Humidty and Temp control workshop to prevent twisting/cupping etc.
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- This topic has 3 replies, 3 voices, and was last updated 10 years, 1 month ago by Kevin Bowkett.
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30 March 2014 at 7:19 pm #41860
Hi there, I need some advice and guidance on how to maintain temp and humidity within my newly built shed/workshop. Or at least, I think that’s what I need.
Symptom : Piece of 22mm thick pine, planned flat and square last week has twisted and cupped. 🙁
I left it on my workbench which is placed directly in front of the double glazed windows. Today, I went up there to do a little bit more work on the bookcase, but found that the piece of wood had cupped and twisted.
I have a hygrometer which reads between 50 and 65% – so I know its pushing high – during the waking hours (I’ve not taken a reading late at night or really early in the morning yet). I have a heater with a thermostate keeping it at about 6 degrees C (on the cold side). This afternoon, its was 22 thanks to the lovely sunny day.
I’m looking to maintain a stable humidity and temperature. Unfortunately, my windows do not have vents, and leaving them open creates too much of a gap. The building is timber frame, with pine shiplap on the outside. It has a membrane and some insulation in the wall, ceiling and floor cavities. It is tongue and groove pine lined.
I suspect I need to put a vent in to help circulate the air, perhaps even a dehumidifier. However, I’d like some advice from people who have experienced this or more knowledge on the topic than myself.
My first question would be how long did you let the wood aclimate before you first processsed it? The second would be how dry was it to start? Wood dries from the outside in, so when you plane the surface you are removing the most dried part. Leaving it flat on the bench top effectively sealed the bottom side. When the sun hit the top this accelerated the drying process.
I would suggest giving the wood a couple days on stickers out of the sun and see if some of the cupping and twist does not resolve itself.Kevin,
What Michael said.
If you want to accelerate the process you can steam the cup out by
laying a wet cloth(old ‘T” shirt material) thoroughly wrung out on the board cupped side and run a hot iron (borrowed from your significant other secretly 🙂 ) over the cloth effectively “steaming” out the cup.
Stop when the board straightens out ,sticker and weight down and let it dry.
Best,
Craig2 April 2014 at 10:46 pm #46386The wood had been stored in the same building for about 4 weeks but I’m not sure how dry it was to start with.
Thanks for the comments, I’ll give them a go and see what happens.
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