Core material in Fiberglass layup

[SuperDrifter]

Coosa board, Coremat, Nomex honeycomb, closed cell foam- upper hull choices at sandwiching a core material?

 

[SuperDrifter]

Builder out there? I'm Consultant $ friendly

 

[Quinc]

keep searching through the forum. I believe some of this has been covered.

 

[SuperDrifter]

Core lamination . Yes, Quinc it was worth the rabbit hole of knowledge, i learnt a few things

 

[SuperDrifter]

Coremat or Foam seems the choice. So many variables.

 

[WFO Speedracer]

I have always wondered about using expanded PVC , it's thermoformable , it gules up with epoxy really well also , I use it a lot in repairs or when customizing a ski , especially like it for repairing bond rails or building a whole new bond rail like I did on the Superjet build .

 

[Storbeck]

I don't think honeycomb is typically used with wet layup because there is no good way to control the resin in the open honeycombs, you don't want them to fill with resin. Similar with Coremat. You want something that will bond well to whatever fiber/resin you're using, but not soak up resin.

I think.

I'm no expert, to be clear.

If I was looking for info like this, I would poke around searching about stuff like canoes, surf boards, model airplanes, ultralight/experimental airplanes. The airplane guys will probably have really good info. I'm guessing. You want a topic that requires good strength to weight, but also attracts a crowd that is methodical and nerdy. So airplanes lol. It will all be very old and possibly outdated but Burt Rutan was a guy that was very much into doing foam core airplane parts, could be worth searching for that.

I suspect you'll land on some sort of closed cell foam.

 

[SuperDrifter]

Yep, closed cell foam FTW

 

[WFO Speedracer]

I believe the idea behind the Coremat is it creates basically an I beam between the layers of glass , carbon or whatever.

The expanded PVC is basically very closed cell foam board , the shiny finish on it has to be sanded with at least 80 grit to create some tooth but I have repaired many things with it, I have never had one come back.

 

[SuperDrifter]

How to bond 2 glass sandwiched foam (1/8" or 3/8") panels, edge to angled edge?

Plexus or Cabisol lapped w/ glass?

 

[SuperDrifter]

thermoformable

interesting, raw material, prol a little heat and a fixed position

 

[kevbo]

In aviation they spend a LOT trying to save a little weight. One project I worked allowed $50K per pound of weight savings. Often outer skins are made under high pressure then they are grit blasted and have nomex bonded to them for stiffness. You may be able to do it all at once using foam on a jetski hull. Just make sure the outer layer is at least 3X thicker than the inner layer. Cored laminates are great but tend to be fragile when used on boats because its too easy to overload the structure. I think a waffle structure around the engine could save some weight but its not easy and costs would rise a lot. I think a solid laminate hull using surplus carbon a decent resin is the best we can hope for.

 

[WFO Speedracer]

I do know that XFT built some Nomex honeycomb carbon fiber skis , one has appeared here for sale several times since Charles sold it.

 

[Storbeck]

Another consideration is that core material is more helpful in a flat panel than one with compound curvature. Most of a ski hull has compound curvature. My dvx had core material along the gunnels in the engine bay and on the top of the hood, both areas that are relatively flat on a dvx.

 

[JC-SuperJet]

I believe the idea behind the Coremat is it creates basically an I beam between the layers of glass , carbon or whatever.

The expanded PVC is basically very closed cell foam board , the shiny finish on it has to be sanded with at least 80 grit to create some tooth but I have repaired many things with it, I have never had one come back.

Mister Ho does no such thing!

 

[WFO Speedracer]

Mister Ho uses Ramen noodles for a core !

 

[SuperDrifter]

Biax Ramen

 

[WFO Speedracer]

Biax shrimp Ramen , it's waterproof and submersible.

You can always use wire mesh like this guy lol.