Reounding Frizzen Troubles

[David R. Pennington]

Does the frizzen spring need to be stouter? It rebounds against the top hammer jaw leaving a little mark. Otherwise works fine.

[D. Taylor Sapergia]

Generally, yes.  You can accomplish that by removing the feather spring from the plate, heating it red while holding the spring by a wire, and increasing the arc of the top leaf...about another 1/8" is lots usually.  Now polish the spring, heat red while it rests on a fire brick, quickly swirl it in oil 'til cold (figure , I run a piece of iron wire through the screw hole for a handle,  re-polish, temper.

[Long John]

David,

I ALWAYS listen when Taylor offers advice or opinion, ALWAYS!

Another thing you can try is to use a file and adjust the apex of the cam on the foot of the frizzen a little further forward.  Many locks are made with frizzen spring tension that is too great, in my opinion, and adjusting the cam forward a little both lessens the force applied to the frizzen and also reduces the tendency to bounce back.

A second adjustment is to use your file to reduce the stop on the frizzen that limits how far the frizzen can open.  Many original guns, especially the French guns I have, the frizzen opens until the pan-cover part of the frizzen is completely vertical or actually leaning a little forward of vertical.  This puts more of the frizzen weight forward and reduces the tendency to pop back.  The popping back is caused by the frizzen stop forcing the feather spring down from inertia and then the feather spring forcing the frizzen back.  By relieving the stop and allowing the frizzen to move further forward there is more frizzen mass working against the feather spring, reducing the snap-back phenomenon.

I hope this helps.  But remember, I am a hobby builder, not a professional.

Best Regards,

JMC
John Cholin

[BOB HILL]

Thanks for these tips,fellows. Good to know. Seems like I learn something here everyday.
Bob

[wmrike]

My most-used lock did that at the outset, off and on for, I'm guessing, maybe the first 150 shots, then shook it off.  That was 14-15 years ago.  I have no idea what changed.  I doubt the spring got stronger.  There's no corrosion or galling, or obvious wear that would slow the frizzen in the undertaking of its everyday business.

[David R. Pennington]

Thanks guys. I will try re arching and harden and temper frizzen spring. It does seem a little weak. 

[Pukka Bundook]

David,

If you want to test the spring before working on it, jam a piece of leather tightly in the "V" of the spring. this will toughen it up, and tell you whether this is what is required.

Best,
Richard.

[David R. Pennington]

Well, I heated the spring, opened it up a wee bit and flattened the arc out just a little on the tail end. Re hardened and tempered and works fine now with no rebound. I tested with a little ball of clay and no sign of rebounding contact.

[rich pierce]

Good fix!

[flehto]

My first LR used a small Siler lock which limited flint length at half cock and after some wear on the flint  the frizzen wouldn't  toggle over. This was in 1978 and possibly the small Siler that Chambers sells has the problem corrected.

Whether the problem was a failure to toggle over the frizzen  or rebounding of the frizzen had to be determined. It was found to be failure to toggle over.

So this is what I did to stop the failure to toggle over. . Put the flint edge {chamfer up} at the bottom of the frizzen striking surface and marked the position of the frizzen toe on the frizzen spring.  Then took a Dremel w/ a small dia grinding wheel and ground a relief on both sides of the mark and formed a hump or cam which was .015 high. The hump and surrounding areas were then highly polished.

Frizzen then toggled over w/o fail even w/ short flints and w/o having to heat treat the frizzen spring......Fred