Condensation cure?

[Roger Pozzi]

My shop is now in a 10'X16' wooden shed. NO insulation. But I only use my shop sporadically, like maybe twice a week in the winter. I heat it with a Big Buddy propane heater which does a fantastic job and I only try to keep it around 55 or so when I'm in there. Not a problem with that.
My problem is that when I go to the shop, condensation appears everywhere. As far as I know, this is caused by the tools being a lower temperature than the air. Is that right?
Is there a low cost way to prevent this problem? Am I doomed for the season?

[Robert Payne]

Roger,

All of the metal items in your shop (especially those with substantial mass like a table saw or jointer or bandsaw) retain their cold temperature much longer than the air when you warm your shop to a tolerable temperature. As a result, those items will capture moisture that condenses from the warmer air and you'll get rust on them if you do not take preventative measures. An open heat source like a ventless propane or a kerosene heater will add more moisture through combustion as well. Use an electric heater whenever possible since it will not introduce moisture.

Solutions? One option is to keep the space warmer, but that is costly in an non-insulated shed. I'd suggest you coat the exposed cast iron surfaces with a rust preventative (either a commercial product like T-9 Boeshield or a home brew like paraffin mixed 50:50 in warmed mineral spirits). In addition, cover all of thoe metal surfaces with oilcloth or canvas covers while you warm the shop enough to bring some heat to that metal to room temperature. If possible heat the tools up before heating the air space. No easy solutions since moisture in the air will undoubtedly condense on cold surfaces.

To be honest, you are fighting an uphill battle, but remember to protect the tools first.

[Roger Pozzi]

Rob,
Thank you for your reply.
Did you possibly mean that by using a vented propane heater, the problem could be reduced? Or, is it just because of the open flame (although I don't think of it as open flame with the ceramic plates)?

[Robert Payne]

Roger,

If their is not a flue to exhaust the combustion gases, they will be released into the work space, meaning that includes water vapor and increased humidity. Most ceramic propane heaters I have seen are unvented and therefore will release the moisture into the shop space. If you have an adequate power source, an electric space heater will not release moisture as you heat the space.

[John M. Smith]

I used an unvented propane heater when I finished out the interior of my shop. I literally had water running down the walls from all the vapor it put out. I would definately go to a vented unit if I were using it all the time. Think of your house furnace. They don't put that much moisture in the air.

[Jim Andrew]

When I kept a table saw in my unheated garage, it was always rusty when I went to use it. Have tried Boeshield, but found it lacking. The idea of parafin mixed with paint thinner, is a good idea, as it would become a coating of thin parafin, as after the paint thinner evaporates, you would have a thin coat of parafin on the machine top. I tried mixing it once, put a block of parafin in a pan on the stove, and warmed it to a liquid state, and then just poured it into the paint thinner which was at room temperature. It stirred right up, and stayed clear. I mixed linseed oil in it and used it to seal the inside of a wood garage door. Seemed to seal the wood well.

[Roger Pozzi]

Thanks to all.
I think the most affordable option is to stay in the house and plan projects and get supplies ready for better weather conditions. According to almanacs and highly trained (??) weather forecasters, I may only have to wait 2 to 2 1/2 months. And, whenever the temps are good enough, I can sneak out for a little while. After all, I live in Ohio, waiting for weather changes may only be a matter of hours.