For small parts in a smaller bucket, I picked up a Kitchen Aid strainer in the supermarket. I made a handle from safety wire and hook it over the edge of the vessel. Old cat litter pails with covers are pretty good for a small batch.
Can some one tell me the purpose of the agitation? Just to knock the rust loose? Or dose the acid fall out of suspension? I am doing a small test in a tote can I just give it a shake every few hours?
Citric acid will also strip zinc coatings off of new hardware. I use citric acid when I'm going to weld zinc coated hardware, I don't want to breath that stuff in. over night seem to remove most of the coatings. I like citric acid because it's faster than vinegar, but yet still safe enough to dump down the drain. I used to get it from the local baking supply store.
To me, the purpose is to cause some flow thru areas like water jackets so as the rust comes loose it doesn't just settle somewhere else in the jacket. It probably doesn't hurt with keeping the acid and water mixture consistent as well.
Citric acid is great stuff, i have used it with good results. I bought a kid's pool and made around 220 gallons mixture of that stuff. Its a lot, but i needed that much to get shoebox hood and NOS door cleaned from surface rust. It works fine on sheetmetal, but springsteel gets ruined with citric acid.
This how i do it: 1. I rinse all the loose dirt or use degreaser to get all the loose crap out of the piece. 2. I sunk the the piece in citric acid mixture and let it be there over 24 hrs, it doesnt hurt if its there a bit longer. 3. I rinse the piece and brush it with steel brush. This will make the process faster. I used a powerwasher on those bigger pieces i did. Powerwasher is good way to clean them, but not so handy on smaller pieces. 4. I sunk the piece again in mixture for next 24 hrs or so. Usually these 2 baths have done the trick. If not, i repeat the rinsing and bathing the piece. 5. I rinse the piece again and if i am happy with the result, i make sure its rinsed properly and dry the piece with a heatgun. The heat will neutralize the acid. After it is dryed and cooled down, i spray primer on the piece. If you leave it after drying it, its starts to get rusty again. I hope that helps.
I have heard that the cast metal and hardened steels like spring steel are a big no no with citric acid. The cast metal will be fragile after the bath and hardened steels will disapear in the long run. I have no experience with cast metals and citric acid, but i have some with hardened steels and citric acid. I had a set of headliner bows, i throw them in the mixture bath and this is completely my own fault what happened next. I forget them in the bath for few weeks and when i picked them up from the tank, they were completely ruined. They were really thin, a lot of material from the bows had disappeared. They werent that rusty, that there were almost anything left of them. So only explanation for that must be that the bows are hardened steel originally. If someone wants to try what happens for shits & giggles, go ahead. But i am not trying that shit anymore, lesson learned Well, i have to find an another set of '49 to '51 Ford tudor headliner bows somewhere..
@Finnrodder You have a very strong batch if the hood and doors were cleaned of rust that fast. No wonder your headliner bows whittled away. I put seat frames with springs in my tank for a week or two depending how rusty they are. Sometimes longer with is often. No problems thus far. @Inked Monkey You should not have a problem with your springs. If concerned, check them daily. But that`s if you are paranoid. I have an item that`s been in my tank for 9 months. It`s an old shoe shop machine. Will be getting it out shortly. it`s heavy and I kind of forgot about it. Got 100 pounds in yesterday for my tank. Won`t use it all at once. My old batch is 4 years old.
Since the citric acid does its work from the outside of any part, it would seem that thick heavy items should be fine in most citric acid bathes for a short term.......then resubmerge if they need a little more derusting. Thinner items obviously should be checked after a few hours and then proceed from there.
Its not that strong, i use 5% mixture. Some people have suggested that 7% is a correct mixture and other say that 3% is the most effective. So i have used something between them, that 5% has worked fine with me. I have also heard that heating the mixture will make it more effective, but the process has been fine without any extra heat. Like i said, that headliner bow failure is completely my own mistake and its my only bad experience with citric acid. It was a huge WTF moment, when i get them out of the tank. I noticed that i havent get rid of those yet, i dug them out of the junk pile and took a pic. The thicker one is near std size and those welding wire looking things are what are left of my headliner bows.
Does anyone know if the citric acid ruins fiberglass? I have some wood shipping "coffins" that I saved from work, with the idea of lining them with a layer of fiberglass to use for a citric acid tank and a neutralizer tank. They are a nice size for fenders and probably most doors, so they would be ideal if a fiberglass liner would hold up.
Just use a heavy plastic sheet such as thst used under coccrete home foundations Sent from my SM-G965U using The H.A.M.B. mobile app
Agree with treb11, use a black plastic dropcloth to line the box. I did that several years ago for an electrolisis setup. I figure someone could actually build a long flat rectangle and lay a drop cloth in it and do a frame. Then use the lumber for something else when done. Obviously you can't put things with sharp edges in it unless you suspend them so they don't poke the liner.
I started to do that, then I did the math. If I was in the spot to do all my frames it would have been OK. Without barrels to store the liquid for future us it wasn't worth it. I have the wood and plastic someone near want to do a frame party? I'm almost done blasting mine now. After re-reading here I did the math again. What I was setting up was 14' x 4' x 1'. It would hold about 420 gallons. Using 1lb acid to 5gal water it would take 84 lb. Using the 1 cup to 3 gal ratio it would be 47lbs of acid. That is a lot better than what I came up with before especially if I did the 4 frames I have sitting around along with all the other parts that would fit into it. By changing the shape to take the frame sitting on it's side and 2' deep It would take less but fewer other parts would fit. I am almost done blasting my frame so I doubt if I'll do this for now. I do have a large tank that will fit everything else.
Ok, I filled the block with white vinegar 2 weeks ago. Put an old waterpump on to circulate the brew and ran it each night til it was warm. I have drained the vinegar today and a mushy goo like baby shit has come out. Been flushing with the hose then a brew of baking soda to neutralise the acid, 10 minutes more flushing and now washing soda crystals in for a final soak. I would call it fairly successful ?
Ewww. Your engine threw up. I bet it feels better. I use citric acid. Good stuff. But I like to also sandblast afterwards if I can. Take advantage of the benefits of both processes. The acid tank is easy, set it and forget it, and gets in every nook and cranny and pit. Then, just a quick sand blasting removes everything else, makes it super clean, gives it some tooth and no instant flash rust as long as it's kept dry. I'm seriously considering building a tank big enough to soak the WHOLE bottom half of my 53 Chrysler. If I actually do it, I'll definitely post a thread.
OK, winter is on the way. Does the citric acid help keep the water from freezing or is there something else that needs to be mixed with it ?
It will freeze. I use a couple stock tank heaters in my tank. Only the top few inches freeze when it gets real cold.
Ain't that a shit in the crisper! We had the same deal in our neighborhood, everything was wine and roses until some asshole bought the ground behind us 10 years ago. Stupid ass doesn't understand that water runs downhill, and is constantly bitching about rainwater runoff onto his precious property. I have half a notion to take my drop fertilizer spreader over there some night and write a little greeting in his pasture.
I looked on u tube and some farmer did some testing on some stock watering tubs. He was spending a fair amount of money trying to keep the tanks unfrozen......but we usually don't get as cold weather as he does. Said the heaters usually lasted a couple of winter's. I was thinking about just adding some antifreeze to the mixture. As long as it doesn't freeze solid it should be okay.........maybe?
The Jalopy Journal
