A few years ago I moved to a new house. Since that time I have noticed that the rusting rate of my tools has greatly increased, probably due to the fact that our area stays pretty damp and humid year round. I've tried a few different products to protect my tools, but a mixture that I've come up with seems to have similar rust inhibiting potential and be fairly economic.
I'm hoping that by sharing the recipe with the Instructables community, other people having similar rust problems might try it and tell me of their experiences. Please note that I've made this mix and it seems to work for me, but I haven't studied it extensively enough to make any claims about its effectiveness. So use at your own risk.
Step 1: Mix the Ingredients
The mix is simple enough. I only make up small amounts in a tin can as I need it. The measurements below are approximate (usually I just eye-ball it while pouring it into the can). You may find that adjusting quantities gives you a better mix.
2 parts Penetrol
2 parts amber shellac (the stuff in a liquid form that comes in a can, not the ground up flakes)
1 part (or less) 10w30 motor oil
LEGALESE AND CAUTION: I am not a chemist. I have made this mixture and used it without any ill effects thus far, however I can not state that mixing these or any other chemicals is safe. Please take proper precautions to protect yourself from possible chemical poisoning or injury.
Step 2: Application
The mixture will last in a liquid state for a few weeks. After that time, bits of congealed gunk will begin to show up. I've still used it with the gunk. Doesn't seem to affect anything.
If there is already rust on the surface I want to protect, I clean it off using a wire brush/sandpaper and motor oil or WD40. Then I'll wipe it down with a dry cloth.
I use a chip brush to spread the rust inhibiting mixture on the surface. If I go too heavy, I'll use a rag to gently blot off excess and even out the coverage.
The applied coating will become waxy after a day or so. I'm not positive how long the coating will last, but it seems to be pretty stable and I would guess that it will probably stick around until it is scratched or scraped when the tool is used.