Re: Hi i need help.. Does yakal can be kiln dry?

If you're quoting him accurately, that guy is so wrong ...and so right.

Yakal has regularly been, regularly is, and regularly will be kiln dried.
However (TM)... the thicker your lumber, the lower the temperature
and the longer the time in-kiln has to be, otherwise you risk checking,
which is what happens when outer portions of wood dry and shrink
much faster than its inner portions.

As you approach the low-end of kiln temperatures (mid 40's Celsius)
in an attempt to avoid checking, you get closer and closer to ambient,
at which point one might ask (and as the guy you spoke to may have
been thinking): it's only just a few degrees cooler outdoors, so why
not just air-dry those 4x11x7 badboys?*

The problem with air-drying is our erratic temp and humidity.
Several days of hot-and-dry will cause your lumber to check anyway.
Days of windless high-humidity will virtually arrest (or reverse) the
drying process. It also takes considerably longer to air-dry lumber,
even with benevolent weather, than to go the KD route. Finally, and
because of the foregoing, it takes quite some skill to gauge when
lumber has been sufficiently air-dried.

*Keep in mind that it's possible your boards won't be the only ones to
go into the kiln, and the kiln-op loses money if they dial EVERYTHING
down for the sake of your oversize pieces. If the op's business is based
on mostly softwood or smaller-section (2x2) hardwood, they're used to
running things at a high temp and higher air velocity. A fast turnover
means more money for them.

If you're quoting him accurately, that guy is so wrong ...and so right.

Yakal has regularly been, regularly is, and regularly will be kiln dried.
However (TM)... the thicker your lumber, the lower the temperature
and the longer the time in-kiln has to be, otherwise you risk checking,
which is what happens when outer portions of wood dry and shrink
much faster than its inner portions.

As you approach the low-end of kiln temperatures (mid 40's Celsius)
in an attempt to avoid checking, you get closer and closer to ambient,
at which point one might ask (and as the guy you spoke to may have
been thinking): it's only just a few degrees cooler outdoors, so why
not just air-dry those 4x11x7 badboys?*

The problem with air-drying is our erratic temp and humidity.
Several days of hot-and-dry will cause your lumber to check anyway.
Days of windless high-humidity will virtually arrest (or reverse) the
drying process. It also takes considerably longer to air-dry lumber,
even with benevolent weather, than to go the KD route. Finally, and
because of the foregoing, it takes quite some skill to gauge when
lumber has been sufficiently air-dried.

*Keep in mind that it's possible your boards won't be the only ones to
go into the kiln, and the kiln-op loses money if they dial EVERYTHING
down for the sake of your oversize pieces. If the op's business is based
on mostly softwood or smaller-section (2x2) hardwood, they're used to
running things at a high temp and higher air velocity. A fast turnover
means more money for them.

Wow nice answer sir.. Very very informative.. Does these apple to all hardwoods,? Like tugas sir? Coz im planing to cut it To 2" so that it will have a faster time to dry.. .. Mden i can used to in 6months time.. Does yakal and tugas shrink sir? How many mm does they shrink for example 2" green wood...
I have notice that the end part of the 4" x 10 x7 cracks a little bit..
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Re: Hi i need help.. Does yakal can be kiln dry?

Wow nice answer sir.. Very very informative.. Does these apple to all hardwoods,? Like tugas sir? Coz im planing to cut it To 2" so that it will have a faster time to dry.. .. Mden i can used to in 6months time.. Does yakal and tugas shrink sir? How many mm does they shrink for example 2" green wood...
I have notice that the end part of the 4" x 10 x7 cracks a little bit..
Posted via PHM Mobile

Not all hardwoods dry out at the same rate, because of differences in
porosity, cell structure and greenwood MC (moisture content). There
have been several papers published (here and abroad) attempting to
differentiate hardwoods into drying classifications.

By just one of those papers (which do conflict with one another)...
Vitex parviflora (molave/mulawin/tugas) is a schedule 10 hardwood,
which indicates, among other things, that it is better dried out more
slowly than schedule 9 Shorea astylosa (yakal).

Shrinkage is a natural result of drying, and there are also a lot of
papers published on how much shrinkage to anticipate per species,
but we all know that even two trees of the same species will have
differences in wood density. There will even be differences between
wood taken from different parts of the same tree, but....

You generally can lose as much as 12% greenwood dimension, in
drying to an MC of 12%. It depends on species of wood and HOW
lumber was cut (tangentially, radially, longitudinally). Shrinkage is
most severe ALONG the growth rings.

The end of a drying piece of lumber is so susceptible to checking
because all five sides are drying out and want to shrink, but the
core of the lumber is still wet and does not want to shrink. It's a bit
like that old Sanforized shirt TV commercial: the rain makes this
un-Sanforized shirt shrink on the guy wearing it, and since the guy
himself isn't shrinking, the shirt tears itsef apart.

Not all hardwoods dry out at the same rate, because of differences in
porosity, cell structure and greenwood MC (moisture content). There
have been several papers published (here and abroad) attempting to
differentiate hardwoods into drying classifications.

By just one of those papers (which do conflict with one another)...
Vitex parviflora (molave/mulawin/tugas) is a schedule 10 hardwood,
which indicates, among other things, that it is better dried out more
slowly than schedule 9 Shorea astylosa (yakal).

Shrinkage is a natural result of drying, and there are also a lot of
papers published on how much shrinkage to anticipate per species,
but we all know that even two trees of the same species will have
differences in wood density. There will even be differences between
wood taken from different parts of the same tree, but....

You generally can lose as much as 12% greenwood dimension, in
drying to an MC of 12%. It depends on species of wood and HOW
lumber was cut (tangentially, radially, longitudinally). Shrinkage is
most severe ALONG the growth rings.

The end of a drying piece of lumber is so susceptible to checking
because all five sides are drying out and want to shrink, but the
core of the lumber is still wet and does not want to shrink. It's a bit
like that old Sanforized shirt TV commercial: the rain makes this
un-Sanforized shirt shrink on the guy wearing it, and since the guy
himself isn't shrinking, the shirt tears itsef apart.

Again horge thank you so much for your reply.. And answer.. Today.. I did go to one kiln dryer here in cebu .. cebu universal lumber one of the best lumber site in cebu and huge stock of mangkono , and kamagong... And ask if they are willing to kiln dry yakal wood.. And The answer is Yes they can but.. Its my risk if the wood will crack .. And he explain it to me that they will kiln dry it along with the soft wood and some hardwood . they cant individually kiln dry my wood and it will take 1month and 15days . They advice me to better to air dry it.. And explained it to me that the only wood they dont kiln dry is yakal only bcz of the wood is different from molave and narra..
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Not all hardwoods dry out at the same rate, because of differences in
porosity, cell structure and greenwood MC (moisture content). There
have been several papers published (here and abroad) attempting to
differentiate hardwoods into drying classifications.

By just one of those papers (which do conflict with one another)...
Vitex parviflora (molave/mulawin/tugas) is a schedule 10 hardwood,
which indicates, among other things, that it is better dried out more
slowly than schedule 9 Shorea astylosa (yakal).

Shrinkage is a natural result of drying, and there are also a lot of
papers published on how much shrinkage to anticipate per species,
but we all know that even two trees of the same species will have
differences in wood density. There will even be differences between
wood taken from different parts of the same tree, but....

You generally can lose as much as 12% greenwood dimension, in
drying to an MC of 12%. It depends on species of wood and HOW
lumber was cut (tangentially, radially, longitudinally). Shrinkage is
most severe ALONG the growth rings.

The end of a drying piece of lumber is so susceptible to checking
because all five sides are drying out and want to shrink, but the
core of the lumber is still wet and does not want to shrink. It's a bit
like that old Sanforized shirt TV commercial: the rain makes this
un-Sanforized shirt shrink on the guy wearing it, and since the guy
himself isn't shrinking, the shirt tears itsef apart.

Posted via PHM Mobile