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Old 11-18-2016, 08:21 PM   #31
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Originally Posted by Buchanan View Post
What oil do you use. I can get a good blue but when I oil it, the blue goes dull. I use engine oil.Thanks for the feedback.
I did do some steel blackening and used a gun treatment to provide additional protection. Probably BreakFree or something similar. Got the materials form a sporting goods store if I remember correctly. This certainly isn't blueing in the Blue sense.

These people sell a kit: that seems to meet the needs of model engineers and the like. I suspect it is similar to what I used on a spacer block made for a tool post. It has held up well so far. Interestingly Caswell calls the coating a sealant. I have some other stuff I need to treat so Caswell may be getting an order from me soon. In any event don't have much experience beyond a couple of pieces and there I can't remember where I got the materials. I believe they where Birchwood-Casey.

Side note to myself, I really need to start writing this stuff down, old age is not kind to memory.

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Old 12-18-2016, 05:22 PM   #32
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I have been using a chemical blueing agent from :Brownells:
They have provided blueing solutions to metal workers for many years.
Rather than deal with heated solutions I use their cold blues labeled "Oxpho-Blue" and "Dicropan T-4", they are both very wear resistant and attractive as well as being simple to use.
Results through out the years have always been great and well accepted by fussy folks.

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Old 12-24-2016, 12:53 AM   #33
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Hot blueing chemically changes the surface layer of the steel to the same composition as haematite, it's harder than the steel and is porous allowing it to absorb and hold oil.
Cold processes do not produce a coating of the same composition or wear resistance.
W.C. Fields said "You can't cheat an honest man", he should have followed that with "But, you can always find a credulous fool if you need one"
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Old 12-25-2016, 12:33 AM   #34
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Originally Posted by Nick Hulme View Post
Hot blueing chemically changes the surface layer of the steel to the same composition as haematite, it's harder than the steel and is porous allowing it to absorb and hold oil.

Cold processes do not produce a coating of the same composition or wear resistance.

Which brings up some interesting questions:

1. Does anybody know of a good web site that covers hot bluing processes from the hobbyist level?

2. Same question for color case hardening especially as an alternative to bluing.

3. Has any one tried the Cerakote type ceramic finishes for use on shop tools? I see potential here as an alternative to bluing but have no experience with respect to durability when handled in this environment.

I ask because i have some tooling bits and pieces id like to blue and was going to go with a kit from Caswell. In the back of my mind though there is this concern that the cold processes aren't as durable as the processes they replace.

In a nut shell looking for a durable but not too complicated way to finish steel parts. Especially parts that will be handled a lot.
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Old 01-09-2017, 09:47 PM   #35
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Are you trying to blue tooling? if so cold bluing is a good option.

Sure, it isn`t very durable but its good enough for tooling and seems to be what manufacturers use in most parts. Plus, if you keep your tools oiled they shouldn`t rust. Parts that are handled a lot will always develop some patina from handling, but the patina is a good thing as it will keep the part from rusting badly(kind of like rust bluing)

Rust bluing is an alternative...but it takes a LOT of work, which in my opinion is uncalled for in tooling.

hot bluing consists basically of using molten lye (sodium hydroxide) to dip the part in. that bath runs at around 300 degrees celsius.(which could ruin the hardening of parts)
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Old 01-17-2017, 03:52 AM   #36
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I might be wrong but the blue that Chris (Clickspring) get on his parts is just surface and very easily removed. Just too much handling will start to thinnen the blue surface. One of his vidoes show it well, the video of the click spring. If you watch the click, you will see the surface that rubs on the gear looses its blue quickly.
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Old 01-17-2017, 09:09 AM   #37
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I must say that it's passed almost 8 months since I blued my part, and she is a boring head.
I don't use her too much, but in this 8 months I've used it quite a bit.

The only places where I'm having some problems are in areas where she was not completely clean before the hot bath in brass, and started to develop some rust.
All the other blued part are still there holding their wonderful blue, and so far I don't see any important scratch.

A boring head is somewhat prone to get scratches for all the chips that reach her during the job. So I'm satisfied.

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Old 02-16-2017, 08:19 PM   #38
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Hi Pigi,
Very helpful ,it will be useful on future projects.Thanks for sharing.
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Old 02-17-2017, 08:45 PM   #39
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Having a degree in gunsmithing, I have used a lot of products for blueing, but the one I keep coming back to for ease of use and durability is Mark Lee Express Blue, available at Brownells.
It is applied with a heat source until chocolate brown and activated by a five minute boiling water bath. Then carded with steel wool or a carding wheel, then waxed while hot. That's it.
It can be a lot of work on gun parts since there is usually so many, but for an odd part here and there, its hard to beat, and I've pretty well quit using hot caustic salts. It comes out a satin black, has good handling resistance, and won't hurt heat treating.
So if you aren't looking for an actual blue color, or a glossy shine, its good stuff.

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