Anybody know how to make stuff out of FRP?

[$100T2]

I have a few ideas for bumpers for my FB, but don't want to make them out of pure fiberglass. Anybody know how to make FRP??

[RXtacy]

I believe you have to mold FRP don't you? I can't see it being economical for a one off piece.

[$100T2]

Well I was planning on making a mold to make my pieces really nice anyway. I just want something with some give to it so it won't crack or split like fiberglass does.

[fikren]

to my knowledge its just a epoxy vinyl resin and fiberglass fibers rather than sheets with a heavier mix on the resin vs the fiberglass. The mix of the two varies depending on application and I think most peoples recipies (mix ratios)are not something they want published such as if you called up shine and said "hey whats your mix for your FRP" I doubt they would tell you. Or at least thats how I am percieving it.

There is an great company called Fiberglast.com who are very helpful with chosing the right products. You might give them a call and see what they recomment. I know other places like USComposits are usually cheaper price wise but the couple of times I called them the people I talked to were really rude like they didn't have time to talk to me about their products.

[fikren]

there are also several methods of laying up fpr the common ones are hand laying, spraying the resin glass mix and then a closed mold where the mold is filled with glass and pressure injected with the resin.

[warwickben]

i have a book that deal's with this stuff.
if you want to make the parts out of carbon fiber but dont mind havening to paint them it says you can hand lay them on a mold like you can with fiber glass.

ask some questions and ill try to find the answers in the book.

[fikren]

think hes after FRP which is fairly bendable when cured. Has some give to it so a slight tweek in the frame or hitting something with it won't crack it all up like fiberglass or carbonfiber will when layed in sheets.

Does the book mention anything on FRP such as resin to fiber stands mix ratio?

May have to do just a trial and error kind of thing mix up a small ammount, let it cure see if it has what your looking for as far as strength vs flex.

[fikren]

On a side note, you might pm jkl enginering here on the site, they may not give you an exact recipie but may be able to get you steered in the right direction.

[warwickben]

the book is made by hpbooks fiberglass and other composite materials.
theres way to much info for me to retype. id be retyping the whole book. its a great read tho.

[blwnrtr93]

I visited a local kit car company a couple years ago and got a tour of their facility. It looked like they were using just layered fiberglass sheets for their car bodys and panels. A combination of different weaves for strength. I think since you are making a mold that you'll be quite alright with just the fiberglass, although you may want to put some of the 3M clear tape over the part, once it's painted, to help reduce the chipping and cracking.
+1 on trying out your resin mix in smatch batches before you go all out. I've been using the really small (2 oz I think Dixie cups) filled 3/4 the way up with resin and then adding 14 drops of hardener from the small tubes and it's worked out pretty well. I use this mix with the fiber mat as well as fleece material when making speaker enclosures.

[warwickben]

what do you plan on making.

[fikren]

I have a few ideas for bumpers for my FB, but don't want to make them out of pure fiberglass. Anybody know how to make FRP??
:)

[warwickben]

i feel dumb. i was thinking of making a bumber for my sa since no one makes a bumper for my car . i just need to make a parts that goes from fender to fender.
my bro hit a rock and messed up the plastic grill and the 2 square panels.

[blwnrtr93]

There was a write-up in either Superstreet or Import Tuner when the G35 first made it's appearance where WingsWest was making a custom front bumper for it. I've sinced trashed the rags and held on to my invaluable resource materials (SCC and Modified).

[FIBREMAZ 13 BEEF]

Pretty sure that FRP requires the use of injection moulding (can be expensive to set up)

[therighthand]

Just wanna give a little more information from what I know which is not considerable.

The steps involved in creating a truly new bumper would require a significant investment. For the production of an OEM fitting quality bumper that could be used for making an unlimited number of bumpers this means CNCing a solid block as the mold. They create the CNC pattern from a CAD basis so they can play around with 1,000,000 designs before putting it into production. Obviously for anyone other than an OEM this is far too much investment. The only company I know doing something like this is Saleen.

Another form would be getting a CAD model cut into a large block of wood or specialty foam. The disadvantages of this are that the materials are affected by the heat generated through the chemical reaction of the resin and the composite.

Yet another way would be to sculp literally the shape you want by adding clay to your current peice and sculping it. Once your desired shape is there you could either make a mold by using special plastics intended for the job (look at Freeman Composites) or by using this created shape as your female then making a part on it. Then using the made part as your mold, basically make the part then on the inside filler sand and then primer and sand. Fiberglass doesn't sand well at all so doing this is the step to get a smooth and air bubble free surface. Once this is completed mold release wax the inside, spray Gel coat and lay up fiberglass.

Hope this helps give you some ideas,

Alex I.