Induction Annealer - Almost Done!!!

[Rtheurer]

Jstn

Are the lights on? Turning the light off so that you can see the glow without any ambient light in the room seems to work and is what Steve Blair is talking about.
I don't see the glow in the light of the room, Turn the lights off and its like Steve points out, just a tiny dark dull red glow, not a bright orange glow.

Mr Berg. Kinda wild that your brass turns NO color at all using induction proccess. Intresting.

RussT

 

[jsthntn247]

Jstn

Are the lights on? Turning the light off so that you can see the glow without any ambient light in the room seems to work and is what Steve Blair is talking about.
I don't see the glow in the light of the room, Turn the lights off and its like Steve points out, just a tiny dark dull red glow, not a bright orange glow.

Mr Berg. Kinda wild that your brass turns NO color at all using induction proccess. Intresting.

RussT

I've tried it with the lights on and off and the only red neck in the room is still me.

 

[markm87]

I've tried it with the lights on and off and the only red neck in the room is still me.

;D

I've done the low light method too over the years... to establish a baseline est of how much flame time I need for a given kind of brass. (I find that time varies as you change brass because of thicker necks)

Anymore and I just run 6 to 7 Mississippi and fine tune from there based on what I'm seeing.

 

[missed]

I have a pile of parts ready to build one also, but I think I bought the parts a year ago..... I keep thinking about an automated rig that has a case feeder, deprime/resize, then anneal....Then the only thing I will have to do is dump brass in, push the go button, drop it right into the stainless tumbler!

 

[1066]

Mr Berg. Kinda wild that your brass turns NO color at all using induction proccess. Intresting.

RussT

In my experience using the colour change to indicate correctly annealed brass is a risky business.
If I clean a batch of cases with SS media then anneal some of them straight away, I often get virtually no colour change. If I anneal the rest of the same batch after they have been standing around for a week or so I often see the classic "Lapua" look.

Obviously natural oxidation is playing a part in how the cases look.

When you are annealing cases you may see the colour of the flame start to turn yellow, this is caused by the zinc content of the brass starting to vaporise, this happens at 787f.

IMO To achieve a good stress relieving anneal we want to be over 650f and below the point where we melt the zinc (787f) - cases that have exceeded this temperature will have a dull coppery look as the surface molecules of zinc have burnt off. Going over this temperature by a hundred degrees or so won't hurt the brass unduly, I just think it's unnecessary.

My method is to time how long it takes the flame to change colour then back off the time by 10%. Say, using a single pencil flame, it takes 9.2 seconds to the yellow flame, reduce the time by .92 secs. (I would round that to 8 seconds)


The time it takes is dependent on the flame intensity, type of brass, distance from flame, type of gas used etc. Ambient temperature will also effect gas pressure unless a pressure regulator is used.

I'm no expert, just my observations:

My annealer:



in action:
https://www.youtube.com/watch?v=Jv75-9p9yFA

 

[missed]

oh yeah what is the power output on yours? My calculations are showing that for up to a lapua 338 magnum I would need 1kW to anneal that case in a second. I figured the quicker the better to reduce the heating down the shoulder.

 

[itchyTF]

I believe mine is capable of 1,200W. I haven't played around with larger cases yet so I don't know what the "burn" time will be. But I'll get there!

 

[snakepit]

Anymore and I just run 6 to 7 Mississippi and fine tune from there based on what I'm seeing.

Here is another method that works for me, jut turn your speakers up:

http://a.bestmetronome.com

 

[CatShooter]

In my experience using the colour change to indicate correctly annealed brass is a risky business.
If I clean a batch of cases with SS media then anneal some of them straight away, I often get virtually no colour change. If I anneal the rest of the same batch after they have been standing around for a week or so I often see the classic "Lapua" look.

Obviously natural oxidation is playing a part in how the cases look.

These two groups of Remington cases were annealed at the same time, same temperature, same everything, but one had just been washed and polished (don't remember which one)

When you are annealing cases you may see the colour of the flame start to turn yellow, this is caused by the zinc content of the brass starting to vaporise, this happens at 787f.

Not true - Zinc does not vaporize at 787 F. The temperature that Zinc vaporizes is 1665 F., and that is only when it is in it's pure state - when alloyed with copper, it is much higher, You cannot burn or vaporise Zinc from brass cases.

http://www.stevespanglerscience.com/lab/experiments/flame-test

The yellow you see when annealing is the carbon in the ash deposits at the mouth - The color of Zinc in a flame is Blue-ish green, which is the same flame color as copper, so you cannot tell the difference.

IMO To achieve a good stress relieving anneal we want to be over 650f and below the point where we melt the zinc (787f) - cases that have exceeded this temperature will have a dull coppery look as the surface molecules of zinc have burnt off. Going over this temperature by a hundred degrees or so won't hurt the brass unduly, I just think it's unnecessary.

You cannot melt the Zinc that is in a case, no matter what temperature.

 

[Syncrowave]

You cannot burn or vaporise Zinc from brass cases.

Ever tried it? I have with a TIG torch and I assure you the zinc vaporizes and leaves a white powder (zinc oxide) on what's left of the brass (mostly copper) and also makes a mess of your tungsten.


This is why it's darn near impossible to weld brass.

 

[Steve Blair]

This is why it's darn near impossible to weld brass.

[br]
I've had both pure copper (oxygen free) and lead free Naval Brass welded. TIG is not the right way to do it. The primary problem is thermal conductivity, not alloying elements.

 

[CatShooter]

You cannot burn or vaporise Zinc from brass cases.

Ever tried it? I have with a TIG torch and I assure you the zinc vaporizes and leaves a white powder (zinc oxide) on what's left of the brass (mostly copper) and also makes a mess of your tungsten.


This is why it's darn near impossible to weld brass.

You are comparing TIG with a propane torch???

You gotta be kiddin'.

We are talking about annealing brass cartridge cases - you are on the wrong forum.

 

[Syncrowave]

This is why it's darn near impossible to weld brass.

[br]
I've had both pure copper (oxygen free) and lead free Naval Brass welded. TIG is not the right way to do it. The primary problem is thermal conductivity, not alloying elements.

I can tig weld copper all day long. And copper is more thermally conductive than brass.


And yes, you can drive off the zinc from brass with propane.

 

[markm87]

Simple chemistry. There is no oversupply of oxygen with induction annealing so there is little if any oxidation in just a few seconds. With a torch using the oxidizing flame (the pointy bright blue one in the middle of the clear blue neutral flame) the brass turns color (oxidizes) very quickly.

That's interesting. I wonder what method, for example, Lapua uses. I mean... their brass has a remarkable annealing iris on the neck/shoulder.

I'd assume they have finely tuned induction annealers.

 

[amlevin]

I wonder what method, for example, Lapua uses. I mean... their brass has a remarkable annealing iris on the neck/shoulder.

Simple answer. A big expensive machine that none of us could afford.

 

[Webster]

A simple way to tell if you have over annealed the case is to squeeze the neck with pliers. Use range pickup brass or junk cases. If it's way over annealed you can collapse the neck with very little effort. Compare the force needed to close an un-annealed case neck. With a single flame handheld torch I have been annealing ten seconds. I think the neck heats up much faster than the shoulder. I push the case into the bright blue pencil point to disrupt the sharp flame point and spread it out. Looks like a lower temp than using the pointed hot blue. It takes 21-22 seconds with this set up to see the case start to turn orange. With ten seconds the neck still has a lot of resistance to closing the case mouth with pliers. I disagree with some of Ken Lights statements. I have been doing metallurgical failure analysis for 45 years. The cases are not ruined if you go a few seconds to long. Use the plier crush test. 15 seconds at 800F gives a very small loss of hardness.

 

[CatShooter]

A simple way to tell if you have over annealed the case is to squeeze the neck with pliers. Use range pickup brass or junk cases. If it's way over annealed you can collapse the neck with very little effort. Compare the force needed to close an un-annealed case neck. With a single flame handheld torch I have been annealing ten seconds. I think the neck heats up much faster than the shoulder. I push the case into the bright blue pencil point to disrupt the sharp flame point and spread it out. Looks like a lower temp than using the pointed hot blue. It takes 21-22 seconds with this set up to see the case start to turn orange. With ten seconds the neck still has a lot of resistance to closing the case mouth with pliers. I disagree with some of Ken Lights statements. I have been doing metallurgical failure analysis for 45 years. The cases are not ruined if you go a few seconds to long. Use the plier crush test. 15 seconds at 800F gives a very small loss of hardness.

You test annealing with PLIERS?? Very scientific.

What hardness scale do you use?

Of course you can crush the neck of an annealed case with less force than a non-annealed case.. That's why you anneal them!... to make them softer.

 

[Webster]

I suggested using pliers to test only for over annealing (approaching dead soft) or approaching to soft. Dead soft is the lowest hardness that can be obtained by annealing. I am not suggesting you can determine an accurate hardness with pliers. You can anneal to almost any hardness level. Over annealing would give very little neck tension. You can’t measure actual neck tension with a micrometer. A micrometer just tells you are consistently arriving at the same tension for the anneal you put on the neck.

I had all of the metallurgical equipment needed at work and I used it. I am retired now. One important thing to remember it’s not possible to hold at temperature. TempLaq only tells you when you reach a temp. That's why it's called flash or rapid annealing. For this reason I would determine how long it took to anneal to a light red color in a dark room and call this a little too hot. Back off on the time.
This will be about the fourth time I have put this data on the website (attached below). I wish I would have done five sec at temp. I think I assumed that because of the brief time to reach temp I would do longer times. Five minutes shows very little hardness change. At work I annealed samples in a laboratory furnace controlled to +/- 2F. I cut the necks off of Lapua 6BR cases attached fine Nichrome wire to the pieces and lowered them into the furnace through a ½” opening in the furnace roof. They were annealed at various temp and two times. The pieces were cross-sectioned embedded in epoxy and polished until they had a mirror like finish. Because the pieces have very little width I determined the hardness with a Leitz microhardness tester and converted the hardness to Rockwell “B” scale values. The samples were next etched with a reagent to show the grain boundaries. None of the many samples had a change in grain size regardless of the time or temperature.

Make what you want from the attached graph. It’s real data. 5 minutes very little hardness change at about 800F. No grain size change.This implies stress relieving more than annealing?

Like Dave Berg said I keep telling myself to stay off this website because of all of the pissing matches and BS.

 

[TC260]

I wonder what method, for example, Lapua uses. I mean... their brass has a remarkable annealing iris on the neck/shoulder.

I'd assume they have finely tuned induction annealers.

I don't know what Lapua uses but here's a few videos of manufacturer's using gas flames for annealing.

http://www.youtube.com/watch?v=7h_D3Vm17uo

http://www.youtube.com/watch?v=mE2TnpFw2v8

http://www.youtube.com/watch?v=5XhOSXD-VKE

 

[itchyTF]

I managed to get a video of the heater although I don't think it will win any academy awards. Not the best, but something -

http://youtu.be/yFOg9aDiYlk