Lock sparks 3 out of 5 timmes...

[jm190]

OK, so I went back to the drawing board...

I tried resurfacing the frizzen and a regular file would not remove any material; just made it shiny. I used a diamond file and was able to achieve a fairly smooth surface. After re-installing the frizzen it set off the primer 15 out of 16 times. It was then that I noticed a small shiny spot on the very front edge of the top jaw! Moving the hammer through it's range of motion manually the top jaw was contacting the frizzen along with the flint. The flint is the proper size for this lock, 5/8" x 3/4", so I replaced the leather with a thicker piece. I got ten out of ten on the next attempts. Here's a picture of the frizzen...I'm thinking it's still a little soft by the marks left by the flint.


I'm going to take all the suggestions here and heat treat/temper the frizzen again.   Thanks for all the help!

John   

[rich pierce]

I’d just use it. The-re-re-heating frizzens that already have issues is rarely helpful.

[D. Taylor Sapergia]

You are wise not to remove any more material from the frizzen's face, than you have to.  But a bench grinder with a 6" stone is about perfect for that job.  Just don't go crazy.  At 15 flashes for 16 tries, you may already be there.

[Daryl]

Scratches happen - the flint shaves off steel, heats it incandescent in the process. If no scratches happened there would be NO sparks.

[Dphariss]

Heat to bright red in subdued light with a wire through the pivot hole. Quench in warm 100-150 degree light oil like ATF maybe with a good dose of marvels mystery oil to thin it a little more.  Clean off all the oil, polish, put in  preheated 375 degree oven using two oven thermometers for about an hour. When cool clamp sheet brass to the face, clamp another or a pair of brass scraps to the foot well below the pivot. Heat the area above the pivot to dark straw, blue. Keep heat off the brass heat sinks.  This should keep the foot and face from getting too hot. I use vise grips to clamp the brass.

Let cool. Also if you have not tried it, turn the flint over so its right side up.

I was having fits with a small siler of unknown make, slow, missfires etc. I finally did the 375 in the oven and then actually bent the cock "neck" to change the angle of the flint to the frizzen and the flint points at the pan. Fixed.... BTW my frizzens are all cut up and grooved.

Dan

[Long John]

That frizzen looks too soft to me. 

My first reaction would be to yank the frizzen heat to tangerine orange and quench in room temperature diesel fuel or canola oil.  Test with a file and make sure the file skates off the frizzen face.  If not, reheat to orange and quench again.  If the quenching oil is too heavy you will not get a good hardening.  Polish the frizzen face and heat the pivot in a propane torch and watch for the colors to migrate slowly towards the face.  When the face turns canary yellow quench in canola oil.

That's what I would do if it was my lock.  I've made a bunch of those and they all spark like the 4th of July.

JMC
John Cholin

[sqrldog]

Call Jim Chambers when he carbon packs and heat treats some frizzens he probably would include yours for a small fee.

[Mr. Bubbles]

Sounds to me like you are there,  The re-facing seems to have gotten you down to where there is more carbon in it.  As far as the top jaw goes, yeah yu might have to file it a little.  Just be aware of it so that the leather doesn't stick out beyond it and you should be ok.  If it ain't broke, don't fix it.

[JCKelly]

15 ot of 16, then 10 out of 10 and you are going to re-heat treat it??

Just to add one more dumb idea, have you tried your flints bevel side down? Or up, whatever you don't do now? fwn?

[Daryl]

You can also adjust that flint out a bit for proper contact.
This is normal practice.