Pre dip black parkerizing post dip black dye parkerizing.

I have tried hot dip black oxide in the past on guns and bayonets, worked ok but was very temperamental and dangerous. I have also seen recent black oxide methods that seem to give a brownish purple finish, no where near a black finish of black oxide, have they changed the formula. My favourite finishing is parkerizing and it would be great if I could produce this in black, the manganese is not black enough. I was reading an old milsurps post where it showed a wartime note from one one of the small arms factories stating that the parkerizing finish was not dark enough and they recommend using a black dye for a black finish. Anyone know what this process was and the type of dye used. Somebody mentioned that they used boot polish but I am sure this would not be durable if solvents were used to degrease the gun at a later stage. I also saw that Brownels and Midway use a pre black park dip, has anyone used this and could I get this in the UK. It's a shame the chemical formula for parkerizing couldn't be changed to produce a black.

One method is go to an artists supply store and buy a tube of grease paint. Do not buy acrylic paint. It has to be the old fashioned grease paint.
Dissolve a small quantity of the paint in some light machine oil like 3-in-1 oil.
While the part is still hot from the parkerizing bath, submerge or quickly brush on the tinted oil. The part has to be hot.
Experiment with a small part to get the results you're looking for.

We just added steel wool to the bath and while it consumes the steel wool, it turns the park black.

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Originally Posted by browningautorifle

steel wool

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Degreased or does it matter?

We never found it mattered. It got consumed in short time. You could boil it if it bothered you...we didn't. We also used 0000 fine...

I usually use steel wool for my manganese park mix, I was wondering if anyone has tried using iron powder as opposed to steel wool. I believe iron phosphate (parkerizing) gives a blacker finish, so I thought an iron content would be darker.

I've never tried it but Iron filings are one method I've read about, I also have read that if the item is dropped into engine oil (Possibly well used with carbon deposits) sooner rather than later then a darker appearance is obtained. The Americans tend to like a grey with a green tinge for their US weapons and like to add cosmoline to the finished product.

Pre Dip

If it’s NOT removed before the parts go in the park tank, what you are calling “pre dip” is probably an activation solution containing titanium salts. It’s commonly used here in industrial phosphating of oilfield parts.

Iron Phosphate

Manganese and zinc phosphate coatings are much more rust resistant than iron phosphate. It’s not really suitable for this application, oil dip or spray. It is good for items that will be painted.

The acid and metal reaction is going to produce some iron phosphate, but you want as little as possible. What you’re looking for here is a solid manganese or zinc coating.

Porosity

The phosphate coating is porous, like a sponge, and soaks up oil, paint, etc.

It’s the oil or other material that provides the corrosion resistance.

With manganese and zinc coatings the oil also acts as a lubricant.

Post dip black dye

Instead of using a dye, you can use “Cold black oxide.” It is not really an iron oxide coating. It’s a copper selenium deposit.

Anyone know what chemical makeup is in the Brownells pre dip black parkerizing, can't get it here in the UK.

I don't know what's all in Brownells surface activation solution.

Look for something containing titanium salt or salts, or Jernstedt salts. It's probably potassium titanium fluoride (dipotassium hexafluorotitanate). It might also be listed as a grain refiner.


[edit]

Here you go. They ship to the UK. Look for Great Britain in the drop down when you checkout.

Manufacturer of DuraCoat Firearm Finishes: Black Dip Parkerizing Pre-Treatment

Thanks for all the info very useful, In the next couple of months I will do some experimenting hopefully with some interesting results.

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Originally Posted by Vincent

I don't know what's all in Brownells surface activation solution.

Look for something containing titanium salt or salts, or Jernstedt salts. It's probably potassium titanium fluoride (dipotassium hexafluorotitanate). It might also be listed as a grain refiner.


[edit]

Here you go. They ship to the UK. Look for Great Britain in the drop down when you checkout.

Manufacturer of DuraCoat Firearm Finishes: Black Dip Parkerizing Pre-Treatment

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I would have bought some pre dip black solution but at over $100 odd dollars for shipping just a quart of solution it looks like I will have to look else where. Anyone know if I can get it in Europe.

Try Henkel.

[edit]

Fixodine M is another name for BONDERITE M-AC M. It's for manganese phosphating.

Henkel also sells several Fixodine products for zinc phosphating. Look under Surface Treatment Conditioners. http://www.bdi-usa.com/FileUploads/CMSFiles/Surface%20Treatment[0].pdf

Well I contacted about 15 companies here in the UK and not one reply. Fantastic looking web pages but it's like dealing with Neanderthal man who just discovered a jet aircraft. Looks like I will have to save up on the postage or find another European country that would stock more Brownells or Midway products than Brownells UK that hardly stocks anything like Brownells USA. Any suggestions to get my hands on this pre dip solution?

PS, much appreciated Vincent for your help.

I did some digging. It looks like the DuraCoat Black Dip is just an acid bath, a mixture containing Sulfuric, Phosphoric and Hydrochloric acids. There are no Jernstedt salts listed.

I had a look at Brownells MSDS sheet and found that Hydrogen chloride and Potassium Antimony Tartrate is used in the mix, not sure how the chemical reaction takes place or what its meant to do or how toxic it is, anyone know or if there are other ways. I was reading that the Black phosphate process is the most overlooked functional metal finish process around today. I had a chat to a Canadian company and they are looking for an agent to set up in Europe that sells the black phosphate process etc., anyone interested I can pass on details.

Has any members on this forum used this pre dip black, just wondered what you think of it and the finish. I have had finishers this side of the pond say its just a fad someone has managed to create a bit of a niche that really isn’t there!

I am confused. :confused: Are you doing Zinc or Manganese phosphating? :confused:

I have both zinc and manganese. The pre black solution seems to be used for the zinc process.

You might give ILVE Chemical in Istanbul a call. See if they will send you a small test sample.

Topfmine,

I don't use any pre dip, but the item will need to be cleaned to a high standard and after this I bead/sand blast it, for the dark Manganese finish I use fine wire wool as BR mentions, don't waste your money on solutions etc, two main ingredients can be bought on ebay, as for water I now collect the water from the drain on my condensing boiler.

The link below is when I first started to experiment, there is a formula near the end which I now use but still add the wire wool.

I did a few bits for a forum member some time back and one part I couldn't get a nice finish on, could not work out what was wrong until I was finishing another part, it turned out the part was resting on the bottom of the tank so was taking more heat than normal.... lots of head scratching but eventually got to the bottom of it.

Home DIY phosphate/ parkerizing process

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Originally Posted by bigduke6

was resting on the bottom of the tank

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All covered in the crap...so no clean finish.

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Originally Posted by browningautorifle

All covered in the crap...so no clean finish.

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Kind of Jim, it was a bayonet and the edge was touching the bottom, the rest looked ok but the blade ..... it turned out the owner didn't want the blade doing anyway and happy with just the sand blasted finish on the blade.....

Kind of came out covered in scale?

I have seen stove black used to darken the finish. It's a brush on affair and a hair dryer helps it to take a set.

Many thanks vincent for the info, I have tried to contact ILVE but have not heard back yet. I did read on other forums that those who pickled the part with hydrochloric /acid mutric acid the finish turned dark using zinc phosphate, in one case a 1911 turned black. Usually when using zinc phosphate the colour is even but using manganese the phosphate picks out the temper of the steel. This 1911 was an even black all over. I have notice this darker zinc finish when picking with hydrochloric acid especially If the finish has not been bead blasted, I sometimes pickling to get rid of pitting that cannot be removed by blasting. To get a black I wonder what the other chemical would be.

You should be able to get jet black using manganese without much trouble.

Over time the free acid goes up and the result is a lighter coating. If nothing is done, the free acid will eventually increase to the point where it consumes the coating and nothing is deposited on the surface. The surface will look gray, but it’s just acid etched.

To get it to work again you need to bring the free acid level down. Adding steel wool or scrap steel will use up the acid. The problem with doing that is you end up with a lot of iron and it ends up in the phosphate coating. It looks black as well digger’s a___ , but it is going to rust. And when you think about it you have been putting parts in the tank….. adding iron. So there should be plenty of iron.

You can test a small amount of your solution by putting it in a glass and heating it in the microwave. Then add a little disodium phosphate to bring the acid level down. Dip a test part in it. Add a little more disodium phosphate if needed. It shouldn’t take much in a glass. If you get a good black result, add disodium phosphate to your tank. If you don’t get an improvement, try adding acid. It’s unusual for the acid to be too low but it can happen.

The pre dip MSDS shows <1% Hydrochloric Acid, <1% Phosphoric Acid, 10-30% Sulfuric Acid by weight. pH: < 2.5

So remove 250 ml from a liter of deionized water. Add 230 ml Sulfuric acid, 10 ml Hydrochloric acid and 10 ml Phosphoric acid to the remaining 750 ml. Remember, always add acid to water, NOT the other way around. Adjust from there.

I am going to test it tomorrow. Will let you know how it turns out.

I should add that most types of stainless steel are attacked by sulfuric acid when it’s in intermediate concentrations. So you should NOT use a stainless steel container for this.

I am surprised acids, Parkerizing solutions, etc, are available in the UK. With all the legal restrictions there I thought they would be verboten.

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Originally Posted by Vincent

I am surprised acids, Parkerizing solutions, etc, are available in the UK

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Acids are available but never seen any parkerizing solutions here. Be interesting to see the pre dip results any chance you can do an item with and one without?

Yes. I will do that.

Attachment 61835

This was a 15 second dip in the sulfuric mix. Then only a short time in the Parkerizing tank. I wanted to see if it changed the color of the substrate. It did.

Attachment 61837Attachment 61836

I did these parts for a friend. Couldn't find the thermometer so I had to guess at the temp.

Got some nice crystals. Gray is normal. Turns black when coated with clear oil.

Attachment 61838

I didn't sandblast or clean this bit of Sterling tube before putting it in the dip. No surprise it came out blotchy.

There's certainly a change. Did you wash off after the 15 second dip or dunk straight from the tank, just wondered if there would be a difference with the crystallization ie smaller. I think but not sure you rinse the part on the instructions on the original solution before you dunk in the Parkerizing. What Parkerizing did you use Zinc or Manganese.

I didn’t rinse the parts. Just put them straight into the tank while they were still fizzing.

The crystals grew bigger the longer the parts were left in the tank.

It’s industrial manganese phosphate solution. The plant where it’s mixed is not far from me.

You should be able to find the acids to mix your own pre dip. Our local auto parts shops sell “battery acid.” It’s replacement electrolyte for lead acid batteries. The concentration of sulfuric acid is slightly higher than in the pre dip mix. http://www.batteryweb.com/downloads/ScholleMSDS.pdf Hydrochloric acid and phosphoric acid should be readily available in the UK. They are used in lots of household products.
Household Products Database - Hydrochloric acid
Household Products Database - Phosphoric acid

Many thanks vincent for your help and information I will certainly be looking into having a go at making my own solution.

You are welcome. Try it with zinc Parkerizing and let us know how it does. I would be interested in the results.

Thanks for the tests Vincent certainly a big difference, maybe pre dip is the way to go..... will try a few small test bits when I,m home.