Question about rust

[Mike in Mystic]

Hi again,

Well, I just posted about my pleasant table saw tuning experience, so I have to offset that with a bit of a frustration.

Before I tuned the saw, I cleaned the surface of some light rust. I live in CT and this winter has been VERY cold. My shop is in a dedicated bay of a two-car garage, but there's a stud wall separating the two bays (a door gives access between them). The "shop" is about 6 feet wider and deeper than a "typical" garage bay, which puts it at about 16'x24'. The walls are all insulated, but there are two fairly large windows, two sky lights, and the garage door isn't insulated.

I heat the shop with an 80,000 BTU propane heater, which generally does a pretty good job. A few weeks ago when the outside temperature was about

35-40 deg. F, I was able to get the shop from about 40 degrees to about 75 degrees in maybe 20-30 minutes. Today, the shop was at a nice and cool 21.5 degrees F and it took a LOT longer (about 1.5 hours) to get to 70 degrees.

Now to the rust question, the light rust that I found on my table saw wasn't too big a deal. I just sprayed the surface liberally with WD-40 and let it sit for maybe 10 minutes, then used a green scotch brite pad and my ROS to buff it off. Then I sprayed it with some Topcote and a good layer of paste wax.

Last week I had to do the same thing to my jointer (the 6" Delta professional). The only thing different was the amount and severity of the rust. The jointer had some pretty thick rust and it was on just about every cast iron surface on the tool. It took me a LOT of effort to remove it, even though the table saw and jointer had sat idle about the same amount of time.

Tonight, when I started to work on the tablesaw and as the garage/shop heated up (using a 80,000 BTU propane heater), I noticed that the jointer surfaces already had signs of light rust again (pretty faint, but still there, and after only about a week since I cleaned it, and coated it with Topcote (no wax on the jointer)). As the room became warmer, I saw SEVERE condensation on the jointer. It was literally puddling up on the tables. I was mystified. I checked the tablesaw surfaces - no condensation. I checked the bandsaw table - nothing. I even looked at a few of my handplanes, etc. and no sign of condensation - it was just happening on the jointer.

Does this make any sense?? It sure explains why the jointer is suffering the most from rust, but I don't really get why the jointer surfaces would be so much colder than the rest of the tools, which is the only reason condensation would preferentially occur there. Has anyone else experienced this kind of thing?

I read the interesting review of rust removal and preventative agents in the latest Wood magazine and I have some Boeshield on order. I hope it does the trick, because I don't want to have to deal with this every week or two when I need to use the jointer.

Sorry for the long-winded post, but hopefully someone has some insight into this.

Mike

[Mike in Mystic]

nope, the table saw sits right in front of it (about 4 feet away). The jointer is next to the table saw, and is probably the same distance from the regular access door, but I would think that door provides more insulation. Honestly, the garage is cold as hell and I doubt there's much variation within the space. Even when I turn on the heater, you can detect clear zones for some time until the heat has time to thoroughly do its job. The bandsaw is actually right up against an outside wall, and I haven't seen a lick of rust on that table the whole time I've owned it (and I only but a coat of Topcote on it when I first tuned it up).

Mike

Mike

[MSgeek]

experienced

[todd]

experienced

The only reason that I can think of why your jointer would be worse than the other tools would be because the cast iron in the jointer is thicker than the other tools and doesn't heat up at the same rate.

todd

[William]

That's what I was thinking. The underside of the jointer table may not get as much airflow either. The warmth from the heater may be driving moisture into the air from all over the shop, and the jointer stays cold enough to start collecting it. A dehumidifier might be a good idea - start it up as soon as the heater is turned on, and park it next to the jointer. -Wm

[Edwin Pawlowski]

I think it has more to do with the mass of the castings rather than just the temperature. The jointer is probably taking longer to heat up. two weeks ago I turned on the hat and went back to the house to let it warm up. When I returned, the tablesawy had a coating of ice on top from the condensation. At that point, I cleaned it up, turned off the heat, and read a book instead of woodworking. Going from a minus zero to working comfort just is not happening. I'm not trying tomorrow either. -4 expected tonight.

[Gerald Ross]

When you burn hydrocarbons like propane, what do you get (ideally)? CO2

• H2O. Unless you are us>

[Edwin Pawlowski]

Good advice but not very practical for most of us. The cost of heating a detached garage for the 6 days and 18 hours that I don't use it in a week would buy me some nice wood to work on in milder weather. When the temperature gets to -12 like it did a couple of weeks ago, that light bulb is not going to help much. .

Electric heat means adding new service to the garage, maybe to the house for the extra load. Steam heat means keeping the temperature above freezing all the time and is expensive to install.

[Silvan]

You already know about thick castings and increased humidity and stuff. Now think about a fan. I've had a cheap box fan running 24/7 in my shop, moving the air around, since last fall. High humidity, low humidity, high temperatures (up to 120 F inside the shop) and low (down somewhere below

10) I haven't had anything rust except for stuff that's been kept out of the moving airstream.

Granted, I don't have any big iron in my shop, but I'm still impressed with the efficacy of this inexpensive prophylactic. I used to have to wax

*everything* frequently. Every chisel, every screwdriver, every saw blade... Rust was a severe problem.

[Mike in Mystic]

I agree with , Ed, although thanks for the suggestions Gerald.

I just can't afford to install much more for heat than what I'm using - a simple job site (non-vented, as you surmised) propane heater. I understand about the source of the condensation, I just didn't expect there to be such a difference in how the different cast iron surfaces in the shop behaved in that environment.

I haven't seen ice yet, Ed, and my goal is to get about 5 or 6 hours of shop time in today, but maybe I'm being too optimistic. I never thought I'd say this, but I'd rather have 2 feet of snow than this cold f&&king temperature. I don't physically mind it, but interfering with shop time makes me grrrrrrrrrrrrrrrrrrrrrrrrrr.

Mike

[Anthony Diodati]

I would try that as well. Maybe run it full time. Tony D.

A dehumidifier might be a good idea - start it up as soon as the heater is turned on, and park it next to the jointer. -Wm

[Charlie Self]

Mike in Mystic notes:

You might want to try a small dehumidifier, running it for a few hours during heating and after...then shut it down and empty it until the next time.

Charlie Self "Character is much easier kept than recovered." Thomas Paine

[Rob V]

Mike,.

I was having the same problem - to the point where I would clean and wax them and a few days later it would warm up and rust would form.

It happened one day and I noticed I corner of hardbard was over the TS - I moved it and there was no rust under it - the rest of the TS top had rust all over it. So I tried a little experiment - I cleaned both my jointer and TS - I took a peice of HB cut it to the lenght of one of the jointer beds. About a week later - it got down to about 25 then warmed to about 60 the next day. Again - the TS and jointer were showing signs of rust (despite the wax i did the otherday) - I moved the HB and it was still sparking clean. Now I have

3 peices of HB - 1 to fit onthe TS and 2 for the jointer. All marked - DO NOT USE OR THROW AWAY.

Been using this for about 2 months now w/ great success. I just have to remember that when im done for the day - to put them back on!

Good luck

-Rob

experienced

[mel]

I'm glad somebody else had this problem.. I thought I was going nuts. Why only the jointer and not the other tools? BTW, I read the same article and in it they claim Empire's Topsaver was the best rust removal and second best preventative. I got some, used it to clean up the badly rusted used jointer I had purchased after sanding the excess rust away. It worked so well I sprayed what little I had left on the TS, small bottle...doesn't go far, and with little effort it removed the stains with ease. 8 days later with high humidity nary a sign of rust. I might mention I did apply wax afterwards. Good stuff...

[Phisherman]

1. Water is the most common catalyst of rust.
2. Rust requires oxygen.
3. Moisture moves away from warmer temperatures and toward cooler temperatures.

You can use these facts to protect your equipment. Keep your shop as dry as possible. Keep your iron surfaces protected with some kind of coating. Place a 4 watt lightbulb inside or under your cast iron tables, just enough heat to make the temperature higher than the surrounding area. Burning kerosene, propane, wood, or combustion of any kind in the shop produces moisture--Infrared lamps or electric heat is better at keeping your shop dry.

[Phisherman]

Even a 4 watt bulb will heat the iron to a slightly higher temperature than the garage itself. It doesn't matter if the temperature is 80 or minus 10. All you want is a slightly higher temperature on the rust-prone area to chase away the moisture.

I fI had a garage shop, I'd spend the money on lots of insulation and caulking. I know its tough to seal a garage door, but it can be done.

[Wilson]

A classmate of mine told me that soaking small rusted items (drill, mortising bits) in coca cola for about 2 weeks will break the rust free. I haven't tried it yet. I did acquire about $1,500 worth of tools for $200 last summer from a former workmate who was liquidating his father's old tools. Many of the small drill bits and metal parts of the larger tools had rust. We tried navel jelly with no success. Some parts are too small use steel wool. any suggestions?

[Swingman]

A fan might not be the sole solution in every climate, but it can be a big part of the solution in many. It's just too simple, and cheap, a solution for most folks to take seriously ... until they try it.

Other than the occasional coat of Topcote, a fan running 24/7 is the only rust prevention solution I need. I've been in this particular shop, in a high humidity, rapid change in temperature climate, for over two years. Fan, mounted high on one wall and blowing across shop, runs 24/7, NO rust on any tool surface whatsoever.

Just cleaned rust off the tools, for the third time, in a shop for a lady friend who no longer has a husband. She has the shop and tools rented out, but the lessee has yet to take possession. The shop is less than two miles from mine (and drier overall because mine gets water in around the edges when it rains heavily), and her cast iron surfaces rust constantly ... difference between her shop and mine: NO fan.

[dave martin]

The propane burner requires about 10 cuft air for each 1000 btu generated. Each 10 cuft of air burned generates about 1.6 cuft of water vapor. That's a LOT of water.

To prevent moisture buildup in the room you must get rid of the water generated by providing an easy exit for it; the exhaust gases from the burner should go out a stack & not directly into the room.

Also try spraying a thin coating of a non-wetting agent like a silicone onto the cold cast iron surfaces. That will slow down the condensation of the water.

[Edwin Pawlowski]

Sure, try the Coke on the small parts. It is acid and will break down the rust.

Wood magazine just had an article about rust removal and prevention. Worth a peek. -- Ed [e-mail]