View Full Version : Metal condensation, Sweat? Moisture in unheated shop

12-07-2004, 05:27 PM
I got to the shop this morning, everything out there metal was covered in dew. It has been raining like a monsoon for days. NOW? It seems warmer today and everything is covered in water.

THE chips I left on the mill table were red.

Not really happy, How do I fix it other than heat the shop full time? Run the air conditioner?

My poor machines. I installed two of the chinese scales today in a box too. Literature said "non-condensing atmosphere" A small light bulb in electrical cabinets I think is in order.

I saw this last year but not as bad as this morning. I think it was springtime? Not sure.


12-07-2004, 05:28 PM
I heard it before, before you chime in.. A drop of sweat off a electrician will cure cancer.. so they say..

Ha.. David

12-07-2004, 05:35 PM
Anytime the metal is colder than the dewpoint you will have condensation. If the atmosphere is saturated that means colder than the air temperature. Problem around here especially this time of year is it is too dry. Never see any rust.

12-07-2004, 05:40 PM
We're getting some of that balmy weather up here in NC now. I have an oil bath radiator plugged in and going full time between my lathe and my shaper. It keeps the ambient temp between the two just warm enough and dry enough that I haven't had any condensation - yet. I had more problems with rust during the summer time.

12-07-2004, 05:41 PM
Actually Boo Boo it's 'a drop of sweat from an electrician will 'cause' cancer. Squirt everything with oil and call me in the morning.

[This message has been edited by topct (edited 12-07-2004).]

12-07-2004, 05:56 PM
Buy a dehumidifyer or two from wally-world. Pipe the drain outside so ya don't have to keep dumping the bucket. If the bucket isn't emptied and it fills up, the unit cuts off.

That's the cheapest way. If you want hi tech I can hook you up with a CargoCare system. Emcore has several here under contract that is keeping propellant loading rooms at 12% humidity right now as it rains outside. For about 25K http://bbs.homeshopmachinist.net//smile.gif


12-07-2004, 06:18 PM
ummm I think not http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif
Dehumidifiers are costly to run.
Or you can make your self an Epsilonifier that costs almost nothing to biuld and almost nothing to run.
1. find yourself a radiator matrex...from car
2. set it up with a fan behind it ..lets say 25 watt fan.
3 Site it at the highest point in your workshop ...because thats where the hottest air is and the hottest air also contains more moisture ...
Also the greater the difference between hot and cold will cause more condensate
4.Pipe mains water into it , and have the water piped out of the return down a drain at say 2 gallons an hour.
catch condensatrion off it and divert down the same drain.
Run it 24/7 and your problems are over
there you have it .
but if your on a water meter forget it.
OR if you dont like pouring 48 gallons of water down the drain a day forget it.
Disclamer.....it wasnt me 'onest guv
all the best...mark

12-07-2004, 06:50 PM
<font face="Verdana, Arial" size="2">Originally posted by aboard_epsilon:
ummm I think not http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif
Dehumidifiers are costly to run.

Not as costly as replacing machinery! I run
a dehumidifier, works great. I can't tell
any difference in the electric bill. It was
always high. The welders eat up the juice
more than anything.

12-07-2004, 07:15 PM
Have to heat mine 24/7

I use Rig rust preventative. Works great for me even outside for a few days.

I get it from Brownells

www.brownells.com/aspx/NS/store/search.aspx?k=rust&pc=10&ck=0 (http://www.brownells.com/aspx/NS/store/search.aspx?k=rust&pc=10&ck=0)

[This message has been edited by Tinker2 (edited 12-07-2004).]

12-07-2004, 07:19 PM
The crystal type kitty litter works for small ar eas, it's silica gel/ I have a small heater running at the moment in my garage.


12-07-2004, 07:44 PM
Big dehumidifier and pipe it outside just like noted above. I have done this and it works great. I do turn the thing off when I'm in the shop. Drives me nuts to hear it turn on and off while I'm working. I also use LPS when I'm not going to use the equipment for a while. But if I'm due back out in the shop within the next week, I dont bother with LPS.

12-07-2004, 08:05 PM
I been a thinking all day.
Not came up with a solution yet. (all the time I was mounting and wiring controls) I found a back plate from a old hoffman enclosure. No box, just a backplate. I'll have to box it in. Mounted Drive, pwr supplies, two opto22 racks, two chinese scales, relay to switch between them. Now I am documenting, reading manuals on doing point to points. And Watching Spiderman2.

I was thinking covers for the machines and a light bulb under them. And thinking something to kick on the ac during times of condensing atmosphere. Just like my doggie's house. Keep it warm and snuggly.

EVAN? Will a hard drive work in below freezing temperatures? I had one years ago that would not boot till it warmed up. I have not tried yet with it really cold out there.


12-07-2004, 08:13 PM
High dollar units do a nitrogen purge on all cabinets, they have a heater plate in the bottom of the panels too. There is a lot of mass there to heat. THE swing is why they condense? correct? Something to slow the swing of temps?

That was at Olin Chemical? Chlorine atmosphere.

Ain't nothing like memories. Even bad ones.


12-07-2004, 08:24 PM
My little wrought shop in my garage, no machines but bending gear and jigs, cutoff saw, drill press, a few hand tools, and a small torch for heating metal to bend. Yeah, I wish it only got cold enough to make dew, for now i have frost on everything from now until probably April.

Moisture rid buckets, and bar and chain oil. Works for me. I coat my machines with "Bowling alley wax" a few times a year by habit for this prevents dust issues (my garage is dirt floor), and so far has helped with the rust issues.

12-07-2004, 08:28 PM
I run a small electric heater in my shop. I have it set to 60 degrees in the winter, a little higher when I am working out there. In the summer I run my air conditioner,setting it on 74 degrees. I do not have any rust problems that way. NE Ohio does get humid in the summer. I figure the cost of running these are cheaper than buying new tools. http://bbs.homeshopmachinist.net//biggrin.gif

Paul in NE Ohio

Tim Mehner
12-07-2004, 08:35 PM
I have to keep the heat on all winter too. Set it at 58* and only turn it up when I'm out there. I get that dew on the floor when it rains alot, doesn't seem to matter where the heat is set at. I also get alot of condesation build up in the Fall before I turn the heat on full time. Damn winter anyways!!

12-07-2004, 08:37 PM
YOu guys don't know me veee-wie well..

I am the guy who refused to complete the house addition because of the higher heating bills this winter. (3x floorspace = more outa pocket)



12-07-2004, 09:02 PM
Dave I am a closet woodworker,I have cast iron in an unheated shop.
It drove me nuts,because a fine piece of maple will be ruined by a brown rust streak,oak is even worse,little rust and a drop of sweat and you have a black spot thats permanant.

So I have tried everything,oil,grease,silicon spray,paste wax you name it.
But the best without a doubt is Nu-finsih car wax,you know("after 50 carwashes the water still beads")

Well it works good,remove the rust,degrease and apply with a buffer or cloth.It won't solve the condesate problem,but it will reduce it and the rust will all but stop.I reapply mine every six months or so.

12-07-2004, 09:12 PM
Hey Gypsie,

Remember, it is a fine line between "fugal" and downright "cheap"!!! http://bbs.homeshopmachinist.net//biggrin.gif http://bbs.homeshopmachinist.net//biggrin.gif
Besides you cannot take it with you, and the govenment won't let you keep it while you are here so protect them tools!! http://bbs.homeshopmachinist.net//smile.gif

Paul in NE Ohio

12-07-2004, 10:07 PM
I've never seen a nitrogen purgeing unit. The ones I work on draw 100% outside air through pre cooling coils. Then a silicon honeycomb wheel that absorbs moisture. A furnace dries the wheel as it rotates. Then through post cooling coils. The air then goes through another heater. They can take 100% saturated air down to 10% RH. All this is for loading solid rocket propellant into air bag inflators.

Nitrogen sounds simpler.


12-07-2004, 10:19 PM
Sometimes when we get weather like this & I'm working away for a week or so, heating with coal, I just run a box fan on medium to circulate the air while I'm gone, this has worked for me.

12-07-2004, 10:20 PM
Nitrogen "blanket" on the top of flammable vessels. Is normal. The fumes is what explodes anyways. Has to have the proper ratios to give a good explosion anyways.

I put a rotameter, a tapered deal the lil ball floats in acording to calculated flow (my mig has one), a regulator designed for air or nitrogen use and Plumb it in. Kinda scary sometimes. Knowing if your "blanket" dissipates you can be blown to heck and back from the static off your clothes.

At Olin, aluminum class 3 housings would bond-weld within a month if not treated properly. I would use a good epoxy paint, Paper tape the legend plates over vaseline, Paint it all, Put liberal amounts of coppershield on the threads and let it go. I had to bandsaw off the lids on several multi-thousand dollar instruments set up by other techs there.

Ain't nothing like going around the lid with two hammers knocking and asorbing the impact with other hammer on something that is worth more than a years salary.

A old tech working with me, looked down at his coppershield dirty hands, said he thought he could take a drop of the stuff and paint a battleship.

David http://bbs.homeshopmachinist.net//biggrin.gif
Not got a clue what to do yet about the dew.

12-07-2004, 11:46 PM
I have the condensation problem in my location year-round too. After posting similar questions and hearing a lot of replies, the two I like are:

Higher cost version - temperature-controlled shop (my druther anyway just for comfort) which adds inspiration to spend more time in the shop to justify the extra expense.

Lower cost version - the lightbulb and cover idea. A lightbulb in the base might work without the cover too. I haven't tried this yet, but my gut tells me that even a 20W bulb would help a bunch, if not eliminate the problem.

In case you haven't figured it out over the past few months yet, I might be just a cheap as you, Dave. Maybe not since I've already come to grips with the temperature-controlled shop concept. I'm even willing to spend the extra up-front money for lots of insulation so I can reap the benefit instead of the utility co. which should help a lot. Of course that stuff isn't a reality so far, but it'll be there if I just stay focused.

Ooh look, something shiney.

12-07-2004, 11:58 PM
Oil surfaces, cover machines with a noncloth cover e.g. shower curtain, leave the lights on, shine a spot on critical machine areas and run a small electric heater to blow gentle warm air on the floor. And for heavens sake don't let morning moist air blast in on the machines when opening up for the day. Based on lessons learned.

As for the dog, give him a blanket and a bed of wood chips, works for some of our dogs and if he throws the stuff out then he does not need it.

Neil Peters