Anyone done Manganese Phosphate at home?

[Tony Wells]

I don't mean Parkerizing, although it is similar, but done with Manganese Dioxide in the phosphoric acid. It's a much darker coating than Parkerizing almost black.

I used to do a lot of Zinc Phosphate, years ago, but the shop that I worked in at the time got out of the business a long time ago. I know of a coater over in Bossier City, but I don't want to ship this batch of parts out. I would rather do it myself. I have the heaters, but have to come up with some sort of tank system. It takes 5 tanks: Caustic (for degreasing), Rinse, Phosphate, Rinse, and finally Oil. The parts I need to phosphate are about 35" long, and tubular. There are some smaller pieces also, smaller than a hand. The two main tanks (Caustic and Phosphate) have to be heated to about 190f (88c), and have to be non-reactive, like stainless or plastic. I was thinking about using heavy duty trash cans, but today I checked on the materials' properties, and discovered that some plastics actually melt at not much higher temperature. I don't want to invest in stainless yet. If I get more demand I will, but not for this order.

Thoughts anyone?

 

[Tony Wells]

I'd rather capture the rinse than just let i go on the ground, so I was thinking of using tanks. I could probably get by this time though. And I could spray them with oil after the final rinse. It's just really important to get 100% coverage with the oil, and one of these parts is 26" long with a 13/16" hole thru it. Not sure about spray in the hole, but I cold swab it a couple of times.

 

[Highpower]

I would love to be able to do it at home myself, but I don't have the room. Also don't need the fumes rusting up everything in my shop.
Alas, I have to send my parts out to be done professionally. But I have seen some pretty interesting "tank" set-ups made from large diameter PVC pipe that was split down the middle with the ends capped, and used horizontally. That, or a smaller diameter PVC pipe used vertically with a water heater element in the bottom.

Of course if money were no object..... http://stainlesssteelcreations.net/parkerizing-products.html :biggrin:

Once you are up and running, let me know. I can keep you busy with work.... :lmao:

p.s.

It's been my understanding that you want to use distilled water for your rinse, to prevent spotting.

 

[pjf134]

Tony,
Have you looked into rubber lining at all? Some steel mills use rubber lined steel tanks heated for pickling steel. All the pickling tanks I have been around and worked on were plastic, rubber lined or acid brick and mortar. Most steel mills use 180 F. for there tanks. You have to make sure that the mat'l you use will take the acid and temp. required. If you have a plastic fab shop near you, give them a call and tell them what acid and temp you are using and they can pick a material in plastic from there corrosion chart, and also what percent of acid being used would be asked. For a one shot deal I would get a heavy wall plastic pipe then thread the ends and cap then weld the caps on and cut long way in half to get two tanks. Heat the tank too your temp. to try and see if it works OK. Polypro, pvc or cpvc should work for this as long as the plastic will work with the acids you are using. Just throwing some ideas out there. I did have a acid and material chart but I don't know where it is right now, but look it up on the computer should help.
Paul

 

[4GSR]

Tony,

You might look at your local tractor supply store. I know it's a different name up there, the one on the west side of Tyler. Look for a fiberglass trough, they maybe some kind of plastic now.

The place I worked at several years ago went this route, worked out quite nice. Used electric heaters to heat the solution, bath for cleaning, rinsing was done on the floor before they went into the solution, the rinse again, then a tank that had some kind of fine oil persevant. Of course, today, you can't let your rinse water go down the drain!

But as long as the waste is neturalized, baking soda works great, you can flush it down the drain! Atleast the chemist I worked with said you could. I'm not sure about that...Where I lived at the time, once neturalized, I just poured it out on the ground! Grass is still growing, no dead trees!

 

[Tony Wells]

Today I spied a couple of fiberglass water softener pressure tanks that are about 4 feet tall and 2" in diameter. I think I can get them for nothing. If so, I'll saw off the domed top and dress the edges. I have a couple of submersible heaters that were actually salvaged from the tanks I used to run at the old shop in 81-82. Don't remember the wattage, but they are 220 and about 3 feet long and 2 1/2" diameter. I have used them to cook some heads in a 55 gallon drum. Tide detergent is pretty aggressive at high temperatures. Takes paint right off. I just don't want to go 55 gallons right now, although I may have to unless I do get those fiberglass tanks.

Yep, we have a TSC...been there a number of times. You have a good idea there.

Rubber lining is under consideration as well. Then it doesn't matter what material I use......could build out of wood for that matter.



Thanks for all the ides so far, guys!

 

[pjf134]

Tony,
I forgot about fiberglass as I did some acid tanks out of duel lamanite (plastic liner with fiberglass mesh embedded into it). the plastic went into the inside and resin and mesh was added to the outside to give it strength. I am not sure about those softener tanks, but might work. A long time ago I made a pressure bluing tank for a old gunsmith out of PVC pipe with threaded end caps and a fitting for air, he would add bluing to the pipe close it up and add about 10 lb. air pressure to the pipe and put the pipe in a heated bluing tank and he said it worked real good. I am not sure if it will work on your stuff, but would be nice to know if it works better, since I never seen the finished product on the gun barrels.
Paul

 

[Tony Wells]

Well, I'm not doing gun barrels, but this process certainly would work on them, and some people do use Manganese Phosphate on firearm parts. What I am running is some tool housings for a coil tubing drilling motor accessory. A couple of the internal parts also require phosphate, so I'm building this setup for the whole batch. I have an old shotgun that I may do, just to see how it turns out. The blue on it is about gone, and I don't think it is really valuable. An old JC Higgins 12g bolt action.

I've uses fiberglass tanks with sulfuric and hydrochloric acids before, but can't remember any alkalines. I believe it will handle the caustic ok though. The phosphate is acidic, but phosphoric acid is not a strong acid, at the concentration I will be using.

 

[cjsamples]

Any idea if some of the larger diameter pvc pipes would work? Might need to use cpvc since it will need to be heated. I see you can get some up to 48 inch so maybe it might work.

Chris.

 

[Tony Wells]

PVC is in the running. I don't really need anything larger than 12" diameter at this point, but to cap it off and mount the heater off to one side is an idea that I have floating around if I can't find something more suitable.

Thanks for he suggestion!