Lightweight Cabinet Materials - Plywood/Coosa Alternatives

[Littleredridinghood]

Hello!
We are beginning our Unimog camper build which has a composite box on the back. The composite box was our first foray into the world of composites and it now has me thinking about our cabinet construction. I can weld and was planning on welding together aluminum angle and skinning it with plywood. However now I'm considering just building the cabinets out of something other than wood altogether. I'm not a huge fan of 80/20. I find it bulky and don't want to pay the high $$ cost when I could just weld together some aluminum we have here at our shop. We've completed 3 other camper builds and up to this point most of my cabinets have been traditional 1/2" plywood construction. I came across Coosa Bluewater and thought it was perfect, but the price had me running.

I would love to do a cabinet construction like this:
however I just cant afford 0.5" Coosa at $330 a sheet. Does anyone know of any alternatives?
Whatever product I use needs to be paintable with a final look similar to plywood, not be too complicated to fasten together, lighter than plywood, structurally strong enough to hold our refrigerator, oven, stove, drawers etc., available in the US market, hold up to the stresses of overlanding/our articulating camper box, and I'd like to make overhead cabinets out of it as well to keep the weight down at the top of the box.

Products I've come across in my research:
Thermo-Lite Board (similar to Coosa in cost): https://www.spaceagesynthetics.com/thermo-lite-board-product-line
Starboard (still pretty heavy): https://www.kingplastic.com/products/king-starboard-st/
AZEK PVC panels: https://www.homedepot.com/p/AZEK-0-5-in-x-4-ft-x-8-ft-White-PVC-Sheet-ARS01248096/315583746
Carbon-Core Carbon Foam Reinforced Panel: https://www.carbon-core.com/products/carbonfoam-structural-foams/fiber-reinforced-panel/

Does anyone have any suggestions for alternatives to Coosa Bluewater? Or do I need to bite the bullet and just use Coosa?

 

[Victorian]

As a cabinetmaker by trade, I recommend marine plywood. It’s really not that heavy. You can get 4x8 sheets in many different decors/veneers. My favourite is black walnut. Very durable, stunning grain and not as UV sensitive as Cherry, Birch or Maple. It will allow you to use standard furniture hardware and at the end you will have an interior that looks cozy and not like a tool shed. Metal cabinet will also make your interior sound ’loud” . If you don’t have the skills or tools to make them out of wood, outsource them through a high end cabinet shop. It’s all pretty standard stuff till you get to the plumbing and electrical stuff.

 

[Littleredridinghood]

As a cabinetmaker by trade, I recommend marine plywood. It’s really not that heavy. You can get 4x8 sheets in many different decors/veneers. My favourite is black walnut. Very durable, stunning grain and not as UV sensitive as Cherry, Birch or Maple. It will allow you to use standard furniture hardware and at the end you will have an interior that looks cozy and not like a tool shed. Metal cabinet will also make your interior sound ’loud” . If you don’t have the skills or tools to make them out of wood, outsource them through a high end cabinet shop. It’s all pretty standard stuff till you get to the plumbing and electrical stuff.

Thanks for sharing your expertise! I was starting to wonder how much I would actually save in time/money/weight by going with one of these less common but lightweight materials. I will definitely spend more time in doing something I haven't done before. In the end it doesn't have to be featherlight - the Unimog can certainly handle a little weight. Possibly doing the internal skeleton method out of square pieces of wood and skinning with a 1/8" birch ply might be the way to go as well?

 

[g_m]

Recently purchased some Coosa. About 1/2 the weight of comparably thick plywood. Great if you need it but yeah cha ching $$$

 

[Terra]

Penn-Elcom has various panel options, composite and plywood. I have not used them. It seams that they are pretty durable. Maybe someone has some experience and can chime in.

3/8" Black FLight Panels Lightweight Polypropylene Board

3/8" Black FLight Panels ™ Lightweight Polypropylene Panel One Side Black with Haircell Texture / One Side Black with Circle Pattern Width: 62" Length: 91" Thickness: 3/8" - Low weight (up to 60%...

www.pennelcomonline.com

 

[highwest]

We used ThermoLite to replace some plywood bulkheads and and the floorboards in our sailboat and saved a few bucks over Coosa. It was also easier to get (2 sheet vs 5 sheet minimum), but I do not think it’s quite as durable as plywood. Cover with fiberglass in areas that need strength. Paint with exterior house paint. Laminate with linoleum. It all works well. Overall happy with the experience.

We used ABS sheets painted with bedliner to face 8020 framing as the furniture in our Flippac camper. Also very happy there, but again, I think it’s not quite as durable as plywood.

Form working on old boats, I hate wood in anything that has a remote possibility of getting wet, but dealing with exotic sheet goods can be a pain. I will strongly look into plywood for the next camper.

 

[Littleredridinghood]

Recently purchased some Coosa. About 1/2 the weight of comparably thick plywood. Great if you need it but yeah cha ching $$$

In a perfect world, Coosa would definitely be my choice but my wallet says otherwise haha

 

[Littleredridinghood]

You will NEVER beat Baltic Birch.... definitely the best PERIOD. ZERO voids.

I'm definitely the most comfortable working with plywood for building cabinets. So it will certainly save me time. Birch ply might be the way to go!

 

[Littleredridinghood]

Penn-Elcom has various panel options, composite and plywood. I have not used them. It seams that they are pretty durable. Maybe someone has some experience and can chime in.

3/8" Black FLight Panels Lightweight Polypropylene Board

3/8" Black FLight Panels ™ Lightweight Polypropylene Panel One Side Black with Haircell Texture / One Side Black with Circle Pattern Width: 62" Length: 91" Thickness: 3/8" - Low weight (up to 60%...

www.pennelcomonline.com

Haven't seen this one before, thanks for sharing!

 

[supdies]

I've been able to get this plywood brand called Garnica from my local shop. It's a multi-ply popular plywood. I think roughly 55 lbs for a 4x8 3/4" sheet compared to roughly 80 lbs for baltic birch. Not quite as sturdy as baltic birch, but I think good enough and a notable savings in terms of weight.

https://www.garnica.one/en-us/plywood-boards/range/efficiency/efficiency-poplar.html

 

[Littleredridinghood]

We used ThermoLite to replace some plywood bulkheads and and the floorboards in our sailboat and saved a few bucks over Coosa. It was also easier to get (2 sheet vs 5 sheet minimum), but I do not think it’s quite as durable as plywood. Cover with fiberglass in areas that need strength. Paint with exterior house paint. Laminate with linoleum. It all works well. Overall happy with the experience.

We used ABS sheets painted with bedliner to face 8020 framing as the furniture in our Flippac camper. Also very happy there, but again, I think it’s not quite as durable as plywood.

Form working on old boats, I hate wood in anything that has a remote possibility of getting wet, but dealing with exotic sheet goods can be a pain. I will strongly look into plywood for the next camper.

I appreciate you sharing your experience. The hassle of the newer products might not actually be worth it in the end! If you're considering going back to ply then it might be worth us to just stick with the old standard!

 

[Littleredridinghood]

I've been able to get this plywood brand called Garnica from my local shop. It's a multi-ply popular plywood. I think roughly 55 lbs for a 4x8 3/4" sheet compared to roughly 80 lbs for baltic birch. Not quite as sturdy as baltic birch, but I think good enough and a notable savings in terms of weight.

https://www.garnica.one/en-us/plywood-boards/range/efficiency/efficiency-poplar.html

This is very intriguing, thanks for sharing this! It looks like a shop near me carries this as well. After reading everyone's thoughts here I'm thinking plywood might be the way to go and finding a lightweight ply is ideal.

 

[Victorian]

This is very intriguing, thanks for sharing this! It looks like a shop near me carries this as well. After reading everyone's thoughts here I'm thinking plywood might be the way to go and finding a lightweight ply is ideal.

I have been experimenting with a lot of lightweight alternative sheet goods for cabinet construction. The problem with all of them is the density to retain screws and other hardware. Think about screws that need to hold drawer guides in place. Yes, you could use rivnuts but that requires extra precision , cost and detailed planing. If you need to adjust your design during the build, it can become a headache to use anything else than wood screws.

On a side note: Baltic birch is VERY hard to get after the issues with Russia started. The "new" baltic birch plywood is coming from China now. I went through a bunch of sheets lately and actually find it better in quality! They also come in 4x8 and 5x5 (impossible to handle)

 

[SDDiver5]

Do these composite box companies offer some type of composite cabinet option? Same build type and quality, but thinner. Gets put together the same way. From my un educated view, that would maybe seem to be lighter than wood and the way to go for a DIY build. Something easier than what the video is showing.

Is that even a thing?

 

[Victorian]

Do these composite box companies offer some type of composite cabinet option? Same build type and quality, but thinner. Gets put together the same way. From my un educated view, that would maybe seem to be lighter than wood and the way to go for a DIY build. Something easier than what the video is showing.

Is that even a thing?

As mentioned above. I have been playing with this for years. You can use foam core panels to create divider walls etc . I used cut offs from door and window cut outs to construct the base for a seating area. Honeycomb panels can be used to create wet room enclosures, bed platforms etc. I do not recommend them for cabinet construction for already mentioned reasons.