Boiling Wood:How Does It Prevent Cracking?
Hank Kingwood
wood will still warp. How does boiling wood prevent/minimize cracking?
If this is a FAQ or if there is a link that explains this, please forward.
I was also told that when you boil wood it should be done at one hour
per inch of thickness. Can anyone confirm or deny?
Much thanks!
--
Hank
George
This would seemingly allow a bit more slip before the break as the wood
contracts. Wood is boiled and chemically treated in the pulping process, so
it seems to have some basis in the real world. Think Steve Russell is the
advocate for boiling, and he uses the hour/inch rule of thumb.
Next you'll hear of Liquid Dish Detergent, where an anionic surfactant is
used to help stabilize the wood. Here it's a bit more speculative, but the
effect of lowering the surface tension of the water in wood should make it
slower to draw out of the vessels by capillary action. Since surface checks
are the result of a dryer surface over a damper interior, I'm at a loss to
explain why it should make a difference. Leif will jump in and give you the
anecdotal evidence in support, but I don't believe anyone has come up with
the science.
Personally, I just keep the piece cool and let it dry "as is" at my house.
Put the fresh ones up for a few hours to get the surface water off, then to
the bottom shelf in a heated basement. Move 'em up shelves as required to
put fresher ones on the bottom. Failure rate is minimal on domestic
(Michigan) woods. If you're really cautious, you can wrap in newsprint or
bag in Kraft bags after the initial dry hours, but you have to go back and
check to make sure you're not slowing the process so much that your pieces
mildew. Change the paper when it feels damp.
"Hank Kingwood" <actio...@sbcglobal.net> wrote in message
news:3E2E8167...@sbcglobal.net...
Arch
happened to the ES90 (?) wood stabilization system invented by a
Mr.Sexton of Ga.? I recall he wanted it to be in the publlc domain and
funded by the gov't. Arch
Fortiter,
Marshall Gorrow
Check the following:
http://www.esp90.com/docs/section2.htm
It's actually, ESP90. If you treat the seeds you get twice the growth!
The wood dries faster! There is less checking!
I wonder if Leif has some interest in this? LDD? :-)
Marshall Gorrow,
Hogansburg, New York
http://mgorrow.tripod.com/
Ecnerwal
cracking is that the heat will permit the wood to bend if it is under
stress - so if the bowl has residual stresses, and would crack if it
dried a bit more, heating it will allow it to bend, relieving the
stresses somewhat, and thus possibly reducing cracks.
This may also be why microwave treatment works successfully - as it's
drying the wood, it's also heating and thus permitting some movement to
reduce stress.
Then again, I could be wrong.
rrk
Hi Marshall and Arch,
Marshall Gorrow wrote:
> http://www.esp90.com/docs/section2.htm
>
> It's actually, ESP90. If you treat the seeds you get twice the growth!
> The wood dries faster! There is less checking!
And its biodegradable too.
Soy-based.
Stops the alpha-rays.
Keeps wood from dulling cutting tools,
so no more sharpening is required.
I have worked out the Secret Formula.
If you would like to know the Secret Formula,
send your $20 contribution to me now.
This is your last chance.
Cash only please!
<smile>
--
HAVE <ôżô> FUN .......... ez
Leif Thorvaldson
soft? LDD can handle any wood from anywhere without the exasperating
tedious wait for the tree to grow, be harvested, milled and presented for
sale. Don't go off to any old siren song, lads. Be firm! Must I stop your
ears with beeswax? *G*
Leif
"Marshall Gorrow" <mgo...@hotmail.com> wrote in message
news:21508-3E...@storefull-2198.public.lawson.webtv.net...
Ray Manning
lowered since the wood dries faster. Perhaps breaking down the lignin allows
quicker moisture exchange? Perhaps boiling bursts the water containing
cells? Donno, and I could also be wrong.
"Ecnerwal" <Lawren...@SOuthernVERmont.NyET> wrote in message
news:3E2F4078...@SOuthernVERmont.NyET...
Andi Wolfe
> Presumably, it weakens the lignin, the "binder" in the wood, by denaturing.
> This would seemingly allow a bit more slip before the break as the wood
> contracts. Wood is boiled and chemically treated in the pulping process, so
> it seems to have some basis in the real world. Think Steve Russell is the
> advocate for boiling, and he uses the hour/inch rule of thumb.
Actually, it's not the lignin that changes chemical properties through
boiling, but the hemicelluloses. Lignin is insoluble in water and has
a higher melting temperature than what you'd get with boiling water.
To change the chemical properties of lignin you'd have to add
something like sodium hydroxide to weaken the bonds it forms within
and among cells.
By boiling wood you are affecting the ability of the wood to take up
and lose water from the atmosphere. You lose the moisture gradient
that occurs with some tissue regions losing water faster than others,
which is where the stresses of drying cause cracking.
Wood is a very complex plant tissue, consisting of many different
types of cells with different materials deposited in the cell walls.
The susceptibility of some woods to cracking as compared to others is
because of the characteristic differences in the relative amount and
positioning of: (1) water-conducting cells (lignified cells such as
tracheids and vessels, collectively called xylem), (2) fibers
(lignified cells that do not conduct water), and (3) non-lignified
cells (e.g., parenchyma rays). To further complicate this, you have
differences in the materials transported into the heartwood, and
whether or not tyloses form in the vessel elements. Tyloses are
basically plugs of cellulose-like material that stops the flow of
water in older tissues.
Andi
(apologizing again for an introductory botany lesson)
Kip055
Andi
I'm sure that some of us appreciate the botany lesson-know that I do. I don't
want to start a civil war, but do you have a hypthesis on use of LDD? (In my
own limited experiments, it seems to sometimes help, sometimes not). I'm
unaware of any input from folks with a botany backround and think int might be
interesting.
Kip Powers
Rogers, AR
Leo Lichtman
Leif Thorvaldson wrote: ESP90 is all very fine and good, but does it leave
your hands clean and soft?
LDD clearly does not prevent *wise-cracks.*
Mike Paulson
It's nice to have a plant biologist in the group. Thanks for sharing your
expertise. Your post raises some questions in my feeble brain cells. I
hope you are willing to educate us further.
>>Lignin is insoluble in water and has a higher melting
>>temperature than what you'd get with boiling water
Is it possible that the heat from boiling softens the lignin enough to
relieve stress in the wood?
What are "hemicelluloses"?
>>You lose the moisture gradient that occurs with some
>>tissue regions losing water faster than others
Would you care to expand on that? My understanding was that end grain
lost moisture much faster than side grain. Does this mean that boiling
causes side grain to lose moisture more rapidly?
I have done little boiling, but my perception is that it helps situations
where the pith is running through the side of a vessel, in which case it
is end grain surrounded by end grain. Do you think boiling actually does
make a difference in such cases? If so, why would that be?
thanks for your help,
-mike paulson, fort collins, co
Notal Kyder
Your information is correct Hank but in my opinion it's just too much
work. I just force myself to be patient. I rough out lots of bowls and
store them in my basement for a few months and they are ready to be
finish turned. Boiling is a lot of work and can be dangerous. You need
a fairly larg kettle for most of the work I do and I'm just not that
keen on starting a fire in the back yard,boiling a big pot of water
and boiling my bowls.
Notal Kyder
Andi Wolfe
an update after the books I've ordered from the library are delivered.
This thread gave me an opportunity to do some quick research from the
abstracts available online, but I'll need to do some additional
reading to better understand what happens to wood from the combination
of heat and water.
> Is it possible that the heat from boiling softens the lignin enough to
> relieve stress in the wood?
Yes, this is possible. Lignin is thermoplastic, which means that it
becomes pliable at high temperature and then becomes hard again when
the temperature is lowered. That's why steam bending of wood is so
effective. I'll go into more detail about lignin in a few sentences
below.
> What are "hemicelluloses"?
I need to answer this by giving you an overview of the molecules that
make up a xylem element (water conducting cell of wood).
WARNING: this is an introductory plant anatomy lesson - not for the
faint-hearted.
Xylem cells consist of three types of molecules:
1. Cellulose (50%), which is a long chain of glucose (a type of
sugar) molecules strung end-to-end. There are up to 30,000 glucose
molecules in each molecule of cellulose. Cellulose doesn't have a
branching structure - think of it as a long chain of individual links
(or as a long string of pearls with each pearl representing a glucose
molecule). However, the glucose molecules in the cellulose can form
chemical bonds with other molecules, including other glucose
molecules. When two molecules of cellulose come into contact, the
glucose molecules along the length of the chain can bond to each
other. Visualize a single ply of yarn wrapping around another strand
to form 2-ply. The two strands together are much stronger than either
one is alone.
2. Hemicellulose (20-25%) is a combination of cellulose and other
types of sugars added besides glucose. This molecule has branched
chains instead of straight chains. Hemicellulose wraps around strands
of cellulose to form a structure called a microfibril.Microfibrils
form a mesh (skeleton) around the cell wall that is very strong.
When xylem cells first form, the microfibrils are not strongly
connected to one another. As water enters the cell, the cell wall can
stretch.
3. Lignin (25-30%). Lignin is a more complex molecule that is made
up of sugars and molecules with ring structures (e.g., phenolics). It
has a three-dimensional structure because of how the components within
this molecule interact with one another. Lignin is what glues
microfibrils together in the cell wall, and is what gives the cell
wall the structural support to allow tree stems to grow so tall.
In young xylem cells the lignin is deposited in a spiral around the
cell wall. That means the cell can continue to expand during
development. As more an more lignin molecules are embedded in the
cell wall, the cell wall loses its ability to stretch. Eventually the
cell dies and you end up with an empty shell made of cellulose,
hemicellulose and lignin.
The sugars making up cellulose and hemicellulose can bind to water.
When water is bound to molecules in the cell wall, you reach the fiber
saturation point. The amount of moisture held in cell walls ranges
from 20 - 35%. Beyond this amount of moisture, water enters the cell
interior cavity, and you can have the transport of free water from one
part of the plant to another. When all the cells are filled with
water, you have maximum saturation. That's generally the stage you
have when a tree is cut. When green wood is exposed to air, you have
evaporation of the free water first followed by the loss of water held
in the cell walls.
Now, for the next part of your query:
> Would you care to expand on that? My understanding was that end grain
> lost moisture much faster than side grain. Does this mean that boiling
> causes side grain to lose moisture more rapidly?
>
> I have done little boiling, but my perception is that it helps situations
> where the pith is running through the side of a vessel, in which case it
> is end grain surrounded by end grain. Do you think boiling actually does
> make a difference in such cases? If so, why would that be?
Wood shrinks and swells when it loses or gains moisture below/above
the fiber saturation point. Remember that it is the cellulose and
hemicellulose molecules in the cell wall that bind to water.
When moisture escapes from cellulose and hemicellulose, those
molecules can move closer together - in effect, shrinking the wood.
The amount of wood shrinkage is correlated with the amount of lost
water, and the shrinkage differs in degree depending on the direction
(perpendicular, parallel or at an angle) from the orientation of the
xylem elements (stacked on top of one another to form straws). This
can result in a change of shape (e.g., warping), checking or
honeycombing, and case hardening.
Checking occurs because of the moisture gradient that develops across
a section of wood. As water is lost from the outside surface, those
cells shrink as the cellulose and hemicelluose molecules move closer
together. Water is lost faster from endgrain as compared to side
grain because more of the cell wall surface is exposed (think stacks
of straw holes as opposed to the side of the straw). Unfortunately,
the cells toward the inside of the section are still saturated with
water and don't move. However, they're still connected to the cells
toward the outside and so you end up having a rip in the tissue when
the tug of war between the two areas begins. Eventually the outer
section becomes stable as the stress is released, but now the inner
section loses water from its cell walls. Those cells now begin to
shrink, but the outside is stable and causes stress on the inner
cells. Another tug of war ensues . . . rip!
So, what I think is happening with the boiling is that the chemical
structure of the hemicellulose and cellulose changes, making them less
able to gain or lose water. Because of this, you won't have the
stresses I just described starting in the first place.
I apologize for the very long answer, but I think the background info
on wood anatomy was needed to explain that last paragraph.
Andi
(who at the moment is heading for the shop to relieve some wood stress
accumulated during this long-winded response)
Brad
I have a question, though: Might boiling alter impermeable or
semi-permiable membranes to make the cell walls more "porous" or to
destroy some component of the cell structure to basically blast tiny
holes in the structures that would normally prevent the free movement
of water (thus lowering any moisture gradient between the inner and
outer wood) ? I have a sneaking suspicion this is a component of the
soap process, too, although I have a lot more exposure to animal
tissues than plant. When I was a laboratory wonk, we used to use
Triton X-100, and other detergents & surfactants as a way to get
various substances to penetrate cell membranes. The detergent (also a
surfactant) literally dissolved some of the molecules in the cell
membranes, rendering them more porous. By allowing water to move more
freely between cells, we ought to lower any moisture gradient that is
set up by evaporative drying, and also get the wood to dry more
quickly without cracking -- both soap and boiling claim to do this.
Your thoughts ?
Safe Spinning,
Brad Vietje
East Thetford, VT
Andi Wolfe
With regards to LDD - we're talking about a substance that is a
surfactant. What that means is that it coats the cell walls and
reduces the affinity of the cell wall to water. Displacement of water
+ loss of binding ability = reduced stress because the moisture
gradient is lost.
The success of LDD in preventing checking and warping will depend on
the specific nature of each wood. I suspect that dense woods will
respond differently than less dense ones, and that diffuse porous and
ring porous woods would also behave differently. I'll defer to Dr.
Soapy, himself, for testimonials regarding the attributes of LDD for
different species of trees.
Andi
kip...@aol.com (Kip055) wrote in message news:<20030123111237...@mb-fv.aol.com>...
Leif Thorvaldson
Leif
"Andi Wolfe" <Andi...@yahoo.com> wrote in message
news:6150bf34.0301...@posting.google.com...
Owen Lowe
Andi...@yahoo.com (Andi Wolfe) wrote:
> Actually, it's not the lignin that changes chemical properties through
> boiling, but the hemicelluloses. Lignin is insoluble in water and has
> a higher melting temperature than what you'd get with boiling water.
> To change the chemical properties of lignin you'd have to add
> something like sodium hydroxide to weaken the bonds it forms within
> and among cells.
Isn't sodium hydroxide lye? For someone who had a real tough time in
Chemistry 101, me, it would seem as though some components of the
detergent solution would mimic (at a much lower effectiveness) the
actions of sod. hydroxide... ?
_____
Member AAW Chapters:
Cascade Woodturners Assoc., Portland, Oregon
Northwest Woodturners, Tigard, Oregon
_____
Anny van der Loo
Hello Dr. Leif soapy Thorval
Is this a call for boiling in LDD now (gr)
Andi Wolfe
I'll have to answer this by continuing the plant anatamy lesson posted
above.
>
> I have a question, though: Might boiling alter impermeable or
> semi-permiable membranes to make the cell walls more "porous" or to
> destroy some component of the cell structure to basically blast tiny
> holes in the structures that would normally prevent the free movement
> of water (thus lowering any moisture gradient between the inner and
> outer wood) ?
If the mature xylem cell had a cell membrane, this might be a possible
explanation. However, the mature xylem cell has no membrane or other
cellular components aside from the cell wall. During cell
development, connections between the vessels and tracheids (the two
types of xylem cells) are established as either openings in the
endwalls or pores in the side walls. This is the only time during
development that you have connections between cells that are analagous
to animal cells (direct connection through structures in the
membrane). This is not a long-lived stage, however. Mature xylem
tissue is dead - no nucleus, no chloroplast, no ribosomes or other
organelles, and no cell membrane.
Water moves through vessels and tracheids through a force called
transpiration pull combined with capillary attraction. Water enters
the roots through living cells called root hairs. Water makes its way
to the core stele and enters the xylem stream, which has a continuous
connection from the roots to the leaves (and other plant organs, for
that matter). Water is evaporated away from the leaves through the
process of transpiration. This is a strong force for movement because
the xylem cell diameters are so small. Capillary attraction is the
same phenomenon you have when two pieces of glass come into contact
and a drop of water is trapped between them - the water creeps away
from the point of contact in every direction. During drought years
you can sometimes hear the breaking of the capillary stream of water.
Walking through an oak forest in times of drought, you can sometimes
hear the distinct pops of cavitation - when the transpiration pull is
insufficient to maintain the water column in the vessel.
> I have a sneaking suspicion this is a component of the
> soap process, too, although I have a lot more exposure to animal
> tissues than plant. When I was a laboratory wonk, we used to use
> Triton X-100, and other detergents & surfactants as a way to get
> various substances to penetrate cell membranes. The detergent (also a
> surfactant) literally dissolved some of the molecules in the cell
> membranes, rendering them more porous. By allowing water to move more
> freely between cells, we ought to lower any moisture gradient that is
> set up by evaporative drying, and also get the wood to dry more
> quickly without cracking -- both soap and boiling claim to do this.
> Your thoughts ?
Surfactants do disrupt cell membranes - you are absolutely correct.
However, given the absence of cell membranes in mature xylem, the
surfactant properties of LDD are more likely to interfere with water
binding to microfibrils, which will affect the fiber saturation point
and reduce the moisture gradient.
Hope this helps to clarify my previous post.
Andi
Andi Wolfe
Lye is the liquid you get when you leach wood ashes. It contains
potassium hydroxide and sodium hydroxide. Both chemicals are bases.
The concentration of sodium hydroxide in soap is very, very low.
Grandma's lye soap might have been able to take the skin off your
knees, but we have consumer protection laws for industrially-produced
soap.
When wood chips are processed into pulp, the concentration of chemical
bases used in the treatment is relatively high, plus you add heat to
the mix -- voila! the breakdown of wood into fibers. Stinks to high
heaven, I might add - used to live in the Pacific Northwest where
paper mills used to be a dime a dozen.
Andi
Owen Lowe <onln...@easystreet.com> wrote in message news:<onlnlowe-A1148C...@corp.supernews.com>...
william_b_noble
ought to try it sometime:
the image - a bearded man with a face shield, a CLTL T-shirt and lots of
shavings in his hair is holding a paddle from a canoe, stiring a huge vat
full of bowls. the vat is sitting on a campfire outside (think of the
canibals in the jungle boiling the missionary). Soap suds are comming out
of the vat, lifting bowls from the vat high into the air. The suds are well
above the roof line and are spreading across the countryside.
You can add your own caption, including:
"just one more hour and the'll be permanently crack free"
"I love the smell of well cooked ash"
"and they say ash to ashes, oak to oak, if I don't boil these bowls, they
all will be broke"
<place your captions here>
"Anny van der Loo" <l.van...@rogers.com> wrote in message
news:3E30F9BA...@rogers.com...
Arch
simmered bowls. Arch
Fortiter,
Mike Paulson
>>all will be broke
If I may paraphrase, this one's for you, Dr Soapy:
Rough bowls from ash
More bowls from oak
Put them in LDD
Then let them soak...
-myke appalled son, four callings, collar add oh
Leif Thorvaldson
there were a lot of paper mills in WA! The Tacoma Aroma mill put out enough
noisome odors to seem to indicate there were many more of them than there
was! Enough of this gratuitous criticism of WA, or I might reveal how the
glue factory in downtown Columbus, OH reeked! *G*
Leif
"Andi Wolfe" <Andi...@yahoo.com> wrote in message
news:6150bf34.03012...@posting.google.com...
Leif Thorvaldson
*BLUSH*
Leif
"Mike Paulson" <mpau...@nyx10.nyx.net> wrote in message
news:10434270...@irys.nyx.net...
George
"Leif Thorvaldson" <Le...@mashell.com> wrote in message
news:v335kok...@corp.supernews.com...
Leo Lichtman
Liquid dishwashing
Detergent bubbling over
Wooden bowls awash.
Andi Wolfe
where I grew up. My brother liked the smell of the Albany mill -
thought it smelled like baked ham. The rest of us held our noses as
we drove past it on I-5.
"Leif Thorvaldson" <Le...@mashell.com> wrote in message news:<v335kok...@corp.supernews.com>...
> Now wait just a cotton pickin' minute, der Andi! It only "seemed" like
> there were a lot of paper mills in WA! The Tacoma Aroma mill put out enough
> noisome odors to seem to indicate there were many more of them than there
> was! Enough of this gratuitous criticism of WA, or I might reveal how the
> glue factory in downtown Columbus, OH reeked! *G*
Can't say I've had the pleasure of this olfactory experience. Maybe
it went away before I arrived in "cowtown." Probably didn't compare
to the sugar beet factory on the outskirts of Nampa, Idaho, though. I
used to have to ride my bike along that road in the summer on my way
to and from work after I left Oregon for my first years at college.
You'd think that experience would have prepared me for raising kids
(what the heck is that smelly blob under the bed????? - maybe Molly
and Ruth can identify with me on that one), but I guess some things
are best forgotten anyway...
Andi
Arch
I hope your brother didn't become a chef. Nothing like the aroma of
baked Va ham. Maybe like the gristle served as ham at rest stops along I
95. The paper mills in N. Fla. digest the wood with chemicals, and the
smell is awful many miles away. In Maine the mills use heat and there is
almost no odor. Or maybe slash pine and Maine pine digestants smell
differently. I'm not sure that all rcw is wild with excitement on
learning this. ;) Arch
Fortiter,
Duncan McEwan
> where I grew up. My brother liked the smell of the Albany mill -
> thought it smelled like baked ham. The rest of us held our noses as
> we drove past it on I-5.
>
Scio, about 17 miles northeast. When we could smell the mill in Scio
we knew it was going to rain.
duncan
Steven D. Russell
I have been out of town for this discussion and away from the 'net. Looks
like Andi has filled in for me quite nicely... :-) as a long time proponent
of boiling wood to reduce drying degrade and speed the drying process, its
nice to see another scientific view about the process.
When I first published my boiling protocol, I never imagined it would stir
the emotions of woodturners around the world. Although many still think it's
hogwash, hundreds of woodturners have begun to use my protocol and are
experiencing the same outstanding results as I have seen in my studio.
BTW, my post boiled success ratio (success = NO checking in pieces taken
from wet boiled pieces, to seasoned) is still averaging 96% - 98.5%,
depending on the species. None too shabby by me!
--
Better Woodturning and Finishing Through Chemistry...
Steven D. Russell
Eurowood Werks Woodturning Studio
"Woodturning with Steven D. Russell" CD now available!
21 articles with more than 93,000 words and 500 photos. Email for details.
Machinery, Tool and Product Testing for the
Woodworking and Woodturning Industry
The Woodlands, Texas
"Hank Kingwood" <actio...@sbcglobal.net> wrote in message
news:3E2E8167...@sbcglobal.net...
> I've heard that boiling wood helps prevent/minimize cracking but the
> wood will still warp. How does boiling wood prevent/minimize cracking?
> If this is a FAQ or if there is a link that explains this, please
forward.
>
> I was also told that when you boil wood it should be done at one hour
> per inch of thickness. Can anyone confirm or deny?
>
> Much thanks!
> --
> Hank
>
Leif Thorvaldson
Like chicken soup sans boil and bubble
Of no great toil and trouble,
LDD will cause your spirits to bubble.
------------
LDD: Success rate currently at 98.5% -- 100.2%!
Doc Soapy
"Steven D. Russell" <ben...@flash.net> wrote in message
news:8JGZ9.155$UU.18...@newssvr15.news.prodigy.com...
Leo Lichtman
Leif Thorvaldson wrote:
For a charm of lesser trouble.....
*************
Leif, your doggerel makes me catatonic :-)
*************
Leif wrote:
LDD: Success rate currently at 98.5% -- 100.2%!
I'm holding out for a higher figure, since the margin of error could put you
down to 100%, or even less!
Leif Thorvaldson
Shakespeare poetry shouldn't do that!
cata·ton·ic1 ('kat-?-`tän-ik)
adj.
". . . disturbance that may involve stupor or mutism, negativism, rigidity,
purposeless excitement, and inappropriate or bizarre posturing.
Lay on, MacLichtman! *G*
Leif
"Leo Lichtman" <l.lic...@worldnet.att.net> wrote in message
news:hdIZ9.8728$rq4.7...@bgtnsc05-news.ops.worldnet.att.net...
