Cast Iron winter storage in MN

[Joel Cohen]

I’m about the shutdown my shop for the year. The last few years I’ve schlepped my 6” jointer into the house for storage. I now have too much cast iron, a tables saw, bandsaw, drillpress, etc, so it’s gonna stay in the garage for the winter.

During spring/summer/fall, I run a dehumidifier, coat all cast iron with Boeshield T9, and Johnson’s paste wax on top. Have had good results with this combo.

My current plan is to clean all the cast iron with mineral spirits, let it dry, apply an extremely heavy coat of T9, and then press painter’s plastic onto the coated surfaces. I just read a review of a bunch of different rust preventers done years ago by FWW. They advise the CRC 3-36, so I’m considering swapping out my t9 for the 3-36.

I can’t run a dehumidifier in winter because it get so cold here. My garage is not insulated and detached, so heating is not an option.

Is my idea of putting plastic over the coated surface a bad one?

Any advice appreciated.

[Greg Quenneville]

Does modern day Minnesota still stay frozen all winter? If you have a few freeze/thaw cycles I would maybe do something a bit heavier. The local Felder dealer suggested shipping machines (for example) with a generous coating of heavy motor oil followed by a layer of heavy paper over top. This keeps at least some oil in place on the machined surfaces.

Makes for an hour's work in the spring with turps and rags, etc, followed by the wax treatment.

I (now) live in the Australian version of Florida, and here too rust never sleeps.

[Mike Cutler]

Don’t put plastic over the surfaces. It will trap moisture and create its own environment.
We get a lot of condensation cycles in Connecticut during the winter. Condensation is what causes the problems for me.
I tried all of the methods you described and they either failed, or were such a pain in the butt to remove it wasn’t worth the effort. My shop is only protected from rain, as it is in the garage. There is no climate control in my shop.
My solution for the past 25 years or so, is to wax them liberally, and cover them with a layer of heavy cardboard, and 3/4” plywood on top of the cardboard. We’re only referring to the large flat surfaces. I have two tables saws, two bandsaws, a shaper, jointer, and planer, that are all done this way.
It works. I haven’t been doing much woodworking the past few years, and used my Jet 15” planer for the 1st time in probably three years last week. I took the plywood and cardboard off the bed, wiped it down, and ran wood through it. Same with my shaper.
For some reason the jointer is the hardest to protect??? I can protect the bed, but the fence mechanism can get a little rust bloom in it.
You have to stop the condensation from forming on the surfaces when the dew point changes. That’s the killer.
You may not stop it all, but you can mitigate the cleanup in the spring tremendously,

[Steve Rozmiarek]

Does anyone just use cosmoline? It works really well on military stuff stored for decades in bad conditions, a winter ought to be a breeze for it? You already have to use a solvent to clean in the spring, in my experience the cosmoline comes off pretty easily with that approach.

[brent stanley]

I have two shops (for now!) and one is a steel, Quonset hut which warms and cools so fast that condensation is a huge problem. My solution has been so effective for me, I still can't believe it. I purchased a bunch of heavy plastic bags (the ones made to go over pallets) and I coat the tops afresh as normal (T9) and cocoon it with the heavy plastic bag making sure to seal it up fairly well so air can't circulate in and around it. I used to throw a box of dessicant in with it as insurance, but don't bother anymore. I no longer have problems with condensation and rust, and the machine is ready to go when I pull the cover off. Now if it's freezing cold but the air is warm and humid when you whip the bag off water will condense on it before your eyes, but that can be managed.

[Richard Coers]

Temperature is only your problem with it's relation to dew point. Have cast iron at 25 degrees and expose it to 35 degrees with higher humidity and you get a layer of condensation on the surface. Not have any exposed surfaces (plastic cover) and the condensation builds on top of the plastic. I'm not going to recommend the plastic, but I have seen a table saw that had a piece of cardboard on the table. No rust under the cardboard, lots of rust on the exposed cast iron. You might consider bedding some VCI paper in the T-9. https://www.theruststore.com/Rust-Prevention-C4.aspx

[Mike Cutler]

Steve

I’ve used the cosmoline that is currently available, and I’ve used CRC, LPS-6. Both definitely protect the surface, but I just didn’t like the cleanup. The LPS was quite the chore to remove.
If I was going to layup a machine for an extended period of time. Cosmoline would be a good choice.

[brent stanley]

Temperature is only your problem with it's relation to dew point. Have cast iron at 25 degrees and expose it to 35 degrees with higher humidity and you get a layer of condensation on the surface. Not have any exposed surfaces (plastic cover) and the condensation builds on top of the plastic. I'm not going to recommend the plastic, but I have seen a table saw that had a piece of cardboard on the table. No rust under the cardboard, lots of rust on the exposed cast iron. You might consider bedding some VCI paper in the T-9. https://www.theruststore.com/Rust-Prevention-C4.aspx

This is actually the issue, so if that humid air cannot reach the surface of the cold cast iron....then it cannot drop it's moisture on the colder surface. Trapping humid air in there CAN be a problem, but wrapping it up in the cold, dry fall air will help. Also, a box of dessicant will help if you want some insurance. The bag still allows the unit to warm up fairly efficiently when the outside air warms up, but it limits the ability of humid air to access the condensing surfaces.

[Joel Cohen]

Mike,

Which cosmoline product do you recommend?

They have sprays, greases, brush on liquid, etc

https://www.cosmolinedirect.com/cosm...t-preventives/

joel