Can someone tell me the diffrence between styrene monomer and sanding/surface agent? thanks. corb.
Styrene is basically used as a thinner for polyester resin.Surfacing agent or Wax Sol is styrene with wax added.The wax gives laminating resin a sandable surface. R. Brucker
While we’re on the subject… Why the styrene in S.A.? Is it neccessary to keep the wax soluable? Seems to me you want your Sanded Hotcoat as thick as possible…
To quote George Orbelian in his book ESSENTIAL SURFING: "Styrene- A water-thin liquid hydrocarbon monomer which is the primary ingredient of polyester resin. Also can be used as a thinner of polyester resin, to a limited extent. Surfacing Agent-Material added to polyester resin or used in association with it to prevent air from reaching the surface of polyester resin so the resin can cure. Surfacing agent is commonly paraffin wax in a solution.
…? I understand all that, and I know when to use each, I was curious what the Styrene is doing in S.A. It’s allready in Lam resin, and I would think that you want your Surface resin as thick as possible - nice smooth surface that covers underlying bumps…
I’m pretty sure that all that styrene makes the resin flow better. so that you get a smooth, thin, level coat as opposed to a thick, gloopy (technical term, yea) coat. It also evaporates out of the resin, leaving the wax film on top which allows the resin to cure to a sand-able finish. That’s my understanding of it… FWIW.
You wouldn’t want it ‘gloopy’, but thick? I’ve noticed that my Sanding resin seems a little thinner than Lam, not much, but a little. Gloss coat is very thin, and you’ll notice (if your like me, and you’ve left a less than perfectly sanded board) that gloss coat shows every little bump under the surface. I started kicking my hotcoat extra hot (hmmm… hence the name Hotcoat) so that it wouldn’t level out and show the bumps underneath.
I don’t think thick is the answer - you really only want it to fill the cloth weave, not fill wrinkles, & bumps that should not be in the lam anyway - those should be sanded out. And… the sanding resin should be a bit thinner (like you’ve noticed) since it has more styrene in it. …until folks like you, and me, get better at doing a smooth lamination, and better at sanding out all the bumps before gloss… we will see them in the board when finished. You just don’t find those bumps in the professionally laminated boards. Those guys (many of them anyway) are artists. Having stripped the glass off of a few professionally glassed boards I’m always amazed that the consistency of the glass job - it’s often more visible from the inside. No messy lap line, no lumps in the nose and tail, or on the curvey bits. No floats, no cloth/weave looks pulled or out of line. Perfectly even thickness’s. Just soo clean. Something (for me) to aspire too…
Howzit Rook, for some repairs I like my sanding resin to be a little thicker, so here’s how I thicken it. These days I use U.V resin, so I’ll have a container (small) that I pour some resin with S.A. into and let it sit out, but not exposed to UV rays. After a day or two some of the styrene will evaporate and the resin gets thicker. If it’s to thick just add more resin til it’s the consistency you want. In fact I have a batch in the works as I write this since I’m doing some repairs on a friends board. One thing though it will get to thick after to long and will probably get tossed so don’t make more then you need or it’s just a waste. Aloha, Kokua