© 1998-2008 Joe Weaver




The subject of this edition is the use of Eastwood's Blackening System to restore the look and protection level to parts and fasteners that originally had a black oxide finish. The bolts used in this edition are the ones that bolt on the structural cross member under the transmission which is used on convertible Falcons. As can be seen in the photos, these bolts with integrated conical washers are quite unique. I had tried to replace them, but was unable to find exact, or even suitable replacements (other than standard zinc plated bolts with large zinc coated washers and lock washers, which I thought would look pretty cheesy and probably wouldn't do the job as well as the original fasteners). Other than being very greasy with light surface rust, these original bolts were in generally very good physical condition, with only some minor physical damage to some of the heads and very light pitting on the conical washers. The threads were in excellent shape.

As will be seen below, these bolts were dipped in the blackening solution, but the solution can also be brushed on larger items if necessary. All parts to be blackened must be steel or iron. The system will not blacken stainless steel, aluminum, or any plated or otherwise coated steel or iron part. Only ferrous metals will blacken with this system and they must be completely stripped of rust, paint, old blackening oxide, grease, oils, etc., until only bare metal is exposed. As mentioned in part one of this edition, the blackening process actually oxidizes the surface metal and seals it with a coat of its own relatively stable oxide which is quite hard and fairly resilient. This system also uses a sealer solution that the blackened part is dipped into or coated with which ultimately determines the corrosion resistance and good looks of the part over time. I discussed this procedure with a metallurgical engineer friend and need to pass along his thoughts. First off, black oxidization is certainly more stable than plain rust oxidization. However, when viewed microscopically, the black looks like a bunch of tiny black balls stacked on top of each other. Without some sort of sealer, water would seep between the “balls” and get to the bare metal and cause rust oxidization. Thus, this system uses both a black oxidizer, and a sealer to keep the metal corrosion resistant.


I first degreased these bolts using solvent (paint thinner also works well) and then used a media blasting cabinet to strip these bolts to bare metal. I then degreased them one last time with acetone before blackening them.

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Before and after views. The bolts were very greasy and dirty with gritty road grime. The left photo shows them after being degreased with solvent and dried with compressed air. The right photo is after the process is complete.


This is one of the bolts after media blasting & degreasing, ready for blackening. Items for blackening must be blackened immediately after stripping or the "flash rusting" that occurs from humidity in the air will interfere with the blackening process and the finish will not look as good, or perform as well as designed. Don't strip parts today and plan on blackening them tomorrow. Wait until you are ready to blacken them before you strip them. The blackening process is very quick (about five minutes) so it can easily be done right after stripping & cleaning.


As mentioned above Eastwood's system consists of two solutions. The blue solution on the right is the blackening solution. The orange solution on the left is the sealant. The blue solution comes as a concentrate in a separate bottle and is poured into the container shown above. It is then diluted with distilled water till it is two inches from the top of the container. As seen in the photo I marked a spot two inches below the top for ease in setting the system up. The sealant comes ready to use and needs no dilution.

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For several days before actually using the system I considered the best way to dip parts in the blackening solution. Dipping them while holding on with some sort of tweezers or pliers wouldn't work since the place where the part was gripped wouldn't get any solution on it and therefore wouldn't blacken. I thought of suspending the parts with a wire but also worried about the wire blocking complete solution coverage. I looked at small kitchen-type strainers and even small fish nets from an aquarium store. I finally settled, believe it or not, on an old plastic Kraft grated Parmesan cheese container as seen above. It fit perfectly onto the opening of the bottle provided with the blackening system. After washing it in the dishwasher, I drilled holes all over in the sides and bottom to make a sort of "strainer basket".


This shows the stripped and cleaned bolts in the new "strainer basket" and better shows the holes drilled in the sides and bottom.

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The left photo shows the bolts about to go into the solution. The right photo shows the bolts completely blackened after just 30 seconds in the solution (Eastwood says 20 to 60 seconds depending on the part). To make sure each bolt got full coverage, I jostled the bolts around inside the container during blackening.


After blackening, the parts are rinsed in distilled water for 10 to 20 seconds (again jostling them around while in the water).

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The parts are then dipped in the sealer for one to two minutes (again jostling them around occasionally while in the sealer).


When the parts come out of the sealer they are left to dry with no rinsing. Eastwood says it can take anywhere from one hour to overnight to dry depending on the part, the temperature, and the humidity. These bolts took about five hours to fully dry at about 70 degrees Fahrenheit (20 degrees Celsius) and about 60% humidity with a light breeze blowing on them (I put them by an open window in the shop, both for the help of the breeze in drying them and to allow the slight fumes from the sealer to escape outside during drying).


These are the finished product. They look and feel like brand-new black oxide bolts (the slight variance of color on the finished bolts in these photos is due to the high level of JPEG compression algorithms in the digital camera I used -- the bolts really have a uniform satin black appearance just as new ones do). Of course, any damage to heads or other parts of bolts, nuts and screws that was not taken care of prior to blackening will still be there, and the underside of several of these conical washers have minor but visible pitting from the previous rust. But they should now function as well as they did when they were new, which means they should last at least another 45+ years. Again, this is a lot of work when compared to just buying new bolts. This whole process, including degreasing, media blasting, and blackening took about two hours -- for just six bolts. There are hundreds of nuts, bolts and screws for this car and if I took this amount of time to restore all of them this project would drag on a lot longer than I want it to, which is why I decided to replace all the fasteners that I could. However, if you would need to replace some of your original black oxide fasteners or other black oxide parts with something less desirable than the stock item, and they are in generally good condition, then this blackening system may be just the ticket. If you process a lot of fasteners and/or parts it will even save you money over buying new replacements. I've spent over $150 on new replacement fasteners for this car. However, right now I am anxious to get this project finished, so if I can save time buying new fasteners I will most likely do so. But I am finding that there are many specific fasteners (such as these shown here) and other small parts that originally had a black oxide coating that no one is presently reproducing so this system gives me a way to still get the job done, and done right.

Discussion & Procedure



Restoring Nuts

Bolts & Fasteners

Part 2

This is the end of the Restoring Nuts, Bolts, & Fasteners Edition


Feel free to save this page to your computer for your personal use and future reference--no other use is authorized without prior written permission from me. All illustrations from the 1964 or 1965 Falcon Shop Manuals used pursuant to permission granted by Ford Motor Company. Disclaimer: This site is not intended to instruct or teach anyone in proper or safe methods of working on or maintaining any type of vehicle or use of any tool and the author takes no responsibility for the use of the information contained herein.

If you have comments or suggestions, email me at joe@joesfalcon.com