Oil Blackening my old enfield? Is it safe?

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CanadianBaconPancakes

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Well, its oil change time... Ill have 8 litters of nice used oil I would like the blacken my old enfield with. Dose anyone see anything damaging to the metal to heat, quench, heat, quench, and so on?

Thinking of using a propane and or map torch.. Also using synthetic oil ( mobile 1)

I think this would be a better alternative to paint and more durable then bluing, along with FREE :D


If all good, Any tips? This will be my first time.
 
Heating and quenching over and over sounds like it would be an absolutely terrible idea for the steel.

How hot were you planning on heating it?
 
I wouldn't, you will ruin the gun. This sort of colouring works well on knifes. But you would ruin the tempering if you get it too hot.
You will make the old "ordinance" steel very brittle and prone to cracking.
 
Go for it. The world need more tomato stakes! Not a LE fan! :) )

Right up there with reading chicken entrails, as far as scientific methods goes. Except the chicken entrails only hurt the chicken.

Which is to say, stupid idea.

Cheers
Trev
 
Jeeeeeezbuss H Murphy Cripes trevj...........................didjah git a Starbucks in Lillyland...........................:runaway:..................:cool:
 
It's not as stupid as some think and at one time was an accepted method of finishing. It does require a lot of heat though and it isn't nearly as durable as the OP believes. It is after all is said and done nothing more than a hard carbon surface and it isn't as durable as the later finishes.

I have carbon coated metal and it has to be at least 300F before any sort of lasting carbon finish is left behind. I wouldn't do it to a barrel or receiver but it is my understanding that it was done. Maybe on some black powder arms.

The metal I coated didn't need to be strong, just rust resistant. I did enhance the blackening with a very light coat of acetone and varnish. It lasted for a long time but was prone to wear from any sort of abrasion.
 
For any parts of the rifle that need to be correctly heat treated it's a really, really, really bad idea. As I read the online versions of how to do this I see that to get the part hot enough to cause the oil to carburize on the metal it ends up being up well over any normal tempering temperature. So the metal under that baked on black varnish like film will be totally annealed (IE; soft like cheeze).

Also you're looking at adding a varnish like film to the metal. And that could affect the fit of some parts when you put it together. Or if you try this without taking it apart it'll glue all the small parts in place.

When I've oil hardened small cutters and such they blacken up and look pretty good. But as bearhunter says it's a soft sort of finish and is easily removed. Making it thicker won't help that aspect.

Cold blue is actually a lot more durable than the carburized layer left from burnt oil.
 
I used to harden idler arms after they had been bent by some of the more nasty operations where I worked. We would heat them to soften them so we could straighten them. We had a special jig made up for our hydraulic press for this particular job. Once they were straight, they were heated to dull red then dipped in cold used crankcase oil. We had to be careful not to get them to hard. One fellow we had on the torches had a heck of a time distinguishing between bright red and dull red so someone had to be with him. These idler arms were already well carbonized or this process wouldn't have worked. It's a very old system and if the carbon is fortified with something can be reasonably durable.

I have done batches of stock ferrules/buttplates/sight protectors/bases and swivels in this manner. I don't do it any longer because I don't have access to the equipment needed to to the job properly. Small parts can be done for small projects but if you're planning on doing any quantity you have to figure out how much the fuel to heat those parts to get the coating you desire. The hotter the part, the thicker the carbon coating.

Also realize that some of that carbon will be absorbed by the original metal and may harden it to much. That's why I kept my temps to 300F. Just enough to turn metal a light reddish brown. This temp wasn't enough to temper the metal but enough to apply the carbon. The carbon also stays soft enough that it will absorb 25% varnish and 75% acetone. I like the acetone because it evaporates quickly leaving a nice finish that isn't bright and shiny but takes on the same texture as the carbon.
 
If the max you got to was 300f it could be fine. That temp wouldn't do much tempering, more of just a stress relief. Especially if not held at temperature for a long time.
 
Is this a troll post?

Don't.

Just don't.

You're going to spend more on gas to heat than it would cost to do a finish that won't hurt the gun. Barbecue paint is flat black, resists heat and solvents (if you bake it on), and costs $3 for a rattle can, or you could go big and spend $6 on some flat black header paint. That would at least look like suncorite at a glance, and has the added bonus of not removing your hands and face for you when firing.
 
ShawnC6 said:
If the max you got to was 300f it could be fine. That temp wouldn't do much tempering, more of just a stress relief. Especially if not held at temperature for a long time.
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Exactly, takes a lot of heat(in the thousand degrees where steel gets past red hot) to anneal or temper steel,what CanadianBaconPancakes is doing is what method used before chemical bluing was invented.In fact I believe but not 100% sure linseed oil was used and rubbed on with a rag on hot steel.
 
vstar650ca said:
Exactly, takes a lot of heat(in the thousand degrees where steel gets past red hot) to anneal or temper steel,what CanadianBaconPancakes is doing is what method used before chemical bluing was invented.In fact I believe but not 100% sure linseed oil was used and rubbed on with a rag on hot steel.
Click to expand...

Before there was chemical bluing, there was no smokeless powder.

At black powder pressures, nobody much cares how you treat it, or what it is actually made of, or, especially, what campfire you heat treat it over.

It does not take that much heat to anneal steel that has been hardened.
You can look up the heat treating temperatures yourself. ASME has some good info. Guys on forums, saying go for it, probably not so much.
Any temperature that produces a change in the oxide layer on the metal, is enough to change it's properties. You may get lucky, and the metal used to make that particular rifle was not badly affected, or you may end up with a grenade next to your or someone else's face. Especially with the wonderful even heat from a hand held torch. Jesus.

If you really feel the need to slather it with assorted waste products to 'improve' it, chances are, it won't be an improvement at all.

Like I said though, it'll make a great tomato stake. Not a total loss!

Cheers
Trev
 
CBP is not trolling Trev - he is an avid experimental enthusiast and looks at what he has for tools and materials and floats ideas. Or does it himself anyways. Or forgets to crop his pics he he he (anyone else remember that?). CBP is well meaning. No troll for sure.

Thanks Bearhunter for the information and the temperature/procedure specifics. Useful to know.

Cheers,

Cam
 
vstar650ca said:
Exactly, takes a lot of heat(in the thousand degrees where steel gets past red hot) to anneal or temper steel,what CanadianBaconPancakes is doing is what method used before chemical bluing was invented.In fact I believe but not 100% sure linseed oil was used and rubbed on with a rag on hot steel.
Click to expand...

I wouldn't say that hot. Above 400c you will start tempering it...
 
Early Lee Metford and Enfield rifles were finished with a slow rust blued barrel and an oil blackened receiver, bolt, nose cap and barrel bands.
Most of the other fittings and screws were oil blackened too as part of their manufacturing process.

I use this method to blacken small parts that will fit into an iron pan with lid. Largest thing I did was a one piece revolver frame and barrel. Very unscientific. I put a piece of mechanics wire on each piece to help me pick them up. I bring the pan up to temp for half an hour on a Coleman stove and then sit the polished parts inside on an iron plate, I put the lid on and start the stopwatch. I time exactly ten minutes and then pull them out and drop into used motor oil. I wash and scrub with soap and water then do it again until I get the black I want. Not sure as to the temperature reached, but the polished in the white metal parts are barely a straw yellow when I pull them out of the pan. If I get them too hot, the blackening will take on a dark purple tinge, which I have seen on production guns..

Possibly one reason not to oil blacken a rifle barrel is that it needs to be heated and cooled evenly to prevent distortion. Get it wrong and you will wreck the barrel by warping it. Destroy the heat treatment of the receiver, soften it or make it brittle..

Like any 'real' finish, surface preparation makes all the difference. Oil blackening although tough as nails, is not very thick and hides no surface defect.

So if you are game go for it. Do your research first on heat treatment and tempering. Just stay away from those temperatures and you will be golden.

Figuring out how to control the temp evenly and how to measure will be the challenge.
 
englishman_ca said:
Early Lee Metford and Enfield rifles were finished with a slow rust blued barrel and an oil blackened receiver, bolt, nose cap and barrel bands.
Most of the other fittings and screws were oil blackened too as part of their manufacturing process.

I use this method to blacken small parts that will fit into an iron pan with lid. Largest thing I did was a one piece revolver frame and barrel. Very unscientific. I put a piece of mechanics wire on each piece to help me pick them up. I bring the pan up to temp for half an hour on a Coleman stove and then sit the polished parts inside on an iron plate, I put the lid on and start the stopwatch. I time exactly ten minutes and then pull them out and drop into used motor oil. I wash and scrub with soap and water then do it again until I get the black I want. Not sure as to the temperature reached, but the polished in the white metal parts are barely a straw yellow when I pull them out of the pan. If I get them too hot, the blackening will take on a dark purple tinge, which I have seen on production guns..

Possibly one reason not to oil blacken a rifle barrel is that it needs to be heated and cooled evenly to prevent distortion. Get it wrong and you will wreck the barrel by warping it. Destroy the heat treatment of the receiver, soften it or make it brittle..

Like any 'real' finish, surface preparation makes all the difference. Oil blackening although tough as nails, is not very thick and hides no surface defect.

So if you are game go for it. Do your research first on heat treatment and tempering. Just stay away from those temperatures and you will be golden.

Figuring out how to control the temp evenly and how to measure will be the challenge.
Click to expand...



We found with the idlers that we had to hang them and dip them from one end. If we put them into the oil on their side they would warp as mentioned.
 
englishman_ca said:
Early Lee Metford and Enfield rifles were finished with a slow rust blued barrel and an oil blackened receiver, bolt, nose cap and barrel bands.
Most of the other fittings and screws were oil blackened too as part of their manufacturing process.

I use this method to blacken small parts that will fit into an iron pan with lid. Largest thing I did was a one piece revolver frame and barrel. Very unscientific. I put a piece of mechanics wire on each piece to help me pick them up. I bring the pan up to temp for half an hour on a Coleman stove and then sit the polished parts inside on an iron plate, I put the lid on and start the stopwatch. I time exactly ten minutes and then pull them out and drop into used motor oil. I wash and scrub with soap and water then do it again until I get the black I want. Not sure as to the temperature reached, but the polished in the white metal parts are barely a straw yellow when I pull them out of the pan. If I get them too hot, the blackening will take on a dark purple tinge, which I have seen on production guns..

Possibly one reason not to oil blacken a rifle barrel is that it needs to be heated and cooled evenly to prevent distortion. Get it wrong and you will wreck the barrel by warping it. Destroy the heat treatment of the receiver, soften it or make it brittle..

Like any 'real' finish, surface preparation makes all the difference. Oil blackening although tough as nails, is not very thick and hides no surface defect.

So if you are game go for it. Do your research first on heat treatment and tempering. Just stay away from those temperatures and you will be golden.

Figuring out how to control the temp evenly and how to measure will be the challenge.
Click to expand...
Good write up I mainly worked with tool steel as a machinist such as A2 o2 etc High carbon steel.Just wondering how much heat it would take to blacken a Enfield barrel.Thinking heating up rubbing oil. cooling then polishing with oil soaked fine steel wool then repeat would give the desired colour. Machine gun barrels such as the high Rof German MP-39's and 42's must of got to quite a temp and went through some pretty severe heat cycles made with steel of that era with out suffering metal fatigue or barrel blow ups.Now I am curious
 
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VanIsleCam said:
CBP is not trolling Trev - he is an avid experimental enthusiast and looks at what he has for tools and materials and floats ideas. Or does it himself anyways. Or forgets to crop his pics he he he (anyone else remember that?). CBP is well meaning. No troll for sure.

Thanks Bearhunter for the information and the temperature/procedure specifics. Useful to know.

Cheers,

Cam
Click to expand...

Oh, I did not think he was a troll, just that the idea isn't worth pursuing. Well, OK, it's his tomato stake!

And yeah, I really don't care for LE's of any shape or form. I do not really care so much that he ruins it, just that he not potentially hurt himself or others in his experimentation.

I have heat treated a lot of parts and pieces, and my experiences have shown me that doing it by the seat of your arse is a great way to get inconsistent and unrepeatable results. Far better to have control over your actual temperatures, as well as the medium used to quench. As many of the variable as you can, must be known, to get results more or less what were hoped for.

Cheers
Trev
 
I used to do a lot of hot oil and what we in the old days called blanket blacking. I would not recommend doing it on a receiver as it would be too easy to reach the point where you effect the heat treat on the receiver. It takes a lot of heat on a hardened receiver to get an oil blacking.
 
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