Help with drying / curing cypress slabs

[a12100]

I have access to a fallen cypress tree, I want to take 2 cross section slabs and make end tables for indoor use. Can anyone help with some info on how to dry cypress. I have heard its hard, and that you should soak it first and then let it dry before you even touch it. This is my first project with cypress or any drying of wood. I would appericate any information that you can provide. Thank You.

[Den Socling]

I have no experience with cross cut cypress slabs but I would guess that you have only one option - PEG. That's polyethylene glycol 1000. It's the stuff that keeps chocolate from melting in your hands and not the stuff that keeps your radiator from freezing. The molecular length (1000) makes the difference. Get a few pounds (depending on the size of your slabs - it's expensive). Make a plywood tank lined with plastic to hold the water/PEG solution. Soak the slabs and the wax-like PEG fills the cells and prevents shrinkage and the resulting cracks.

Do some research on the internet to find suppliers and they will suggest solutions and soak times.

[Bro. Noble]

Welcome to the Forum both of you !

Happy Birthday Den !

Noble

[Tom]

Thanks Den,
Why didn't I think of PEG?  I was searching my brain from front to back, a short trip, and all I could think of was slow drying and sealing with wax.  

I have a friend who turns bowls and he used PEG one time. I don't remember his talking about expense but he quit because he became afreaid of the toxicity that may occur in a bowl that could be used for food.

Charlie talked about Soap on the Forum once and the bowl machine thread that Jeff started talked about steaming.  I wonder if those would have any merit?  

[Frank_Pender]

Fellas, I am using Anchor-Seal on all of the slabs I have been cutting.  I do not know anything about cypres trees other thanwhat I saw at the Gardens in florida in 1964 with a whole lot of lovely ladies in southern Bell types of garbs.  

 Anyway, I would suggest trying the Anchor-Seal as it is working very well on my Maple and Walnut as well as the Fir slab in the picture I post some time ago.

[Don P]

As I've been looking around seems like everything from PEG 600 to about 4000 has been tried on wood. The thicker stuff is apparently hard to get penetration with. What I can't find is a cheap(er) source of this. Its used in tons of stuff, is non toxic and seems to be plentiful...but I've not seen a source other than the specialty marketers, I've got big ideas if the price were lower.
Charlies post on soapy bowls really got my gears turning. One comment was that the surfactants might be the beneficial agent...ag folks use surfactants all the time in sprays...maybe one of them? Now we're back to where my head flopped over in chem class .

I think where Tom and Frank are using the time honored method of very slow drying trying to keep the outside from drying too fast and splitting over the still green and plump core, the other school of thought is to "bulk" the cell, displacing the moisture with something that will not evaporate, preventing shrinkage.
Fireside Log Homes has been doing this with a pressure vessel and logs and claims success. They sent me some micrographs that looked good, with the PEG obviously saturating the cell wall. I'm not sure where in the log they came from though.
I guess penetration on something large is my question. Although one thought is that as long as the shell is bulked for deep enough and long enough to protect the shell from splitting, the core starts to dry to a point where it begins to shrink, a stress reversal starts and begins to pull from the interior .
PS, Welcome guys, and don't take any of that as gospel,  I'm  just a carpenter pondering on an upturned sheetrock mud bucket  

[Den Socling]

Hi Frank,
Anchorseal is a parrafin emulsion, I believe, that slows the drying when it sticks to the outside of wood. PEG goes into the wood and prevents the cells from shrinking by replacing the water.
Den

[Tom]

What does pressure cooking or steaming do, Den.  Jeff  showed a pressure cooker being used for bowls in a previous post.

http://www.forestryforum.com/cgi-bin/board/YaBB.pl?board=sawmill;action=display;num=1030810254;start=1

[CHARLIE]

In woodturning, there is always a battle going on trying to keep the wood from splitting without having to wait an eternity to finish the turning.

It is my understanding, that while PEG will prevent the splitting, it also prevents you from putting any kind of finish on the wood.

DonP had recently sent me a note asking if I've heard anything more about the use of Dish Detergent soap and I replied "no'. Right after my reply, a "Guest Commentary" by Leif Thorvaldson was printed in my Woodturning Club newspaper. It's lengthy and I was going to just send to DonP, but since this subject has come up again, I'll put it here for everyone.  I think it is worth your while to give it a try.

The Soap Solution
Having a reawakening to the pleasures of woodturning after a gap of 4 years, I plunged into it with enthusiasm. Joining the South Puget Sound Chapter AAW, buying books and videos and eagerly reading all the posts on rec.crafts.woodturning along with visiting every site, both personal and commercial. I became increasingly discomfited by what I read and learned. Experienced turners and professional turners were constantly carrying on about multitudinous ways of "drying" wood to avoid cracking. One way in particular had my hasty heart dismayed when it was described that one should rough turn the wood, slather it up with various lotions and potions and let it sit for 6 months to 6 years. One was to build an enormous pile of these objects by constantly adding to the drying rack and, at the end of the 6 months (or 6 years), check to see if the roughed out blank had cracked or warped so badly as to be unusable. If not, one could then turn it to completion, finish it and hope that it wouldn't crack thereafter. Faster methods were suggested: boiling, microwaving, burying in manure piles, compost heaps, sawdust piles, storing in sealed plastic bags, unsealed plastic bags, dry paper bags, wet paper bags,  immersing or spraying with WD-40, ad nauseum. None of these did what I wanted to do, i.e., pick up a piece of green wood, turn it, sand it and finish it within a day or two without unsightly cracks occurring.

One fateful day, browsing on my computer while waiting for the first 6 months to elapse, I encountered a very lovely website by Ron Kent
( http://www.ronkent.com/RKgallery.html ). He had some beautiful Norfolk Island Pine turnings -very thin- and used some unique finishing techniques. All very nice, but what struck me was a technique he had developed for stabilizing and conditioning wood. He had tried the expensive route, but was looking for something under $50 per gallon. To make history short, he found that Costco's house brand (Kirkland) liquid dishwashing detergent mixed with an equal amount of water provided hitherto unavailable qualities in both conditioning and stabilizing of wood for almost immediate turning and finishing. I went to Costco and purchased 4, half gallon containers of the magic elizir along with a sturdy plastic storage bin of suffiecient size to hold the mixture and some bowl blanks. Upon arrival at home, I emptied the detergent into the container and added an equal amount of water. From then on, I would take primarily green wood and rough turn in one day, soak overnight, and sometimes for for several days. Surprise! They didn't crack! I have since taken green wood, rough turned it, soaked it about 4 hours and then finish turned it and finished it in 1 day. In the 6 to 8 months I have been using this technique, I haven't had one bowl crack. A few had a bit of movement, but it was very slight. I have used the following woods: black walnut, vine maple, maple, oak (kiln dried), yew, honey locust, fruiting cherry, birch, plum, apple. I have not tried madrone as I refuse to cut down the only one I have growing on my property. Needless to say, I was ecstatic and proceeded to share my "discovery" with any and all turners I knew (two) and also spread the word on rec.crafts. woodturning. A few turners were lured into trying it. Unfortunately, some people can't follow directions and tried variations on the simple recipe, which resulted in cracking. A few did it correctly and were rewarded with success. There has been some speculation as to the mechanism behind he process, but no real scientific investigation has been done. Lyn Mangiameli, John Nicklin and I have come up with the following theory, which John set to words.

"The soap solution sets up an osmotic gradient. Pure water in the wood is in more abundance than water in the soap solution, so it (the water) tries to migrate to balance the osmotic pressure. This would cause the specific gravity of the soap solution to decrease (although possibly not noticeably.)  On the other hand, the concentration of soapy stuff is higher outside the wood than in, so it tries to migrate into the wood. If it is successful in migrating into the cells, the soapy solids will get trapped as the wood dries, preventing the cells from collapsing as they do when wood dries naturally. As you point out, the soap solution is slicker than a Teflon banana peel. This may help the migration of soapy solids into the cells."

The only slight drawback to the detergent solution is that the wood should be drained for a few minutes or longer and wiped with a towel while mounting it to the headstock. A plastic sheet should be placed over the ways and eye protection should be worn (this is because of centrifugal force when turning). Try it! Your hands will be smoother, cleaner and less subject to cracking as well as your turnings.
Leif O. Thorvaldson, Eatonville, WA          

[Bro. Noble]

Don_P mentioned using surfactants as are added to agricultural sprays.  Detergents are surfactants as they make 'water wetter' ------------they reduce surface tension allowing the spray to be absorbed more readily by the plant.  This might be a more likely reason for success in using soapy water rather than osmosis or perhaps in conjunction.  If the soap solution were too strong, water would be drawn from the wood to dilute the solution-----reverse osmosis if I remember corectly.  

Noble

[Don P]

This should link back to our previous thread on PEG and soapy bowls, just click on the text below.


http://www.forestryforum.com/cgi-bin/board/YaBB.pl?board=general;action=display;num=1017025904;start=12

Near the end of the last post of Charlie's is the part about surfactants and what they might be up to...I thought/ hoped someone with an ag background would be able to latch on to it and run