Liquid Gun Blue

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1Kenny

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The lable on the Birchwood Perma Blue says it will not blue stainless steel,aluminum or non-ferrous metals. Would anyone know why? I would like to use it on the engine I am doing.

Thanks,
Kenny
 
Kenny
Gun blue is formulated to react with iron. The only other things I've seen that it will react with are brass and bronze and it ain't pretty...LOL. Brownell and Birchwood Casey both offer blues and blacks for other metals that... you guessed it... don't blue steel...(grin) Their web sites are chocked full of such things, including Aluminum Balck which is on my "to buy" list.

Steve
 
Thanks Steve,

For some reason I just knew I wasn't spending enough money to do this project. LOL

I will take a trip down the the local gun shop and see what he has.

Kenny
 
How scratch resistant are these finishes?
I have never used them, but if they are fairly hard wearing I just might try a few.
Also how easy are they to apply?


John
 
John,

A rubbing bearing surface would wear it off and it will scratch if ruff handled. But all in all, with care I think it would hold up like it does on a gun. It looks like I need three more bottles to cover the range. Thought I only needed two bottles ( one for aluminum and one for brass) till I saw the plum brown. That brown should work good for making bolt heads, shafts and cast look old.

Here is their web site.

http://www.birchwoodcasey.com/sport/index.html

I tried the blue on a piece of aluminum this afternoon and it just puddles and does nothing. Worked good on a piece of polished steel. On a piece of zinc plated steel it gave it a ugly finish.

This is the first time I have used it and didn't know it is a clear liquid.

Kenny
 
Thanks for that Kenny.
We don't get firearms suppliers over here, but a lot of it is retailed by engineering suppliers, so I think I will try some, and see how I get on.
I am still looking for a cheap supplier for the chemicals to do electroless nickel plating. It looks like I will have to call in a few favours, and get it thru the back door.

John
 
Seems like the steel 'cold blues' seem to plate down a copper layer (copper sulfate?) first, then darken that. Anything un-plate-able (Al, stainless, etc) won't work (FWIW, copper sulfate root killer has an entertaining instant copper-plating effect on steel and iron, but it's too thin and soft a layer to be useful).

I've had varying luck with them. Some steel cold blues very nicely (12L14 for one), and some just doesn't ever want to blacken nicely, no matter how much cleaning and steel-woolling is involved. They don't seem to be near as tough as a proper hot-blue, but the chemicals involved are a lot easier to deal with as well.

I'm not sure but some of the nickel-plate systems I think use copper as a base as well. That doesn't usually matter unless some ammonia gets into the mix..
 
The term hot-blue was new to me Shred. Up-on looking it up I think the cold blue is the way for me as I have been well counciled about useing the stove for my projects that need heating.

This is something I found that may be of intrest.

http://www.answers.com/topic/bluing-steel

Kenny
 
John,

Another intreresting thing is if you look at the birchwoodcasey site under the MSDS sheets they say what is in the bottles and the % of each. Kind of like getting the cook book.

Kenny
 
the gun blue comes with a dauber swab on a steel wire handle if you store in the bottle you may end up with gun brown DAMHIK
Tin
 
I have been using the 2 oz bottles of cold gun blue sold for use in touching up firearms. Works OK.

As someone has already noted, these are more effective on some steels than on others and of course not on stainless at all (unless specifically for stainless).

These solutions are acidic in nature and you need to degrease your piece very well before starting.

What I do:

1) Degrease part - use your favourite method but get it clean.
2) pour the contents of the 2oz bottle into a plastic cup and place the item to be blued into the solution.
3) swish, swirl, stir or whatever until desired color is attained.
4) remove and wipe with clean rag
5) place freshly blued item into another plastic cup containing a week alkylii - I use something like spray 409 or simlar household cleaner and swish swirl or whatever for a bit. This step neutralizes the acid of the bluing solution. Simply wiping, washing and oiling isn't sufficient - several piecies I have blued without this step but only washed and oiled ended up showing rust in threaded areas and corners and edges. I haven't had this happen since I have started using the neutralizing step. **note: when you place your part in the alkylii solution you may get some bubbling which should only be momentary.
6) If I don't need or require the part immediately I will put it in a container with enough oil to cover the part until I need it, sometimes for an hour sometimes over night - this step is probably not needed if you give the part a good and thorough oiling. This is just my work flow - the last thing I do is blue the part, set it to soak, clean up and turn out the lights.
7) the bluing solution in the first plastic cup is then put back in its original bottle for use another day. Dabbing the solution on the part works as well but I found it quite wasteful for small parts as well as awkward for small parts. You will find the solution will last some time but you will get some precipitate in the bottle that is best filtered out the next time you pour it out of the bottle.

Gently warming the solution in warm water as well as you part will make the process more effective. But be aware that any kind of solution such as these that are warmed or heated will give of vapours that will be far more dangerous than if you had not heated the solution. Proceed cautiously!

Of course you mileage will vary.

You may find the information in this old book helpful:

see: http://www.archive.org/details/metalcoloringfin00kauprich

This is a PDF downloadable document and quite interesting. It is dated in the early 1900's. some of the common names of the chemicals have changed over the years but a google search will sort that out. Many of the chemicals specificed are quite dangerous when improperly handled and used so do be careful.

What the world needs is a simple, safe, cold, metal coloring process to add blueig or browning or whatever that will provide a tough, hard wearing, long lasting finish to metal parts. So far there isn't one that I know of.

cheers, Graham
 
I noticed in the latest copy of Moder Application News Magazine Birchwood Casey also sells "Tool Black" I see they also have a tool black gel.
Tin
 

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