Kiln Drying NOT Good. Am I Right?

[redsquid2]

I just want to get some perspective on this. I am no expert, but I do a lot of searching on bf. The information I have found is that kiln dried wood has been "shocked" and is unstable. Just a hunch; if any natural material is dried so fast, it is going to be unstable.

What I have read is more like this: wood needs to dry slowly: that is why they put wax on the ends of it, even when it is air drying, to slow down the drying. 1 1/2 years of air drying. Dry a log for a year, then cut it into smaller pieces, and dry it another six months. THEN plane it/ sand it / stablize it.

Some of the ebay sellers will sell book matched sticks and say "kiln dried" right there on the auction page, as if "kiln dried" was a good thing.

 

[tattooedfreak]

Kiln dried isnt terrible (now the wood guys will shoot me) but I wouldnt use it until it sat in the shop for a few months.

 

[Rick Marchand]

I've got a piece of "baked oak" that is as tough as nails. Drills like steel, great to work with.

 

[Mahoney]

All wood is unstable if exposed to changes in moisture or humidity, whether it was kiln dried or air dried. Kiln or air dried wood that was kept in a climate controlled warehouse before it came into your shop where it's 90% humidity may warp. A piece of wood may have internal stresses due to reaction wood fibers and other reasons, cut it into smaller pieces and they may warp

There is no problem with properly kiln dried wood of any species.

It is also possible to ruin wood by kiln drying it, in various ways, some of which can be hidden below the surface. This is why it is a good idea to buy your wood from a reputable dealer who knows who and where the lumber is coming from, and will stand behind their product if there is a problem. But kiln defects from established lumber suppliers are pretty rare, the science behind drying lumber is fairly well worked out. It's the guy with the home-brew kiln in the back yard who may be another matter.

Coating the end grain of blocks and logs is done to prevent "checks" (splits). Wood drys faster through end grain than through the face of the board, or side of the log. As wood drys it shrinks and if the end of the log gets smaller, but just a couple of inches away the log is still wet and larger..., the stress will eventually be released when the wood cracks. This can ruin a lot of wood, so you try to slow down moisture loss through the end grain with wax, paint, etc.

 

[Alpha Knife Supply]

I just want to get some perspective on this. I am no expert, but I do a lot of searching on bf. The information I have found is that kiln dried wood has been "shocked" and is unstable. Just a hunch; if any natural material is dried so fast, it is going to be unstable.

What I have read is more like this: wood needs to dry slowly: that is why they put wax on the ends of it, even when it is air drying, to slow down the drying. 1 1/2 years of air drying. Dry a log for a year, then cut it into smaller pieces, and dry it another six months. THEN plane it/ sand it / stablize it.

Some of the ebay sellers will sell book matched sticks and say "kiln dried" right there on the auction page, as if "kiln dried" was a good thing.

1) Drying wood in a kiln is not fast or slow. The biggest factor in the rate of drying is the wood species. Big leaf maple can dry in a few weeks. Snakewood takes a few years.

2) Wood is not "shocked" and/or "unstable" when kiln dried. Wood that has been properly dried in a kiln is extremely stable. This is why kiln dried wood is popular in cabinet and furniture making.

3) Don't buy wood on eBay. There are lots of wood sellers on eBay, but what do you know about them? For example:

- a) What kind of kiln? Is it a cardboard box with a lightbulb or is the kiln temperature & humidity controlled with limit switches to shut down the kiln if it gets too hot or too dry?

- b) Who stabilized the wood?

- c) What is the stabiliant?

- d) What was the moisture content of the wood before it was stabilized?

- e) How much time elapsed between drying and stabilizing?

Call Mark at Burl Source. He has correct answers to all these questions.

4) You misunderstood the reason for waxing the ends of logs & blocks. PMMahoney posted an excellent response.

Properly kiln dried wood is a good thing.

One final thought. Why buy from eBay? The only reason I can think of is to save money. I've never understood the desire to save a few pennies and risk quality. Custom knives are supposed to be higher quality than factory knives. Why risk a having a dissatisfied customer to save an tiny amount of money?

Chuck

 

[mete]

Yes, Chuck drying is a science . Each type of wood is different and requires a different schedule to dry . Type ,size ,moisture content ,ambiant temperature and moisture. I've seen many an amateur stockmaker cut down a tree and send a stock blank piece to a kiln and came back with a warped piece of wood !! Easy, just put a 2" thick piece in with a load of 1" flooring !

 

[Burl Source]

Good points from Tattooed freak, Mahoney, Chuck and Mete.
Not much I can add to their answers.
Done properly = good, with both air and kiln drying.

 

[redsquid2]

Why buy from eBay? The only reason I can think of is to save money. I've never understood the desire to save a few pennies and risk quality. Custom knives are supposed to be higher quality than factory knives. Why risk a having a dissatisfied customer to save an tiny amount of money?
Chuck

I buy from ebay because of other reputable sellers just like me. I have been buying and selling on ebay for about 11 years, with no problems. I don't understand peoples' assumption that buying on ebay means risking quality. I think they just don't know how to interpret feedback.

 

[Smithy]

Can a food dehydrator work on small slabs of wood to dry is sufficiently for stabilization?

 

[redsquid2]

Thanks for all the replies.

 

[jdm61]

Just to put this in perspective, the Gibson solid body electric guitars of 1950's like the Les Paul model, some of which sell for hundreds of thousands of dollars today, had their wood dried in "kilns" that left "puddles" of hot resin/sap in the floor of the kiln. Those guitars are known for the EXTREMELY high quality of their tone woods. One of the differences between those and most sold today? The quality of the raw materials they started with. Better wood.Soem argue that they get better as time wear on because the woo continues to dry for decades after the instrument was made, but these things were great the day they left the factory. The "secret stashes" of older no longer available tone woods like Adirondack spruce and real (not wood from old stumps) Brazilian rosewood that companies like Martin, Santa Cruz, etc have for their top of the line custom shop pieces and charge thousands of dollars just for the wood upgrade are desirbable not just because they have been sitting around drying for 50-70 years, but because they are Adirondack spruce and Brazilian rosewood.

 

[redsquid2]

Just to put this in perspective, the Gibson solid body electric guitars of 1950's like the Les Paul model, some of which sell for hundreds of thousands of dollars today, had their wood dried in "kilns" that left "puddles" of hot resin/sap in the floor of the kiln. Those guitars are known for the EXTREMELY high quality of their tone woods. One of the differences between those and most sold today? The quality of the raw materials they started with. Better wood.Soem argue that they get better as time wear on because the woo continues to dry for decades after the instrument was made, but these things were great the day they left the factory. The "secret stashes" of older no longer available tone woods like Adirondack spruce and real (not wood from old stumps) Brazilian rosewood that companies like Martin, Santa Cruz, etc have for their top of the line custom shop pieces and charge thousands of dollars just for the wood upgrade are desirbable not just because they have been sitting around drying for 50-70 years, but because they are Adirondack spruce and Brazilian rosewood.

Interesting.

I pulled some maple shelving out of a dumpster a few years ago. Based on the building it came out of, I am pretty sure it was installed ca. 1961. I have made a few hidden tang knives with it, and it is very nice to work with. Not the most outstanding grain/figure, but very solid. I need to take inventory of how much I have left.