Work shop Humidity

[Sean Boyle]

I was reading an old post

" In Texas, heck you need massive a/c. In northern Minnesota, you need a blast furnace and bars for summer to prevent the mosquitos from taking you away! In parts of Arizona, you need a swamp cooler to add humidity for a big part of the year plus a/c all year long. Florida's the opposite, gotta PULL humidity all most all year long."

My Question How Important is work shop humidity. I live in Northern Ontario and and my 16 x 24 woork shop is heated by a pellet stove the air does not get any drier. Secondly does humidity affect your turning

 

[Thomas Stegall]

The importance of humidity will be dependent on a few factors. If you turn kiln dryed wood than a low humidity shop will keep the wood stable. If you turn mostly green wood as I do, then shop humidity can play a huge role. The other factor for green wood equally is air movement. Even with humidity that is between both extremes, air movement can accelerate drying of green wood. Make sure you store your wood out of direct sunlight and protected from a lot of air movement. Additionally, the type of wood you use will to some degree determine the impact of humidity. Some woods like Oak have a very open grain structure and endgrain will absorb moisture or dry extremely fast as a result. Some woods have checks that travel far down the wood once they start (walnut as an example) where other woods can develop huge cracks that only travel an inch or two. If you turn alot of green wood, I would suggest not disposing of the shavings until after they have given up there moisture to your shop. I would also look into keeping a large pot of water on top of your pellet stove so that when it heats up it will add moisture to the air in your shop.

 

[David Wilkins]

I'm in Nova Scotia, yes, humidity will affect your turning. If you bring in wood now, it'll go from frozen water to the dry environment, drawing water out fairly quickly, causing it to check. If you waxed the ends before things froze, the freezing probably pushed the wax out of the pores and it would need to be re-coated. When I rough turn and set to dry it's best if I can leave the item for a year, I know turners in Edmonton who have to wait six weeks and yes, Arizona turners can get away with a two week drying time.

What you have to remember is the wood has to dry evenly, regardless of the pace.

 

[Syd Sellers]

Humidity Control

I agree, I'm in Alberta. In the winter time the RH is down around 10-15% in Summer with the thunder storms, RH is very hi.

I turn a lot of items that are made up of several pieces that fit together. If I don't control the shop, one day everything is loose and works fine, next day everything is seized up.

Also if I ship an item to Vancouver (Rainy Vancouver) I have to make sure every surface is sealed very well. If not, it will warp and change shape a lot

 

[MichaelMouse]

My Question How Important is work shop humidity. I live in Northern Ontario and and my 16 x 24 woork shop is heated by a pellet stove the air does not get any drier. Secondly does humidity affect your turning

Get a hygrometer. You don't need to guess at the relative humidity, for about $10 you can see what it is.

What it does for wood is pretty well covered here. http://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr190/chapter_04.pdf If the moisture content gradient is too steep, the wood surface will dry too fast, trying to shrink around an expanded damp interior, possibly causing stress checks as the wood contracts. These can quickly find a plane of weakness and lead to a full crack. It's difference that destroys, so wood previously brought down to a lesser moisture will lose more gracefully. Makes no practical difference if the wood was ever in a kiln.

Low relative humidity can also adversely affect the turner. http://www.infoplease.com/ipa/A0001433.html

 

[Barry Elder]

Naturally, along with the moisture in the wood you are likely to use, it depends on where you are on the planet. Down here the relative humidity is such that my green wood gets close to the average humidity pretty quickly, so my shop is open (overhead door). If you are frozen up and keep your shop levels controlled, I would think it would be like flipping a coin!

 

[robo hippy]

Sean,
If you bring in a frozen piece in winter, and the shop is warm and dry, the wood will want to dry out way too fast, and mostly turn into toothpicks. Plastic bag it till thawed, then turn it down, and re bag it. Should be okay. Summer time, not much of a problem.

Any where near Kenora? I fly out of there every summer with dad and brothers to a conservation lake for walleye and northern. Nice country, but not much in the way of trees.

robo hippy

 

[MichaelMouse]

Sean,
If you bring in a frozen piece in winter, and the shop is warm and dry, the wood will want to dry out way too fast, and mostly turn into toothpicks. Plastic bag it till thawed, then turn it down, and re bag it.

Thaw? THAW? A real man turns as is, even when there's ice or snow on it. So what if it's like shooting chipped ice rather than soft wood down the flute into your knuckles.

Helps to have some warm water for that off hand, though. Can get cold. And remember to wipe the ice and melt off the bandsaw table.

 

[Bill Boehme]

What's all this talk about ice and frozen. The grass is green, trees are blooming, birds are building nests. I turned some wood in the middle of winter when the temperature was around 60° F -- it didn't seem any different that when turning at 112° F last summer except for not sweating.

 

[dbonertz]

Thems fighten words Bill.

 

[Sean Boyle]

I would like to thank everybody for their feedback

I picked up a hydrometer today and sitting at 22% RH and what is ideal.

 

[Sean Boyle]

Sorry Walter if I was paying attention I would have notice 55%

next step fiquiring how to get there I cant boil water on top of the pellet stove as it does not get hot enough on top all the heat is out the front so I am going to try a dry mist vaporiser. I have one available to try.

 

[MichaelMouse]

Sorry Walter if I was paying attention I would have notice 55%

next step fiquiring how to get there I cant boil water on top of the pellet stove as it does not get hot enough on top all the heat is out the front so I am going to try a dry mist vaporiser. I have one available to try.

Water does not have to boil to evaporate. Put a pan on top of the stove and you'll raise the RH to a friendly 45 % which will keep the wood at about 8.5 percent at 20C.

If you have one of those heat recovery fans in the pipe, set the pan in front of that.