Fly Question?

[Halftail]

You might already know about the thread where I have been "into" the innards of my lock.I'm curious to the function of the Fly?I thought I heard somewhere that the Fly was for a "set" trigger?
Not sure if this should be posted here or the Flintlock forum but I figured that the wealth of experience would be in the builders forum.

 

[Treerat]

It keeps the sear nose from going into the half cock notch when fireing. The typical universal set trigger rear bar only flips the sear bar then falls down,hence the need for an interruptor(the fly). Some set triggers do not require them but with these type triggers you have to have them set to cock the gun.
bill

 

[Halftail]

Thanks TreeRat :thumbsup:

 

[LRB]

Do NOT alter the fly. If the fly is somehow the problem, and with L&R's it is not unusual, take it to somebody who knows what they are doing.

 

[Roy]

The fly not only stops the sear from going back into half cock, but allows for a better trigger pull when using set or a single pinned trigger.

 

[Zonie]

As the others have described what the fly does I won't go into that except to say your first thought is basically correct. It is required for set triggers to release the sear reliably but it also assures that a simple trigger will always release the sear without any chanch of it hanging up on the half cock notch.

A thought on some of the L&R locks:
Folks who are dissassembling a L&R lock need to pay special attention to the way the fly is installed. It is not symetrical and it can be installed upside down.
If the fly is installed upside down, it won't work correctly and the sear may start to re-engage the half cock notch as the hammer falls.
The L&R locks I'm refering to have a small flat sheet metal fly with a tiny hole in it. This hole fits over a pin that is cast into the tumbler.

It is well worth taking the time to draw a picture of how the fly is installed placing special emphasis on the high lobes location relative to the notch the fly sits in. :hmm: