L&R Colonial Lock Sear Screw

[Nhgrants]

I am working on this left handed lock.  The screw that goes thru the bridle and the sear and into the lock plate does not have a shoulder on it.
If the screw is tightened it will prevent the sear from rotating.  So after polishing the surfaces, I tightened the screw and then backed it off so the sear can move.  Is this typical?  It seams that this would be a good application for a shouldered screw.
Thanks 

[Bob Roller]

It can be on a production lock.The locks I used to make unless it's a
3 or 4 pin design European type that uses an axle with no threads
will have a stub thread sear screw that stops when tightened and
can't foul the sear between the bridle and the plate.There is no real
danger involved by turning the screw back  until the sear JUST functions
and on most assembled locks this id the way they are made. With CNC
now involved there should be none of this poor fitting ever seen.
Bob Roller

[Craig Wilcox]

Bob, would that require some of that green thread locker to prevent it from backing out or tightening the screw too much?
I don't have a lathe, or right now even a drill press, but I think I would just make a new screw with the shoulder in the right place.

[Stophel]

I almost always have to make new screws, particularly the sear screw, no matter what lock it is.  Not unusual.

[D. Taylor Sapergia]

This is a problem you'll find on most commercially available locks today.  There is one thing that you can do without turning a new screw, without a lathe.  If you have a drill press, or even an electric hand drill that you can strap to your bench to act as a 'poor man's lathe', set the screw in the chuck with enough of the head and shank exposed that you can slip a fine SAFE EDGED file between the chuck and the screw head.  Dress the thickness of the nead down a few thou and try it in the lock.  Continue removing steel from the inside of the screw head until you're afraid to remove anymore,m or until the screw will bottom on the lock plate without  squeezing the bridle against the sear.  You are limited with how much you can remove, but I have saved a few locks in this manner.  Otherwise, make a new screw.  Again, you don't NEED a lathe;  a drill press and files will suffice, but a lathe makes it easier and more precise.

[Stophel]

That will work, but probably not with an L&R screw!  Unlike any of the rest of their parts, their screws are rock hard, through and through! (and somewhat brittle and prone to breaking).  I've not had a whole lot of luck annealing or tempering them down, either.  I swear, they're solid carbide.

[Jim Kibler]

Screws of improper threaded length have been par for the course.  One of the things on locks that has bothered me over the years...

[Bob Roller]

Bob, would that require some of that green thread locker to prevent it from backing out or tightening the screw too much?
I don't have a lathe, or right now even a drill press, but I think I would just make a new screw with the shoulder in the right place.

I know nothing about thread locking compounds.I drill the sear screw hole with a #43 drill and then tap it
to 4x40 or 4x48.I then drill about 1/3 of the threads out with a 7/64 drill and the make the screw .109 to .110.
Hole in the sear is drilled and reamed .1105.I have never thought L&R quality control was where it should be
but then maybe the assemblers have little or no real machine shop experience and the concept of precise parts evades them.

Bob Roller