"Chrome Plated" vs. "Hard Chrome" Finish?

D

DougB

New member
I am considering a relatively inexpensive (though decent quality), 15-20 year old handgun. I believe it is chrome plated (it is advertised as being stainless, but I don't think this gun was ever made in stainless, so it must be the chrome plated version). Anyway, I used to believe that this wasn't a very good finish (would peel off like the chrome on car trim, etc.), but now I see that "hard chrome" finishes are reputed to be very durable. Are these two different animals? Would the finish on an inexpensive old chrome plated pistol be likely to hold up well?

I could also buy a blued version for less $ and have it hard chromed or nickled. This probably wouldn't cost much more than the price difference between the blued and chromed versions of this pistol.

Thanks.

Doug
 
Doug, the finish you mention is not the hardchrome that is used by many of today's manufacturers and custom gunsmiths. The old chrome plated finish, if I'm not mistaken, was similar to that used on automobile trim and would usually flake off over a period of time. In contrast, the hardchrome used today was a by-product of the aerospace industry where superhard coatings were needed for satellites, space shuttle, etc.

A firearm is first prepped by stripping the old finish then polishing or bead blasting. It is then electroplated with a nickel undercoat with the hardchrome being applied over the nickel basecoat. Durability of hardchrome depends, largely, on the porosity of the handguns's metal and whether the initial polish job was performed correctly. If both were done well, the hardchrome will give you many years of excellent service, even in a saltwater environment. Of course, you must use common sense and keep the exposed chrome surfaces clean, just as you would any firearm.

Hope this helps.

SG

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The people's good is the highest law -- Cicero
 
This may or not truly apply since I imagine the term "hard chrome" is used as much as an attention getter as a technical term, but this does clarify the difference between the two:

"Decorative Chrome Plating can be likened to a "clear coat" on a paint job. It is a very thin layer of a bluish hue metal which is applied over a nickel plate. The nickel plate being the "paint job". Chromium has very poor corrosion resistance as, if applied on its own, it is very porous. It has a cracked porous appearance when examined under a microscope. Nickel, on the other hand, is very corrosion resistant, but it tends to slowly lose its shine unless polished occasionally. By applying chrome over nickel we obtain the best of both worlds, high corrosion resistance and longevity of shine. To distinguish nickel from chrome you should look for the yellowish/gold hue of nickel and the bluish tint of chrome.

Decorative chromium is applied in an extremely thin layer over nickel approximately 1/100th the thickness of a hair, or 0.000001".

Hard Chrome plating is applied to certain surfaces requiring a very tough wear resistant coating, such as hydraulic cylinders on earth moving equipment, where dust and debris can scratch untreated steel rams, causing the seals to leak.

Worn shafts of all sizes can be rebuilt successfully using this technique. It is possible to build up from 0.09" to 1/8" by hard chroming then regrinding to the correct diameter. Because the chrome is so hard, it cannot be turned to size but must be finished on a lathe equipped with a tool post grinder or on a centerless grinding machine.

When used as a bearing surface, chrome must be micro finished and will then provide a coefficient of friction lower than any other metal when used against steel, iron, brass, bronze, babbit, or aluminum alloys. Do not use chrome against chrome. Because Chrome is much harder than case hardened steel, you now have the perfect set-up for long wearing work surfaces.

Most metals can be hard chromed, e.g.: steel, stainless, bronze, brass."

This is from a manual I have on plating (before I got into shooting, I was a car nut and looked into rechroming my own parts, never got very far...). Based on this, I would guess that, for firearm applications, there are only variations on the decorative chrome plate, some just "harder" than others. I would have to second SG12 and say that I'm sure modern chrome plating on guns is probably better than that used in the past, but it's all still very similar to that used on auto trim. The difference would most likely be the conditions under which the plate was applied and simply how much care is taken in the process, as well as the base metal being plated (most of the auto trim that really didn't hold up was made of potmetal). I think a good chrome plate would hold up for a very long time if it was applied with great care and cared for properly. But, it's obvious that the automakers realized they didn't have time to do chrome properly anymore (how much chrome do you see on a new car?). Guns, on the other hand, can be given more time and care than your average stamped out car bumper. They are a small piece that is typically handled by a PERSON, as opposed to a machine when being produced. They are also a more convenient size to be "baked" to avoid problems with hydrogen embrittlement caused by chromic acid. Plus they aren't typically exposed to the elements the way that auto trim is.
The big question would probably be just what type of base metal the gun in question is made of. We know that potmetal doesn't hold up, but good steel/iron will last for many years under a well-done and well-cared-for chrome plate.
Basically, I've just seconded SG12's post as far as the need for initial care in the application of the plate and the importance of a good quality base metal, but I hope I have shed more light on things :)

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"...That is why, I pack my .25. Where nobody knows, right above my boot. It's the law, no one there to serve you. Why not be the hero? Why not be your own? Swear I'll kill you!.." Porno for Pyros - Packin' 25
 
hard chrome does not look chrome colored. it is much duller and not shinny at all. my beretta 92G Elite has a hard chrome finish on it. i like it a lot. it looks really cool and is very durable. i bought the gun used with the finish already on it so i'm not sure of the cost exactly. the whole gun and 2 magazines were chromed and i think it cost about $150. if you want to get a new finish on one of your guns i would highly recommend it.

i'd go with the cheaper blued finish and then hard chrome it or get some other finish like NP3 (although i hear some people don't like this as much).
 
I agree with Russell on the look of hard chrome. Hard chrome is not shiny. The slide of my P-32 is the hard chrome model. It looks kinda like brushed stainless steel. Looks good!

Will

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Mendacity is the system we live in.
 
Actually, hard chrome is as shiny or matte as the underlying steel. Apply it to mirror-polished steel and it'll look like a bright nickel job. Apply it to bead-blasted steel and it'll look matte. It's all in how the substrate is prepared.

Rosco
 
Hard Chrome vs. Decorative Chrome Plating

Yes, Hard Chrome Plating & Decorative Chrome Plating are 2 different animals.

The chrome itself is the same in each, but the process, thickness, and function of each type are completely different. Hard Chrome provides wear-resistance & lubricity while Decorative Chrome is aesthetic (i.e. “pretty”). I help operate a Hard Chrome facility, so I have answered this question many times.

HARD CHROME PLATING (often called "Industrial Hard Chrome", "Thin Dense Chrome", or simply "Chromium Plating") provides wear-resistance and lubricity on bearing surfaces, seal surfaces, and wear surfaces for parts like hydraulic cylinders, industrial rollers, machine pistons, and yes, gun parts. It is applied directly onto the substrate (“substrate” = the material/part that is being plated) via an aqueous electroplating process done in a tank full of water, chromic acid, and other chemicals to balance (watch out for the EPA in disposal of these chemicals; seriously). Hard Chrome is measured in thousandths of an inch (.001”) and tenths of an inch (.0001”). For reference, a sheet of paper is .003” thick. Typical thickness is .001-.005” thick/side for industrial parts, .0002-.0008” thick/side for a chrome “flash” (when there are complex surfaces being plated together that you cannot grind or polish), and .005-.030” thick/side for many military parts. A hardness test of Hard Chrome Plated surfaces often results in 65-70 Rockwell C (“RCH”). The RCH will be lower if you apply just a flash to a softer substrate. Also, carbon steel results in the strongest bond with Hard Chrome. Tool steel also responds well, but if it is extremely hard, adhesion may be an issue. Aluminum cannot be flashed since you must hit about .003”/side thickness before a solid bond results. So, you typically must finish-grind and/or polish after Hard Chrome plating aluminum. Copper, bronze, brass are eroded by Chromic acid, so you have to plate the entirety of the surface very quickly or else you risk damaging, distorting, or otherwise ruining the part. It’s a tricky process and not many facilities can do it. If a gun part has a serial number on it, a facility cannot plate it unless it has a FFL (“Federal Firearms License”). If not, then any facility can do it. But be careful who you let handle your piece because muriatic acid is used to strip chrome, and multiple trial-and-errors with multiple strips could devastate the integrity of the parts. Typically, gun parts are plated .0001-.0004” thick/side so that they will fit back together, and this results in an EXCELLENT durable finish. Get someone who knows what they’re doing because there are some tricks to plating these parts that will make ALL the difference in the result.

DECORATIVE CHROME PLATING is used for automobile hub-caps, bumpers, pipes, show pcs, as well as sinks, motorcycle parts, various medical pcs (like I.V. hangars), etc. It is applied with a very thin under-flash of Copper and/or Nickel. The thickness of the Chrome itself is measured in millionths of an inch (.000001"). This results in a brilliant, shiny, silvery finish. It holds up relatively well in weather, but is not very wear-resistant over time (I'm sure you've seen cars with peeling/cracking/chipping plating). You cannot conduct a hardness test on Decorative Chrome Plating because it will crack like an egg shell due to it being very thin.
It is very rare to find both processes under one roof because they require different setups, serve very different markets, and a small mistake could easily result in mixing chemicals incorrectly, resulting in expensive contamination.
 
ANY plating shows the underlying surface finish-satin, shiny, whatever.
Hard chrome is not applied over nickel. It is applied directly to steel.
Decorative chrome plating, when properly done, is also a very durable finish.
Now, if the OP would provide a picture of this gun-or maybe even just the make/model, we could tell him what the finish actually is!
 
For those who think that hard chrome is new -- hard chrome has been around for at least 50 years !! I've used it for that long .:p
If you decide to hard chrome a gun make sure you send it to a reputable gun plater that has experience plating guns.
A chemically clean surface is required for a good bond to prevent peeling. That is done with hard chrome by first reversing the leads and 'deplating' that produces a matt finish which is seen when the plating is completed.
 
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Just trying to give an example of hard chrome^^^

The inside of the brake above is hard chromed to help with shooting corrosive ammo.
 
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