View Full Version : Dehumidifier Question

Steve vanPelt
11-27-2009, 12:43 PM
Thought I could spend the next four months making jigs and sweeping, but now I can see that's not going to happen. It's raining and 100% humidity and I don't want to make any more potato chips like what happened in the spring, so I'm going to have to dehumidify the shop.

I've been researching dehumidifiers the last couple of days, and I'm finding high capacity residential models at one price point, and low capacity commercial models for 4 to 10 times as much. I'm guessing that the difference is durability and lifespan of the unit.

So for those of you that dehumidify your shops
what kind of unit do you use?:confused:
how do you filter the incoming air, and:confused:
what else do I need to know to help choose the right unit?:confused:

Thanks, Steve

11-29-2009, 05:32 PM
Hey Steve, here is what I do. Right now, my house and shop are undergoing a major remodel and there is no way to currently close up the shop. Therefore, I am dehumidifying a spare bathroom across from my shop. I move the resawn wood into the bathroom some weeks before starting to use it. I work on the instruments in the shop and put them back in the bathroom when done. A small residential unit works very well for this. I'm on the Oregon coast, most of the time the humidity in my house is between 65 and 50%. I keep the bathroom at about 45%. Dehumidifiers are fairly simple and sturdy devices, I am on my second one in over 24 years of building.


Steve vanPelt
11-29-2009, 09:35 PM
Thanks, Bradford, think I'm going to order one this week. Most of my wood is in our bedroom closet already. What scares me is that I've watched tops and backs curl while working on them when it's raining, so I really want to dry up the shop some and keep it consistent. Thanks again, Steve

11-30-2009, 12:42 AM
I have a tiny 7foot by 7 foot workshop, that has a mini oil filled heater and a domestic dehumidifier, I use a digital humidity/temperature monitor to make sure things stay dry, ideally 43% at 21degrees Celsius, I have another digital monitor in my house for when I sometimes work indoors(more often when setting up, or french polishing)

In such a small space I can have the workshop at the right humidity in an hour, In my old 35 foot shop it would take a morning. Sometimes I use a bowl of water to increase humidity.

My First winter working fulltime as an instrument maker(2002/3) I struggled to keep the temperature warm enough for the titebond glue to dry, my shop was a converted barn though but you can see the problem is not just humidity!!! each space has its issues

I have a microclene air filter, to catch the ambient fine dust, plus a dust extractor to attach to the bandsaw/planer/sander

Moore Bettah Ukuleles
11-30-2009, 07:44 AM
Because I run my shop off of solar photovolteics I need to watch my energy usage. The daily ambient humidity here ranges between 65% and 85%, pretty high. I have a small building room isolated from the general wood shop, where all the gluing and assembly takes place. I maintain this at an RH of between 45% and 50%. A small 6000 BTU air conditioner does most of the work in maintaining the temperature and RH I want during the day. I also have a Sears room dehumidifier which I occassionally run but it tends to heat up the room considerably. I'll run it when the room is too cold. The AC does a much faster job of extracting moisture from the room. Since I can't run equipment at night (no sun remember?) I also have a dry box, about the size of a refrigerator where I hang all work in progress during the night. The dry box is dehumidified by means of two 45 watt mini dehumidifiers (Ace hardware). All my precut wood sets for my next building cycle are also kept in this "box" for several weeks. A light bulb burning 24/7 would be similarly effective.
I need to mention that as I was building this room I installed plastic sheeting on the walls under the sheet rock to act as a vapor barrier. The concrete floor was also sealed against moisture intrusion.

Steve vanPelt
12-02-2009, 07:52 AM
Thanks, Mike and Chuck, appreciate the pointers. My shop is solar powered, too....skylights. We actually do generate all of our own electricity with a PV system, butwe're grid tied so we don't have to worry about batteries, or night, the meter just runs backwards during the day and we catch up at night.

Yesterday I pulled the trigger and ordered a Danby 70 pint unit, should be here in a week or so. My shop is set up in the corner of a pretty big steel building and I hope the unit will suffice. If not, I can repurpose the old 8X10 chicken coop for a build room.

I keep some wood in an old large file cabinet and I'll get a shop light to put in the bottom drawer. Thanks for the tip. I've received a 'request' to move the closet wood back to the shop 'where it belongs' so I better get a light soon.

In the pic below is what happened over one rainy night last spring. Wanna try and avoid that happening again.

Thanks again to Bradford, Mike and Chuck for the info to help me get back to the shop before April.