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-   -   Trying to make myself a fiberglass hood. (https://www.rx7club.com/1st-generation-specific-1979-1985-18/trying-make-myself-fiberglass-hood-935047/)

jgrewe 12-22-10 12:01 PM

Materials are cheap, time is the most expensive part. Hood itself, probably $35-50 depending on resin used.

My FC hoods use a foam core for most of the underside. I've played around with different ways to make raised areas to add strength. I've finally just doubled and tripled up with strips of the foam core in certain areas that would tend to lift from underhood pressure above 130mph. Those hoods weigh about 11-13 lbs and there is a lot of extra sqft compared to an FB.

The biggest trick with the foam is to taper the edges so they don't hold air during lay up.

MountainScreamer 12-22-10 12:14 PM

Jgrewe, could you post a picture of the underside?
What kind of foam are you using?

nofords 12-22-10 12:27 PM


Originally Posted by RE-TurboFB (Post 10378481)
yeah I have been thinking about changing up the frame design to save weight.. My only fear is that the hood might be to flimsy.

I'm going to try some new ideas on the third hood. I'll do a detailed write up on the next one with lots of pictures. As soon as I get some cash for supplies.

My race car just has a perimeter of 1/4"sq. aluminum stock and hood pins and it holds up well at 140+mph down the track. I do not have any issues with it.

I would suggest disposing of the steel back and replacing it with something similar with bonded aluminum box channel for mounts and prop rod holes.

The only issue I have with mine is that the hood tends to be really flimsy in high winds while up working in the pits. if the wind comes from the rear of the car it tends to wobble around. Not so much from the front. I solved this issue by running double prop rods. you will notice that the car has provisions for one each side. Just bend a second prop rod mount tab from a 'J' to an 'L' and insert! :nod:

RE-TurboFB 12-22-10 02:24 PM


Originally Posted by nofords (Post 10379443)
I would suggest disposing of the steel back and replacing it with something similar with bonded aluminum box channel for mounts and prop rod holes.

The hoods I made use a fiberglass backing.

RE-TurboFB 12-22-10 02:38 PM

Resin: $36.50 a gallon
gelcoat: $41.95 a gallon
1.5 oz CSM fiberglass: $3.40 for a 50" x 1 yard peice
PVA # 10: $15.95 a gallon
wax: $10.95 for 16 oz's

prices just to get you guys a idea of what this stuff costs.. plus shipping costs me out the ass!

I'm guessing it costs me around $110 to make one PLUS all my time.
I'll keep track of what I use on the next one and find out what they really cost.

jgrewe 12-22-10 06:34 PM

1 Attachment(s)
Here is a shot of an FC hood.

Not to bust your balls RE but your time is worth good money but you only need about a quart of gelcoat(being wasteful) and 3 quarts of resin at the most. A gal of PVA is almost a lifetime supply and a tin of wax will last a loonnnnnggg time too.

The money is from all the prep time from mold making all the way to the trimming of the new part. Guys, if you haven't tried this stuff, I'll tell you its time consuming to do it right. A lot of times you won't know if you screwed up somewhere along the line until you pull the part out of the mold !

Where do you buy from? I have a great place in town that I know ships all over check out fgci.com (Fiberglass Coatings)

RE-TurboFB 12-22-10 07:42 PM


Originally Posted by jgrewe (Post 10380008)
Here is a shot of an FC hood.

Not to bust your balls RE but your time is worth good money but you only need about a quart of gelcoat(being wasteful) and 3 quarts of resin at the most. A gal of PVA is almost a lifetime supply and a tin of wax will last a loonnnnnggg time too.

The money is from all the prep time from mold making all the way to the trimming of the new part. Guys, if you haven't tried this stuff, I'll tell you its time consuming to do it right. A lot of times you won't know if you screwed up somewhere along the line until you pull the part out of the mold !

Where do you buy from? I have a great place in town that I know ships all over check out fgci.com (Fiberglass Coatings)

Yeah those prices where just to show you guys how much I pay for supplies..

I'm still on my first tin of wax. your right a gallon of PVA does last a long time.. I have had too learn how to do this stuff all by myself.. So there was a lot of trial and error( lots of wasted supplies) trying to figure out how to use the stuff.

I use around 24 OZ of gelcoat on a hood, and around 96 OZ of resin on a hood. I know I could be using less meterials since my hood does weigh 13.8 Lbs.

I get my supplies from UScomposites. They are on the east side and I'm on the west so I pay big time on shipping.

I have always wanted to talk to someone that does this kind of stuff. To find out how they do it, where they get there supplies etc....

Thanks for the info!

jgrewe 12-22-10 08:26 PM

The guy that taught me a lot had a company that built boats. That alone saved me a lot of time and money because he would tell me the problem I was on my way to having before it happened:icon_tup:

There was a lot of, "you might want to wait a little more..." and "I would get on that about now"

I've been thinking about trying some of the UV cured resins but I can only find them in Cali. They have a long shelf life and can be cured with lamps or just putting the part out in the sun for a few minutes. Best thing is they don't stink from the styrene.

Jhereg 12-22-10 08:36 PM

Work looks awesome, If I didn't already have a used mariah hood sitting to the side right now I'd really be interested in one. Maybe a fiberglass one using mariah style scoops? That would be really nice.

RE-TurboFB 12-22-10 09:45 PM

WOW! Thanks jgrewe! That site is awesome! So many options... Damn I wish I could find a supplier in the west side of the US..

It must be great to be able to just pick that stuff up from the store..

elmerxfudd 12-23-10 06:00 PM

this thread rocks, looking forward to the how too.

vmarx7@yahoo.com 12-24-10 07:53 AM


Originally Posted by Man_in_black49464 (Post 10377999)
And if the rx7 club nazi says you cant sell it on here then contact the people who want you to make it like me and ill spread the word and so will the other guys your doing us a favor with your skills and we would love to see the product!

add me to the list of contacts if/when produced
interested in the dash w/ 3 gauge pods & the t2 hood

RE-TurboFB 12-24-10 04:30 PM

Hey guys,
Thanks for all the good comments!
I make a living on fiberglass boat repair. So I never really plan on making and selling fiberglass for the FB as of right now. But if it would be doing you guys a favor I could make a couple more.. as long as the forum permits it.

I would let this one go out of my "privite stash" if anybody wants it.. PM me with a offer or to add yourself as a contact if I make some later. (as long as it's cool with the forum)

I will make a detailed write up with lots of pictures as soon as I make my next prototype hood.

Thanks guys! and thank you rx7club!

stofficer1226 04-27-11 11:34 PM

Any updates???


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