Hello,
Getting lots of good info here, but have a question on my first mould.
I finished the plug, it’s an auto headliner, it’s been reinforced with resin and glass and filler, then coated with duratec and polished and waxed.
I’m making an epoxy mould (I wanted it to be durable and I just like working with epoxy) usng wet lay up.
I’m using epoxy “gelcoat” GPE for the surface of the mould, then glass cloth and low viscosity epoxy resin for the structure.
I should let the GPE gel first, then do the cloth layup, correct?
What thickness for the GPE and how light do I need to go on the first layer of cloth? Since I’m not using vaccum is print through a worry? I have 6 oz and 9oz cloth , do I need lighter than that? Most of the fiberglass veil I see is chopped mat I can’t use that in epoxy, right?
Ok, maybe this was too basic for this forum. I reviewed my books and decided I didn’t need veil or anything for making the mould.
I used the 6oz cloth and 9 oz cloth, used pieces that were cut to the size of the flanges and pieces cut to just the mold body, then pieces that overlapped both.
I started with white thickened epoxy , two coats, waited for gel before using the epoxy resin and glass. Took longer than expected for gel.
I used some woven roving and divinicell stringers to strengthen, but I’m a little rusty on my foam shaping since I haven’t done surfboards in 15 years! My stringers were too square and the 9oz didn’t drape well on the corners , so I prob have a few voids.
Here’s a pic of plug and mould, have to wait until I get back from thanksgiving to see how it seperates.
Plug, one pic at a time
Using an Ipad, huh? (images up-side-down)
Anyhow, my recommended method for epoxy moulds is to apply gelcoat, drape in glass cloth while it is still wet, then have it cure, then laminate further. The half-wetted cloth will Ensure a good bond. (nicest is a Verranne cloth, a needled cloth, or a twisted yard cloth)
Are you going to make epoxy parts, or polyester parts?
Herman, do you recommend making an epoxy mold, using only verranne cloth, or using it in contact with gel coat and the use other fabric? (like 200, 300, 400 gr fiberglass)
Yup, ipad.
I applied the epoxy resin and fiberglass when the gelcoat had just reached gel stage.
Are you recommending applying fabric to the gelcoat without additional resin to wet the fabric with the gelcoat layer?
I’m planning on making mostly epoxy parts, but possibly doing polyester for mold testing or making cheaper versions.
Epoxy tools do not like polyester products.
Yes, I mean laying cloth in the wet (not tacky, then you are too late) gelcoat, and do not impregnate it further. So the cloth is half-wetted.
Won’t the cloth print through, then?
And why don’t epoxy molds like polyester? Heat of reaction?