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Joined: Aug 30, 2005
Posts: 125
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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)
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