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Is there a Doctor in the house?

Pages: 1 15 replies

B

Calling all Tiki Doctors to the E.R. stat!!!!! Okay fellas here is the problem. My "wifes" palm wood tiki is in the process of rotting from the bottom. We discovered this after moving "Big Kahuna" from her sisters house in Tampa back to Sebastian. The rot extends up to about three inches into the middle of "BK". She seems to think that multiple coats/soaking the bottom with Teak Oil will do the trick. I think that a fiberglass resin(Git Rot) used on boats would work better. Any feed back would be greatly appreciative.. Take care and be safe.

Glen L.

A

Hiya Bullgator!

What kind of rot are we talking about? If it's mushy rot, you're gonna want to carefully replace the moisture with some kind of bulking agent (like sucrose) so that the wood cells don't collapse and cause the bottom to shrink and split. Then you can let it slow dry, and afterwards coat it with a preservative. There are also a bunch of little critters, bacteria, that feed on the wood, so a little lysol solution can help kill them off. Dry rot is tougher, and to be honest, I'm not sure there's much you can do except maybe try filling and sealing. I'm no expert on palm wood - more used to conserving oak and pine species. I'll check with one of my conservator buddies and see if he has any suggestions.

amiotiki

T

Hey BK! That must hurt!

All kidding aside,

On 2006-03-02 20:48, amiotiki wrote:
Hiya Bullgator!

...I'm no expert on palm wood - more used to conserving oak and pine species. I'll check with one of my conservator buddies and see if he has any suggestions.

amiotiki

amiotiki! What a great resource! That's great information - thanks!

[ Edited by: tikigap 2006-03-02 21:09 ]

[ Edited by: tikigap 2006-03-02 21:09 ]

B

Thank you very much Amiotiki the wife is purty ticked off at my bro in law for not monitoring BK during his drying out phase. I'll just hold off for a while untill I hear back from you or one of the others. Thanks again for such a speedy response.

Glen L.

A

Hi again...

I checked with Dr. Brad and he suggests that you treat the wood the way we would treat pine - using sucrose as a bulking agent to shore up the cell walls. He even went so far as to suggest that all the wood that the carvers use be pretreated by bulking before carving even commences. This could be very helpful with rot issues in palm species - the water comes out, the sugar solution is anathema to critters (especially if you use a little lysol to keep bacteria down). I don't recommend bleach because of its caustic nature - it tends to degrade organics. If you're interested, I will write a longer and detailed post on how to do sucrose bulking...I promise it's not difficult or expensive. :)

amiotiki

T

I'd be interested in hearing how that's done. Just in case I ever needed the info. Please post!

A

Okey dokey...this is going to be a little long (I think). I'll try not to be too technical or get into too many of the scientific details. I'm going to start with some of the signs of trouble:
Face checking (FC), radial shrinkage (RS), tangential shrinkage (TS) and longitudinal shrinkage (LS). FC is a good sign that the wood has undergone cellular collapse, which is irreversible - the surface of the wood has sort of a checkerboard of cracking or crazing on it. RS and TS are responsible for the big cracks in logs that run outward from the heart of the wood and lengthwise. LS is primarily manifested as shortening - doesn't really cause any cracking.
All of these are caused by the collapse of the wood's cell walls when the water normally contained in them leaves too quickly. It's really important to remember that this is irreversible - the cells can't be plumped back up once they collapse.
So, the way we avoid the cellular collapse depends on what kind of wood we're working with. Some of you are probably working with dry, seasoned wood - while others are working with fairly fresh (green) wood that contains a lot of moisture. Either way, the wood should be bulked - probably before work begins, but certainly after a piece is finished if you want to keep it from cracking or deforming. Essentially, all bulking does is replace the water in the cell walls with something that will strengthen them during the dehydration process.
Equipment needed:
A vessel or tub large enough to hold your 'artifact'- agricultural feed troughs work great
Bubble wrap for insulation
A means to heat the solution in the tub to a top heat of 70 degrees C (158 degrees F) - waterbed heater, restaurant sink heater.
A solution circulating device - electric fish trolling motors (easily powered by a 10 amp battery charger)
Methodology:
There are two products that can be used for bulking - PEG or sucrose (plain old white sugar). Sucrose is the cheapest and easiest to acquire, and gives the best results as long as you follow the procedures that follow.

  1. If you're working with hardwood, start with a 10% solution of sugar to water; if softwood (palm is considered a softwood) use 5%. Weigh the wood first - this is important.
  2. Put solution and 'artifact'in tub, position the stirring device and heater, place bubble floating on the surface, and fire her up. There is one drawback to using sugar, and that is its tendency to ferment - nice for brewskis and other beverages - not nice for wood. To prevent runaway fermentation, which occurs when the sugar concentration is less than 40%, we apply heat. 50 degrees C generally controls the fermentation, but you can pasteurize the solution by heating it up to 70 degrees C for a few hours at a time, usually without harming the wood. If you can't get the temp up, you can use 100ml of Lysol per 50 liters of solution for several weeks until the 40% mark has been passed.
  3. Increasing the strength of the solution: If the 'artifact' weighs less than a few pounds, the percentage of sugar can be increased 10% per week until a concentration of 50% has been achieved. Once the 40% mark has been passed, the solution becomes hypotonic to organisms and they can no longer survive, so you don't need to worry about heat or Lysol anymore.
    If the 'artifact' is large, you may need to wait longer between increases - perhaps up to a month...but I think for most of y'alls purposes two weeks would be sufficient.
    NOTE: The gradual increase of sugar concentration is critical in order to minimize osmotic pressure differentials - in other words, to keep the exchange of water and sugar steady and consistent so cell walls don't collapse.
  4. Once you've achieved the 50% solution level, weigh the 'artifact' weekly until you see about a 20% increase in the weight. If the wood was missing a lot of cellulose before it went in the tank it could gain as much as 25-35% of its original weight.
  5. At this point the wood is ready for slow dehydration in a humidity chamber (I'll tell you how to make one of these at the end). Remove the 'artifact' from the tank and allow excess solution to drip into the tank. Slow drying in the humidity chamber (HC) reduces the possibility of osmotic collapse of the cells from drying too fast, and the adjustable humidity reduces stress on the different layers of the wood.
  6. Load your wood into the HC from the top down on a rack that will allow excess fluid to drip onto the floor of the chamber (for easier clean-up). Close the plastic curtain and turn on your humidifier - this should bring the relative humidity up to 100% pretty quickly. Shut off the humidifier. Check the artifacts every few days, spraying the inside of the HC with Lysol to eliminate the possibility of MOLD growth. After four - five weeks the ambient humidity in the chamber should be about 50%, and you can open it up to expose the wood to the atmosphere.
  7. You're going to want to keep the wood in a situation where the relative humidity is at 40-50% (typical of air-conditioned buildings). Otherwise there may be some shrinkage or expansion, but this shouldn't cause any significant damage to the wood (unless you're in like a 6% relative humidity part of the country, hehe).

To build a HC you just need some kind of container (a plastic agricultural tank with an opening in the side cut out and covered by a shower curtain works great), a rack for the inside, a humidifier - preferably that can be turned on from outside the HC, and that also has a gage indicating current humidity in the chamber.

While all of this is relatively cheap to build and easy to use, it does require patience. The whole process can take 3 - 6 months so you would have to plan ahead to prep your wood if you wanted to bulk it before carving, or the same amount of time if you do this after you carve. The payoff is that you'll have a very nice, stable piece of wood to work on that won't crack or split.

All of the above information is courtesy of Bradley Rodgers, PhD, in his book The Archaeologist's Manual for Conservation published 2004.

Best of luck to you all!

amiotiki

P.S. If you want to know how to remove stains from your wooden items, let me know and I'll post info about how to go about that.

B

Wow, who'd thought that I'd get so lucky as to have a restoration profesional answer a simple question. I LOVE THIS BOARD! Thanks amiotiki. You da man. The stain removal would also be of great assistance. Thanks again for your time.

Glen L.

T

On 2006-03-03 18:57, amiotiki wrote:
P.S. If you want to know how to remove stains from your wooden items, let me know and I'll post info about how to go about that.

Well, of course! That info could be very useful if posted here.

The other info was good too! Thanks for posting that.

What's your take on 'log end sealers', where you put the fresh cut ends of logs into some solution to prevent rapid dehydration. I think that is what the stuff does, but it would be cool the hear what's really going on there. What do they make that solution out of too? I'm planning on cutting down a few walnut trees (that are live now), and I'd like to prevent them from checking (RS - radial shrinkage). I have some stuff called Green Wood End Sealer. The container doesn't say what is in it.

Thanks!

8T

Tikigap, I have used that sealer on walnut and it is basically a liquid wax that you paint on. The moisture in it evaporates and leaves only the wax. Put it on quickly because it dries fast. If you are cutting live walnut and sealing the ends, my experience is that the log will stay wet inside for quite a while. But oh it carves so nicely!

A

On 2006-03-03 19:28, Bullgator wrote:
Wow, who'd thought that I'd get so lucky as to have a restoration profesional answer a simple question. I LOVE THIS BOARD! Thanks amiotiki. You da man. The stain removal would also be of great assistance. Thanks again for your time.

Glen L.

ROFLMAO...sorry - I'm da woman, hehe

I'm actually an archaeological conservator - my biggest job is to stabilize and conserve archaeo artifacts...restoration is a way bigger job. I wish I had that skill as I have some wonderful antiques pieces that could really use the attention of someone who knows how to do, for example, veneer work. My poor old Singer sewing machine cabinet has lost its top layer of laminated oak - so I just covered it up with an old indian blanket and put a plant on top.

Tikigap - I don't know anything about the green wood sealer stuff...sorry 'bout that. My only worry about it is that it prevents dehydration completely, which might lead to rot inside the wood - has to do with the cellular structure of wood cells and how moisture moves throughout the wood itself. Do they say anything about why you would want to use it?

Stain removal:
First of all, stains can be an indicator that the wood is under attack either chemically (such as from metal oxides), or from biological agents (mold, bacteria). Some stains may need to be removed before bulking because whatever it is that is causing the stain may be blocking the tiny openings called pits that allow the movement of air and water through the wood.
Black or brownish stains can be caused either by anaerobic breakdown of metals like copper or iron or by sulphides from organic substances. If the stain is from a metal the best way to remove it is with poultices made of citric acid (there are other acids, but they are toxic to use and citric acid actually does a fantastic job). Mix a 3% solution by weighing out 3 grams of citric acid crystals (you can find citric acid in the canning section of the grocery store)and adding it to 97 ml of distilled water. To make the poultice you can either soak cotton balls with the solution and carefully place them ONLY on the stain, or you can add talcum powder to the solution to make a paste that you can place directly on the stain.
The poultice will need to be changed several times (most likely) to remove the stain. When a satisfactory result has been obtained, you can squirt a buffering solution of baking soda in water on the treated area, then rinse completely with distilled, deionized, or rain water.
IMPORTANT: only treat the stain itself - do not immerse the wood in the solution because all acids are detrimental to wood and other organics.
Organic stains are neutralized with hydrogen peroxide, using the poultice method as above. The solution is 3-10% (3% is the strength you get in the drugstore or supermarket). You need to carefully monitor progress and stop if any indications of damage to the wood appear.
IMPORTANT: All stain treatments require meticulous rinsing, usually for several hours with frequent water changes - and as above, using distilled, deionized, or rain water.

As with the bulking info - all of this comes from Brad Rodgers book The Archaeologist's Manual for Conservation, published in 2004. Cited with permission.

amiotiki (Tina)

T

Thanks 8ft and Amiotiki!

Excellent explanation, Amiotiki (Tina)! Thanks!

The bottle of "Green Wood End Sealer" I have says it's a wax emulsion and non-toxic.
It says "Apply as soon as possible after cutting or end trimming to all end grain surfaces". I learned here (on TC) that it prevents checking/cracking/splitting and you let the wood rest for a long time (6+ months) before using (carving) it.

I don't really want to wait that long, but if it'll help make the piece last longer, it's worth it. I have the luxury of letting this newly cut wood sit for a long time, because there is other wood nearby that has already sat for a long time, (but it was never stacked for drying and end-trated like I thought I'd like to do with this new harvest - it's just rotting on the ground).

I'd like to know more about how to properly season walnut, like what chemical/natural treatments I can do to improve the performance of the wood, and how to stack it to aid the dehydration process, without (or with a minimum) of warping and insect infestation. Any suggestions would be greatly appreciated!


[ Edited by: tikigap 2006-03-03 21:14 ]

B

Excellent discussions and solutions to wood checking and rot isues. Very Informative. Thanks Amiotiki and Bullgator and everyone else who poster her.

B

Arrrrrrrrrrrrrrrgh thats the sound one makes after they remove their foot from their mouth. Said in a Southern Gentlemanly manner aka Rhett Butler, "Please accept my most humble apologies "MAM". GDR I don't know if'n I'll be able to do all that the Misses I think would have a 'kitten

P
pdrake posted on Sat, Mar 4, 2006 6:33 PM

what is humidity?

H

Great thread here bullgator-lotsa good iinfo! Especially since I'm drawn to rotten logs like white on rice.

what is humidity?

pdrake, to answer your ? about humidity---

'Hum' is a derivation from the latin word for 'human' and 'idity' is derived from the latin term for 'idiot'.
So- 'humidity' is the modern term for 'human idiot'. Humidity levels are directly associated with the amount of human idiots in one place at one time, ie., 60 % humidity would mean that there are slightly more human idiots in one place at the given time than there are regular humans.
I could be wrong so someone correct me please if so.

(just being silly pdrake-by no means am I assuming you're an idiot!!!!!!) :lol:

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