Old Project Revitalized - 56 Track Car

Preparing molds for aero "side curtains" to direct airflow outside of the front wheels - creates a low pressure outside the wheel which helps pull brake cooling air from inside the wheel. Also helps smooth airflow down the side of the car.Aero - Curtain 3.jpgAero - Curtain 2.jpg
 
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What is the next step? Fiberglass the taped surface?

I'm really interested in what you are doing. I will have some similar things to do with my car.
 
What is the next step? Fiberglass the taped surface?

I'm really interested in what you are doing. I will have some similar things to do with my car.
Yes, I will fiberglass the taped areas. That then becomes a male mold which I will finish sand, wax, coat with mold release, and pull a finished fiberglass part off of the outside. That gives me a smooth finish for the exposed surface of the duct which I will then glass in place in the air dam. I'll take a couple of photos as I go.
 
Okay, as promised. Here I glassed the inside of the poster board and tape soft molds, then peeled off the paper mold (previously waxed and covered with PVA. The difficult part is achieving symmetry. Since the soft molds are not super precise, it takes some grinding and filling on the resulting fiberglass molds to make them exactly the same. Now I will finish sand the molds, wax and PVA them, and pull the final parts off the outside of the molds. This will give me a smooth exposed surface of the parts that I will then glass into the air dam. The smoother the mold, the less finish work you have to do once the parts are installed.

Aero - Curtain 4.jpgAero - Curtain 5.jpgAero - Curtain 6.jpg
 
Is the poster board under the fiberglass mat?
The poster board is under the yellow tape. I just formed the scoop out of taped together pieces of poster board, then covered the whole thing in tape to give it some rigidity. Then I covered the yellow tape with clear plastic boxing tape which releases the fiberglass resin much easier than the masking tape. Finally, I waxed the clear tape and put on a final coat of PVA as a mold release agent. Once the fiberglass cured, all of the tape and poster board just pealed off the back side with no effort . The tape does leave some lines in the fiberglass, but they are shallow and easy to sand out. Here is a photo of a poster board and tape buck I used when I built the fender flares for my Focus track car, to give you and idea of the build-up.

Focus FF 4.jpg
 

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Pappy - I "shoot" my PVA using a Prevailer setup. It is small and usually just the right size and one less gun to clean.
For the big parts I do use the compressor and guns.
Using a spray application for the PVA keeps from lifting the wax. You knew that, but others here ready to practice might not.
Tips as we go. Nice work on the fender flare setup.

Cheers - Jim
 
Finally got around to putting the first coat of primer on the modified air dam. It looks very functional - ducts for air curtains and a small vertical Gurney lip in front of each tire to help create a low pressure outside the wheel.Air Dam 1.jpgAir Dam 2.jpgAir Dam 3.jpgAir Dam 4.jpg
 
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