Do I need to strip the wax from my wood for it to season properly?

Nathan the Machinist

Nathan the Machinist

KnifeMaker / Machinist / Evil Genius
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Every year I buy wood for future years so it can age a few years before I use it. Used to be, the wood would usually have a sealant on the ends to keep it from drying too fast. But this year the wood came totally sealed in wax. African Blackwood, Cocobolo and Osage Orange. In theory the wood is already dried and won't move much in the future, but I don't think this is really true so I prefer to age it.

Given this wood is going to sit several years before I use it, will moisture still pass through the wax over time or do I need to strip it for the wood to season properly?
 
As a woodworker I've been taught the the end grain looses moisture at a much faster rate than the side of the grain. If it were mine the way you've described and not knowing absolutely for sure if it's thoroughly dried through and through, it could be "case hardened" with the core more moist than the surface, I would strip all the wax off the wood and reseal just the end grain. This helps to even out the rate of moisture loss through the end grain and the side of the grain and helps to prevent cracks in the end grain.
 
woodwrkr221 said:
As a woodworker I've been taught the the end grain looses moisture at a much faster rate than the side of the grain. If it were mine the way you've described and not knowing absolutely for sure if it's thoroughly dried through and through, it could be "case hardened" with the core more moist than the surface, I would strip all the wax off the wood and reseal just the end grain. This helps to even out the rate of moisture loss through the end grain and the side of the grain and helps to prevent cracks in the end grain.
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Depending on what a moisture meter indicates, this is too dramatic a change and will result in checking IMO. Had a load of ebony blow up on me back in the 80's so have a bit of experience here.
 
Consistency of ambient humidity and temperature in your storage area is a major factor, moisture meter sounds like a good first step. I would consider calling your supplier and asking some questions.
 
If you are going to leave it age for a couple years, leave the wax on.
 
lotta times where i live it'll be 90% humidity and 95 degrees in summer and sub-zero in winter with attendant lack of moisture. I've found scraping off the sealant from the long grain only works best for me, especially for pieces that i'm storing for future use-much less cracking and checking on the end grain. of the three you listed it's been my experience that the osage orange tends to crack and fracture the worst( ya know be the chippiest). it grows wild here and farmers cut it down as a nusience tree, generally. makes great fence posts-seen some more than 100 yrs old,supposedly. if it is the south american variety i can't speak to that. probably some local exotic wood suppliers could give you the best long term storage suggestions for your area. there are some well known ones in your area(NC). much luck,Neal
 
There is a lot of confusion about what the wax does. Im sure Mark will come in and save the day, but from working with exotic woods for a long time this is what I was taught.

Wood moisture moves out of the end grain orders of magnitude faster than it does out of side grain, and wood shrinks and expands perpendicular to the grain which means as wood dries it can pull itself apart. The goal of drying wood is to have the whole piece contract at the same rate so no cracks or shakes occur in the wood. In theroy, you probably only need to wax the ends, but the whole wood is often waxed for two reasons. A, paraffin is cheap and its eaiser to dip a whole bunch of pieces in at once than to individually dip only the ends in and B, it does add some layer of protection.

Wood is shipped over from the countries it is harvested in coated in wax to make sure the product does not crack during the drying from shipping. Many woods are dry to use when they are bought however. There is no way of knowing "without a moisture meter" how long the wood was out before it came into your possession. The Cocobolo for one is probably dry. It would be quite difficult to bring more into the country given the cites ban, and even it was a tad fresh Coco is a particularly stable wood. Blackwood can be a tad trickier to dry, so with that one i would leave the ends waxed and you should be fine stripping the sides if you are going to keep it inside where the temp and humidity are rather stable, you could probably strip off the sides more safely. The osage i wont comment on as i have never used it.
 
Nathan the Machinist said:
Every year I buy wood for future years so it can age a few years before I use it.
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May I ask why this is done? Is it significantly cheaper to buy your own wood and process it? Let's say purchasing 2 scales now ready to go are $20

I'm curious what the advantages are of buying, sawing, holding, processing your own wood is?

Thanks
 
I've been making pool cues from exotic wood for about 10 years. Usually the wood that is totally cased in wax is still wet. I would scrape the side wax off and leave the end grain sealed so it dries very slow. I buy most of my wood dry but once in a while I'll get wet pieces and let them sit for a couple years before I even consider using them.
 
wdwrkr221, Greenburg Woods, and drew1972 nailed it regarding the sealing of the end grain. As mentioned. it slows the drying process to help prevent checking. If you are cutting your own green wood, do not include the pith in the piece or you greatly increase the chance of checking unless it is monkey puzzle. If the wood is grained (not burl) my suggestion is to rift saw it rather than flat saw it. This will help the wood to not warp as it expands and contracts.
Seal the end grain with anchorseal.
If you want to accelerate the drying process, you can soak the piece in alcohol for a day, and let it dry in a brown paper bag for a couple weeks. check with your moisture meter. You can google this process online or check the wood turning sites for more detail on it.
 
I scrape it off the sides with a scraper. Don't try and sand it off.



People regularly confuse the moisture content in the wood with the humidity in the air.

Moisture content is the actual percentage of water in the wood. If a block has 10% moisture and weighs 10 ounces, it has one ounce of water in it.

Humidity is stated in Relative Humidity - the vapor pressure ratio of the amount of moisture present (partial pressure) to the maximum amount that can be contained in the air at that temperature ( equilibrium pressure). If the relative humidity is 10%, there is virtually no water in the air. At 99%, it has virtually all the moisture that the air can hold without rain/fog/snow/etc.

Wood will dry slower of faster depending on the humidity level present, but it will slowly dry to a quite low moisture content regardless of the humidity. I read people saying, "It is normally 90% humidity here. My wood will never get to 10% moisture content."
 
i have tried the paper bag method with some turning stock, with as i recall pretty nice success. Johnathans ; what no love? i mentioned it too:sorrow::D
 
hsc3_90293 said:
May I ask why this is done? Is it significantly cheaper to buy your own wood and process it? Let's say purchasing 2 scales now ready to go are $20

I'm curious what the advantages are of buying, sawing, holding, processing your own wood is?

Thanks
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But are they really "ready to go"? I don't want to run wood I just received, it's better to age it in my experience.

Also, when I'm done machining a set of scales they're ready to install, there isn't much finishing after installation. So I'll hang them where they see some sun so their color can develop before I use them on a knife. If the wood isn't well aged before running it there will be some movement while it airs out.

This is a quirk of my process. It does better with older wood, so I age it. I ran out of 2005-2008 stocks quickly because I wasn't making many knives back then and I didn't have many materials. I'm running out of 2009 stock now so the wood I'm getting into now is 5 years on my shelf. This is plenty of time I think. Half that would be fine. But I'm trying to stay ahead of the curve, so I order more wood every year to replenish my stock. And this last batch came in fully coated and I'm concerned it won't season right so I'm asking.

I don't run wood much, it's finicky, so I only process about 20-30 pounds a year, so that's all I'm talking about here. I run quite a bit of micarta though.
 
Stacy E. Apelt - Bladesmith said:
I scrape it off the sides with a scraper. Don't try and sand it off.



People regularly confuse the moisture content in the wood with the humidity in the air.

Moisture content is the actual percentage of water in the wood. If a block has 10% moisture and weighs 10 ounces, it has one ounce of water in it.

Humidity is stated in Relative Humidity - the vapor pressure ratio of the amount of moisture present (partial pressure) to the maximum amount that can be contained in the air at that temperature ( equilibrium pressure). If the relative humidity is 10%, there is virtually no water in the air. At 99%, it has virtually all the moisture that the air can hold without rain/fog/snow/etc.

Wood will dry slower of faster depending on the humidity level present, but it will slowly dry to a quite low moisture content regardless of the humidity. I read people saying, "It is normally 90% humidity here. My wood will never get to 10% moisture content."
Click to expand...

I would talk to your supplier and ask what moisture content is when he ships it. Also having a moisture meter really helps. If your wood is already around 9-12% I would guess you are about as dry as it is going to get. Not sure how wax affects color change and all that though.

What is "normal" moisture content for a "dried" piece of wood is relative to your area. I live on the Wet Coast and 12% is about what you will get here. Move to the prairies and dry will be around 9%. I bought a ryobi moisture meter that attaches to my cell phone. Has prongs which put small holes in your wood but it was $30ish and gave readings that were very close to my friends very expensive meter.
https://www.ryobitools.com/phoneworks/moisture-meter

What Stacy says about scraping wax off instead of sanding is good advice. I just used my belt sander to remove the wax on some Zircote and I have gummed up my 42" belt and can't get the wax off it! Dang I wish I saw this post two days ago!
 
Nathan,'Not to question your process as your work is something I aspire to, but why not use stabilzed wood, to eliminate all the problems associated with wood movement?
Sorry, Neal, my bad!
 
Greenberg Woods said:
Use a rubber sanding stick. If you dont have one of those, try running the belt on the bottem of an old tennis shoe. Any bit of rubber will take the wax off the belts.
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I have a rubber sanding stick...works great when it is clogged with wood etc...but doesn't seem to be taking any of the wax off at all. I was thinking of either freezing the belt to get the wax more brittle and try and if that didn't work I was thinking of heating it up and trying.
Randy
 
Stacy E. Apelt - Bladesmith said:
Wood will dry slower of faster depending on the humidity level present, but it will slowly dry to a quite low moisture content regardless of the humidity. I read people saying, "It is normally 90% humidity here. My wood will never get to 10% moisture content."
Click to expand...

Not true. The real deal from USFS data. Check the chart for air dried wood moisture content relative to ambient humidity and air temp. It's referred to as EMC

Sorry, forgot to add link to chart: http://www.csgnetwork.com/emctablecalc.html
 
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Stacy E. Apelt - Bladesmith said:
but it will slowly dry to a quite low moisture content regardless of the humidity. I read people saying, "It is normally 90% humidity here. My wood will never get to 10% moisture content."
Click to expand...

I agree with Larry , this is not true. The moisture content of wood is a direct result of the environment that it is kept in. Wood that is stored in 90% humidity will never ever reach 8% moisture no matter how many years you keep it there. If I take a piece of kiln dried wood that is 8% moisture and put it in an outdoor shed in my yard it will change from 8% to about 12% because the average humidity here is 65%. I can leave the wood in the shed 50 years and it will stay at 12%. If I want it back at 8% I will HAVE to put it in an environment that is 40-45% humidity.


Nathan I would scrape the wax off of the sides now and come spring time I would scrape it off of the end grain. I would keep a close eye on it after I scraped the end grain and if it starts cracking I would recoat it and give it a couple more years.
 
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