View Full Version : How to make a fiberglass hood straight


cody
Mar 6th, 07, 10:52 PM
Learned the hardway that no matter how great it sounds, or how much money you spend ALL fiberglass hoods are junk(well at least %95 of them are. This is a custom made 3" cowl hood/bolt on from VFN. Took a lot of blocking and a lot of coats of filler to get it where it is.

http://img75.imageshack.us/img75/8050/img0721rh8.jpg (http://imageshack.us)

madmax87
Mar 7th, 07, 03:07 AM
Thats what has my leary about getting the Stinger hood. I seen them on a few cars but never really heard about the problems getting them to fit properly.

cody
Mar 7th, 07, 05:18 PM
Its not about the fit, but more so about the straightness or waviness of the hood.

Mark SC&C
Mar 8th, 07, 10:46 AM
We found great product for doing parts and panels like that. It`s a spray filler/etching primer called Rust Defender.
(get it,rusty fender :noway: ). There are other brands but this is the only one I`ve used. 3 coats layed on heavy will fill deep 40grit scratches and it sands really nice. We usually do one layer of regular filler where the big low spots are,block out with 40grit on a long board,hit it with 3 coats of spray filler,block it with 80grit,hit it with 3 more coats and block it with 180 then do 2 or 3 final coats with it thinned a little more then do the final block sanding. We were really skeptical but it saves a LOT of time and does a really nice job. The only downside is it runs about $100 gal. and you go through quite a bit when you mix it thick and lay it on heavy. Mark SC&C

cody
Mar 8th, 07, 10:53 AM
That sounds good. We did about 3 coats of filler and then a final coat with Evercoat Easy sand which is a polyester putty. We are going to do the entire car in Polyester Primer(filler primer) which we will spray on really really thick, like 4 coats at once. Then block that off and then finish with a urethane primer. Should come out really straight. This hood was wavy as ****

jet_car2000
Mar 8th, 07, 11:32 AM
Dennis you might want to look at the new stinger hood Ricks has now,,seen them and plan on getting one in the near future,,Frank

Everett#2390
Mar 8th, 07, 12:18 PM
Strange, my Unlimited Products cowl hood is straight, had it for 12 years now.

It all depends upon the model used to make the mold.

madmax87
Mar 8th, 07, 02:12 PM
Dennis you might want to look at the new stinger hood Ricks has now,,seen them and plan on getting one in the near future,,Frank

I'll do that. Thanks!

camcojb
Mar 8th, 07, 02:38 PM
Strange, my Unlimited Products cowl hood is straight, had it for 12 years now.

It all depends upon the model used to make the mold.

you have no idea how strange that really is! :D

Jody

BBCamaro
Mar 9th, 07, 12:17 PM
etch primer is in no way meant for filling scratches, if it fights rust it does not fill, and if it does it will shrink down into the scratches after a few months.
polyester primer is for doing ultra ultra straight paint jobs and or vettes and fiberglass parts, its name in the tech manual is "sprayable filler"

cody
Mar 9th, 07, 12:19 PM
etch primer is in no way meant for filling scratches, if it fights rust it does not fill, and if it does it will shrink down into the scratches after a few months.
polyester primer is for doing ultra ultra straight paint jobs and or vettes and fiberglass parts, its name in the tech manual is "sprayable filler"
To add to this, IIRC etching primer and filler do not go together right? Since the etch is acidic or something like that

cody
Mar 9th, 07, 12:22 PM
Strange, my Unlimited Products cowl hood is straight, had it for 12 years now.

It all depends upon the model used to make the mold.

BTW unlimited is known to make the worst fiberglass products on the face of the earth, but after this VFN I'm not sure if anyones is really much better than another

edd Gordon
Mar 9th, 07, 01:59 PM
I watched an episode on Dream Car Garage on how to make a fiberglass hood-- They laid it all out in a mold then vacuumed it and if You watched the show You could tell how much better they built that hood then a regular fiberglass production shop could make them. I watched the guys at Ecklers Corvette make fiberglass hoods and they didn't do it like Dream Car Garage did and You can see the difference in the final results.

Steptoe
Mar 10th, 07, 03:08 PM
I used to own a fibreglass manufacturing company...we produced everything from repro fenders, bus body panels, Foden and Mac truck panels, boat, caravans beach buggies to commercail air conditioning ducts.
The quality of the product depends on several things
1/the quailty of the orginal plug
2/The stiffness of the moulds
3/The skill on the guys on the chopper gun and the guys rolling out
4/ How the units are braced in the moulds before release
5/how fast the units are popped out of the moulds
6/Moulds do wrarp over time...we used to get 60 to 150 units from a mould, depending on the accrucy the customer required...some units like horse float roofs that could not be seen on top did not require the same finish.

The main issue with fiberglass is manufacturers pushing limits beyond the real lifetime of the moulds....making quality plugs/moulds is time comsuming and expensive.
Hence maybe the reason of comments above...re a unit obtained yrs ago and a recent on.
Fixing a warped unit....this can be done, but requires a lot of work...usually involving cutting and reshaping before even looking at any high and low areas.
Most of these can be 'pulled' out during the reshaping..