Short of storage space so I put my winter boards in the attic over summer. I put a max/min thermometer in there yeasterday and it got to 105 degrees farenheit at the level of the board or 99 degrees in a board bag at the same level. The boards are on reasonably horizontal cross members but not absolutely flat. Also some are stacked on others. Can I expect twisting of other long term effects at these temperatures or slightly higher?
thanks
Mark
Cant do em’ any good.
If you expect to have them beyond the next 3-5 year timeframe then perhaps a bad idea.
Agreed - twisting, etc, aren't the problem, but delams are. While it might cure some pressure dings, still, I'd try for a cooler climate.
doc...
OK thanks I will take them out before the next hot spell.
mark
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Agreed - twisting, etc, aren't the problem, but delams are. While it might cure some pressure dings, still, I'd try for a cooler climate.
doc...
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Makes me wonder - wouldn't a vent in a poly board be a good thing?
"Am I ruining my boards by storing them in an attic at 105 degrees F?"
Yes
[quote="$1"]
[quote="$1"]
Agreed - twisting, etc, aren't the problem, but delams are. While it might cure some pressure dings, still, I'd try for a cooler climate.
doc...
[/quote]
Makes me wonder - wouldn't a vent in a poly board be a good thing?
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Ahmmm - reasonably dense polyurethane foam isn't that bad, as the wee cells of gas tend to be small and not interconnecting the way many styrene foams are. So, you won't get that much expansion, nor will you get the pressure buildup of the board as a whole looking for a weak spot in the glassing. The expansion is (mostly) in the outer skin. Lets not forget that polyurethane foam is a pretty good insulator, so temps will take a while to equalise.
On the other hand, some styrene foams are so open that water will almost pour through 'em. With those, you have what's effectively a hollow board and venting them makes a lot of sense.
The thing you do want to consider is the temperature range you're subjecting things to, like your board. And that in turn takes us to the Ideal Gas Laws: PV=nRT. Or, Pressure x Volume =number of gas molecules x a constant R x Temperature in absolute degrees, like degrees Kelvin. In the case of the gas in your board, the number of molecules is constant, as is the volume.
Playing with the numbers, and using real degrees, lets say we take a board from freezing (273 degrees Kelvin) to that hot attic ( call it 122 F, 45 C or 318 K) - your gas in your foam want to expand by 318/273 or around 17%.
Add in air pressure changes external to the board and what have you, it's not unbelievable to double that, to around a third. Add to that that while polyester resin is a thermosetting plastic, it does soften a little at elevated temps and you can have some real problems.
Oh, and....ever leave your board out in the sun, say on top of the car or in the bed of an open pickup? 120F isn't the number then, especially if you went nuts with the tribal ( black or other dark colored) graphics. Those get really hot, you can just watch 'em bubble up if you're patient. If you were to touch one of those oh-so-cool black squiggles, you'd find it's not cool at all, more like hot enough to blister your skin.
Call it 80C, not quite boiling. 353 K, resin gets quite soft too. and you're in for a definite delam repair.
The moral of the story? Heat isn't kind to plastic. So, be kind to it, make it last.
doc...
105 F isn't going to hurt (all of us in FL who keep boards in garages or sheds would be in trouble if 105 was a problem, haha), but putting boards on top of each other when not supported correctly could well be.
Try to avoid ANY forces that can impart twist when storing boards. This includes the boards own weight on unleveled supports, boards (or other things) on top of boards, etc. If your rafters aren't level, store the boards deckside down, they should only contact wood at center provided there's some deck dome in shape. A 3-point support or leveled 4-point is best for horizantal storage, and needed if storing deck-up.
105 degrees shouldnt be a big issue...as mike said people in florida...the carolinas...places in california...etc would all have warped twisted boards if this were the case...just dont put any additional weight on them (same as storing them in 50 degrees)...and you might want to scrape the wax before you store them..haha