frizzen hardening

[longfowler]

OK, I must confess - I purchased a cheap replacement lock from Gun Parts Inc, and it won't spark no mater what I try. I'm sure it's a cheap pot metal Indian made lock, so I ordered a T/C replacement frizzen from Log Cabin Shop...it's a LITTLE beter, but not much. I get a weak spark but nothing like my Lyman or Dixie Grice lock...those 2 are fire hazzards! My question is, shouldn't this replacement part be ready to use? It fits the lock perfect, so I guess I'll try hardening it, but I wonder if I had ordered it direct from Thompson Center, would it have been better?

 

[J.D.]

I assume you are putting this frizzen on the cheap lock? Is the mainspring strong enough to create good sparks? Are you using a cut flint or knapped flint. Is the flint new, or maybe dull? Does the flint cut grooves down the face of either frizzen?

Will a file cut the face of the frizzen, or does it skate across leaving only light scratches behind?

I ask these questions because these issues may prevent the frizzen from sparking well. The last question relates to the hardness of the frizzen.

Frizzens can be too hard, so don't be too quick to harden a part that doesn't need it.

Lets find the root cause of the problem before doing anything rash.

 

[longfowler]

Oh, yeah, that's anonther thing I was wondering, if a frizzen could be too hard - this lock looks just like the new T/C lock, plenty of mainspring, and I have a brand new BEF in the jaws that leaves a nice gouge. I even switched hammer & frizzen onto the lyman lock, same result. just one or two weak sparks, & I can scratch the surface with a screwdriver. I wondered if anyone else has tried one of those replacement frizzens and had luck, or do I need to get the torch & kasenit out?

 

[J.D.]

Sounds like the frizzen does need to be hardened.

I don't know if TC frizzens are made of 1095 steel, or of low carbon mild steel. However,
I suggest using a reducing flame on an acetylene torch, played across the face of the frizzen until the frizzen loses magnetism. Be aware of the color, at that point, and keep the frizzen at a slightly brighter color for a coupla minutes. Quickly quench in light oil warmed to 130 degrees, transmission fluid works pretty well. I suggest using at least a half gallon of oil, to adequately wick the heat away from the part. More is better.

Clean the part of oil and scale and put it in the kitchen oven at 350 degrees for an hour. I suggest using the average reading between two oven thermometers to regulate the temp, since oven thermostats are notoriously inaccurate, sometimes varying as much as 100 degrees from the setting.

Once the part has cooled, polish the frizzen so that tempering colors will be apparent when the tail and toe are tempered to a full blue.

Slowly heat the end of the tail until the colors begin to run down the tail to the toe and across the pan cover. Once a straw color reaches the face of the frizzen, quench in warm water to stop the heat transfer. Clean 'er up and you are done.

If the frizzen is still soft, it will need case hardening. Repeat the instructions above, using Kasnite to cover the face of the frizzen for at least 15 minutes. Quench in warm water, then temper as above.

There was a good thread on hardening frizzens a coupla days ago. A search might turn up more information submitted by other folks who do this more often than I. I offered my way of hardening a frizzen, but there are as many ways to skin a cat, or harden a frizzen as there are people to do it, so check out some of the other threads on the subject.

God bless,
J.D.

 

[bingo1952]

Before you case harden it heat to cherry red and quench it 10 weight motor oil or transmission fluid and see if it hardens. If not give the kasenit a go just be aware that if done with a torch you will be hard pressed to get more than a .003 thousandths case. The same applies to an acetylene torch with a carburizing flame. The best way to get a deep case is a soak for at least a half hour in a furnace with the part submerged in molten kasenit and then water quench.