Lock builders questions

[greywuuf]

Hello guys ...I have a couple of old locks (flint) and many of the parts are worn and rough, mostly the pivot holes are wallowed and screws are worn. My plan of attack is to use bronze bushings (oilite) and make new screws ....the thing I am noticing though is that the back (inside) face of the locks are not flat.....I mean one seems to have a bow and the other is markedly wavey. I am a fairly experienced hobbyist machinist and spend a number of years professionally building performance engines....and it just seems to me that to get the best most reliable operation from any mechanical device a referance point is needed. It seems that if the inside face of the lock plate was dead flat it would be a much better starting point (perpendicular holes for pivot pins and square contact of Sears and levers would be markedly easier)...I am not suggesting fly cutting the inside of the plate .. but I think at least some lead hammer/surface plate file work may be in order....  Am I completely off base or is the lock plate supposed to be flat, and mine are all just damaged/beat up.

[Mark Elliott]

You are right that it would be best that they be perfectly flat, but a lot aren't.    If you case harden the plate, then it is going to warp some.   Are these plates surface hardened?   If they are, that might explain the bow and wave.  Also,  are these antique or relatively modern locks?

[greywuuf]

Both are antique..   one is an 1804 marked Barnett India pattern Bess lock and one is a unknown later lock that has been converted to percussion ...  I have no idea if they are case hardened or not.... Neither displays the coloring the converted one looks pretty much like a modern kit lock.. but it is well used with a collection of "authentic" smooth bore parts and had the frizzen spring holes that have been filled ...leading me to believe it is an old conversion (drum screwed into the vent and the cock changed out)

[greywuuf]

For example ..  this is the Barnett

[retired fella]

If you are building a new gun why would you want to put old, worn parts in it?  Sounds like you would be doing more fixing than shooting. 

[greywuuf]

Well, there are a couple of reasons. I am building a gun. Why would I do that if all I wanted was to shoot a gun?     Second if I were do buy a set of lock castings (again building a gun, not bolting someone else work together and not simply stock carving......wood working is quite honestly my least favorite part of guns)....I would do pretty much all of the same things and three if the lock does not work correctly what good is it? ....it made it 200 years I am not going to be the one to toss it out because it is old or broken.....thanks though for the otherwise un helpful comment.

[rich pierce]

Sounds like a fun and challenging project that will diminish collector value while increasing functionality. Im sure you know that any parts that function together adequately now while things are wavy or warped, probably won't after straightening.  Most locks were case hardened then polished. Easy to check. As such, easily straightened with a dead blow hammer on a lead block.