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I've been working on designing my build and have come to the conclusion that I'll probably be making my own nose cone. I've seen plenty made of fiberglass, but the build process seems wasteful and thus expensive. What I'm talking about is the buck > mold > part process that requires building 3 whole pieces out of fiberglass to get the final panel. What I'm thinking of doing is using foam and some fiberglass to create the buck then taking that and using it as the mold for Vacuum Forming. I think this could be the best solution, cheaper, lighter, and more durable, since I only need one mold, saving cost of fiberglass and resin, the plastic wouldn't need to be very thick and is pretty light, and many plastics are more flexible than fiberglass it's bend and not crack. So am I on to something or am I just dreaming?

Should be interesting. A nose cone is a pretty deep draw for a thermoformed part.

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OOPS I did it again
http://www.locostusa.com/forums/viewtopic.php?f=35&t=17496

Blood Sweat and Beers
http://www.locostusa.com/forums/viewtopic.php?f=35&t=15216

you do know you don't have to make a full blow mold to build fiberglass parts . molds are great if your going to make more then one but it's not a must .
often in my shop we will have just one part to build so we will just shape a big foam block to the shape needed and lay up over the top of the foam .
a polyester spray filler will fill the cloth weave with 3 to 4 coats it's just a supper high build primer . then we block sand and machine sand (DA) WITH 180 GRIT then prime again with a standard filler primer . from there we do our final sanding with 400 to 500 wet or 320 to 400 dry after that we wipe down the part with a pre paint cleaner , tack the part off and spray one medium wet coat of sealer then going wet on wet right to our top coats base clear or single stage .

the foam blocks for fiberglassing is dirt cheap and it's very ez to work with . a grinder with 36 to 24 grit will shape it quickly . hand sanding with 36 to 80 also works good .
we will some times use a mold release but more often we use good old clear packaging take as it too is very low cost and fiberglass will not stick to it at all .
because your doing a reverse lay up the back side of the part is what is laying over the mold .
you can vacuum bag the parts like this but doing a reverse lay up on a small nose piece there is no real need for it .
we tend to only vacuum bag large parts and all carbon parts we build .

the cost of making a part like this out of a plastic is more costly then just building it as a reverse lay up part .

What ^^he^^ said!
Build the shape you want out of foam insulation from Home Beepo or SLowe's, lay up several layers of fiberglass inside and out, fill as needed, sand and paint. Work in progress-- And Finished Product--Look here for more detailed instructions from Pook, who does some really good stuff with this method: http://locostusa.com/forums/viewtopic.php?f=23&t=8113

I have no experience with vacuum molding plastic, but this HAS to be easier (After all, I did it!) and cheaper (Same proof!)...

JDK

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JD, father of Quinn, Son of a... Build Log
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"Gonzo and friends: Last night must have been quite a night. Camelot moments, mechanical marvels, Rustoleum launches, flying squirrels, fru-fru tea cuppers, V8 envy, Ensure catch cans -- and it wasn't even a full moon." -- SeattleTom

you don't have to use the foam board as your core material .
what we use on a lot of builds is baltek core mat . it's extremely light weight .
most of the time all you need is one lay up of a 10oz cloth and then one lay up of a 1.5oz over the top of that on the out side and one 10oz lay up on the inside to get a very strong very light weight part .

we do not use the foam for part of the panel it's self we only use it for the shape the we pull the part off the foam .

with the 1.5 OZ cloth most of the time you can just use a spray filler to get a very smooth substrate to paint over .

the baltek core is great as it's takes very little resin to wet up and it's a very thin core material .
being thin if you have to run a bolt through it the material does not crush like a honeycomb or foam center core material does .

I use it for the fiberglass splitters we build .

There is a reason most fiberglass shops use the 3 stage method, it is reliable and cheap as well as a mold on hand for further pieces. If there was a better way after all these years don't you think they would do it?

But hey, I'm one of those guys who tries things for the hell of it and have a lot of fun learning good and bad, so I say go for it anyway for the experience.

Hi 962porsche. I greatly enjoy your posts, they are very informative.

Pardon my ignorance, but is the Baltek core mat you mention a balsa wood product, or foam or honeycomb, or ? I googled it and am unsure what product you are referencing. Is it a rigid board type material, or something else?

Jack

962porsche,

as picture tells a thousand words, could you take some pictures next time you do this on something a similar shape to a locost nose?

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thanks
it's kind of like a cloth/foam material .
I buy it in big rolls as we tend to use a crap load of it . we get it from fiberglass supply .com it comes in 2mm , 3mm and 4mm thickness .
if you google it I think fiberglass supply will come up click on the site and you can see what it looks like .

there are many ways to skin a cat !
the same applies to fiberglass work .
you can make molds if your building more then one or two parts but it's not a must .
there are also many ways to make forms to lay up parts .

if I was to just build one nose piece for the 7's I would 1st take a 3' X 3' x 3' block of 4LB density urethane foam .
shape and carve it to the shape it would need to be .
then because I may want to lay up more then one if the car ever needs it I would spray a coat of polyester spray fill over the foam .
then I would spray a coat or two of mold release over the spray filler .
I then would cut and size all the material core and cloth for the lay ups .
after that is done I would mix my polyester resin and wet up the 10oz cloth and lay it up over the mold .
so I would not have to sand between lay ups I would use the norox azox catalyst not the methyl ethyl ketone peroxide catalyst .
the difference between the two is one stays open for about 16 hours so you can do your next lay up before it cures totally hard as the faster catalysts do .
after it's flashed off for the next lay up you use the 1.5oz cloth .
the next day when it's cured pull the part off the mold and lay up the core material and another lay up of the 10oz cloth to the under side .
once that is finished and cured you then can sand the part with 80 grit do any plastic body filler it may need and then spray 3 coats of a polyester spray filler . most of the time spray filler is all you should have to do .
then sand the hole part again this time with 180 grit and spray 2 to 3 coats of a good old filler primer .
then sand that when dry and you can top coat with a color of your choice .
for race cars we will skip the spray filler as that is to only get rid of the cloth weave you would see after the part is top coated .

so to compensate for the core material being added inside the product would you make the plug larger by the thickness of the core material?

this is in regard to a nose piece having to fit over a frame of a specific size

_________________
this story shall the good man teach his son,
and chrispin chrispian shall ne'er go by,
from this day to the end of the world.
but we in it shall be remembered.

yes if need be you adjust the mold size .
or like I was saying about more then one way to skin a cat you can also start your lay ups from the inner part of the panel .
how ever when this is done you will at times not get a panel that is as smooth and flat as you will if you just lay up the two out side layers 1st .
on average a lay up of one 10oz and one of 1.5oz cloth is going to be around 1.40 MM total .
so take the say 2mm core and the 10oz of the inside build up and your going to have about 2.8mm total build up added on the inside of the panel .
so depending on just what panel your building you may or may not have to adjust for that .