I have read some posts about removing rust with molassas soak. How long does it take? I have some hyatt bearings that have light rust, no pits. How about gears? Just light rust but hard to reach with wire brush. If this can be used on bearings and gears, is coating with light oil good to keep rust from returning?
I think the problem is that it works but slow as
Well you know. I would try that evaporust. From tractor supply
I use a rust remover called Metal Rescue from Home Depot or AutoZone. Spray down the bearing with brake cleaner so there's no oil on it before soaking. Put the Metal Rescue in a glass pan and microwave it for a minute so it's a little warm. Only takes ten minutes to clean off light rust. After soaking, scrub the bearing in hot soapy water, blow dry and coat with oil. Keep re-using the Metal Rescue until it stops working.
I've played around with molasses for removing rust and it does work very well but I do not recommend it for anything with a machined bearing surface such as hyatt bearings or gears, etc.
Metal Rescue is basically the same as Evaporust but is much less expensive. I think either would be a better choice for what you are doing.
I have used the Molassas bath for rust removal and it does work but is SLOW. The advantage is, I think that it does not have any harsh acids in it so only acts on the oxide (rust) and not the base metal so therefore might be better for machined parts and stressed surfaces ??? I used it at about 1 part Molasses to 3 or 4 parts hot water, mixed to dissolve the molassas and then the part/s left to soak in a lidded plastic tub. Light rust might take a day or heavy rust a week or more ? But is only for iron / steel parts - no brass, plated or alloy.
Only disadvantage is rust turns to a black gungy slick and parts really need waterblasting to clean them and then dried off quick in an oven. You may get surface rust before the parts dry but just wipe with an acid neutraliser to clean that coloring off.
2nd disadvantage is that black 'gunge' will stain hands and any clothing it contacts.
The remaining bath can be used over until it gets too week / polluted with sludge of dead rust.
Also much cheaper than Phosphoric acid based rust killers.
If you use molasses do not use the UnSulfered stuff, get the stuff from the feed store. It is a slow process but is much cheaper than the rust removing products on the market. Since it is summer place the soaking tub in direct sunlight this will speed up the process slightly. Bottom line if you have the time molasses is a good option If you are in a hurry then spend the money for the commercial product.
If it's only "light" rust, how about trying good ol' CLR? then coat surfaces in oil for prevention.
Sorry, This popped into my head.
Thanks for reminding me. Carry on.
Having used quite a bit of molasses for rust removal on my Maxwell I have to agree with Eric that as well as it works on most rusty antique car parts it does put an unwelcome ETCH on any polished surfaces.
Molasses will not remove paint, so parts need to be free of coatings. Being water based, the mixture will not work on greasy/oily parts. Cast iron parts left too long can be ruined. The mixture seems to eat the carbon in the iron.
There are two real advantages. The stuff is cheap. It is non toxic and can simply be disposed of by pouring it out on the ground. My wife even likes the smell!
Allan from down under.
Howard Dennis articulated it better than I did.
I had some NOS camshafts that my dad picked up 65 years ago with various degrees of surface rust.
I soaked them in molasses and they came out clean but etched.
I had used molasses on small items in the past with great results but not on machined parts with bearing surfaces.
I use feed grade molasses diluted with water. If you read the gallon jug, it says it contains propionic acid as a preservative. Don't know what that does to the metal. I think but I am not sure that molasses in and of itself may contain citric acid.
I like using Evaporust for certain items because it does not seem to affect paint or chrome or nickel plating. I used it to remove the rust on drill press tables that were painted on the sides with great success. I've also used it on a few chrome and nickel plated items. I know that it does strip galvanized plating.
I recently had a conversation with a retired chemical engineer who plays around with vintage aircraft. His recipe was 9 parts water to one part Feed Molasses and let soak for 1 to 3 weeks. In his opinion this was a very safe way of stripping off rust compared to any acid dips because the latter will cause embrittlement in metals which is dangerous for certain drivetrain parts such as spindles and tie rods.
I have not yet tried the Molasses method but will be doing so in the next month. I have heard of some guys using a 12 volt charger with electrodes to speed things up. Comments anyone ?
( I have tried Evaporust and it does work nicely but Molasses is a lot cheaper )
Thanks for the input from all. You guys never let me down.
Ed, I ran a test using some rusty re-inforcing rod. The best mixture I found was two parts molasses to three parts water. Less molasses was less effective, more was no more effective. Your feedstock may vary.
Allan from down under.
In the summer it will also draw all sorts of critters, gnats ,fly's, crickets, bees and wasp. plus coons and possums. Been there done that.
I have done it in the basement.
I have not soaked excessively large parts.
I use sealed containers or put the container in a trash bag and seal the bag. For example, when I soaked the camshafts mentioned above, I used a plastic wallpaper tray inside of a plastic trash bag.
No problems with critters, etc.
Bump to get rid of the spam
I have used, and am using molasses right now. I use it 1 gal of molasses to 7 gals of water. It works great for me. I have a dash soaking right now. I've done a couple dashes, door latches, window cranks, trailer wheels, a ton of small parts. I made a couple of vats out of 1x10's, with a plywood bottom. When plastic tubs are to small to use. I made side braces for one, because it's 48" long.