The Stovebolt Site Forums The Shop Area Paint and Body Shop molasses

I bought a huge rubber garbage can w/lid yesterday and planning on setting up a "molasses" barrel to put some 265 and valve covers parts in to remove rust. I located a 50 pound bag of molasses on Tractor Supply webcite for $22 bucks or so, is that the correct kind of molasses? I've read up on it some, would like to try this, what I've read says it has to be "sulfated" to work, the webcite doesn't say "sulfated or not. This ia a dry sack, thanks, Lefty.

No feed/farm/garden store in your town?
I got a 5 gal bucket for 14 bucks so I'd say your in the ballpark.
9 parts water 1 part mollasses.

I have used liquid molasses. Just make sure that it is sulfated as that is where the acid/base chemical reaction comes into play. College chemistry was many moons ago, but if I remember correctly the reaction converts iron oxide into iron phosphate. Be patient as the process is slow. The ratio of molasses to water is roughly proportional to time of action meaning that a 5:1 concoction will work about twice the rate as a 10:1 mixture. Make sure to remove ALL of the grease as the acid will not penetrate the grease. Enjoy the experiment as it makes science kind of fun!

Maybe that was my problem was.... I used store bought stuff and tried some small pieces, didn't see where it did much. have to buy some at a feedstore or TSC....

John

the molasses method is a messy time consuming technique, electrolysis is way better

Bill

While I agree with you about reverse electrolysis being better Bill... if you have a convoluted or hollow piece that is hard to get to on the inside (and time isn't important) I like how the molasses works on the hidden areas.

As far as mess... I see no difference other than the moldy mess on top. They are both messy and the worked part still needs about the same amount of attention to finish.

yes, we do have a farmers cooperative store that sells feed also. Our Tractor Supply stores down here sell lots of feeds also. Usually Tractor Supply is alot cheaper than the Co-op, it's pretty high on most anything. It's usually a "last resort" kinda thing. I don't want to try any electrolysis thing due to wandering creatures in my yard that might tend to screw with things. I figure a molasses drum with a lid on it should be pretty safe. I'm in no hurry and have LOTS of things to try in it, as I have about 8-10 old rusty derelicts at any given moment and move back and forth between them all.

in particular I dont want to cause danger to my neighbors cats or kids, and I have coons and possums and squirrels and all kinds of things like that which wander my yard at night. I had a family of coons living in a large oak tree hollow and they just couldn't figure out why I wasn't friendlier. They wanted to visit with me and would surprise me by sneaking up on me and getting under my lawn chair. They had zero fear of me. I'd had for their little paws to be grabbing electrodes and pulling on wires and so forth, because they are curious by nature.

electrolysis can get the hard to reach spaces too, with time, and is easier to clean from those places, the sugar is harder to rinse clean and corrosive, washing soda isn't - for my money, molasses leaves a toxic waste - c.f. the recent spill in Hawaii, make sure you dispose of the sludge properly

Bill

I was wondering with the electrolysis metheod, does it create hydrogen gas?? Would it be alright to use indoors? Where can more information be found?

John

Yes it makes hydrogen, no don't do it indoors, less its an outhouse you don't care about. Use a plastic container, use a trickle battery charger, hook neg to the part and use something like rebar or some other steel item to pos.

there's a tech tip on it, there's also numerous pages about it on the web, just google 'electrolytic rust removal', also a number of Utube videos showing the process

Bill

If you are a safe person and have a good place to lock up, Lye as is recommended by Brownell in his book will work really well. Let parts soak for two days and they are squeeky clean. Grease dissolved, not rust, that's for my sandblaster. Wash off with soap and water, prime. The lye I buy at ACE is safe to put in sewer. If you heat it, it will even work better according to his book on restoration. I put all parts together. nuts bolts washers and any other greasy part. He says 24 OZ per gal. He covers ALL of the methods mentioned here and more. "How To Restore Your Chevrolet Pickup" Tom Brownell. He was a contributor, advisor and friend to the Stovebolt. Very good book especially for AD.

I found the Tech Tip on it Bill, thanks.

I have a copy of that book, was one of the first ones I bought.

John

You need a certain amount of amperage per square inch to even being to have an effective reaction. 2 amps (off a trickle charger) is not going to do a very large part unless you let it sit a long time.

I've done just about every rust removal process on the net (media blast, molasses, electrolytic, phosphoric, grinder, pressure washer) and the overall best way is good old fashioned black beauty 40/80 grit and a pressure pot or siphon blaster.

Nothing else is as quick and easy. As long as you don't use sand, a good P-90 particle filter will suffice.

I'd like to meet the meathead that warps a panel with a properly set up sandblasting kit. I use 40psi and unless the rust is very, very deep it all comes off with no issues. Plus you can switch to walnut shells with the same rig and get the paint off if that's all you need.

Every other process requires a CLEAN unpainted part.. that's extra steps that if not done right, will cause you to repeat the process till you do get it right.

Found it:

http://electrochem.cwru.edu/encycl/art-a04-archaeology.htm

5ma per cm2 up to 50ma per cm2. Constant current power supplied at .005A per cm2 will not form hydrogen formation.

Something like an S2 oil filter would be 408 sq inches (5x8 in cylinder - rough dimensions). 408in2 = 2632cm2 * .005ma/cm2 = 13amps (low amp) or 2632cm2 * .05ma/cm2 = 131A (!) for moderate amp electrolysis.

That's really out of the range of most 'battery chargers'.

Lower amperage will work, but will take longer and since the effect is 'line of sight' you have to really play with the part to get it completely rust free.

For small parts, its not a bad way to do it, molasses is easier (slower) but media blasting is quickest.

I misread the post and said Lye for grease. He said rust, sorry. Blasting is by far the best way for rust. No sulphated nuclear hydrogen phosphoric acid nitrogen poisoning, just silicosis.