Parkerizing

[T. Cotten]

The real thing varied widely, as original parts show clearly in the attachment.

If all the parkerizing on a machine matches, it might as well have been rattle-can'd.

...Cotten

[gallen]

Parkerizing

T.Cotten
So what you are saying is that the color doesn't really matter?
Or there wasn't a specific color used by Harley or the different vendors.

[schmittm]

Gallen,

I tried to answer this question back on the first page of this thread. Final color is a combination of which parkerizing process you use and the alloy of the base metal you are coating.

Lighter, greyer, color results from using a zinc phosphate process and/or treating hardened steel alloys with high nickel content. As a general rule, the harder the alloy; the lighter the final color.

Darker, blacker, color results from using a manganese phosphate process and/or plain iron or low carbon alloys.

To determine what "color" the parts on your particular bike should be you have to do a little research about what was going on in the industry at the time the parts were made. Prior to WWII the motor company made most of its own hardware and finished most of it themselves, the most common process used at that time was the manganese phosphate method: dark parts. During WWII the War Production Board limited the availability of manganese so the industry switched to the zinc phosphate process: lighter greyer final color.

After WWII the motor company began going to outside vendors for their hardware, like Chandler Products in Ohio. The industry was also looking for ways to economize so they were playing with the "recipe" and the method, trying to come up with quicker and cheaper ways to parkerize stuff. The results of all this is a variety or assortment of different final color and appearance of parkerized parts. Like Cotten said; the parkerized parts on any given bike will not and should not match exactly.

The manganese process also produces a much coarser more porous coating, the zinc is a smoother tighter grain finish. A large part of the degree of protection provided by parkerizing is because this porous coating will absorb and hold oil on the surface of the part, displacing water, and keeping it from rusting. Unless you thoroughly rinse the acidic parkerizing solution from the part, completely dry it, and allow it to soak up some oil it will rust quicker than a bare metal part. The amount and type of oil retained by the part will also determine its final appearance. WD40 is still the best, by the way.

Summary:
Pre-WWII; generally darker parts with a coarser surface
War Production; usually lighter, smoother parts
Post-War; wide variety, even on the same machine

I also mentioned that you should not vary the immersion times trying to achieve a different color. The solution is acidic, it will etch your parts and change their dimensions if you leave them in the bath longer than neccessary. If you don't believe this throw a sacrificial nut and bolt into your bath and leave it there for a while, rinse it, dry it, oil it, and see how sloppy the nut is when you thread it on, if it will even stay on the bolt! When the parts stop fizzing, take them out and rinse them immediately, usually about 10 to 15 minutes is all it takes, less if you increase the temperature.

If I'm wrong about any of this I'm sure somebody will straighten me out.

mike

[gallen]

Parkerizing Color

Mike,
I read your first posting. This one I think does the trick.
I just have to find some pictures of a 47 Knuckle that is done pretty much original and go from there. I have found a place that sells both black and gray solutions.
Thanks again,
George

[Bill Pedalino]

Cad Plating

For those located in and around the Long Island, New York area - Nassau Chrome, Inc. in Mineola New York does excellent Cad Plating. I used them during my dark years (1960's chopper years) and I'm currently using them for my '53 Panhead and '47 Knucklehead and I'm extremely pleased with their Cad and Chrome plating. Boy - have prices gone up !!

Bill

[schmittm]

I'll make a couple more comments and then I'll shut up

Don't try to disguise hardware that came out of the parts bin at the local home supply center, it is almost always zinc plated. Parkerizing only affects iron and iron alloys, it won't touch something that has already been zinc or cad or chrome plated unless you COMPLETELY remove any and all previous treatments.
It simply is not worth the trouble, buy the Colony stuff already parkerized.

As has been said earlier, don't worry about trying to get everything to match, it won't. The only things that should match are parts that came together as sets to begin with, like a set of timing cover screws or a set of motor mount bolts.

Mismatched color will even occur on the same object, a perfect example is the clutch operating arm in the picture that Tom posted above. If that piece was thoroughly bead blasted, degreased and parkerized as a unit there would be several different colors on the same piece; the body is stamped cold rolled steel and would probably be a dark shade of grey, the rivets may be softer and come out a darker color, the weld material is a different alloy altogether, no telling what color it would be, and finally the grease zerk was more than likely cad or zinc plated so it would probably look spotty depended on how well it was bead blasted.

Take a close look at commercially parkerized hardware, if you spread a big assortment of parkerized Colony hardware out on the bench you will seldom find 2 colors that match unless they came in sets. Most times the nuts don't even match the bolts or washers in the same set, and items from similar sets won't match from order to order. Its no big deal, the bikes were assembled from similar assortments when they were originally built.

The only important thing is to protect the part from rusting. Thoroughly rinse, thoroughly dry, and give the parts enough time to soak up plenty of WD40. Re-treat with WD40 as needed, if the parts have that "sparkly" look they are dry, no oil, and they are going to rust.

mike

[hogluvr]

Excellent advice guys, this is the kind of information I was looking for!!

[cmoon]

Parkerizing is not the worlds best rust barrier. To help with this, I was told after removing each part from the boiling parkerizing solution to then dunk each one in hot oil. I found a small pan of hot, around 250 deg., automatic transmission fluid worked very well. You will be amazed at how much boiling occurs while all the remaining water in the pores & holes of the parts is removed. Be careful not to overheat the oil. Smoke is your first indication that it's too hot! Synthetic ATF can take a bit more heat.
If you want something a little thicker than ATF as a final rust barrier, try to get an areosol can of CRC SP-400. It's sort of like hi-tech cosmoline. Spray it on and let it dry. Here is the info on it: http://www.crcindustries.com/ei/cont...x?PN=03282&S=Y

It's been a couple years and no rust what so ever on my parts.

Good luck!

[Rod K]

parkerizing

CRC is a good product...If you can't find it in your area, another good one is LPS#3. Both of these can be applied at any time to keep the parlerizing looking like new

[PanHDBud]

Moose, I found Parkerizing.com on the web and bought black solution made for Harleys and Indians. Parkerized my parts and was suprised how easy and great they came out.
Bud