what do you use to seal wood molds?

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#1

As one of my first projects I am planning to do a FB floorboard for my car(pic below). I plan to use the wood floorboard as a male mold. Is this right? or should I build a female mold?

For any case what should I use to seal the wood to avoid the gelcoat sticking to it?

I don’t want to do an overlay, since this is going to be just practice to build a CF one in the future?

Thanks for the help

#2

Sorry, I forgot to mention that I am planning to delete the top part. The New one should look like this one. Thanks again

#3

Polyerster resin would be the best but just about any spray paint that is fully dried before waxing and gel coat will seal wood.

#4

Thanks for your reply.
Any recommendations on what would be the best way to build the mold for this part?

Thanks

#5

looking at the pic…Id glue it to another flat board and clay around the edges. (after you have sealed it of course.

Then build a female mold from that form and let it cure. Make cutting templates from your original (this is super easy as its flat) and lay your cloth in your mold in wet layup or infuse. If you infuse youll need multiple entry and exit points…or you will get dry spots.

#6

Does the final part have to have that little inset piece? Is it completely flat?

If it doesn’t need that little inset, I would get a flat peice of mild steel, lay the part on it- finished side against the metal, wetsand and polish it if need be, lay the part on it, trace with a scratch awl (or any other sharp pointed piece of metal), and treat it with a mold release. Use your faviorite technique for the carbon/ fiberglass process, trim it out and you’re done.

I’ve done this with all of my flat pieces and they come out perfect. So much easier than making a mold!!!

#7

Hi DannyHokin,

Sorry but you lost me. I am not sure I understand the process that you mentioned.

Do you mean to make a replica part on sheet metal and cover it with FB?:confused:

Could you please describe the process like if you were talking to an idiot (any resemblance with reality is pure coincidence):smiley:

Thanks

#8

If that part it flat, just use a flat plate of steel/ alum or whatever, wax it many times with a mold release wax (carnuba), let it air out, buff again, mix and brush a layer of resin, let it “B” stage, mix more resin and lay down Fiberglass (FG…not FB) and work the air bubbles out. Cut many of the same pattern of FG pices but from different angles and continue on laying them up to the thickness you wanted.

Let it fully cure.

Pop it off the flat plate and then use you master to over lay it onto the FG panel to draw out the needed cut out areas, sand and finish it.

#9

OK, thanks. Now I got it.

Question, what do you use to make clean cut on FG or CF. A reciprocating saw?

I will probably try both, doing the mold and this other method, since the only objective with this piece is to practice.

Thanks again for all your inputs.

#10

Waterjet cutter…

or for the rest of us poor folk…a carbide blad of some sort. I have one for a “dremel” and one for a reciprocating saw.

#11

Whatever you use (we use a med. size bandsaw with the blade reversed & a profile router) try reversing or inverting the blade backwards…