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I hadn't been to my shop in a couple of weeks. We had record cold temps here in Houston, but after about a week of freezing, we hit 75 with high humidity. Guess what happened? A light coating of rust on every bare metal surface.
What is the best treatment to prevent this? I've been waxing but obviously that won't stop this type of attack.
I remember someone using Varsol or Ospho? I was thinking about treating it and maybe a spray coat of lacquer?
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This is not an unusual problem where night time temps get chilly and then it warms up to a humid day. Your tools get cold and then the warm humid air condenses on them. Long term, the partial answer is good insulation so that inside temp changes are not as extreme. Wax coatings and drawer storage will continue to further help. Short term heat on chilly nights will, of course, be the ultimate solution.
I found out by accident that if you keep a small fan running on chilly nights (actually early mornings) that it will keep exposed tools from collecting condensate. I don't know the physics of it, but it does work. Just a small table top fan is all it takes. Even better if it oscillates.
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I use Boesheild. But be careful the can loses propellant quickly. I think my next can I will just puncture then but the stuff in a manual spritzer. It works great. Super slippery. Almost like the Clark Griswold “non-chloric, silicon-based kitchen lubricant. You just spray on, wipe off and leave a thin coating. Reapply ever 4-6 months.
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It's a common problem for me, that's our weather on a lot of days. I picked this up over at LJ. I bought some magnetic sign material (a roll of it) and cut it to fit the tops of my tools. I should mention, my tools are simply stored at the moment waiting for my shop to be insulated so I can keep it heated. Anyway, it's a little cumbersome if you're using your tools daily...but if they sit for more than a few days, it's great protection. Otherwise, the cast iron gets a coating a Johnson's paste wax to keep it protected. The wax has another advantage, it makes the surfaces really smooth. The wood just glides across them. at least for a while.
I started with absolutely nothing. Now, thanks to years of hard work, careful planning, and perseverance, I find I still have most of it left.
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I would be really careful with the magnetic sign material, if any water gets under that it will still rust. I had magnetic signs on a truck and I thought it would be safe. Turns out that is where the rust formed and not any other place on the truck.
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put a 15 watt incandescent lighted bulb inside the table saw. It will raise the temperature of the saw a few degrees above the ambient air and prevent condensation.
There are also dedicated small space heaters that do the same. A shatter resistant bulb is an advantage. The amount of electricity a 15 watt bulb draws is negligible.
Incandescent bulbs are harder to find lately but the shatter resistant ones for ovens are still available.
You only need to have the cast iron 1 degree warmer than the ambient air to prevent condensation.
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01-24-2018, 03:35 PM
(This post was last modified: 01-24-2018, 03:41 PM by Willyou.)
On issues like this we tend to zero in on the obvious CI surfaces like the table saw. However, the OP mentioned "every bare metal surface". It is difficult to keep individual tools like pliers, screw drivers, chisels, and other exposed metal objects protected. While individual tool protection is good, it is more efficient to fix the problem shop wide keeping in mind that the phenomenon is generally seasonal. Full shop insulation is probably the single best all around solution that solves other problems as well. Before my shop was insulated, I would find my exposed tools dripping wet on cold mornings in the spring. After insulation, only occasional problems. And, the shop is only heated on an as needed basis.
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(01-23-2018, 07:31 PM)Danny in Houston Wrote: I hadn't been to my shop in a couple of weeks. We had record cold temps here in Houston, but after about a week of freezing, we hit 75 with high humidity. Guess what happened? A light coating of rust on every bare metal surface.
What is the best treatment to prevent this? I've been waxing but obviously that won't stop this type of attack.
I remember someone using Varsol or Ospho? I was thinking about treating it and maybe a spray coat of lacquer?
I cleaned and waxed my tools last October, so my wax coating is not fresh but not too worn yet. During our recent weather we moved a bunch of the wife's potted forest into the shop, but left a few ceiling incandescent lights on. I haven't seen a spot of rust develop on anything, even with the soggy recent day's we've had.
I did apply a coat of polyurethane last weekend. What dried in 8 hours a few weeks ago was still tacky after two days.
Shame on the men who can court exemption from present trouble and expense at the price of their own posterity's liberty! - Samuel Adams
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Foam insulation board sitting on cast iron tops
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I fought this same issue several years ago. ( i live 165 miles east of you so same weather). On all of my cast irom tops I have sprayed Bostik Glidecoat. All of my machines are either covered with a plywood cover (tablesaw and bandsaw) or covered with Tool Saver Machine covers from HTC. If I am bot going to be working for a while I will make sure that all machine surfaces are coated with SlipIt ( a soft wax). This does not seem to interfere with stains or glue. I now spend just a few minutes each day to save me from buffing rust off.
Hope this helps
