Polyester resin: life & thinning with styrene

I had customers that built them for semi trailers and motor home side walls.

For RV's they used a mold (large flat table) that size, they ran on tracks around the building. There was a large chopper gun that moved back and forth as the mold moved under it. Once the glass was laid down it was lightly rolled then sheets of ply, mostly luan, were set in place. A vacuum bag was used over this to consolidate the glass and ensure full contact with the wood.

There was a strip of glass used on top at the seam to reinforce it. Resin was an ISO/DCPD blend.

We made 11 molds (tables), they were used for close to ten years being cycled a couple of times everyday. After the down turn in the economy the plant was closed, now several of the tables are still being used by other companies.

I have customers that still build semi trailer side walls, so I won't disclose exact methods, but it's a variation on the same theme.

 

The large molds are frequently made on a concrete floor that has been leveled with self Leveling products. Zero (low) shrink tooling resins and a core make up the laminate. Large beams are used for support with lots of bracing. Sometimes the the surface is reworked to get it even better. Then you try and keep the room at an even temperature so it doesn't move.

 

PREPARATION FOR COVERING WOOD WITH FIBERGLASS AND POLYESTER OR EPOXY

NOTE: If working with old wood, remove all paint and foreign material from surface.

Step 1: Sand surface with 60 or 80 grit samdpaper to rough-up surface.

Step 2: Brush or roll on a primer / saturation coat of catalyzed polyester resin thinned 25% with
acetone or styrene. Epoxy resin should be thinned 25% with 1271 Epoxy Solvent.

 

In slab radiant heating would work with that very well, I would think. Once set, turn up the heat for a good cure.

 

This was posted on another topic but also posted here, so I will erase it. Deleting it yesterday didn't work.