PVCX is heavier than plywood???

I had always thought one of the advantages of PVCX over wood was the light weight. I have found a source and was going to order, but looking at the technical data, it seems that it is MUCH heavier than plywood??? This doesn't seem to make sense.

You can see the weights of plywood here:
http://parr.com/PDFs/PG_plywoodthickness.pdf

And here is technical data for the PVCX Komatex and Komacel:
http://www.kommerlingusa.com/komatex/technical.cfml
http://www.kommerlingusa.com/komacel/technical.cfml

As you can see, a 4X8 foot sheet of 3/4" thick plywood is about 60.8 pounds

However, the same size and thickness of PVCX are 94 pounds and 76 pounds per 4X8 sheet for the two brands respectively? Same pattern for the other thicknesses.

I wanted something light weight, now I am quite confused. Does anyone know?

What are you using it for?

Before my ex wife ruined my company (grumble grumble :taz:) we used to manufacturer showcases and enclosures out of acrylic. It's very light.

Quote:

---

Originally Posted by Rickys_Reptiles

What are you using it for?

Before my ex wife ruined my company (grumble grumble :taz:) we used to manufacturer showcases and enclosures out of acrylic. It's very light.

---

You should start that up again at some point.

Can you get Forex sheets in the states? Its used here frequently its hard foam pvc supposedly really lightweight.

Quote:

---

Originally Posted by Rickys_Reptiles

What are you using it for?

Before my ex wife ruined my company (grumble grumble :taz:) we used to manufacturer showcases and enclosures out of acrylic. It's very light.

---

For making a snake rack. I am very very confused here, because I have been reading over and over "use PVCX, it's light weight. Melamine weighs a ton!". Then I found a supplier of PVCX and he can't answer my questions about whether it is hard enough for snake rack etc. The best he could do was let me visit their factory and inspect a sheet of their PVCX myself. They had Komatex and Komacel. I lifted the 4X8 foot sheets and they were heavier than I imagined, although not heavy. Obviously this isn't an indication of what a small sheet would weigh so I looked up the specs and it seems that plywood is MUCH lighter than PVCX!

To top it off, I had always thought when you guys talked about melamine that you meant plywood with the melamine coating on top, which is what I am using in my old racks. Thus, I thought PVCX would be a lightweight alternative (turns out it is even heavier?). Then a member here who has been trying to help, messaged me telling me not to use melamine because of many problems, but at the end one alternative he suggests melamine on plywood?? So "don't use melamine, use melamine on plywood instead"?

What exactly do you guys mean when you talk about "melamine"? Is it plywood or wood of some kind coated in a "melamine" cover? Or do you mean sheets of PURE melamine, which I didn't even know existed?

I feel like I'm tripping on acid. I think I am losing it.

Quote:

---

Originally Posted by hungba

For making a snake rack. I am very very confused here, because I have been reading over and over "use PVCX, it's light weight. Melamine weighs a ton!". Then I found a supplier of PVCX and he can't answer my questions about whether it is hard enough for snake rack etc. The best he could do was let me visit their factory and inspect a sheet of their PVCX myself. They had Komatex and Komacel. I lifted the 4X8 foot sheets and they were heavier than I imagined, although not heavy. Obviously this isn't an indication of what a small sheet would weigh so I looked up the specs and it seems that plywood is MUCH lighter than PVCX!

To top it off, I had always thought when you guys talked about melamine that you meant plywood with the melamine coating on top, which is what I am using in my old racks. Thus, I thought PVCX would be a lightweight alternative (turns out it is even heavier?). Then a member here who has been trying to help, messaged me telling me not to use melamine because of many problems, but at the end one alternative he suggests melamine on plywood?? So "don't use melamine, use melamine on plywood instead"?

What exactly do you guys mean when you talk about "melamine"? Is it plywood or wood of some kind coated in a "melamine" cover? Or do you mean sheets of PURE melamine, which I didn't even know existed?

I feel like I'm tripping on acid. I think I am losing it.

---

Melamine sheets are traditionally chip board rather than plywood. He is likely suggesting you buy plywood and use the melamine wrap to finish the plywood.

Quote:

---

Originally Posted by TJ_Burton

Melamine sheets are traditionally chip board rather than plywood. He is likely suggesting you buy plywood and use the melamine wrap to finish the plywood.

---

Well perhaps this is where the confusion was from. I do not live in the USA and the "Melamine" we have available here are ALL plywood coated with the melamine wrap. I have not seen the chip board version at all except in imported furniture, but never sold as material here. They have chipboard, they have plywood coated in melamine wrap, but not chipboard in melamine wrap.

So, the "toxicity" from "melamine" is from the glues in the CHIPBOARD, and not directly from the "melamine" wrap? I thought it was the melamine wrap that was outgassing formaldehyde.

Also, when comparing weights, you guys mean the Chipboard coated with melamine is too heavy, hence use of PVCX? I presume the chipboard coated with melamine is a lot heavier than PLYWOOD coated with melamine? Because from the technical data is seems that PLYWOOD is even lighter than PVCX. If this is true there is no reason for me to pay for PVCX as it is 4 times the price of plywood covered in melamine here, and the latter is available across the street from where I live. I wanted something lighter and before I saw it I was expecting PVCX to be really like like styrofoam or something.

Also, i think people usually only use 1/2" pvc as it won't sag like thinner melamine can. That would probly be where the weight savings comes from. just an educated guess though as I have not worked with pvc before.

Well, I was planning to make the rack two 32 qt tubs across, and 13 levels high. People keep telling me that "melamine" would sag at 1/2", but my "melamine" (plywood) of 1/2" does not seem nearly as bendy. Do you think if my shelves are two tubs across (31 to 33" across or so for each shelf) that PLYWOOD covered in melamine (not the particle board) at 1/2" would suffice and not sag?

I would presume that plywood is a lot stronger than particle board?

I would think as long as you use the 3/4" ply you should be fine. Ply is a lot less likely to sag in my experience, and definately weighs less than the particle board at the same thickness. I wouldn't mind finding some melamine coated ply here, but i haven't seen it before.

Is 3/4 ply really necessary? I have one rack made of that and to me it seems like overkill. Admittedly those racks are all 1 tub across, but just feeling the 3/4 plywood it feels so stiff I don't really think that it is necessary?

Is the melamine laminate itself toxic or the particle board and the related glues that are?

I've built abut 20 racks in the past year, consisting of at least 5 different designs. Here's some thoughts I have about some of your points/concerns.

Firstly, melamine is a wood based product that is thermally fused to melamine resin, which makes a strong and waterproof material. It is HEAVY. It also will not warp over time like you would see in almost any kind of plywood product. Warping is associated with fluctuations in humidity within the wood structure over time. This is often exacerbated by the natural grains and imperfections within the natural wood structure found in plywood. Bottom line: Melamine is heavy as hell, but is also waterproof and will be more resistant to warping. Its not toxic to snakes either. I think if you used plywood, the product will warp over time -- without question. Just depends on the rate and frequency of humidity fluctuations.

I like the implementation of Expanded Foam PVC (XPVC) in snake racks. While it is heavier than plywood, it is resistant to warping. Its also waterproof, doesn't chip like melamine, and looks more attractive in my opinion. Its more expensive than melamine products, but it will last much longer. Because they're lighter, they can be stacked to save valuable square footage. However, XPVC must be purchased from a plastics distributer, and hopefully from on that will cut the sheets to specifications on your behalf for a decent price. Not everyone has a plastics distributor in their city, so some people are deterred by the need to travel for supplies.

After building so many racks, I will definitely be using only XPVC from now on. When weighing the pros and cons, there is no question -- in my opinion of course.

Quote:

---

Originally Posted by PsychD_Student

I've built abut 20 racks in the past year, consisting of at least 5 different designs. Here's some thoughts I have about some of your points/concerns.

Firstly, melamine is a wood based product that is thermally fused to melamine resin, which makes a strong and waterproof material. It is HEAVY. It also will not warp over time like you would see in almost any kind of plywood product. Warping is associated with fluctuations in humidity within the wood structure over time. This is often exacerbated by the natural grains and imperfections within the natural wood structure found in plywood. Bottom line: Melamine is heavy as hell, but is also waterproof and will be more resistant to warping. Its not toxic to snakes either. I think if you used plywood, the product will warp over time -- without question. Just depends on the rate and frequency of humidity fluctuations.

I like the implementation of Expanded Foam PVC (XPVC) in snake racks. While it is heavier than plywood, it is resistant to warping. Its also waterproof, doesn't chip like melamine, and looks more attractive in my opinion. Its more expensive than melamine products, but it will last much longer. Because they're lighter, they can be stacked to save valuable square footage. However, XPVC must be purchased from a plastics distributer, and hopefully from on that will cut the sheets to specifications on your behalf for a decent price. Not everyone has a plastics distributor in their city, so some people are deterred by the need to travel for supplies.

After building so many racks, I will definitely be using only XPVC from now on. When weighing the pros and cons, there is no question -- in my opinion of course.

---

Melamine is in the plastics family. It is not wood based at all but based in formeldehydes. It is bonded with urea formaldehyde glue to a particle board substrate. The substrate out gasses formeldehydes for at least ten years. This is proven to cause cancer in humans it is unknown what it will do to reptiles. The 'newer' low voc particle boards use phenolic resin glues that can leach phenols that are known to be toxic to reptiles.

Particle boards are not water proof at all they in fact are prone to water damage and are hydroscopic (attract water from the air). It is super easy to prove place a small 'stick' of plywood and a stick of melamine and particle board substrate in water and see which comes apart first. Plywood survives weeks if not months in water some will stand up to far far longer ( years) the substrate melamine is glued to often will swell and start to come apart in days.

Melamine is heavy and weak compared to weight. It is close to the weight of solid oak or ash wood and less than 1/4 as strong.

The only thing it has going for it is cost. It is cheap.

All wood based material will warp and change shape melamine particle board will sag under its own weight. Low quality plywood a often warp if miss handled high quality are very stable and resist warping. A design with the properties of the material used considered can easily overcome the movement of that material. Warping in a plywood construction is not poor materials but poor design and understanding of the material.

I agree with the clear choice is a plastic material or hybrid material of some sort. Pvcx is ten times lighter than fir ply! Pvcx (komatex) is 0.5 gm/ cm2 and fir ply is 5gm/cm2 way way heavier. Plywood is quite a lot stronger as well not that the strength is needed in a rack. laminated woods are very difficult to beat strength to weight.


Sent from my iPhone using Tapatalk