I'am just winging it. I tried the Poly wrap last year on a piece of OS and it checked allright, like a crevice the size of the grand canyon. I'll never try that method agian. As long as its properly sealed and sitting outside in the hot sun it should be ok.
I forgot to mention after cutting my wood I first burn the ends untill black, then I use a sealer, usually Varathane. The Varathane has never let me down.
This may help you out, its an expensive may to go.......
Never tried it myself.
PEG-1000
PEG-1450
Instruction Sheet
Polyethylene glycol (PEG) is a chemical treatment used on green wood to prevent
warping, cracking and shrinking. PEG is a white waxy substance that is solid
at room temperature. It is non-toxic, non-flammable and soluble in water. No
special safety precautions are required when working with it.
The numbers 1000 and 1450 refer to the average molecular weight of the polymer
chains of PEG. PEG-1000 is supplied in solid blocks and melts at 98° to 103°F
(37° to 39°C). PEG-1450 is supplied in flake form and has a higher melting
temperature, 110° to 115°F (43° to 46°C). Because of the larger molecule size,
PEG-1450 is absorbed more slowly into wood, but will not bleed from wood as
PEG-1000 will in hot, humid conditions.
Choice of Woods
For PEG to be effective, the wood to be treated must be green, with a moisture
content (MC) above 30%. PEG will not restore dry wood to its original dimensions,
nor will it stabilize already dry wood. The higher the moisture content, the more
effective PEG is. Wood at 100% MC treated with PEG will reduce its shrinkage
by 90%. Because of this, it is important to maintain the moisture content of the
wood while working it by keeping it covered with plastic or dampened sawdust.
All woods will behave differently with PEG. Woods most suitable are low to
medium in density, and with a high moisture content. Avoid woods with high
resin or oil content. Listed below are some woods that have been effectively treated
with PEG and some that have proven to be difficult to treat.
TREATABLE WOODS:
Poplar, Walnut, Red Oak, Beech, Pine, Apple
Aspen, Soft Maple, Spruce, Fir, Redwood, Butternut,
Hickory, Elm, Willow
UNTREATABLE WOODS:
Cherry, Hard Maple, White Oak, Tropical Hardwoods
Preparing Woods For Treatment
PEG has a limited penetration into wood no matter how long it is left to soak.
The maximum penetration into exposed end grain is about 2". Penetration into
side grain varies from 1/2" to 1". Green wood should be worked quickly so that
as little moisture as possible is lost from the workpiece. Pieces should be worked to
within 1/4" of its final dimensions before being treated to get the best penetration
and to reduce the amount of PEG lost in shavings in final working.