Here are some pics of the last foam project I did to add a little flair to the stock HD Front Fender - and extend it.
Final paint was silver / blue - buried ghost flames w/ HOK Electric Blue Candy and Old School Flakes - Ghost Fire...

Nice extension, looks factory. Just curious, you mentioned Old School Flake. Did you add flake to your candy or did you dust it on with a dry Flake Buster gun? I'd like to try my hand with one of those dry guns sometime.

That's pretty cool! Could you show us the steps and materials involved?

Han - This is some stuff I took off the rack - should be most of what I use and for this particular job.
West Epoxy Resin 105 and fast 205 hardener - still takes an hour to cure - unlike fiberglass resin that kicks much faster (to me). I like the pump - idiot proof. To make the mix more flexible you can add more hardner - up to 10% - I know this is counter-intuitive but it leaves uncured hardener in the mix - more flexible - go figure. I (being cheap) use a lot of house plastic food cups as mixing bowls. The wider the base of the bowl the less heat and longer pot life.
All sorts of adding stuff. I have three different color pigments (red, black and white) to help me know where I am on the project for different layers. Pigment is nasty stuff and is a pain to get off - sticks to everything - very messy. I also use plain old Testors Paint (yellow / green / blue) for color as well. The 1/32" milled fiber is coarse and almost forms a mat - very strong but like oat meal to spread. Chopped fiber is fine - I used it for this project - Rsn: Easier to sand out and little strength was needed.
Sandable foam is in three thicknesses. I wait until Fiberglast has scraps on sale then buy. It sands / forms easily with 80 grit. it is NOT flexible so you need to cut scores in it from the back side (32" tooth hack saw blade) to get it around corners.
I used the West 403 adhesive to thicken the epoxy to attach it to the fender. Be careful where you join the foam with glue and not to "slop" it on - Rsn: It changes the consistency of the foam and makes shaping more difficult. Also remember in the end you add at least 1/8" of thickness to the piece (epxoy / epoxy primer, filler, 2k primer, paint, clear) so consider that when making the original foam peice.
I use epoxy primer - Valspar makes quart black / white - 1:1 mix. This keeps epoxy to epoxy. I also use epoxy filler - either paste from West Marine or thickend from the pump. On these specialty parts I'll stay all with epoxy straight to paint and not use 2k primer. If I do use poly filler I'll then go to 2k high build primer.
Lots of flux brushes - cut down to give some added stiffness, mixing sticks (I take "extree" from the coffee shop On disposable brushes the cheap ones are good for rough / underside work, but for finish work use the nylon so you're not chasing stray brissels all over the piece. Some things are worth paying a little extra for. I've taken the Pepsi Challenge from Home Depot, Lowes and Michaels and Michaels has the better prices.
Hope this isn't rambling.
Let me know if you have any specific questions. And most importantly this is what I do - how I do it. I'm not by any means an expert. The methods we all use are different and I'm not a chemist - just to not get into a flame war.

Darrelk,
Here is the HOK stuff I used - with Kirker (god forbid Mira Clear (remeber the cheap reference above).
On the flakes, I add it to the clear, open the gun - first coat and hit it HARD!!! Don't be skeerd - The flakes can smell fear. If you try to dust it they "lay" on top and it takes too many coats to bury them. I was surprised how they seem to even out themselves with just good basic gun control technique. The old school (white powder looking) can be sanded - unlike the metal ones.
Make sure you take the gun screen out - flakes won't go through it and you wonder what the 'eff is going on - Yes, I've done it...
If you bury them in tinted clear they do lose some brightness. But I wanted tinted clear and really like the way HOK Blue Candy came out. Also If I tinted the clear, then added flakes, then buried them in straight clear - waaaaay too much product piled on.
The tins (fenders and tank) were easy to spray being relatively flat / straight. So flake was even.
I just sprayed a guitar which was not with straight clear / flake and I'll see how that comes out.
Remember as a painter, I'm a good fab guy - hence the 80-Grit...

Thanks for the details. You do stuff very much like I do. I've been doing almost everything with West epoxies lately. Good idea about buying Fibergalst's foam scraps. Yeah, I'm from a woodworking background so I figured early on that "back kerfing" almost anything will allow you to bend it. I even do it on body kits to move stuff without cutting a part out or completely through.
I was just wondering about the Old School Flake. On the last flames I did I used the HOK intercoat clear as my flake carrier. Always on the lookout for better ways and methods to apply flake. Hey, if you get a chance check out this website...
www.paintwithpearl.com
Just about the best pricing I've found on flakes, pearls, etc. and the quality is quite good.

Yes, thanks for details. I could see myself doing something similar.
I know of a few high-end cue builders that use West System products.
Must be good stuff.

DarrelK - Neat site - seen their stuff, but never used. Their prices are better the hok, which BTW are VERY proud of their stuff
With what little I use, it could be a lifetime supply.
I use this a lot - Nate is very helpful
http://www.innate.com.
Thanks for the "back kerfing" term - never knew it had a name. And here I thought I invented it!!! I need formal education and training!!!
BTW - never had the patience for woodworking WAAAAAAY too much skill involved. Made two projects (refinished an oak desk and made a matching shelve) and it drove 'effin me nuts!!! Everything has to be perfect!!! UGH!!!
Now I get it within "caulking" tolerance and paint
Here is a pic on the finished fender. Only problem is the small flakes don't come through...

Yeah, I've talked to Nate a few times and bought stuff from them. Good cutting edge company with fast service.
Woodworking does drive a lot of guys a little nuts. That's what keeps us in business though, .
I know what you mean about that small flake thing. My Finale kit is done in Auto Air's Sparklescent Rock Star Red which is a micro flake. In low sun conditions you can't see the flake at all but in full sun they'll burn holes in your eyes. I got a surprise in the early evening at a car cruise at our local Hooters this summer. Their high pressure sodium lights came on and it looked like tiny fireflys were all over my car. I've never seen flake have quite that reaction under artificial lights like that. Werid, but cool, .

Nice 80!

Great write up as well.

what happens if someone poked their finger hard into the foam area of the fender now? It looks nice though.

btw guys.. foam only is compatible with epoxy resins. polyester or vinylester resins will melt the foam.