How to create faux antique black screws, nuts & bolts - Embedded.com

How to create faux antique black screws, nuts & bolts

I don’t care how sophisticated is the embedded system on which you're working; sometimes you need more than electronics and computing hardware and software know-how to get the job done.

Consider the fact that a lot of my projects have a Steampunk or antique look-and-feel. In the case of my Bodacious Acoustic Diagnostic Astoundingly Superior Spectromatic (BADASS) Display, for example, I went for a dark-wood and brass motif as illustrated below.


(Click Here to see a larger image. Source: Max Maxfield / Embedded.com)

Actually, although this ended up looking rather luxurious, it was relatively inexpensive to build (so long as you don’t count the inordinate amount of time I put into the little rascal). The main cabinet is formed from unassuming plywood that's been stained, while the “brass panel” is humble hardboard that has been painted to look like brass. The acorn nuts are only there for show, while each of the tri-colored LED assemblies is formed from a brass washer and a plastic Fresnel lens.

By comparison, in the case of my Cunning Chronograph, I opted for an ebony-looking cabinet. When it came to the back panel for this little beauty, I used cheap-and-cheerful 3/16″ thick plywood. Once again, however, a touch of stain makes this look like a million dollars.


(Click Here to see a larger image. Source: Max Maxfield / Embedded.com)

I really like the elongated air holes around the edge of the back panel — I don’t know why, but I think they convey an “I'm an antique” look right there. And then we have the pattern of holes in the middle that present a Morse code realization of a rather apposite quote from Dr. Seuss (see also Multifunction robotic arm lends a hand and How did it get so late so soon?).

Unfortunately, I ran into a little snaggly-poo when it came to attaching the back panel to the main cabinet. The regular Philips-head steel screws I had to hand look positively garish against the dark wood. What I wanted was flat-headed (counter-sunk), slotted (not Philips), 5/8″ number 6 wood-screws with a black oxide finish.

Is this too much to ask? Well, apparently so, because — although I tried all the usual suspects (and some very unusual ones) — I couldn’t track the little scamps down anywhere. Eventually, my inventor chum Brian LaGrave pointed me toward a specialist distributor who grudgingly acknowledged that they could supply these screws if forced to do so, but they wanted to charge me around $1 a screw — not including shipping and handling — and I need 48 screws to hold the two back panels (I know this is overkill, but they look so good!).

Brian then came up with an alternative approach, which is to purchase regular steel screws (they can be zinc-coated, but you can't use stainless steel) and blacken them myself using something called Gun Blue. This sounded like a jolly good idea, so I bounced over to Amazon and purchased a small bottle of this miracle solution for just a few dollars.

Now, I didn’t know how long to do this for, so I chopped the bottom off a discarded plastic water bottle, dried it out, and added 10 zinc-coated steel screws. Then I set the timer app on my iPad running at the same time as I covered the screws with the Gun Blue solution.


(Click Here to see a larger image. Source: Max Maxfield / Embedded.com)

My original plan was to pull a screw out every 30 seconds, let them dry on a piece of kitchen paper, and to compare them to determine the optimum time for immersion in the solution. In reality, after only 30 seconds had passed, all of the screws had turned jet black.

If the truth be told, I was tempted to abort the experiment at this point, but “If we don’t have a plan, we're no better than the French,” as the old saying goes, so I plowed on regardless. At the end of the day, I've decided that I'm going to go with a 60 second immersion. The only thing that seems to change when you leave them in the solution longer (apart from weakening the solution, which you can reuse later) is that more of the black stuff rubs off on your fingers.

You can see this reflected in the image below — the screw on the left was in the solution for only 30 seconds; the screw in the right was in for five minutes, with 30 second increments between adjacent screws. The amount of block stuff that comes off the screws is proportional to the amount of tim ethey are submerged in the solution.


(Click Here to see a larger image. Source: Max Maxfield / Embedded.com)

One thing I neglected to do for this test was to degrease the screws before covering them with the solution. The oils on one's skin can mask the screws — this is really apparent when you look at the screws closely — as can any oily residue that was left over from manufacturing.

But what should we use as a degreasing agent? The first things that came to my mind were denatured alcohol, rubbing alcohol, turpentine, acetone, and isopropyl alcohol. The problem is that I really don’t know what the differences are between all of these, and I have no idea which would be best to use as a degreasing agent.

Do you watch the TV reality show Pawn Stars ? One of the authentication experts featured on the show is Mark Hall-Patton, who is affectionately known as “The Beard of Knowledge.” Well, my chum Ivan, whose office is in the next bay to mine, is our building's “Mustache of Knowledge” equivalent, because he knows amazing amounts of stuff about amazing amounts of stuff.

First, I asked about denatured alcohol, but Ivan says he isn’t a fan. I know what he means — I don’t like the taste either. (Before anyone runs off to try this for themselves, and on the basis that we live in a litigious society, we should note that this is a joke; the government adds poison to denatured alcohol so they can keep the price down without giving us an excuse to drink it).

The bottom line is that Ivan says most of the aforementioned alcohols aren’t as good at degreasing as one might hope. He suggested submerging the screws in a bowl of hot water with a drizzle of Dawn washing up liquid, mixing everything up, and then rinsing them off. I might then pass them through a quick bath of isopropyl alcohol (since I have a bottle here in the office) and leave them to drain on some kitchen towel as an aid to ensuring they are 100% dry before dropping them in the Gun Blue solution.

I tell you, I'm kicking myself that I didn’t think of doing this earlier because it would have saved me a lot of time and money. Take my Pedagogical and Phantasmagorical Inamorata Prognostication Engine, for example. In the case of the two panels shown in the prototyping jig below, we see three black dome-headed, slotted machine screws holding the main “General Gruntlement” meter in the upper right-hand corner, and another six smaller screws holding the “Full Moon” and “Blue Moon” meters in the bottom panel.


(Click Here to see a larger image. Source: Max Maxfield / Embedded.com)

There are a few more machine screws of various sizes scattered around the rest of the machine. All of these screws put together are relatively insignificant in terms of numbers, but the time and cost taken to track them down is out of all proportion to their quantities, not the least that you typically have to buy them in boxes of 100.

If only I'd known that I could have purchased their steel equivalents — which are cheap, plentiful, and widely available — and then blackened them myself. Ah well, we live and learn; I only hope that next time I learn what I need to know before I splash out my hard-earned cash. How about you? Have you ever ended up purchasing something whose price-tag made your eyes water, only to discover that you could have created something equivalent much cheaper?

5 thoughts on “How to create faux antique black screws, nuts & bolts

  1. “Carrs also do a variety of chemical blackeners for different metals here in the UK, however we find gun blue (available from any maker)considerably cheaper for steel. I find the brass blackener can “shed” small areas during treatment leaving little bras

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  2. “To degrease the screws prior to blackening them, try some “Supertech” brand non-chlorinated Brake Parts Cleaner (A more expensive alternative is CRC's “Brakleen”). Both of these products are available at Wal-Mart, and both are excellent degreasers.

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