gonna have to come up with some type of ribs underneath (glassed in balsa etc) for then to be half way durable.

Here's my goofy outside the box thought. If you just go with rounded flares as opposed to box flares, what if you got a large diameter inner tube...slightly larger than wheel opening when inflated. Stick inside opening protruding outside of fendet opening past where tire portrudes. Duct tape metal fender and duct tape tube in place so it doesn't shift. GLASS the e36 m3 out of it. Once you have a couple of layers dried, deflate tube, remove flare from fender and glass underside for strength. Rivet on car. Trim it so it looks purdy.

Capische? Not as sexy as Tshirt or curtains

Oh...another trick my composite buddy showed me...instead of using bondo or other non fg body filler, thoroughly mix resin/hardener with cornstarch to a thick smooth paste and use as a filler. Bonds/adheres with fiberglass much better than bondo. You can spread it just like body filler.

In reply to Ovid_and_Flem:

Great tips! Thanks!

Cost is my only holdup from going forward to be honest.

There is nothing wrong with the tee shirt idea to define the basic shape. Just add layers of glass mat after defining the shape.

Easiest way I know to strengthen the shape and add ribs is to use pieces of rubber hose on the back side- just glass over them. That's how I built the Mumpkin roof.

Actually, the tee shirt idea is an excellent one. It's much easier to stretch and define nice curves with a material like that.

Dusterbd13 wrote: In reply to Ovid_and_Flem: Great tips! Thanks! Cost is my only holdup from going forward to be honest.

Personally I like the big ol' wide skins hanging in the breeze...kinda like going commando

For a more finished look, trim the cut edges of fenderswith cheep black door edge trim.

If your glassing something up with the intention of making a smooth top surface, like starting with a form and glassing over it and removing the form, etc., once you have the top layer wetted out, put a sheet of plastic food wrap over it and smooth that out however you want (squeegee it, put a piece of flat wood over it, whatever, just get the plastic as smooth and flat as possible) and then let it dry. It will save a lot of effort with filler and sanding later.

If you can get the big inner tube, fiberglass the outer edges of it about halfway to the center on both sides. Deflate tube and remove, then cut your fiberglass donut in half, then down the center of each half. Bam, 4 matching fender flares. Trim to fit and add more layers filling in to the body.

I actually had planned to do something similar on my dune buggy back in the day, but with fat tires. My plan was to take an old tire, cut it into two half circles, then trim away most of the sidewalls and bolt the treads on as flares. I figured they wouldn't care about hitting stuff at least.

To save money, make a mold of the over fenders. There are numerous tutorials on the YouTubes.

The key here is only what's on the car counts towards the budget. The mold is a tool. Tools don't count. Only the fiberglass, resin, and paint will count.

I like that idea oldopelguy ! If I ever owned a hot rod I thought that using a half round sections of a tires and some bent steel brackets would make a terrific set of "tire tread" fenders and be pretty much invisible.

It has begun. Expect a hiw to thread like nocones when i don't fail.

Stupid question now that its probably too late.

Does resin expire? I mean, i found info on Google that it does, but i trust y'all more.

I was given 3/4 of a gallon of bondo fiberglass resin for free, and as its a challenge car.....

I tried to use some that was about five years old and half used and it never really hardened. It was new hardener so it has to be the resin.

In reply to Nick (Bo) Comstock:

Well, E36 M3. Guess i need to go buy a gallon. Hopefully i didn't screw up by starting with the old stuff. Do you k ow if fresh over top makes it better?

Dusterbd13 wrote: In reply to Nick (Bo) Comstock: Well, E36 M3. Guess i need to go buy a gallon. Hopefully i didn't screw up by starting with the old stuff. Do you k ow if fresh over top makes it better?

Never hardened. Still wet and sticky this morning. Will fresh resin over top cure my problem, or do i need to strip it all and start over?

In reply to Dusterbd13:

How many layers are on it now and how many will you be adding? I would guess if you put enough new layers on top to have the strength it will be fine but whatever you have on there now may delaminate and cause problems later on.

If it were me I would start over.

Single incomplete layer so far. Essentially started soaking the edges of my material.

Ill be adding a few layers of random strand mat yet, along eith reinforcement ribbing.

In reply to Dusterbd13:

Here's a how to on carbon fiber fenders.

You can probably accomplish the same thing with cardboard (if you only new a few) because they made some pretty spendy bucks with pretty spendy equipment. Principle is the same though.