Does anyone know anything about hard chrome plating? Henry has an all weather 45/70 lever action that they used hard chrome plating. Henry claims it wont flake,chip or peel and that its corrosion resistance is even stronger then some stainless steels.

Yes , I do ! Yes they are right --providing that the hard chrome is done properly !!! I've never handled a Henry of any kind. I'll look at their website . Anything to help a fellow Catskill Mtn guy !

I had my Ruger 77 MKII done over 20 years ago and have hunted Alaska and New Mexco ever since with it and the finish looks exactly like it did when it was first done. Tough stuff.

Don't confuse the plating put on by gun makers, to the chrome plating on your 57 Chevy bumpers; different process and it won't flake off.

Car chrome is 'soft chrome ' very different from
hard chrome .I hear from mechanics that with soft chrome they are taking lots of short cuts. !!
Hard chrome , you still have to do it properly !

first time for me Mete, last year we got a new hunter among us he was using a henry big boy in 44 mag. that was the first time i ever handled a henry,his was the brass model with octagon barrel. nice looking rifle but not for me for hunting , to heavy, but the new all weather 45/70 has caught my eye and besides i do need another 45/70. thanks for the replies.

Hard Chrome originated as an industrial process. Firearms manufacturers came along later.

http://www.electrohio.com/Fini...hrome/HardChrome.htm

A North Carolina friend had an Anschutz 54 receiver done in what he described as "industrial hard chrome". Mated with a dull polished stainless barrel it really looked nice. From what I understand the plating thickness is in the 0.0007-0.0008 inch range, providing limited impact on tolerances. I'm not personally sure about those dimensions, perhaps someone who is "in the know" will share specifics.

Edit: the link in the post above this one gives plating thicknesses.

The guy I apprenticed with used to hard chrome bolt bodies on misurp rifles after he forged and finished them. I might even have an old 270 he did somewhere in the safe. His reasoning was that the bolts seemed to take the most abuse sitting in somebody's garage in Florida unused for 10 years. I liked it on my few that he did because the bolt is the metal you handle most and the most prone to blue wear over the years, especially if your a sweaty fat guy like me. I think your thickness might be a tad thin, I remember turning bolt bodies, or at least polishing them and truing up raceways so the bolts would fit after chroming. They were always a bit stiff until we honed the actions half a frog hair or so.

I have questions:

1. Could one just chrome an entire Mauser bolt, minus the shroud and firing pin?

2. If so, what company is known and well respected for this kind work?

IIRC a chromed bore starts out larger than standard to compensate for the chrome layer.

Electroplating presents a problem.Chrome plates faster [ thus a thicker layer ] with higher current desnity .This happens on outside corners. Holes also present problems and depending on dimensions you may have little or no plating in a hole
That's why I say go to a shop that has experience in gun work.

Hard chroming (grey chrome not shiney) is great for wear resistance & building up worn/undersize components.

its corrosion resistance is highly dependant on the substrate metal.
electroplated industrial chrome is porous at the molecular level & does not provide galvanic protection ..... hence why other metals are laid down below hard chrome where good corrosion resistance is required.

This is the same issue as between electroplated zinc & hot-dipped zinc for corrosion protection.
electroplated zinc needs to be 'reflowed'( ie heated to melt & provide a seamless coating at the molecular level ) to provide the same corrosion protection as hot dipped galvanising / zincplating .

The corrosion protection is achieved as a barrier of corrosion resistant / slow oxidising metal, just like the coating on tin cans.
NB
continuous electroplated steel strip is reflowed utilising an induced eddy current to melt the surface coating before recoiling & further processing into tin cans............otherwise tin cans would corrode from most of their contents, many food cans are also lacquered on the inside to ensure the surface is sealed.

That said ........ typical oil finish on hard chroming works a treat.

Hard chrome plating by itself will not protect the metal its plated on from salty environments
eg
- seawater
- SWEAT
etc

That's true now that I think about it. I believe he would use electroless nickle on the handle for spiffing and protecting. I remember the bolt bodies would all be dull and the handles shiny. I'll dig one out later if I can find it. I think I still have the first bolt that I forged and he finished in this fashion.

There's electrolytic and electroless nickelplate.
Electroless has some phosphorous so you can actually harden it to some degree.It also eliminatessome of the problems of electrolytic..The BHP was made at some time with that finish.You could tell by the grey color.

quote:

Originally posted by mete:
IIRC a chromed bore starts out larger than standard to compensate for the chrome layer.

Electroplating presents a problem.Chrome plates faster [ thus a thicker layer ] with higher current desnity .This happens on outside corners. Holes also present problems and depending on dimensions you may have little or no plating in a hole
That's why I say go to a shop that has experience in gun work.

All pretty much spot on.

I have been working for the Govt as an Electroplater for 9 years. I work strictly on Helicopter parts at the largest military helicopter repair/retrofit/rebuild facility in the world.

In order to plate in a hole you need to mount an anode in the hole the entire length of the bore to be plated. There must be sufficient room for the evacuation of gas produced and for the solution (chromic acid with a touch of sulfuric acid) to pass through.

Conforming anodes have greatly reduced the time it takes to plate and improved the consistency of the thickness.

Whatever imperfections are present on the surface of the base metal prior to plating will be greatly magnified after plating.

I have always been intrigued with "chrome-lined bores". How thick is the chrome? I guess I need to find an old barrel and go at it with a chop saw. I would be surprised if there is more than .005" of chrome.

Car bumpers are a process known as Flash Chrome or Decorative Chrome. It is a TINY layer, around a couple of ten-thousandths of an inch.

Andy B

Electroless nickel is best for this; ;I get mine done at Craftguard Metal Refinishing. I have double rifle frames, etc, done by them. Chrome plating is too much drama.

There is nothing wrong with hard chrome. It can be even polished. These are hardchromed parts for my pistol: