Chambers frizzen heat treat procedure

[ghostdncr]

I just received a replacement frizzen for my small Siler flintlock from Jim Chambers.

Many of you will probably know that this is only a casting that must be fit to an individual lock and then heat treated. The guy I talked to when I ordered said "Full heat treating directions will come with the frizzen" and knowing how these things typically work, I had the presence of mind to ask what material the frizzen was made of. He said it was cast from 1095.

Does anyone know, right off the cuff, what the proper heat treat process would be for a frizzen cast of 1095 steel? I'd really like to get this project moved along if at all possible.

 

[rich pierce]

I'm sure Wick can chime in here with more precise answers. First I get it as polished as it will ever be. I heat to a good hot reddish orange color with a wire in the frizzen axle hole to hold the piece and let it soak at that heat a couple of minutes, then quench while moving it around in auto transmission fluid (I like it cause it's red). Wipe it down and try to file it with a new needle file. If it skates, good. If not, you didn't get it hot enough or it didn't cool quickly enough and you'll need to harden it again. If you don't check hardness at this stage, you can't figure out later what went wrong if it is soft.

Now polish it really well and heat the axle and "stop" area to brightish blue, not beyond. Don't let the frizzen face get hot. Then cook it in the oven for an hour at 400 with a thermometer and let it cool in there. Generally, it's a fact, you need to take a little off the face with a grinder being careful not to heat it up, to reveal the highest carbon hard surface that will spark well after all this on cast steel.

 

[mazo kid]

I've built a couple of large Siler kits and at least the first one was pre-Chambers. This is what the instructions that came with the kit say about the frizzen: Heat uniformly all over to 1550 degrees (bright red)and quickly quench in about 2 quarts of 10 or 20W motor oil, moving part around in the oil until cool. If part is hard, it will not file. Tempering: Place part in oven at 375 degrees, after one hour remove frizzen and let it air cool. (Note: Do NOT quench parts in water or they may crack!!)

 

[LRB]

Rich has it down about as good as it gets for home HT of 1095 frizzens. KID, bright red to my eyes is around 1450°. Red-orange is 1475°, to 1500°, which is about right for 1095. One can go a tad higher, but the higher you go, the more chance of grain growth, which weakens the steel. In any case, I would suggest a sub-critical heat cycling, maybe 2, to 3 times before bringing up to quench heat. This will not only stress relieve it, but also cause the grain to be smaller, making the frizzen stronger, and less likely to ever break. Sub-critical would be a reddish phase, in dim light, just short of going non-magnetic. Let it cool to room temp between cycles. One other thing I would bring up is that Chambers recommends 375°as the temper. I would suggest that be given a trial run, and if you think it not enough, then go on up to 400°. I would not go over 400° though.

 

[J.D.]

Wick is the resident expert on heat treating, however, I have done some heat treating too. :wink:

Chambers recommends heating the face of the frizzen with an acetylene torch producing a carbon rich flame. Jim says the carbon in the flame will add some carbon to the surface of the face of the frizzen to offset loss of surface carbon at hardening temps.

Heat until a magnet refuses to stick to the metal, taking note of the color, at that point. Nonmagnetic is about 1425 degrees, so ya gotta heat the frizzen to a deeper red to red orange color and hold that color for a few minutes. Quickly quench in a light oil, I use transmission fluid, heated to 130 degrees.

Test with a file, then clean off any scale and polish enough that colors will be evident.

Temper for an hour at 375-400 degrees, using the average temp between two oven thermometers, since the thermostat on kitchen ovens is notoriously inaccurate.

Once the frizzen is cool, slowly temper the tail and toe to a full blue color, allowing the color to run across the pan cover, almost to the face of the frizzen.

That should do it.

Dang Wick, we must have been typing at the same time, only you finished first. Good information though.
God Bless, J.D.

 

[paulvallandigham]

Just an additional thought on this process. I recommend you use 2-cycle, lawn mower oil in SAE 30 weight, rather than the multi-viscosity Motor oils, that contain detergents and other additives for cars. Either this, or the auto transmission fluid should be heated to harden the steel without the threat of cracks. I do like Wick's suggestion of bring the piece up to near hardening temperature a couple of times, and cooling back to room temperature to shorten the grains. And, at one time, Wick also recommended tempering the frizzen at the oven temperatures( 375 degrees) 3 times to better temper the metal. That seems to take stresses out of the steel, so that it is tough, and hard enough to spark well.

The separate heating of the toe of the frizzen to blue makes a lot of sense, J.D. That is needed to make that part soft enough to not crack or break under the stresses of being flipped open when the lock is fired. If you hold the frizzen in vise grips on the top and face of the frizzen, the vise grips will act as a heat sink, so that heating the toe of the frizzen to blue will not affect the temper of the face of the frizzen.

 

[Tumblernotch]

I've built a couple of large Siler kits and at least the first one was pre-Chambers. This is what the instructions that came with the kit say about the frizzen: Heat uniformly all over to 1550 degrees (bright red)and quickly quench in about 2 quarts of 10 or 20W motor oil, moving part around in the oil until cool. If part is hard, it will not file. Tempering: Place part in oven at 375 degrees, after one hour remove frizzen and let it air cool. (Note: Do NOT quench parts in water or they may crack!!)

I too have tempered the older Siler frizzens. Bud always put instructions in with his parts. According to the old instructions I have, after hardening in oil and cleaning the frizzen you place it on a bed of clean sand about 1/2 inch thick that is on a metal lid with a lip on it to keep the sand in place. With is method you can temper any part on a kitchen stove burner and that's what I've done. When the frizzen turns a straw color, remove and allow to air cool. One rifle I have is 19 years old and the frizzen sparks as well as ever and has never been re-hardened or tempered.

 

[Ian Pratt]

Couple things I'd add - I use about a gallon of ATF for the quench, bigger volume of oil helps insure a proper hardening, also pack the frizzen in a can of sand to draw it back in the oven - some ovens have wild temperature spikes and the sand helps keep your temperature consistent. Soup can will work for this.

 

[ghostdncr]

Thanks for all the input! Work has conspired to keep me from getting the frizzen fitted as fast as I'd hoped, but it won't be long before this info becomes necessary.

Would pictures of the entire fitting and HT process be helpful to anyone?

 

[mazo kid]

Well, see what happens when a question gets asked? The people who know what they are doing will respond . I only posted what the instructions of long ago said; and I am glad to see that I may have room for improvement the next time I do this. I have absolutely no steel hardening experience except"seat of the pants" type....either it gets hard or I have to try something else.