Alternatives to Gun Blue

[IRstuff]

Are there alternatives to Gun Blue that are more corrosion resistant, or is that the nature of steel passivation?

I've got some fairly hard carbon steel that is exposed to water and ice, and I've just recently hit upon the idea of using gun blue to passivate and protect the steel, but it looks like it's not quite as robust as aluminum anodization, so I'm looking for alternatives.

Thanks



TTFN

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[BJC]

Guns are blued by immersion in hot ( 400 F) salts baths.
The finish is pretty if the prefinish is good.
Even a gun with a blued finish takes maintenace and oiling.
"Rust never sleeps"

IF your dealing with water and ice Galvanizing is the way to go.

 

[Eltron]

How big is this thing? Can you powder coat it?

Dan

http://www.eltronresearch.com

Dan's Blog

 

[KENAT]

IRstuff, are there some kind of limitations that prevent you from using a more typical protective coating & 'paint' system or the like?

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[IRstuff]

Yeah, it's part of an assembly that also has polymers, etc., so whatever I use has to be applied on, like the "Super Blue" that I'm using right now.

It's just that aluminum anodize is way more robust than blueing, since aluminum anodize can even be run in salt fog and temp/humidity testing without any other prep.

TTFN

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[Pud]

We have a customer who used to have parts machined from steel, harden them and then Zn + passivate.

I suggested Nitrotec - single process with added benefits. He is really impressed with the results (and it's much cheaper!)

I see there is a licencee in the US:

http://www.fpmht.com/capabilities/nitrotec_furnace/

Good luck.

Cheers

H

http://www.tynevalleyplastics.co.uk

 

[MikeHalloran]

Anodizing is never really used by itself; it always includes a seal coat of a clear finish, often with dye included. That finish is IMHO responsible for most of the corrosion resistance.

Something similar should work as well on blued steel.



Mike Halloran
Pembroke Pines, FL, USA

 

[IRstuff]

Lots of great ideas, but this is for edging on a ski, so most of them are not feasible for this application. This reason this came up is that my skis were squirreled away in the garage for about 8 yrs, and I just managed to sand and grind off the accumulated rust and applied some blueing, but all the documentation states that you still need to oil the surface...

TTFN

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[ivymike]

8 years without using the skis? that's why I don't own 'em anymore. If you were to start your own ski company, you could go with stainless edges or perhaps Ti. Ti seems to work for dive knives.

 

[patprimmer]

Spray on mould protection wax before storage.

Dip in electro-less nickel coating solution.

Ski more often.

The last is by far the best option.

Regards
Pat
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[IRstuff]

I have no arguments or justification...

TTFN

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[MintJulep]

Back in the days of cadmium plating on everything millitary if it was necessary to touch up an area where the cadmium plating was damaged or compromised due to rework the standard touch-up was "brush Iridite".

It's been a long time, but I think this was the stuff that we used.

http://galladechem.com/specs/macdermid/78650.pdf

Reading the TDS now, I doesn't look appropriate for application to bare steel, but that's what we did.

 

[btrueblood]

Always put them away with an end-of-season hot wax.

A friend that worked in machine shops used to put a long strip of Cor-Tech anti-corrosion paper between the skis before storing them for the summer.

 

[catserveng]

Might try your local gunsmith, a few I know of,

KG Gun Kote, used by the Navy Seals, very durable

DuraCoat
Metalife
Robar NP3
BearCoat

There are a number of finishes from hard chrome to teflon used on firearms, many with excellent results. There are some that can be self applied, just not as good as the shop finishes.

Mike L

 

[KENAT]

Maybe just accept that it's something you'll have to routinely repair/do maintenance of?

What was it's treatment originally?

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[IRstuff]

Pehaps...

The original is bare carbon steel, I think. Not sure how durable any of the paint-like coatings might be, and if the edges need to be tuned (sharpened) the coatings would have to be reapplied. Looks like gun blue might still be the overall winner here, since it's relatively trivial to apply after tuning.

Kenat,
Seems like some of the coatings recommended might be apropos for your microscope clamp. Most of the recommended coatings appear to epoxy-based.

TTFN

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[KENAT]

Might just be.

Although, I may have to rethink my microscope clamp for other reasons.

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[evelrod]

Well, my hobby is gunsmithing. I build and repair my blackpowder muzzle loaders. I have several caplock revolvers that are blued, but on my Sharron barreled flintlock Hawkin I used the ancient method of preserving steel of "browning". Simply let the thing rust real good and then oil it up. It's been that way now for 30 years and I have one that was done possibly 200 years ago.

Hey, it looks really good on a vintage gun...I'm not so sure it's workable for anything else.

Rod

 

[BJC]

"Looks like gun blue might still be the overall winner here, since it's relatively trivial to apply after tuning."

You are talking about "Cold blue" I assume.
Serious gun bluing is hot bluing is done in a tank of salts in water solution. The bath is 400 degrees F.

Double barrel shotguns are never hot blued because the temperature of the bath is hot enough to melt the solder.

 

[evelrod]

BJC, I'm pretty sure "hot blued" doubles exist...pretty sure 'cause I have a 20g Rossi coach double that is so finished.

Rod