Bluing, Bronzing, & Clear Coating
Bluing, Bronzing, & Clear Coating For Rodmakers
BB & CC, or, Oxide Finishes and Protective Boundaries
This ramble will be limited to cold bluing suitable for the home shop or low volume custom rodmaker’s shop. There are several points worth noting. First, the methods used to oxidize rod components typically rely on relatively weak, “consumer safe,” acidic solutions applied room temperature, or at best on parts warmed by hot, though not boiling, running water or heated preparatory baths; this is not a discussion of hot bluing which occurs when steel parts are immersed in an alkaline bath at high temperatures. Second, while the effect is visually similar to gun bluing, and while this effect is achieved by initiating and controlling an oxidization reaction on the surface of the metal, what follows is a discussion about oxidizing non-ferrous metals and thus is not identical to cold bluing as accomplished on steel parts in a firearms shop. “Gun Blue” may be a good visual description for the color effect achieved by the methods detailed here, but it is not a good description of the methodology or the physical result of the cold oxidization process. Third, the process discussed here is not primarily protective of the nickel silver or brass parts in the way that gun bluing (and oil) is protective of the underlying steel of a firearm; rather this discussion emphasizes primarily cosmetic, and traditional, oxide finishes for reel seats, ferrules, winding checks, hook tenders, and so on. Fourth, if you are interested in the chemistry of these reactions, seek elsewhere; I will be discussing practical, detailed, methodology, not the underlying chemical mechanics of oxide finishing reactions. Fifth, I will reference one readily available and reliable cold bluing solution, Oxpho-Blue, but I encourage you to try other oxidizers. In our shop, I use Oxpho-Blue along with other non-commercial solutions in successive applications to blue parts; the exact process is proprietary, but I’m happy to share enough information that you should quickly be able to discover the particulars that become your proprietary oxidization sequence. Our “bronzing” process is nothing more than a quick application of Oxpho-blue; no secrets, nothing proprietary, but we charge the same because it’s more finicky and less forgiving to hit just the right bronze-tones without going too dark. In no way should what follows be seen as the be-all, end-all discussion on this vast subject. I simply want to share a few notions that I’ve refined over the past two decades of rodwork in the Golden Witch shop. Although I will focus on oxidizing & clear coating fishing rod components for tackle makers and restorationists, because that’s what I do, the basic concepts explored here are applicable across a huge range of endeavors to include jewelry crafting and furniture making & restoration, specifically pulls, knobs, hinges, feet, and other functional and/or decorative metal bits. Once you develop a basic skill, it’s almost preternatural how often you’ll find the opportunities to use that skill in circumstances you never expected. My wife enjoys antiquing, and she abhors bright, lacquered, brass replacement hardware on vintage furniture. Her first question when she sees bright hardware against hundred year-old quarter sawn oak is to ask rhetorically: you can blue those drawer pulls, right? Yes, this skill is protean.
I am not an expert rock climber. These days I’m not an active climber. Water level was always – and remains – my preferred elevation. However, while I spent my young adulthood guiding whitewater river trips from a Perception Dancer in Pennsylvania and Quebec, and canoeing the backcountry lakes and rivers of Pennsylvania, Maine, and Minnesota, I did have the opportunity to climb, here in Pennsylvania and out west. Among other locales: Chiques Rock rising over the Susquehanna River, the incredible boulders at Governor’s Stables, Bellefonte’s quarries, and the hexagonal basalt columns of Devil’s Tower. Climbing seems the best metaphor for the bluing/bronzing process. I will often refer to this process as “oxide finishing” or BB & CC, for Bluing, Bronzing, & Clear Coating.
This isn’t going to be a Ramble in the sense of a casual ambling, comfortably paced. This is a formal ambulation, up a cliff, where each step is deliberate, precise, ordered, and goal oriented. If you screw up, you’re often headed back to square one, Snakes & Ladders style. Consider something like silk color selection within the ramble on silks to be more of a true ramble, meandering up and down a few gentle slopes, whistling the eponymous Zeppelin tune, on and on, hoping to stumble across something you desire particularly, but reveling in the freedom of the ramble regardless…and ramble on. By contrast, BB & CC, albeit offering less potential for real disaster, is more akin to a technical, multi-pitch climb and you’re the lead, precisely placing camalots, securing micro stoppers in the slimmest of seams, then wedging a hexentric into the only fat crack you’ve found for thirty feet, balanced with one toe on a dime-thin ledge, one decent foothold, three chalked fingers starting to sweat in a pinched stack too far to your left, but you stick it, clip in, and you’re off again. Breathing. Another step toward the top. Bluing can feel like this, not just the first time, but each time. The more serious you become about doing it right, the more care must be taken through each step of the process because you know how good it can appear, if each step is taken to the limit of your ability to perfect the step.
There’s another similarity between oxide finishing and climbing. Free climbers excepted – and my climbing buddy and mentor back then was a talented & daring free climber – there’s a safety rope involved with any ascent over a safe bouldering height. Whether you’re top-roping or lead climbing, that kernmantle rope, your harness, and an attentive belayer, will save your butt if you slip. Oxide finishing offers you something akin to a safety rope. You can polish off the oxide layer with a Sunshine Cloth and start over if you aren’t satisfied. If you accidently etch the metal, you can use fine polishing papers to swiftly and safely cut through the etched layer and thus expose fresh metal for a second shot at success. Second chances are critical to mastering most advanced skills. When I was first learning to climb, through Boy Scouts, the very first lesson wasn’t ascending. It was descending…otherwise known as rappelling. Here’s the most critical thing you learn when rappelling: to trust the rope, to know that the rope is your lifeline to second chances. I want you to learn to trust your rope. Choose a few sacrificial nickel silver parts and blue them over and over. Blue, then polish the bluing off. Do it again. And again. Intentionally etch a piece or two by ‘over-bluing’ and cut beneath the etching to begin anew. Your level of worry will fall off dramatically, allowing you to focus on good workmanship, once you trust the recovery process, the safety net, the rope.
I’m going to break the oxide finishing process into a series of steps. First I’ll discuss pre-polishing and cleanliness. Next, you’ll need to create jigging, both to keep your hands (skin oils) off the parts, and to protect your flesh from the acidic oxidizers; I’ll discuss a handful of specific wraps & jigs useful for typical rod componentry. Actually bluing (or bronzing) is the fun part, where your hard work pays off in seconds as the metal’s surface shifts from a brightly polished gold (brass/bronze) or silver (nickel silver), to a darkly oxidized surface, a surface which may retain the glow of the polished metal. This will be a good point to discuss flaws and fixes, i.e., how to know if something went wrong, because you can’t fix it if you haven’t been trained to notice and/or care about the errors, and how to fix those errors using your safety rope. Once you’ve achieved the oxide finish you desire, you’ll want to preserve that finish. “Ashes to ashes, dust to dust, everything falls to moth and rust” – true, true, but you can apply boundary layers which help to preserve everything you’ve worked to create. Finally, I’ll mention, without detailed instruction (for now), other options available to rodmakers for adding color & protection to their rod parts.
Pre-polish and cleanliness are just about “everything” with cold bluing. In order to pre-polish, you can either use a buffing wheel and rouge, or you can chuck a part up in the lathe (often on a mandrel of some sort) and spin the part under medium (gray) & fine (blue) 3M polishing papers…I only use the coarse (green) polishing paper if I need to remove a blem, such as minor “record marks” on the bottom of a reel seat that’s fresh off the machinery. Bluing is much like plating in that every flaw is accented, not hidden, so the better your part is before bluing, the better it will look after bluing and clear coating. If you polish with rouge, you must get the part incredibly clean afterwards or the wax that binds the micro-abrasives within the rouge can inhibit bluing. I use a jeweler’s ultrasonic cleaner, but a soft bristled “mushroom” scrub brush and plenty of kitchen dish detergent will do fine in most cases; brushing works on smooth surfaces and within most grooves; brushing is not ideal for cleaning out knurls, raised or recessed. If your brush leaves any marks on the metal, it’s not soft enough, especially considering that it’s lubricated with soap and water as you’re working the part. Once clean, dry the part – soft cotton is best (old, but clean, diapers), but a paper towel will work. The part must be rapidly dried through absorption, so that water droplets cannot dry on the surface, where residual minerals left behind by evaporation will leave water spots that are evident post-bluing. Once you think the part is dry, let it air dry for another 30-60 minutes (more for guides, which tend to hide water under the bezels), just to be sure there’s no hidden moisture. Your own fingers are the worst offenders once the part has been cleaned by scrubbing or in the ultrasonic. You must not touch the parts barehanded; always use the soft cloth for handling. If you accidently touch the part, use a sunshine cloth to re-clean it before moving forward.
Jigging & Taping.
Prior to bluing, you must create some sort of a jig to hold the parts. This can be a simple piece of bent wire (brass or nickel silver is best, e.g., ferrule pinning wire, but stainless steel is fine – I try not to use plated and/or carbon steel in my bluing solutions, i.e., don’t use bent paperclips or you’ll funk up your bluing solution pretty quickly). Holding parts like winding checks or some hook tenders on a wire loop is nice because if you jiggle the part in the solution, there’s no bare spot left from a single point of contact during bluing. If you use tweezers – necessary for some hook tender designs – you must blue, rinse, re-grip the other foot, then blue again to mask the bald spots resulting from the tweezer-contact points during the first immersion. For guides, reel seat parts, etc., you need to make a jig to hold the pieces. Often a sharpened pencil inserted gently into a guide ring is sufficient (don’t push so hard you crack the agate ring – it happens) to hold a guide for bluing and clear coating; unsharpened pencils or dowels built up with masking tape will fit reel seat parts. Parts like ferrules need the tabs and male slides masked off. Start with “invisible” tape for a clean edge, then overtape with masking tape. You can often just extend the tape that masks the ferrule tabs to make a little ‘handle’ for dunking the ferrules.
When I find the time, I’ll come back and extend this section by adding specific “how-to” notes for each type of common rodmaking component.
Bluing or Bronzing itself is fast and finicky. I’d dunk the part fast, because if you go slow then you’ll get a differential shading over longer parts. Swirl the workpiece gently, withdraw fast, and immediately neutralize the bluing solution. Swirling is critical because it destroys an otherwise static boundary layer of “used” bluing solution immediately surrounding your workpiece and ensures continual contact with relatively fresh solution during the few seconds of immersion. If you’re just doing one or two parts, you can neutralize through dilution…hold the part under running water for 60 seconds or longer, rotating to be sure it’s fully rinsed, then pat dry in your soft cloth. Again, dry through absorption not evaporation. Alternately, since bluing solutions are acidic, you can start by actively neutralizing in a bath made from baking soda, then rinse. If you’re doing multiple dunks in the bluing solution, be absolutely certain to rinse in warm or hot water and pat dry your components between dunkings. If you are also actively neutralizing the bluing solution in a baking soda bath, you don’t want to accidently contaminate your bluing solution with the neutralizing bath so rinse after the neutralizing bath before re-dunking. Be methodical. It’s ok to talk to yourself through the process, or make a checklist and tick off the steps. Eventually the process becomes second nature. Getting the color you want is all a matter of trial and error – it’s the part I can’t fully help with because I’m not operating in your environment. EVERYTHING bears on this process, not just your choice of bluing solution: cleanliness, temperature of the part (I like to work on “warm” room temp parts, not basement/garage temp parts), temp of the solution, temp of your rinse water which quickly effects the component temp on successive dunkings, speed of immersion, duration of immersion, speed of withdrawal, time from withdrawal to neutralizing, speed of neutralizing; the metal and even the specific alloy of a given metal effects speed and ultimate color. Practice. Learn.
You’ll learn more in a single day devoted to mastering this the bluing process than in a month of hours spread over decades. Pause in all your other shop duties and life responsibilities and play at bluing for a day. This is perhaps the most important tip I can share which applies to all new craft processes: turning your complete attention to a new task and/or tool for one or two full days is crucial to rapidly learning a new skill and embedding the know-how into your functional repertoire. I wish someone had told me this twenty years ago. I tended to flounder from process to process, good enough for now, move on, return, get a little better, or go backwards, forget, re-learn, re-live the frustrations, improve a bit….ad nauseum. Now when I buy a new tool that requires true learning, I don’t even set the tool up until I have a dedicated day. Some of the new tools acquired in the past year have required several days to master sufficiently –the hydraulic press, the TIG micro-welder. Both of these tools can teach me, through use, about their capacity for years to come, but the worst of the learning curve and all its attendant frustrations were behind me quickly. Because of this, both tools now earn their keep in the shop. It should be the same with bluing. Focus. Practice. Master the basics. You can explore the myriad details over the rest of your lifetime, but the basics will be yours after one continuous day of effort.
Shifting back to bluing…. Work and heat effect how parts blue. By “work” I mean that dead soft material oxidizes slightly differently that work hardened material. This is critical to understand because it effects the bluing of guides in particular, and enough that even an unaccustomed eye will catch the visual contrast. Imagine, the guide maker has made a frame, the forming of which required either a lot of hammer work or the smoother but stronger crush of a hydraulic press – and the bezel, depending on how that is made and applied has also received hammer blows, so both the frame and the bezel are, more or less, work hardened. But next the guide maker solders the bezelled stone into the frame, so the juncture of the frame’s wings and their point of contact with the circumference of the bezel have been heated to allow the solder to melt and flow. Now those points are a) certainly ‘heat treated’ in some sense, and b) possibly annealed depending on how much heat has been applied and how thin (think bezels) and low mass the metal object in question is. What you have here, as a simple artifact of the craft manufacturing process, is differential tempering. While this is a process intentionally applied to the cutting edges of various tools – and which can be the ruination of good tools if you happen to overheat the cutting edge while grinding the tool – the same process is merely accidental, yet unavoidable, when making guides. The polished guide will appear uniform in color – bright silver. But the oxidized guide will tell the tale, especially on that thin bezel. The color will be different closer to the solder joint. And, of course, the solder itself, which is a different metal entirely – usually a tin or cadmium-based alloy if soft solder or a silver-based alloy if hard, silver solder – will oxidize differently or not at all. Remember this phrase: Artifact of Process. There are some visual and/or mechanical effects which are a result of the materials and the process used to create an object, and you cannot necessarily “defeat” these effects, especially in this case, where you’re involved with surface oxidization. To be sure, in this same case, you can defeat the artifacts of process by plating an entirely new layer of metal on top of the existing substrate metal, and that’s why so many guides, vintage and modern, are chrome plated. Chrome is a mask, and I’ll be the first to admit that many guides wear it well. Chrome plate is historically appropriate. Many of the tens of thousands of guides in our vintage collection are chrome plated, and those date largely to the middle years between WWI and WWII. On my rods, I prefer the play of color and light, the mutability inherent in the oxide processes vs. the uniformity of chrome plate (bright) or black nickel plate (dark). Which doesn’t mean we’ll never plate guides in the GW shop; we have the equipment.
Capturing all this variety, in materials and methods, is where your notebook comes in handy. Start playing. I mean this in the nicest possible sense. The more you experiment with bluing, the better you’ll get. Generally speaking with Oxpho-Blue a quick 8-10 second dip, perhaps a hair longer, will give you the brown-tone oxide finish we market as our bronze oxide finish. To be clear, this finish is not actually a bronzing of the metal, it’s just got that vintage, bronzed look. If you like that, fully neutralize it, dry it, clear coat it. If you want a darker oxide finish, you’ll need to go back into the bluing solution again, and possibly again. The part will get darker and darker, shifting from that bronzy-brown to denser shades of blue/black. If I’m going for multiple baths on one part, I tend to start decreasing the immersion time on subsequent iterations. Ten seconds; six seconds; three seconds. Going dark can happen fast. The darker you get, the more likely you are to build up an oxide “powder,” a faint haze on the part that resists washing off in running water, but polishes off with the most gentle pressure of the rag. Once the haze if polished off, you should have a blued surface with nearly the same level of polish/reflectivity as what you started with on your bright metal. Bluing solutions are etching the metal at a micro level, so there is a diminishment of gleam, but it’s minor if you work fast and properly neutralize everything.
Bluing flaws. If your part emerges spotty – I mean really spotty, with bright spots, or barely blued spots, against a dark oxide finish elsewhere, then the part wasn’t cleaned properly. A drop of oil or wax probably masked the spot in the bluing solution. Re-polish and start over. If you can see your finger prints – and this is common – guess what? You touched the part after it was cleaned. Re-polish and start over or you’ll immortalize that fingerprint under the clear coat. The worst flaw to deal with is vermiculation. Literally, “eaten by worms.” This happens when you leave the part in the solution for too long and the micro-etching becomes macro-etching. It often manifests itself first as little speckles, like barely visible glitter, but can quickly grow to where it appears as little squiggly lines on a part, just as though small, but voracious worms had plowed through the surface, gnawing on the “good” blue oxide and exposing deeper metal. If there is visible vermiculation, you need to polish deeply. Best to use green polishing paper and work back up to fine paper. If you don’t get below the vermiculation, you’ll see it as soon as you re-blue. On a related note, some alloys just seem to make for spotty bluing, but this is at a minor level, a subtle unevenness compared to really great bluing. This might be a “flaw” in the way the alloy was formed, or, to put a positive spin on things, it’s another artifact of process. Alternately, some manufacturing techniques may stress the metal part in such a fashion that it blues oddly. Also, solder blues at a different rate than nickel silver, so solder joints on tube-stock ferrules and stripping guides are often visible as a slightly different shade of bluing – again, artifact of process.
Clear coating takes practice, too. I use clear, gloss, spray lacquer or enamel for most parts. Recently I’ve been using Rustoleum Crystal Clear Enamel. First, be sure the part is dry. That means after you’ve blued it and patted it dry, you let it air dry in a warm room. Next, blow off your part because any dust on the surface will be immortalized, and the part was just sitting still, air drying, and collecting dust. If you blow off with human breath, allow the “fog” of humidity to evaporate before spraying. Alternately, you can blow the part of with Bloxygen, which is more expensive, but imparts no moisture to the piece in the moments before you clear coat. Once dry and dust-free, you can spray on the finish. Again, temperature matters. If you have a cold part or a cold finish, the finish will go on thick and globby (at a micro level, but it’s ruinous). You need both the part and the finish to be about 72°F. Spray gently from about 8” (really, 6”-10”…depends on you, your spray can, and what works) and rotate the part in your one hand while moving the spray quickly & smoothly in full passes over the part, watching intently (hyper-observantly?), and the instant the little micro-droplets melt and meld into each other, stop. Be certain the entire part has been coated with an even sheen of finish, especially being careful that knurls and sharp edges are well coated. Now, you were already spinning the part in your “part” hand. Keep rotating the part. If you stop rotating, the finish will immediately pool to the lowest point as it’s setting up and you can’t remove that run or sag easily. Rotate for 60-120 seconds until you see that the solvents have largely evaporated You’ll know this has occurred when the finish “shrinks” and grips the part, almost looking like a finished part that I might ship…but it’s still tacky and hazy. This is really easy to see on knurled parts like winding checks and reel seat rings…the knurl looks wet and the surface is “even”…untextured…then as you spin, even though the finish still appears wet (and it is), the texture of the knurl re-emerges as the finish shrinks to follow the surface contours of the component. Don’t worry about the slight white/gray haze visible within the finish. If the finish was applied thinly enough (thick enough for full coverage, and no thicker), then the haze will disappear as the finish cures. Set the part in a warm place, safe from falling dust bunnies and their spawn. In 15 minutes or so the part is dry to the touch, but don’t be tempted…too easy to leave a fingernail impression or a faint fingerprint. Let the part cure for an hour or longer. If you want a more durable finish, apply another coat, bearing in mind that too much finish quickly looks thick and clunky. Less really is better, so long as the clear coat is sufficient for the purposes of protecting the oxide finish.
In closing I want to mention a few other processes worth exploring after you’ve mastered the cold oxidized finishes of BB & CC. My purpose in appending these alternate methods to this ramble is simply so that you know that cold bluing is the tip of an iceberg, and that you could spend years’ worth of free time exploring finishing options.
Japanning. This is a process which was used historically to darken & protect nickel silver or brass parts on fishing tackle. Essentially it is the application of black lacquer, or a lacquer-like substance comprised of various pigments, oils, resins, driers, and solvents, which is applied by dipping or brushing, air dried to allow the solvents to evaporate, then heat cured to achieve a hard, durable surface. This was one pre-cursor process to various baked enamel and epoxy finishes, and it’s worth exploring if you do a lot of restoration work.
Plating. Actually, electroplating. This is the process by which a charged component has metal ions deposited on its surface. Plating deposits are incredibly thin, which means that your base surface must be well finished and blemish free in order for the plated surface to be visually appealing. There’s not a sufficient deposition of material, as there would be with electroforming, to alter the surface texture, so the polish you achieve prior to plating is the level of polish apparent after plating. Elements of the plating process, particularly electro-cleaning and preparatory acid baths, along with rigorous rinsing, are definitely worth exploring as ways to “step up” your cold bluing regimen. Within rodmaking, black nickel plate over nickel silver is a common modern alternative to traditional oxide finishing. In our shop, we have both bath plating and pen plating equipment, the latter of which is useful for adding 24k gold detailing to parts prior to bluing.
Nano-ceramic coating. This is another electro-coating process, with elements similar to both plating and Japanning. Using this method, a charged component is immersed in a bath of clear or pigmented ceramic/binder solution until the desired color is achieved. And, again, the surface prep occurs before the ceramic is applied because the protective finish layer is so thin that it will not mask flaws in the underlying metal. After the part is coated and rinsed, it is heat cured, like a Japanned finish, to establish a clear or colorful ceramic layer that is more durable than an oxide finish, and almost infinitely variable in terms of potential colors which can be achieved by mixing the various ceramic/binder solutions. Golden Witch will be offering nano-ceramic finished guides by late 2016. The transparent ceramic option can be used over oxide finishes, to create a protective boundary stronger and more permanent than a lacquer clear coat, and with no discernable “build” to the finish. This will be great for traditionally finished parts. The fellows who make fiberglass rods, utilizing a rainbow of blank colors, will appreciate the colored ceramic options. Initially we’ll be offering vivid orange, deep violet, electric blue, beetle-back green, fuchsia, jet black, and a few more colors.
That’s it for now.
This ramble is continued over on the Golden Witch website, here.