Hi Mark, I just found this thread again. Sorry but the 2nd pic in my post of the extractor mounted to the motor - that's some red silicone left on there. I know I'll need to wire brush it off, and treat the bare bit. But it ain't rust in a porous weld. Now some blokes don't need to be a chemical engineer to know that an acid when combined with a base will effectively neutralise the parent material. All I did was hot rinse/soak in hot water + bi carb soda, (about 45 mins.)then rinsed off with LOTS of water. Heated the parts with a torch to remove what moisture was left, then soaked the part with Ranex rustbuster - a phosphoric treatment. What exactly do you think I might need to do - extra? Is there another process I need to do? Not being a smarty pants mate by all means, I just would like to know what else could I can do to keep the dreaded worm away. As for soda blasting, a few painters have warned me off this route - I went low pressure, with garnet media. What are your thoughts? Cheers Mudgy
I also have the jag rotors seen on page 2 of this thread from (now) nearly 3 years ago... still sitting here, bare. Not one speck of rust coming back. And they're iron disc rotors.
I've been using Evaporust, Blue Lightning(heavy,heavy rust eliminater) with great results. but for large parts would be expensive, do I did the citric solution yesyerday about 3:00am the pis mt result...I'm way impressed!!!!
I used a citric acid bath on many of my rusty '59 Ford parts. I used a mix of 2 lbs of CA to about 12 gallons of water in a 30-gallon Rubbermaid tub. You really need to get as much of the grease and grime off first. I've dipped backing plates, suspension parts, etc. They come out with zero rust after a 3 day dip. Light rust, goes away over night. I have a separate spackle bucket of baking soda and water to neutralize the acid.
I found this method in Vol 75 #6 issue of the Horseless Carriage Gazette. Bill Ottemann, the author suggests using beet pulp. It is a horse feed that a bacteria grows in which eat iron oxide. A 50lb bag is about $20. You do need to prep your mixture of water and beet pulp about 2 weeks before you use it to get the bacteria to grow. Then all you have to do is soak your parts for a few days to a week and they will come out looking freshly sandblasted. Just wash them off, metal prep and paint. The process is slow but when you are done you can poor it on a tree outside and it will act as a fertilizer/mulch. Posted using the Full Custom H.A.M.B. App!
Just finished reading this entire thread. Very informative. Used the search function, read some more. Question - Can anyone say definitively if a citric acid soak will create any problems with a frame? I read that it should not be used on CAST parts, but frames are not cast. It would seem to me that it would not create any problems, as I've seen plenty of frames that had mild to moderate pitting scraped down, treated with Ospho or the like and painted. Properly neutralized with baking soda should stop the acid from eating the metal any more. Yes? No? Thoughts? Thanks... Chris
I didn't read every post here, but there's some very interesting advice. I'd like to add: -Cold is slower. That's why a cold battery gets weak. Slow electrolysis at low temps. Almost every chemical process goes faster when things heat up. -Keep a big bucket of clean water around while working with strong acids and bases, in case you need to flush your skin or eyes. Seconds count here. It's much faster than finding the hose. -Be careful neutralizing when you etch with strong acids. Don't dip a strong acid coated part into a strong alkali solution. Rinse with water first or use a weak dip for a longer period. -Acid eats metal. Period. What did the factory do when they wanted to lighten a unibody car for drag racing? Acid dip the entire thing to thin the metal. -Acid eats your concrete floor. Stains it too. Stone & glass as well. -Acid solutions get weaker with use, as you are literally neutralizing the acid with the rust. -Adding water to a battery is safe only because the battery acid is dilute. It's already almost all water. I worked at an anodizing plant where they kept strong acid, and some guy's fun was to drop little water bombs into strong acid, out in the desolation of the back lot. He got brave and rattled the whole building one time, shooting debris through the air. I have a healthy respect for this stuff. I have been using electrolysis to de-rust parts, and vinegar too, but vinegar more for just for stripping plating from little plated things I want to weld or paint. I've used lots of phosphoric acid prep solutions in the past years, generally Jasco brand or NAPA; and usually our local water is alkali enough to neutralize it given enough time and water. Otherwise a weak solution of washing soda & water will kill the acid fast. So far my biggest "tank" is only 15 gals, so I'm not dipping fenders yet. Lots of nuts & bolts. This was before & after 2 days in the electrolysis bath & a good washing to remove the soot that is left behind. That pulley sat in the water rusting for years too. You can tell from the pits how deep the rust was.
ok. here is what i was planning to do. four 55 gallon poly barrels. each one filled to about 30 gallons for any overflow. 1 with purple power to degrease, 1 with a tide and water solution to rinse off, 1 with wood bleach (oxlac) acid solution to de-rust and 1 with sodium bicarb and water to neutralize. also inside each barrel pvc tubing with holes in it at the bottom and an air inlet to agitate the mixture. since reading this thread maybe change to ca for the de-rusting barrel. now what is everyones thoughts on this? please don't let me blow myself up if this won't work!!
No it won't hurt the frame unless you just go crazy with the acid. The key to using acid is to monitor the process closely. What took 12 hours yesterday might happen in 6 tomorrow, if the weather warms up.
With all these systems there is lots of chemical residue to wash away. How do you dispose of the rinse water? Not down the storm drains which drain to waterways, I hope!
Don't put the acid barrel too close to the caustic barrel. As for residue, I'm not making much and most of it is just rust & mud. I scrape it out on a patch of hard soil to dry, & shovel it into the trash bin. This is not like doing chrome, where you make serious toxins. As for waterways, we don't have them. Our storm drains empty into re-charge ponds which let it filter through the earth.
Acid works great...just don't use it on structural/suspension/steering components. Exposure to acid can cause hydrogen embrittlement.
It's been six? months since I last posted and I've cleaned two bodies plus a bunch of other parts. I'm still using the same batch of citrus and I haven't noticed any slowing of it's action. I'm using a weed sprayer with baking soda to neutralize and another sprayer with Prep-n-Etch to hold off the rust. Here are some of the results. Norm
I thought this was interesting regarding the hydrogen embrittlement problem and citric acid. http://www1.asminternational.org/AM...icID=1999&ForumActiveFlag=Y&TopicActiveFlag=Y
ulu, isn't the acid and caustic barrel the same one? http://dictionary.reference.com/browse/caustic?s=t http://dictionary.reference.com/browse/acid?s=t
Nope, Caustics (alkalies) and acids are like fire and ice. They destroy each other when mixed equally strong. Did you ever mix vinegar (acid) and baking soda (caustic)? The reaction is immediate and unmistakable.
Three weeks after I pulled that floor panel out of the citrus I put some model A fenders into the tank. Five days later (the standard time), they were only half clean. three days later no better. I checked the mix with my PH meter and it reads 4.8. Four weeks earlier it was 2.8. I thought this stuff was going to go on forever. It was a good run anyway. Cleaned close to two four door bodies plus other assorted parts for $105. Time for another batch. Found my next tank on an online auction it's a containment tank for controlling oil tank spills. It's 77" x 36" x 36' deep. 275 gallon capacity, but a bit spendy if bought new. Norm
Thanks to all who posted in this thread. I have recently tried this and found it to be an excellent method. I experimented with some smaller parts and now I'll be looking for a storage tank to do a full cab. Do you really care what I used to post this message?
Came back to add pictures of my most recently cleaned parts. This mix is still working great and still at 2.8 acidity. A couple of comments: Someone posted to another thread that they would not "Dip" a frame. Not because it would weaken the metal, but because it would clean the rust from between the layers of frame sections and from around rivets. I don't know this, but I would sand blast a frame anyway. Also, I'd like to say again, citrus is not a "strong" acid. It's no stronger than vinegar. When I pull parts out of the tank bare handed I wash them off with water as soon as possible. I do try to use rubber glove as much as I can. Norm
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