Body Work??

[sweeteffx]

Ok, I've seen people that mold their whole body kit, or hood scoops etc. Fiberglass molded to metal, good idea or bad idea? I think it would crack and evenutlaly fall apart. Or, is there some process in which this should be done to prevent such an action from occuring? Thoughts/ideas?

[m pwrd 3]

Bad Idea very bad in my opinion.

Reasons:

1. Looks Tacky

2. If you hit a opossum or something with your front bumper the whole front of your car will have to be redone

3. If not done correctly it will crack and bubble like crazy.

4. HEAVY

[xjoewhitex]

ok... i think if you do this right you can have it looking good and have it strong so it won't crack apart.. theres a couple of different steps in doing it.. and you gotta do it right for it to work.. ive seen good jobs and ive seen bad jobs....

but either way... If something happens like jamie said and you hit something its going to break into pieces... i seriously wouldnt mess with it.. 8)

[Jay]

Ok, I've seen people that mold their whole body kit, or hood scoops etc. Fiberglass molded to metal, good idea or bad idea? I think it would crack and evenutlaly fall apart. Or, is there some process in which this should be done to prevent such an action from occuring? Thoughts/ideas?

strip the part of the body down that will be covered in glass to the bare metal, this makes for better holding. really you dont have to worry about it cracking all that bad, but i really dont suggest it cause if an when you do hit something ect. and have to replace a sideskirt then it isnt just simply replacing it.. it's a pain in the ass.

[Feedman]

Agreed...

Strength comes in layers....

As with painting...prepping makes or breaks a good project...

Take your time and it should turn out ok....practice makes perfect.... 8)

[sweeteffx]

I started molding a roof scoop on, I used pop rivets soo many you could lift the car by it. Anyway, I started with dura-glass (fiber/bondo mix?) then i didnt get enough around the front and i left it fora couple days, well, it cracked. Then i covered it up with a layer of bondo and the back cracked. soo.. yea.. what would you recomend?

[Jay]

did you keep it in a climate controlled area while it dried? if not that would explain it cracking.. if you stripped it down to the metal it shouldnt of cracked, that really doesnt make much sense.. once you get the 1st layer of glass on wait til it sets up then airfile it down, that should make you a good base, after that bondo would be easier to work with as far as feather edging

[Feedman]

I would say it was put on to thick.....?

Thin layers...sorta like paiting....... 8)

[narfdanarf]

too much bondo=crack city

[sweeteffx]

So, I should do it slowly and not try to put it all on in one big layer? I would have thought aht if you could put it all on in one layer then it would hold better? Are you saying that lots of small layers would be the best? Should I also sand it to near smoothe everytime, or should i leave it rough for a better surface for it to stick to?

[Jay]

you tried to do it all at once? uhh yea thats why it cracked. you shouldnt have to sand it every time, it depends on how smooth you lay it down really.. your last few times you will want to tho cause it makes for easier feather edging

[sweeteffx]

Do you think that it would be worth the time to sand it back down and build up again slowly using as much of just the "Bond-O-Glass" then just use the body filler just sort of like a glaze over it to finish it off? or, would it be good just to build a little more over top of what's there and it should hold? What should I do since its 70% molded now.

[Feedman]

Do you think that it would be worth the time to sand it back down and build up again slowly using as much of just the "Bond-O-Glass" then just use the body filler just sort of like a glaze over it to finish it off? or, would it be good just to build a little more over top of what's there and it should hold? What should I do since its 70% molded now.


Start over..... 8)

[Jay]

Do you think that it would be worth the time to sand it back down and build up again slowly using as much of just the "Bond-O-Glass" then just use the body filler just sort of like a glaze over it to finish it off? or, would it be good just to build a little more over top of what's there and it should hold? What should I do since its 70% molded now.


Start over..... 8)

yea I agree w/Adam id just strip it off an start over.. sounds like you put it too thick too soon an it started cracking when it cured. You could go over what is allready there, it isnt going to crack anymore, or shouldnt at least.. but I think you may be ahead to just redo it completely. up to you

[sweeteffx]

Should I use as much of the bond-0-glass as possible or just the body filler? I wnat to know what will be the most durable. and i dont need it cracking on my roof.

[daveb91]

I know some guys who tried to fill in a CRX sunroof and bought the plug and tried to duraglass it in and it kept cracking from the flex in the roof. Dont know if this is what your running into though.

[sweeteffx]

I dont know if it's the fact that the roof flexes, or weather its just the weather and the fact that I havent put it on thick enough. The thicker i get it, the less the possibility of it flexing/cracking correct? where it cracked, i think that i just simply didnt put enough on it. or i put too much on it too quickly like someone said earlier.

[Feedman]

The flex in the roof isn't going to make your job any easier.....is there someway you could stiffin it?

A controlled enviroment would help.....let it dry slowly.... 8)

[RobbieNelson]

POST SOME PICS!!!!! I wanna see what y'all are discussing!!!

[Feedman]

POST SOME PICS!!!!! I wanna see what y'all are discussing!!!


Ditto..... 8)

[daveb91]

I think we already said thicker layers are not better. How about actually using fiberglass sheets?

[xjoewhitex]

POST SOME PICS!!!!! I wanna see what y'all are discussing!!!


Ditto..... 8) yea i guess that would help... :wink:

[sweeteffx]

Here ya go. There's only one crack you can really see in the picture. so here it is. There's a picture of the overall look too. There's a little bit of surface rust on the edge where I didnt get enough primer and because of all the rain I've not done any work to it. Rain isnt a good thing.


http://www.geocities.com/sweeteffx/crack.jpg
http://www.geocities.com/sweeteffx/all.jpg

[Feedman]

Should I use as much of the bond-0-glass as possible or just the body filler? I wnat to know what will be the most durable. and i dont need it cracking on my roof.


Whats the difference in the two???

8)

[Jay]

ones glass an ones not

[Feedman]

ones glass an ones not


Ok, whats teh pro/cons of the two?

8)

[sweeteffx]

If I'm not mistaken they should be

bondo-glass - should be lighter, but the bondo makes it weigh a ton. and should be a little more flexible and a bit stronger because of fiberglass strands.

body filler - heavy and i spose it cracks or breaks out when you try to flex it. But, it isnt as thick, and it feathers a little easier for making it all flush in the end.

Am I correct?

[daveb91]

Just use actual fiberglass its not that hard to work with and it will be stronger. then use bondo as a skim coat to smooth it out.

[Feedman]

Just use actual fiberglass its not that hard to work with and it will be stronger. then use bondo as a skim coat to smooth it out.


That sounds like a plan.... 8)

[sweeteffx]

does "actual" fiberglass bond to metal good? I've heard that it shrinks and expands at a different rate than metal, causing cracks and such with temp change.

[kmfdmk]

You are correct. Don't be daft, one is a synthetic man-made material, the other is metal, of COURSE they're going to have two completely different expansion rates. However if you research it, and properly prepare the mating surfaces you should be alright.

Preparing them includes something along the lines of sanding it down to bare metal, and then using a coarse grit paper to somewhat "groove" the metal surface. You'll want to prime it of course to prevent rust/oxidization. Then follow the directions and lay down the fiberglass resin and glass itself. Make sure you use layers, and make sure that everythings properly mixed. Did I mention LAYERS?

Think of it like this a ship with an old style wooden plank hull is strong but very heavy. It does it's purpose but it's bulky and not extremely strong for its' size. Now look @ the yacht racing hulls who enter in races like the America's Cup etc. These have multiple layer hulls of extremely strong fibers & resins, fiberglass, and carbon fiber amonst them.

Many thin layers will almost ALWAYS give you superior performance/results as compared to a single thick layer.

Getting back to expansion rates. The pure fiberglass matting & bond-o-glass filler/fiber scoop should not have problems due to expansion rates, because it's on your ROOF, it's not like it's going to get the underside cooked to 3 or 400 degrees, and the top cooled from the outside wind, which is a scenario that fiberglass mounted on hoods experience. That's one reason that putting anything on a hood is hard to keep it from cracking, due to heat & vibration.

The roof flex may or may not crack the fiberglass mat & bond-o-glass roof scoop, but I seriously doubt that expansion rates will have much play when it's on the roof.