how bout instead of laminating, using something pourable and castable?
like a casting epoxy or fine grade cement/concrete, or even polyurethane? you could probably coat it later with something to make it less crack resistant.
if you're not going for 1000 copies at 100 psi and 200+ degrees i dont see it being a problem
Ski profile (across the width)
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knightsofnii
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Yuki_otoko
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Concrete and other similar materials have low tensile strength. In construction the reinforcment bars transfer the tensile force to compression. Just like laminates or steel columns with two flanges seperated by a web. For example a suspended slab would just crack out for underneath and collapse without reo. The reo stops the bottom from stretching and falling out, then transfers the load to the top where the concrete is compressed.
That said, I would say it would be hard to reinforce the concrete from chipping off without making a huge mold. This would be to heavy to lift.
Wood would be just as strong as the lower mold used on presses, but then you need to seal it and line it up.
What about if the ski was laid upside down? The top would be below, and then the glass/core/glass is laid. Then the base is draped over the mold and vacumed down. You can then see to line it up (very important I would guess on a 3D shape, especially if using a capped construction)
It would then be possible then to take a sheet of base material (or cheaper equivalent) cut the shape of the base with edges out then use this in the style of a cassette. Place this over the mold to find where it lines up and drill a few holes for pegs or screws. Place a few o-rings between this sheet and the mold to space it to the same height as the layers of fibreglass that stick out the mold. It would need another sheet of base material over the top to hold it better in place and stop the epoxy from going everywhere. The countersunk srews could then go though both layers of the "cassette" and into the mold, being spaced by the o-rings to the correct height. Because the ski is being layed upside down, it might be possible to trap air bubbles if the "cassette". This could be solved to cut every small grooves/channels in between the two layers of the "cassette" directing air and a little epoxy away. All this sholud then make it possible to be pressed.
The mould could be made of wood, then remove a large amount for a channel from where the ski shape would be. Enough to then fill with something like knightsofnii mentioned to make the shape, then sealed and release coated.
Does this sound like it plausible? What sounds like its on the right track, and what sounds like it wont work?
That said, I would say it would be hard to reinforce the concrete from chipping off without making a huge mold. This would be to heavy to lift.
Wood would be just as strong as the lower mold used on presses, but then you need to seal it and line it up.
What about if the ski was laid upside down? The top would be below, and then the glass/core/glass is laid. Then the base is draped over the mold and vacumed down. You can then see to line it up (very important I would guess on a 3D shape, especially if using a capped construction)
It would then be possible then to take a sheet of base material (or cheaper equivalent) cut the shape of the base with edges out then use this in the style of a cassette. Place this over the mold to find where it lines up and drill a few holes for pegs or screws. Place a few o-rings between this sheet and the mold to space it to the same height as the layers of fibreglass that stick out the mold. It would need another sheet of base material over the top to hold it better in place and stop the epoxy from going everywhere. The countersunk srews could then go though both layers of the "cassette" and into the mold, being spaced by the o-rings to the correct height. Because the ski is being layed upside down, it might be possible to trap air bubbles if the "cassette". This could be solved to cut every small grooves/channels in between the two layers of the "cassette" directing air and a little epoxy away. All this sholud then make it possible to be pressed.
The mould could be made of wood, then remove a large amount for a channel from where the ski shape would be. Enough to then fill with something like knightsofnii mentioned to make the shape, then sealed and release coated.
Does this sound like it plausible? What sounds like its on the right track, and what sounds like it wont work?