Trouble anealing Trigger guard

[wvmtnman]

Last night I attempted to aneal a trigger guard so that I could stretch the bow a little to allow for set triggers.  I put the guard in a wood fire, when it was red I took it out and put it in a bucket of water.  I picked it up and noticed it was cracked in the rail.  I tried to bend it a little and it tore apart.  I put it in a vice and tried to bend it and the same thing happened anywhere I attempted to bend it.  Did I leave it in the fire too long?  Sould I have not heated it in a wood fire?  Was the brass bad?  I have no clue what went wrong...
                                                             Thanks, Brian

[jerrywh]

wvumtnman@verizon.net
  How long was it in the fire? Where did you get the trigger guard?

[northwoodsdave]

I may be wrong, but isn't annealing to soften metal?  If you put the red hot metal  into cold water, you didn't anneal it, you were tempering (hardening) the metal.

When I anneal steel, I heat it then wrap it in high temp insulation and let it cool very slowly so it remains soft.  I think you wanted to heat the brass, but then let it cool slowly to take out the hardness. 

I'm sure others here will have more information

David L

[490roundball]

Steel anneals with a slow cool down and hardens with a quench- 


but it has always been my impression that to anneal brass it's backwards - heat and quench to soften - at least I have been lucky, its worked for me.

Rick

[Randall Steffy]

wvmtnman,
Based on my experience water quench is optional and not necessary except to allow you to keep working without pause. Some alloys do not seem to anneal well and I suspect you had such and also overheated your casting both temp. and time wise. It would be interesting to know if the cracks were present before or only after the quench.
I never heat above the dullest of reds to anneal brass and preferably lower, where the brass loses it shine and becomes dull from the heat.
I feel your pain.

[David Rase]

Some of the castings available contain too much bronze and/or other alloys and no matter how many times you anneal them they will never be malleable enough too draw out without cracking.   I had a brass butt plate I tried to widen by about 1/8" about a year ago.  It was a sand cast butt plate.  I was very careful and annealed it quite often during the drawing out process but it still ended up full of cracks.  I ended up using it as a pattern, built it up a little and cast my own. 
If I remember correctly, Taylor stretched an Armstrong triggerguard by cutting it apart,  soldered in a piece and then filed and polished it out.  You might check the archives or Taylor might repost his process for you.
DMR
 

[Z. Buck]

non ferrous metals definitely need a quick cool to anneal, however like was mentioned sometimes they are well finicky to say the least. like someone else mentioned, just heat till dull, and allot of times just lay it on a cold chunk of steel or the like to cool water not necessary, i found sometimes a squirt bottle set on mist will cool it down fast enough to get the best results without overdoing it. and as far as annealing and stretching i dont think you could go wrong with reeves goerhings stuff, otherwise, you might want to go the sapergia route and pin, braze, solder method (i dont remember exactly what he did but i remember it was one of the best looking fabrication/ rework jobs ive seen

[bob in the woods]

I have had that happen to me, but the buutplate I tried to anneal was probably bronze, not brass.
The nice brass stuff is a joy to work with, and I have not had any trouble annealing it. If you leave it in the wood fire ...too hot for too long, could you have cooked the zinc out of it??? I'm not sure if that could be the problem. It was probably just the material itself.

[northmn]

Another thing about annealing or tempering metal using water.  You should have the water about 150 degrees minimum.  Cracking and that sort of thing can occur either from tempering water cooled or annealing because the water was too cold.  Fresh hot tap water can work.  The only time I use cold tap water is with a cast bullet taht I wish to harden.

DP

[LRB]

  Mr. Rase has the most probable answer to your problem. NO, you do not harden brass by water cooling it, but rapid cooling is not necessary to anneal it.  Just an option. The only way brass hardens is by being worked. Slow cool, fast cool, makes no difference with brass in the anneal. The heat needs to be no more than a dull red heat. Too high in temperature can  cause problems.

[jerrywh]

almost everything the guys said is true but , without knowing for sure what you have, how long it was in the fire , how hot it was and   where it came from, every answer is just a guess.
  Good guesses, but guesses.  You never even stated if it was steel or brass.

[wvmtnman]

Sorry, I guess I did not state that it was a brass guard but in the last line I asked "was the brass was bad" and thought that those who read the posting would figure that it was a brass casting.   The casting came from Track and I removed it from the fire when the bow became a dull red.  The exposed area of the crack sort of looks like the stuff that is skimmed off lead when it is melted, but a different color.  Like there were many impurities in the brass.  As for the water, it was room temperature.  The only experience I have with anealing is sheet brass when I am making ram rod pipes.
                                                                           Brian

[jerrywh]

 From what you say I don't think you did anything wrong. Some castings just won't anneal. In my opinion that was either a defective casting or it was silicon bronze. When brass is poured at too hot a temperature it will be defective in structure and cannot be annealed. Also there is a such thing as Hydrogen embrittlement. It is caused from the metal picking up impurities from the furnace fire. Casting defects will sometimes make good looking castings but they will be brittle and can never be annealed no matter what you do. Sounds like you got one of these.
  Also. the crystal structure of brass can be altered by long time exposure to temperatures over 500 deg fer. This will cause the same thing as is sometimes called age embrittlement. Old castings [ 100 years old or so ] will become brittle from age. The structure of brass changes with age just as it does under long time exposure to high temperature. these conditions cannot be rectified by annealing.
  If you try to bend a brass casting and it feels like it is springy and wants to spring back more than likely it is brittle and more than likely it cannot be annealed.
 A normal casting of soft brass will not be springy to begin with.  If it  is , something is wrong.  If it is off an old antique gun  never try to bend it. That is my advise for what it's worth,

[Dphariss]

I agree with Jerry.
If it was brass your process should have annealed it to dead soft. However, there are a lot of parts out there that are NOT brass even though they look a lot like it. Bronze is far different than brass and is very difficult to work. Wax castings are more likely to be bronze than sand castings it seems.
I get the feeling a lot of the castings we get are coming from the third world.

Dan

[Acer Saccharum]

reaves castings are butter soft, and you can work them all over the map. Hammer out, stretch, peen, bend, all day long.

Try that with a wax cast bronze guard. Just a slight bend is enough to crack the casting sometimes. Even tho the color looks like brass, the stuff does not anneal, nor does it hammer out. Hard as heck to file, too.

Acer

[jerrywh]

It really doesn't matter if brass is cast by the investment process or sand cast. If it is the same alloy it will come out with  the same properties if both processes are conducted properly.
  The problem is a lot of casters are using silicon bronze instead of soft brass. I once purchased some brass from a foundry supply only to find out later that they had substituted silicon bronze. It cost me thousands of dollars worth of labor and material. I recently noticed that the bars are marked with a large letter S on them.  Now I use them for weights and door stops. The castings looked beautiful. I dropped one of the butt plates on the floor and it broke into three pieces.

[northwoodsdave]

Well, I for one have learned a whole lot about brass and bronze.  My background is ironwork, so this has been a good lesson.

What say we all get together and buy poor Brian a new triggerguard.  I'd put five bucks in an envelope for him.

Any takers?

David Lowe

[wvmtnman]

I appreciate the offer but I already have a new trigger guard on the way.  I have also decided to scrape the idea of set triggers on the Beck project.  In fact, I am going to use my .38 caliber B weight barrel and use the .42 caliber barrel to copy the Benson that is pictured in the virtual museum.  I really like Benson rifles and have seen a great number of them.  They were made not too far from where I live.  Most are still in family of the original owners.  I have been trying to buy one for years but not too many people are willling to let them go so I guess I will have to settle for a copy.  Anyway, thanks to all who replied and helped out.  I will not need this information at the present time but I am sure that I will need it in the future.
                                                                      Brian