Thoughts on Fiberglass Rear-Skirt Design

[stevey_frac]

Originally Posted by evolutionmovement

I would also think aluminum would be the quickest and lightest solution. I guess I'll find out if I try it on my wagon whenever I finish restoring it.

The aluminum would have to be bent out on my car to accomodate the rubber especially if the tire is allowed to go down. I don't have the ability to form aluminum to be the way i would want it. I agree that it would be fast and easy if you could put a flat panel on it though.

[MetroMPG]

My comments, from having made fiberglass front wheel skirts and Kammback:

- Use epoxy resin, rather than polyester. It's much more expensive, but also stronger. (I didn't. Wish I had.)

- if you want a pro finish, 90% of your time will be spent doing cosmetic work (sanding/fairing body filler) to smooth the fiberglass part once it has been made

Lessons learned:

- In addition to using the weaker polyester resin, I didn't make my front skirt thick enough. So it's gone a bit wavy. When it was initially completed, it was smooth & nice. I need to reinforce it with more layers on the back, and possibly re-fair the front side.

I've been buying my supplies at Crappy Tire. It's not cheap! And I'm not sure if I can get the epoxy resin there (may have to go to a marine supply store.)

[stevey_frac]

Uh ohh... Looky what i found....

Bondo Resin Repair Kit, 1 L | Canadian Tire

Might not be a bad place to start. I just need some foam insulation to make my plug. Might take a run at it this weekend.

Did anyone else think that fibreglass was more expensive?

[stevey_frac]

I'm looking into a local canadian company that sells fibreglass materials. I'm going to see if they'll sell small amounts locally, and what it would cost. ZAt the moment, i'm thinking it'll run around $70 for a set in materials alone, and as MetroMPG indicated... Probably many hours of work to get a profesional product.

-Steve

P.S. The company is called Rayplex.

[Bicycle Bob]

Why does everybody just try to fill the hole, and put up with whatever flare shapes the stylist did? With fiberglass, you want a convex shape for stiffness, and it will smoothly cover the whole mess around the wheel and as far back as necessary. Mold making is more tedious than mysterious, especially for that shape. If the available holes are insufficient, with the right adhesive, you can probably put mounting blocks around the wheelwell without damaging the paint, if you are worried about resale value.

[stevey_frac]

Originally Posted by Bicycle Bob

Why does everybody just try to fill the hole, and put up with whatever flare shapes the stylist did? With fiberglass, you want a convex shape for stiffness, and it will smoothly cover the whole mess around the wheel and as far back as necessary. Mold making is more tedious than mysterious, especially for that shape. If the available holes are insufficient, with the right adhesive, you can probably put mounting blocks around the wheelwell without damaging the paint, if you are worried about resale value.

I'm not quite sure i understand what your saying. You want me to use the wheel wells for... i'm not even sure. I want to put a skirt in place that will cover the back wheels from the bottom of the car body, to the top of the wheel well. It has to bubble out a bit to do this. That's a convex shape...

Please explain, as i'm feeling more then a little lost here.

-Steve

[Bicycle Bob]

On your car, I believe that the rear tires project beyond the lower edges of the fender, na? Depending on the suspension softness, etc, I'd start to define my new shape by taping blocks about 2cm thick on to the tire, and bending splines smoothy over them to where they meet the body. I'd use a gentle curve, probably going at least 10 cm past the wheel opening in all directions, and much farther near the lower edge. Starting from the bottom, you can work up and make a shape that takes a smooth vertical spline. Where the edge of the skirt meets ridges on the body, you can either use a jagged (coped) edge, or blend the shapes. You want to get a nice-looking edge shape overall by varying the curve in the splines somewhat as you go up.

[cfg83]

stevey_frac -

Here's something with a tiny(?) chance of working. Research aftermarket wheel skirts for old classic hot rods. if your wheel-well dimensions are close enough, you may be able to adapt a "classic" wheel skirt.

While Googling for an example, I found this how-to article :

Creating Fender Skirts - Rod And Custom Magazine

Very few single elements can separate a rod from a custom, but one item tops the list of making a custom a custom, and the element that most screams "custom" has to be a pair of fender skirts. Back in the '40s and '50s, skirts were readily available at local auto parts stores, but today original skirts have skyrocketed in price and have become nearly impossible to find for the early models. Customizers from the very beginning have mixed pieces from different makes and models to enhance the lines and looks of their rides, so of course just popping on a set of original skirts would be out of the question. Early customizers preferred the sweeping bubble skirts from high-end models like Lincolns, Buicks, and Chryslers, and later the Mercury Turnpike Cruiser skirt became a must-have item.

The 1936 Ford has always been a favorite fodder of customizers, and the skirt of choice was the graceful teardrop-shaped bubble skirt used on Lincoln Zephyrs from the same period. This style of skirt has long been on the "unobtanium" list, so making a pair from scratch has become the best answer to achieving custom nirvana.

We followed along as a pair of Zephyr-style skirts were made for a '36 Ford and we were surprised how relatively easy the project was given the stunning results. Note that the technique used is close to the same process used when reskinning a vehicle door, and the tools required are the same ones found in the shops of most do-it-yourself customizers.

CarloSW2

[stevey_frac]

Originally Posted by Bicycle Bob

On your car, I believe that the rear tires project beyond the lower edges of the fender, na? Depending on the suspension softness, etc, I'd start to define my new shape by taping blocks about 2cm thick on to the tire, and bending splines smoothy over them to where they meet the body. I'd use a gentle curve, probably going at least 10 cm past the wheel opening in all directions, and much farther near the lower edge. Starting from the bottom, you can work up and make a shape that takes a smooth vertical spline. Where the edge of the skirt meets ridges on the body, you can either use a jagged (coped) edge, or blend the shapes. You want to get a nice-looking edge shape overall by varying the curve in the splines somewhat as you go up.

That sounds a LOT more complicated then i want to do. I am thinking i'll build up from around the existing edge (there is about a 1 inch ledge around the wheel that is flat) and build it up enough that it clears everything, probably around 2 inches. That transition can be fairly subtle. I was planning on the main part of it being flat, and parallel to the existing ledge. The 3d sculpting your talking about I think would be too much for my engineer brain to do properly. Keep in mind i'm a computer geek. I have the fine motor control of a spastic 2 year old.


EDIT: Wait.. i re-read that, and i know what your going for. It'd be fairly sexy, and not nearly as much art as i thought it was. :P

[MetroMPG]

Originally Posted by stevey_frac

Uh ohh... Looky what i found....

Bondo Resin Repair Kit, 1 L | Canadian Tire

That'll be the polyester resin. You want epoxy - it'll say so explicitly on the packaging.