Check out my chin spoiler....criticism of technique encouraged

[BlackNDecker]

Wow, great progress BND. I like the shape, and it looks like you’ve done good work on the plug.
Duratec is a good choice for primer but I sometime just go to the local auto paint store and get high build polyester primer. This is pretty much what Duratec is (however they also have vinyl ester primer) and it can be wet sanded and polished. I’ve used PE primer for a number of plugs and had no problem making the mold.
Good flanges would also be important. There are a number of materials that can be used. Some use aluminum flashing, or plastic sheeting. I often use 1/16 balsa wood, though the wood either needs to be coated with the PE primer or what I do is cover the top with aluminum tape. I like balsa because it’s easy to get, cut, bend, and glue. I use hot melt glue to attach to the plug so in your case you could add a couple flanges to you plug and after one surface is molded, remove the flanges while leaving the mold in place and use the molded flange for the next piece of the mold.
One problem I ran into doing a full piece like yours, is making a provission for bonding the pieces together. Once you have the top and bottom pieces bonded (that is if they are molded separate), you will need to bond the back piece in place without things twisting or moving. I know there are a few ways to handle this but it is something to think about.

Jim, thanks for the feedback!

Yes, I am a bit worried about the complexity of the mold for this lip…I am anticipating a 3 piece affair.

I’m going to start by making lightweight molds of my rear doors so I can get acquainted with my compressor and the whole process before I tackle this project.

[Roger]

Great advice everyone! I really appreciate it.

I think I’m going to go with the duratec primer. I plan to purchase it from fibreglast.com once they send me a 20% discount code. This is the first time ever that I will be spraying paint with a compressor…so forgive me for asking basic questions, but here are a few that come to mind:

Do you think thinner (link below) will be necessary for the Duratec or will it be fine without thinning?
http://www.fibreglast.com/product/Duratec_Thinner_2306/Duratec

This 1.8 mm gun should work fine for primer, correct?
http://www.amazon.com/TCP-Global®-Brand-Professional-Regulator/dp/B001OZP0QO/ref=pd_sbs_auto_4

Duratec is the industry standard (at least the marine industry;)) for coating plugs. You don’t need the Duratec thinner, regular lacquer thinner works perfectly. Invest in a mixer (the kind you chuck into a drill) as the fillers settle. Mix thoroughly. Mix in the thinner. And don’t forget the catalyst. Depending on the temperature and size of the project, I’ll mix anywhere from one to two percent MEKP. Only catalyze one cup at a time and watch your time (ten to fifteen minute gel time). Strain the thinned and catalyzed primer into the cup. Promptly wash gun with lac thinner or acetone.

The gun you linked to should work fine The 1.8 mm tip is good for primer. You want to spray fairly wet or you’ll end up with a pebbled surface which requires a lot of sanding to smooth.

As for PVA on the mold, it works but the mold surface is nowhere near the quality of a mold built over a properly sanded and polished plug. If you prepare the plug with release agents, you should have no trouble with sticking. I’ve built hundreds of molds and never PVAed one of them. 6 to 8 coats of a mold release wax and the plug and mold should separate with a couple of wedges. Polymer release agents like Freecoat are also available.

[mugget]

I was going to say that you should look at the Duratec data sheet, but looks like Roger covered everything off fairly well!

Roger - if you were planning to spray more than one batch of Duratec, would you just spray thinners through the gun to clean it out, then set it aside and mix your 2nd batch? I mean is that sufficient to avoid anything gelling inside the gun? Or would it need to be fully cleaned (disassembled) after each batch?

[Roger]

It depends on the tempurature but if I have a big spray, I’ll generally run 2-3 cups before I wash the gun. By wash I mean run some thinner through it to remove the Duratec from the sides and top of the cup. Shake vigorously and then pull the trigger (no air) to flow the thinner through the fluid nozzle. The idea is to just get the gun pretty clean until you are done spraying. The film that builds up on the sides and top of the cup can gel before you are finished if you have a lot to spray. I think there is enough turbulence/flow in the fluid nozzle that it fairly well self cleans as you are spraying but it doesn’t hurt to run the thinner through it as a precaution. Continue spraying and cleaning like that until done, then do a thorough cleaning.

[muibubbles]

hands down duratec primer for the plug

[timj]

impressive, nice work

[BlackNDecker]

Thanks everyone, I will definitely be using the Duratec primer.

[muibubbles]

ps just revisited this… what kind of paint did you use for the bay? that stuff is fireeeeeeee!! blinding bright =)

[BSchmermund]

Nice work. I cant think of anything that you arent doing right.

And I thought the sawzall in the engine bay was the engine. Just kidding I have a love/hate relationship with you crazy Civic people.

[BlackNDecker]

ps just revisited this… what kind of paint did you use for the bay? that stuff is fireeeeeeee!! blinding bright =)

HOK Chartreuse neon yellow:
http://www.kolorhouse.com/hoc-ne508-q01.html

Nice work. I cant think of anything that you arent doing right.

And I thought the sawzall in the engine bay was the engine. Just kidding I have a love/hate relationship with you crazy Civic people.

I am expecting 300 flywheel hp from my naturally aspirated 2.4 liter 4 cylinder. Some people with full on race motors are getting over 400 hp (at the front tires) in naturally aspirated trim by stroking to 2.7 liters. Not bad in a car that weighs 2300 lbs.:eek: