Dltreezan

iTrader: (3)

hey guys finally finished that hood.....i will have pics coming soon of it......this is basically a write up of my experience with fiberglass and mold making......this is not a thread about the hood and when i get it done ill start a new thread about it.....this is strictly information i want to share with you from things i have learned from doing this myself, that way anyone in the future can use this as a reference for those of you that are interested in playing around and making things on your own. So this is strictly informative for those who want to read and learn and for those that want to add their own experiences or professional opinions. Now that the hood has been completed and two months in the making now i look back and think at all of the things that i learned now and where i could have saved myself and assload of time and money.....so basically i want to give a run down of simple ways of doing things and how it should be done now looking back compared to what i actually did. So lets look what i did compared to what i should have done now looking back that way if you guys in the future can save yourselves alot of time and money and hit that learning curve a lil smoother than i myself did.

Goal: Make a reverse cowl hood out of fiberglass....sounds simple enough

Step 1: Go to u-pull it off of foster and 112th in portland.....got a steel hood of a junk n/a for 25bux.......spend an hour figuring how the hell i was going to get it into my car......throw it into the hatch and leave the hatch open and drive all the way to wilsonville breathing my exhaust the whole time......spent 45 bux on a jigsaw to cut open the hole....took three days......steel is hell of a lot harder to cut than you think......

-what my dumbass should have done.....

made a mold of and copy my own hood....saved myself the trip...the 25 bux and the 50 plus on jigsaw and blades and i would have had a basic shape out of fiberglass that would have been a hell of alot easier to cut and build on and if i screwed up beyond repair i could always make another cheap skin off of my mold...and got the extra experience with the glass before making the final product itself....giving me more room to screw up........

Step 2: Make the shape..

what my dumbass did-

decided to buy the expensive polyeurethane foam that comes in two seperate containers.....pour it around the edges of the scoop and build up.....sand it and shape it accordingly and along with my measurements.....this took days.....went to the store....bought polyeurethane filler and coated the whole thing and filled in all of the rough spots....and sanded.......for about a week and half day and night......its more time consuming then it looks cuz u have to get EVERYTHING perfect and lined up.....and then to top it off ur doing it hunched over a hood that is sitting on a table.......then to top it off i decided to fix and sand the underside of the hood and fill in all of the supports and got it all smooth.......
why? dont ask because in the end we never took a mold of the underside and decided not to use it....so there goes a week and about 20bux of filler and sand paper......also......never ever ever ever assume something about the product that you are woking on......i had the shape down perfectly....and i stepped back and took a look....and one of the legs of the scoop wasnt in line with the windhsheild squirter but the other one was...but it looked perfect....and of course the windsheild squirters are going to be symmetrical on the hood right? so i must have messed up in all of my measurements...so i had to pretty much spend another day or two bondoing and sanding to get it to line up perfectly like the other.......and ****.....it was OFF....it was lined up the same....well i bust out the measuring tape like i should have in the first place and the damn squirters on the hood are not equal distance from the sides of the hood......SO i had to tear that leg back down and DO the **** all over again.....three more days......back to where it was....so dont assume anything and MEASURE everything......

-what my dumbass should have done

Built a lil shape out of a wireframe that was already perfectly measured down to the millimeter and that way i would have known it to be exactly on the spot......filled in the wireframe with the foam and sanded between the spots on the frame and made it symmetrically perfect as possible.....and used balsa wood to have made the frame and used templates and copied from side to side that way both would be exatly the same....like the fusealage on an RC plane......once i fixed the shape all i would have had to do was palce it on the fiberglass hood copy.....rather than have to work around a large steel hood bent over all the time....would have been much easier....and saved myself a bunch of eyeball time and depth measurement.......

Step 3: Make the mold

-what i did

got the mold release wax.....dont use car wax......and I was told id be save not using the pva mold release......so i used the wax and waxed the hell out of it....like maybe six layers of wax.......THEN i saw something i didnt like.....sanded it off and put a layer or two of wax back on it and went on my merry way of laying glass......put down my gel coat......then laid the veil mat....then two layers of 3/4 oz mat.......and thought i was done....i was using laminating resin from the plastic shop......and never used surfacing resin.......and thought i was cruising smooth.......once all was dry i went to pop the mold off of the master plug.....

what i should have done.....

i should have waxed it all the same......then used the PVA......use PVA......u basically lay it down one layer after another and let it dry between layers and what it basically is is a layer of liquid saran wrap after it dries...perfect barrier for mold release...pops the thing right out......also if you plan on making a strong mold to pop out many copies like 20 or 30 the mold will flex due to curing heat from the fiberglass.....so what you need is tooling gel and maybe a molding heat resistant resin if you want to be extra careful but it isnt necesarry

Step 4: pop the mold off of the master

My nightmare-

Well i had no PVA and my wax was thin in some spots.....so i spent about 3 hours popping it off of the mold whereas it should have taken maybe 2 minutes max......not only that but in some places the hood was stuck to the mold.....so when i pulled it off i just yanked it off and in many spots ended up ripping chunks from underneath the mold.....a freakin mess.........so for the next three days i spent time filling in all of the rips and tears and sanding them all flat.....well a hood isnt flat so it wasnt perfect....and my only option was to make a copy from the crappy mold and sand the excess off and work with a positive...much easier than fixing the mold....then make a perfect mold from the corrected product.......

Step 5: (Should be step 1): Make sure you have enough money to pour and calculate it as best as you can......and if you are unemployed and using your tax return i wouldnt try.....i obviously did.....and now im up against a wall......so when u calculate cost.....take ur estimate.....multiply it times pi......then divide it by the radius of your brain....and then youll know how much its really gonna cost.....i was thinking maybe 200 bux and a few weeks....its been a few months and about 600 bux.....the stuff also smells like ***.....so dont do it right next to your roomates window in a very small apaprtment complex with many neighbors....(I had to do it) - My roomates.....lol......So i ended up meeting some guy off of the forum with his own ideas.....and he wanted to throw some funds to finish it off and make a few more....so i ended up in a town with my cancerous hood staying with a stranger off of the forum to finish the thing......

Step 6: so we got started and laid down the wax.....the pva and then the gel coat on the inside of the mold...laid down a veil mat.......then a 3/4 mat.....then 2 layers of light typical weave cloth......then a layer of 2oz mat we got our hands on to......and before popping it out of the mold we cut strips of 8th inch aluminum and bent and laid it on top of the core mat (which acts as a barrier to keep things glassed it from pushing and shipping on the surface)....and then laminated the metal in with a light weave of cloth after sanding the metal surface to get it rough so it would stick.......

what OUR dubasses should have done- and plan to do next

do the same process with the gel coat and all......but use no mat.....mat makes it thicker and stronger yes....but not as strong as cloth and it soaks that expensive resin up like crazy......especially 2 oz mat.....we also found a very thick heavy weave cloth maybe 3/32 in thickness....very thick and strong and doesnt use any resin compared to the mat........so what we are going to do is to lay down a layer of veil.....cloth....put the metal in then the final and second layer of cloth...then another veil mat for a smooth underside.......also core mat whereever the metal happnes to be embedded......and ill tell you why...right now we have a prototype hood that looks great on the surface after about 2 weeks of wetsanding filling and wetsanding and perfecting to the best of our non-CNC eyeballs.......but the hood now used up nearly 3 cans of 25 dollar resin=75 bux......and was heavy because of it....also laying in the aluminum early on keeps the underside from looking all bulgy and shitty like it looks now because we stuck it on last....plus mat on the last layer looks like ***.....but i dont really feel like spending another week getting it perfect and sanding, plus the guy who bought it knows hes the ginuea pig and is expecting the first off.........so the mistakes not to make.....now one huge on that nearly wrecked the prototype......NEVER EVER mix different brands of resin.....some are slow cure and some are faster cure.....well we didnt know that.....so about three days after popping the hood out of the mold these bubbles started popping up in the middle of the hood causing us to have to cut the bubbles out and fill them in with resin and glass and then fill the surface....a mess....
well they havent shown up since.....also another thing.....when ur laying the glass use only about 2 percent MEKP catalyst......cuz u use too much and its nice and warm outside and u have 20 bux worth of resin in a bucket ready to go onto the glass and it starts gelling up its a waste.....throw it away and dont try to use it.......dont make that mistake....cuz we use the method of putting the glass down.........dumping the resin on top and using rollers and squeegees to get the air out and spread the resin............well if its gelled up on top the resin wont be able to soak thru....also airbubbles are going to happen....im not talking about large ones ...just the needle hole ones....and if for any reason you have to sand an layer of be prepared to fill them in.....also.....the glass itches like hell.....so when u are trying to get it out....use hot water and wash away from the pores....also wear a mask.....u dont want to be breathing the stuff.........

now we have the hood completed...the surface looks fine and as far as shape goes im satisfied.......and anything minor the body guy will fix with the primier when he primers and preps it then paints it so im not worried. But its heavier than they will be....so im expecting at least 20- 25 pounds....its right up there with the aluminum......maybe even heavier......and the underside is fugly compared to what they will be.....but its the first off......and we have a new mold off of it.......but every copy after this will be a HELL of alot lighter and we are shooting for perfection on the underside if possible....so estimated time to make a copy is a day max......maybe even hours......and expected weight is around 15 pounds...if i get rid of a few to offset my time and cost ill make a few other things for fun and see where it takes me now i have learned all of this....so i just wanted to share this info and my experience.....so if there are any questions.....go ahead and ask.....no questions for pics...ill be posting another thread about it....this is strictly for information for those to read who want to know how to do this and for people to add......just another thing to go down into the archive if possible.....

evileagle

iTrader: (1)

The ONLY friggin U-Pullit around here with FCs, did you get the hood off the red one or the gold one?

I got the bumper off that red one

- Ryan

Mr. Gadget

I feel your pain man!

astrochild7

iTrader: (3)

lol the gold one

88IntegraLS

Pain is right. Making original parts from fiberglass is an excercise in patience and self-control. It seems like it takes forever to get a smooth shape!

Bitchn7

I am abgout to take delivery of my own S4 RX-7 with the sole intention of using it to make a wide body kit for it.
With the bonnet I think tghe easiest way to go is find something the shape of the vents you want and graft them to the bonnet rather than make you own, or modifiy something that is close to what you want.
For instance, find someone who make motorcycle fairings, some of the jap bikes have awesome looking vents that could be used, or other vented bonnets, just the other day one of my body kit suppliers gave me a vnt they had cut out of another bonnet, it is made for the left side of a bonet (its not symetricle) so I will modify it so it is symetricle then copy it so I have two to use. I will use these in my bonnet and eventualy take molds from this. These will be on either side of the factory boonet scoop which will have the opening removeable insert replaced with a reverse opening vent I will make (these I can then also sell seperately to those who don't want the exspense of a complete bonnet).

I am currently in the stage of fixing an R-Magic S6 RX-7 front to take a mold from then will modifiy it to my own designbefore taking another mold, Its turning out to be a fun (hmmm not so good choice of words) and learning experience as you know doubt have found out.

Good on ya for doing something yourslef, the exact reason I am doing this.

Dltreezan

iTrader: (3)

wow sounds great...i wish i had taken pictures but i didnt want to post pics of my screwups...lol.....anyhow im hapy im done and cant wait to make a few more.....i really wish i had a totally finished product the way i wanted it...being lighter and all and looking good on the underside and i want one for myself right now but i cant afford it......so its had its triumphs and dissapointments.....and i wish to hell i made a bumper instead of a hood...and a full on kit is my next project if i get rid of a few hoods to offset my cost........88integrals....please take a pic with the hood closed all the way....i have been dying for months to see your car 100 together.....now its 99.99999 and im itching lool for that last lil bit so i can fel some closure....loool....but keep it up with the suggestions and information....its great

Dltreezan

iTrader: (3)

and yes.....fun can be a few words...and when you are broke and you want to get rid of one or two so you can enjoy it without ur back against the wall it becomes stressful.....and about making a mold of something symetrical and placing it on there i like the idea.....but i really wanted something of my own design....my own hands........now i know better if i had to do it all over again...thats why i wanted to share

Icemark

off to interior/exterior