Need help with finishes on C96

[alvin]

I tried 7.62mm Tokarev Snap Caps, they could not even stands well on the clip -- shaking the clip, a few snap caps will fall off from the clip. The fitting is very poor. By visual, I cannot tell snap caps dimensional difference either.

I bet Serbian made PPU 7.63mm were modified from their 7.62mm Tokarev. Historically, Yugoslav had tons of Tokarevs, not many Mausers. It would make sense for them to create 7.63 Mauser from 7.62 Tokarev for US C&R market.

[alvin]

Originally Posted by Olle

I had the camera and the photo tent set up today, so I decided to take some better pictures. I'm not entirely happy with the grips, but haven't been able to find any better. I might stain them a bit later to make them look old, but they will do as they are for now.

I have always wanted a nice C96 shooter, so I'm pretty happy with how it turned out overall. Also got a Bolo that needs some attention, so I guess that will be the next project. Might even convert that one to 9mm.

Olle -- You did better than Eugene. I saw Eugene's work on internet, frankly, his work is not at this level yet. If you open a business on this, I guess there will be demand.

Suggest erasing the blue on lock frame using Casey Rust & Blue Remover. Original gun's lock frame is not blued. Not silver bright either. It should be hardened steel light grey color.

There are some other places.. but I will keep those secret

[ithacaartist]

Originally Posted by John Sabato

Alvin keep your eye on Harbor Freight sales. They often offer digital calipers that are plenty close enough in accuracy for reloading work.

http://www.harborfreight.com/6-in-di...ngs-68304.html

John, this is the same calipers that I bought from Harbor Freight a couple of years ago. There is an offset of the claws that do inside measurement, when the O.D. jaws are zero. But I compensate by locking the travel down on an I.D. and measuring the claws' spacing with a micrometer. Mine also gradually began to lose its consistency, as in when drawing the jaws apart, an extra 1/4" or so adds itself to the displayed dimension. I am inexperienced with the electronic calipers and suspect a weakening battery?

[Olle]

Originally Posted by alvin

Olle -- You did much better than Eugene. I saw Eugene's work on internet, his work is not at this level yet.

Suggest erase the blue on lock frame using Casey Rust & Blue Remover. Original gun's lock frame is not blued. Not silver bright either. It should be hardened grey color.

There are some other places.. but I will keep those secret

I don't know if I'm better than Eugene, but at least I'm quicker...

I know about the lock block, I just thought it would look better like this. This one will hopefully be used, and the bluing will hold up better than bare metal. I would like to protect the hammer too, might try a dull nickel on the next one.

Feel free to point out whatever you find, this will help me do better next time

[alvin]

For nitre blue, what's the temperature used, and how long you soaked the parts into the melted salt? How do you control the temperature at a constant?

Curious, because I saw many restored guns have darker nitre blue finish than original guns. I guess the color tone being temperature and time related... but not sure.

[Olle]

Originally Posted by alvin

For nitre blue, what's the temperature used, and how long you soaked the parts into the melted salt? How do you control the temperature at a constant?

Curious, because I saw many restored guns have darker nitre blue finish than original guns. I guess the color tone being temperature and time related... but not sure.

I used a torch for some of them, but sent off the difficult ones to Paladinpainter. The color does depend on the temperature and can be adjusted as necessary. I don't believe the time matters, as long as the temperature is correct. Of course, the time will matter if the temperature is too high, simply because of the heat sink effect. This would also give you different colors on the same part, depending on how quickly thinner and thicker sections got up to temperature.

You need to keep in mind that it's a very fragile finish, and the best way to get an idea of the original color is to take a part off the gun and inspect areas that haven't been exposed to wear. I believe the colors on this one are actually close to original, just darker because there's no age on it.

[Olle]

Originally Posted by ithacaartist

John, this is the same calipers that I bought from Harbor Freight a couple of years ago. There is an offset of the claws that do inside measurement, when the O.D. jaws are zero. But I compensate by locking the travel down on an I.D. and measuring the claws' spacing with a micrometer. Mine also gradually began to lose its consistency, as in when drawing the jaws apart, an extra 1/4" or so adds itself to the displayed dimension. I am inexperienced with the electronic calipers and suspect a weakening battery?

Weak batteries can play tricks on you. The digital readouts on my mill will start changing to metric by themselves when they get low, and you can see that the display is a bit dim as well. It's just their way of telling you that they want a new battery.

I have used Mitutoyo's "solar" calipers ( http://www.amazon.com/Mitutoyo-500-4.../dp/B001C0ZPUW ) for years, and I'm very happy with them. They are a bit more expensive than battery powered calipers, but you never have to worry about running out of battery again. They are high quality and will last for a long time, so the higher cost will more than likely be offset by the money you save on batteries.

[DonVoigt]

Originally Posted by ithacaartist

John, this is the same calipers that I bought from Harbor Freight a couple of years ago. There is an offset of the claws that do inside measurement, when the O.D. jaws are zero. But I compensate by locking the travel down on an I.D. and measuring the claws' spacing with a micrometer. Mine also gradually began to lose its consistency, as in when drawing the jaws apart, an extra 1/4" or so adds itself to the displayed dimension. I am inexperienced with the electronic calipers and suspect a weakening battery?

If you have not changed the batteries several times in two years,
it is the battery. I don't get more than a few months out of a battery!

But it would depend on how often you leave it on.

[Olle]

Originally Posted by alvin

I guess the color tone being temperature and time related... but not sure.

Found a web site that explains this quite well: http://tincanbandit.blogspot.com/201...at-bluing.html . One of the pictures shows the colors you get at different temperatures, and here you can see that nitre bluing and strawing is the same type of process, just different temperatures.

[ithacaartist]

Originally Posted by DonVoigt

If you have not changed the batteries several times in two years,
it is the battery. I don't get more than a few months out of a battery!

But it would depend on how often you leave it on.

Don, I use it rather infrequently so far, but time does slip away, as you know. It came with a spare, but it is pooped out, too. My list for tomorrow already has the button cells on it! Thanks for confirming my suspicions. I was a little afraid I'd wasted my $14.95 or whatever!

Originally Posted by Olle

Found a web site that explains this quite well: http://tincanbandit.blogspot.com/201...at-bluing.html . One of the pictures shows the colors you get at different temperatures, and here you can see that nitre bluing and strawing is the same type of process, just different temperatures.

Olle and Alvin, the great news is that all these colors can be accomplished in your toaster oven! The difficult part is setting the dial for the correct temp to get the desired color, but once established , after a bit of experimentation, mark the dial and you can reproduce any time. A pan of clean sand that's deep enough to immerse the part is left in for a good long time to stabilize its temp. After pre-heating the sand, snuggle the polished, degreased part down in and leave in the oven for a good long time so the part is thoroughly heated through to that temp.

[alvin]

I bought a worn C96 extractor which lost its finish. Planned to use it on a range gun.

Also bought a bucket of nitre blue salt and a temperature meter. If my spouse allows me to borrow her cooking stove, I will have some fun in Christmas. She told me that she will think about that and let me know.

Surely, I will experiment on scrap steel first.

But there is a strength problem -- does this 570F - 670F temperature anneal the steel?

[alanint]

Alvin,

The best thing to do is come up with a reason for your wife to leave the house for 6-8 hours and have everything cleaned up and aired out by the time she returns.

This will usually insure a second opportunity to blue.

[DonVoigt]

Originally Posted by alvin

I bought a worn C96 extractor which lost its finish. Planned to use it on a range gun.

Also bought a bucket of nitre blue salt and a temperature meter. If my spouse allows me to borrow her cooking stove, I will have some fun in Christmas. She told me that she will think about that and let me know.

Surely, I will experiment on scrap steel first.

But there is a strength problem -- does this 570F - 670F temperature anneal the steel?

Alvin,
can you explain exactly what you bought as "nitre" blue salt and how it is to be used?

I have a lot of experience with hot salt bluing and it is not something you will want to do in the kitchen.

Yes, anytime you heat metal it "anneals" it, but the temperature you will reach in hot salt bluing will not significantly affect the "strength".

Annealing will remove any stresses built up from machining, forging and forming steel. Your part has already likely experienced those temperatures.

[Olle]

The color you see on the on original parts is not meant as a finish, it's actually a byproduct of the tempering process they used at the factory. The good thing about it is that the color is a great temperature indicator, so if you heat it to the factory color you won't exceed the temperature the factory used to temper it. You can do any part like that without hurting it, and some say you might even prolong the life of parts that have become "work hardened" by years of use. However, if you heat it too much, you have to reharden and temper again.

Annealing is a totally different animal. This is done to soften the steel before you work on it, and you have to heat it to a much higher temperature (glowing hot). The only color you get is steel grey.

[Olle]

Originally Posted by ithacaartist

Olle and Alvin, the great news is that all these colors can be accomplished in your toaster oven! The difficult part is setting the dial for the correct temp to get the desired color, but once established , after a bit of experimentation, mark the dial and you can reproduce any time. A pan of clean sand that's deep enough to immerse the part is left in for a good long time to stabilize its temp. After pre-heating the sand, snuggle the polished, degreased part down in and leave in the oven for a good long time so the part is thoroughly heated through to that temp.

I do it in the oven now and then (when wifey is away...), but I just put the parts on a piece of aluminum foil. Sometimes I suspend them from makeshift wire hangers. This allows me to see the parts and abort when they have the right color.

IMO, the most difficult part of it is to get a nice, even polish, and to get the parts clean enough to take on an even color. Do you get a uniform color when you use sand, or can you see small marks where the sand has been touching the steel?

[alvin]

Originally Posted by DonVoigt

Alvin,
can you explain exactly what you bought as "nitre" blue salt and how it is to be used?

I have never done things like this before. From youtube.com video, midwayusa showed how -- the nitre blue salt is a pink color solid stuff, he put the salt into a pan and "cook" it. The salt melted. Then, he dipped small parts into the melted salt, the metal color changed, then he took it out. That's it.

He did not explain the theory. Here is my guess -- that salt melts around 600F. So it's just temperature control media. This is obviously more controllable than using a torch to create fire blue on small parts -- using torch, you have no control on temperature, using this type of salt, it's much easier to control, and the metal is heated much more uniformly. Unlike regular bluing process, I don't think there is a chemical reaction between the nitre salt and metal. Just a guess.

Here is the video:

https://www.youtube.com/watch?v=-vF3zKiUIkY

[Olle]

Originally Posted by alvin

I have never done things like this before. From youtube.com video, midwayusa showed how -- the nitre blue salt is a pink color solid stuff, he put the salt into a pan and "cook" it. The salt melted. Then, he dipped small parts into the melted salt, the metal color changed, then he took it out. That's it.

He did not explain the theory. Here is my guess -- that salt melts around 600F. So it's just temperature control media. This is obviously more controllable than using a torch to create fire blue on small parts -- using torch, you have no control on temperature, using this type of salt, it's much easier to control, and the metal is heated much more uniformly. Unlike regular bluing process, I don't think there is a chemical reaction between the nitre salt and metal. Just a guess.

Here is the video:

https://www.youtube.com/watch?v=-vF3zKiUIkY

That's correct. The nitre salt is just a media that allows you to apply the heat in a controlled manner, otherwise it's the same process and the same finish as you'd get with a torch or in the oven.

One reason why I don't use nitre salt (and bluing salt) is that I don't like the idea of working with salt heated to high temperatures. I figure it can make for some interesting steam explosions if there's rinse water left on the parts. Still, many videos show the guy dipping in the nitre bath, dipping in a cup of water, then back to the salt again etc. I might be overly cautious, but I figure the torch and the oven are much safer.

I do extractors on a thin piece of shim stock, I heat with a torch from underneath and when I have the right color I drop it in quenching oil to cool off. The color doesn't appear immediately and it can continue to develop after you quit torching the part, but the quenching will stop the process right at the moment it's submerged and keep it at the right color.

[DonVoigt]

Originally Posted by alvin

I have never done things like this before. From youtube.com video, midwayusa showed how -- the nitre blue salt is a pink color solid stuff, he put the salt into a pan and "cook" it. The salt melted. Then, he dipped small parts into the melted salt, the metal color changed, then he took it out. That's it.

He did not explain the theory. Here is my guess -- that salt melts around 600F. So it's just temperature control media. This is obviously more controllable than using a torch to create fire blue on small parts -- using torch, you have no control on temperature, using this type of salt, it's much easier to control, and the metal is heated much more uniformly. Unlike regular bluing process, I don't think there is a chemical reaction between the nitre salt and metal. Just a guess.

Here is the video:

https://www.youtube.com/watch?v=-vF3zKiUIkY

Alvin
What you describe is Not typical hot salt bluing. Which is a chemical reaction, not just heat. Salts consist of sodium hydroxide and sodium nitrate, and each contains some crystalized water.

Tempreature is controlled by adding back water as it boils off, or the temprature will increase as time goes by.

It is a hazardous and corrosive mixture, rubber gloves, rubber apron, face mask, etc are recommended as the salts will splash.

You will corrode your stove and vent if you do it much!

Salt bluing is best left to an expert with the proper set up and know how.

It is not a do it in the kitchen operation.

Metal preparation is the most important step, followed by degreasing before putting into the salt.

Poor prep = poor results.

What is shown in the video is the same as what the others are describing using the oven or hot sand in the oven, he is using a salt bath to
control the temperature to 600 degrees+/- to achieve the pretty blue. It is heat treating as Ollie has described.

[alvin]

No. Not salt blue.

Above video is nitre blue (a.k.a fire blue), which is applied on extractor, trigger, etc.. small parts finish.

[ithacaartist]

Here's the deal on the toaster oven and the sand. The oven is capable of reaching the temperature needed to make a piece of steel turn dark blue/black--in the 500's somewhere. Straw is 300-something IIRC. The toaster oven heats by direct radiation (that's what toasting is all about.), and maintains temperature within a range, via its adjustable thermostat. The element comes on and shines heat inside the box, and shuts off when the thermostat detects its limit. When it is heated, a part which has thick and thin areas (safety lever, takedown bolt) will have overheated thin portions if the thick portions are heated enough to achieve the right color, if the heat in the oven is above the prescribed temp for the target color. The box of sand at stable temp ensures the entire part reaches the exact temp--and no more! This ensures even color. The setting numbers on the oven's dial are used only to be a relative reference, and need not be strictly accurate.