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Grp fibreglass deck



Has anyone made a fibreglass deck with integrated battery/electronics tray?
I was toying with the idea of building a mould and seeing if it would work…


I have never done one that is fully fiberglass, but did do one that is a combination of baltic birch and fiberglass. Basically, I made a deck using baltic birch and then routed it into different compartments. Then I apply a couple layer of fiberglass at the bottom of the deck.


How are u planning to make the mold? What would the board core be? I want to do this as well. If I had one competed board in the shape I want, make hard silicone mold with mother mold to give the mold structure, fill with expanding hard light polyurethane and carbon and vacuum bag. That’s my plan. The first board though to make the mold…was thinking 3D prints glued. Wood is too hard to work with for me without tools or press.

Might as well use carbon not fiberglass. Not much more expensive and much stronger so lighter


I was thinking of making a wooden plug and covering in a primer, polishing it up then making a mould from that. (like making a mould for boat parts?) I hadn’t originally thought of using any sort of core but could use a honeycomb core if the shape didn’t provide enough strength. I would have thought that an integrated box would make it stiff with a kind of Ibeam effect?
I use a fair bit of grp at work so it is not going to break the bank!


Check out OKP in endless he and whitepony have some great write ups on just these sort of things


What’s the distinction between fiberglass and grp?

What was going to be in the center of the board or hollow? If u had a honeycomb core In the board shape u wouldn’t need a mold and u could cover it with glass or carbon. But that would be harder and messy on the edges and everytime you’d have to cut a new honeycomb shape. If u make the plug the easiest best way to make a mold for me is to sink half the board under clay or wax or even in a warm coconut oil bath, when the board is half covered paint the exposed half and goop it on as it starts to set. (Aa a couple divots for matching with the other half) . flip it and take all the clay or oil off. Cover in Vaseline. paint and then goop on silicone on the other side… And the mold Is done unless ur adding a layer of fiberglass as a mother mold for structure.

.Because there’s a large overhand with the top clamshell half it would need to be connected to an outer mother mold and not just having placement divots for the molds alignment and alignment in the mother mold. Connecting silicone to anything but silicone doesn’t work and to give it enough structure I think it’d be easiest to do a harder duro rubber, which takes a day to set, and add some structural beams to this top half of the mold during the painting and goop job. Somehow. Make simply strips of pliable but stiff enough metal. Or even a lot of sticks.
Thinking and writing through the steps I’ve almost got it poured…in my head.

I’m sure there’s a good light strong polyurethane foam core that could be made in this mold.

Then a traditional carbon and resin wrap up and vacuum bag

The resins the most expensive part. Might as well spring foe the carbon, it’s so much lighter thinner and less weight ultimately for the same strength

If someone has a plug/pattern/ deck that we can both agree on the shape I’ll do the mold and make u a carbon covered foam core board. I want it to be intended for a lot of 18650 that are potted in long strips with a mold I made for them, and glued to the bottom. No lid. And another shallower spot for parallel vescs that would be potted in a much harder resin and and glued in place.

If any of u have Good 3D design ability and can make a design I’ll get it printed, glue The the 4 or 5 prints together, and prep it for a mold and make the mold and pour it and carbon it. Easier and cheaper Maybe if u have a deck that’s a nice shape and u have good hands on a router


Someone on here builds decks like this but I can’t think of the name…:grinning:


I made this out of fiberglass-


Please tell me if you remember :sweat_smile: I have a foam core that I want to have made, but I don’t really have the space or equipment to build it myself.


Grp and fibreglass I see as the same thing. I just put it on the topic in case people were using one or the other to search. I’ll let you know how i get on.
One very good core material is nidaplast. Very light and very strong. Used for decks of boats now in grp construction instead of using ply.



Have u used nidaplast? I see its an 8mm thick polyester fabric. How pliable is it before u add resin?

making a mold is a big deal but getting a little of this or another fabric-like material and using it to copy the curve of another board and then cut out the shape is easy.

I don’t know what to use as inserts for the trucks to bolt to.


Nidaplast comes in many different thicknesses. it does take a curve well before glassing, you have to glass both sides. If i was using it I’d be tempted to use some ply wood blocks to bolt straight at the point where the trucks were.
I’ve used Nidaplast but not in this application. (Boat building)


GRP = Glass reinforced plastic/polyester - aka glass and resin - aka Fibreglass.

Having been involved in building a boat with a PVC foam core (Divinycell) hull, the PVC foam sandwich construction process is no different in theory to a fibreglass reinforced plywood boat to that of a skate/longboard deck.

In both cases PVC foam is used as a structural element between two skins of carbon or glassfibre (with at least one skin on each side) encased in a cured resin, this is no different to existing carbon or glassfibre decks. The foam assists in establishing a rigid form in concert with the properties of the fibre, however in boat building multiple layers of PVC (held with epoxy glues) and reinforcements are often added where greater loads are expected, such as when planning to attach an engine on the stern of the boat.

PVC foam is generally lighter sandwich material per volume than plywood, having consistent physical properties, such as flexibility, heat resistance, being easily sanded, and not absorbing water. Plus, you can cut it with a pen knife! Another fun thing about PVC foam is you can thermoform curves into some types of foam with a heat gun if you need to. This comes in handy if you want to get creative fabricating curved structural or decorative elements, perhaps around a battery enclosure.

If I were you I would consider recessing wooden, or aluminium plates (which will not flex or compress) into the foam to act as a solid mounts to bolt your trucks onto.

While building a hull for a fibreglass boat requires a higher degree of planning than a skateboard to make sure it is structurally sound, the tools are generally the same. Depending on your weight, you might get away with a 20mm thick sheet of foam for a deck with two sheets of fibreglass on each side. You could probably do one sheet each side, but I like to double up for peace of mind.

You might also put multiple thinner layers of PVC foam together, with a sheet of fibreglass between each, that would also provide greater structural rigidity.

This is a link which shows how simple working with PVC foam as a structural element can be:


Ive been slowly setting up to make a carbon deck with divinycell using a vacuum infusion. Ever since I saw the hydroflex video years ago I’ve been into this idea and then mastercho showed he did one.

I’ve got the mold done which really seems to be the hard part and I have cut the different thicknesses of divinycell80 to the right shape. I plan to thermoform it with hot water at 212f based on its 80 something density and thickness today. I’m pretty sure since it’s closed cell foam it’ll be fine to get wet although I often see people thermoforming with it sealed in a plastic bag (?). Although I haven’t finished yet I’m about 1000$ into this with getting the “tooling” and the foam, resin, and carbon and tons of hours learning how not to do it.

My goal is to do as little sanding as possible and try to make it poop out of the mold done with no cutting or sanding necessary so all the edges will be wrapped with carbon. This seems the most questionable part as I mostly see people lay fabric beyond the foam and then they cut the shape out after it comes out of the mold

I think today is the day I throw it all in and run the resin through!

the mold took a while and that’s ok but its a big time consumer cutting the foam to the right shape. I’ve tried many different ways with an eye for accuracy and speed. I’m using a simple pattern using pattern paper now and simply a razor blade and it works but takes a lot of time. I’m excited to make a cookie cutter for the job some day and then…and then…I think I could poop them out quick and I’d like to try to sell them to YOU with a single long hubmotor!
I’ve copied the bustin sportster shape and it is a drop thru with a forked end so a bit more challenging maybe. If any of u have any advice or questions… I’ll hopefully put up a pic tomorrow

The real real goal is to have a board that holds all the cells with copper ended compression connections alone so that cells can be placed in and out easily. Maybe some day but at this point I’ll likely just solder my pack of (48) lg hg2 cells