Making Lock Waxes — Shooting Wax!

[Hudnut]

From the original part used to make the die to the steel casting, there is shrinkage.  It might be an idea to produce waxes that incorporate extra material allowing for fitting.  If no provision is made for fitting, the castings will not go together as well as they did in the original.  Any sins in the original will be carried over into the copies, only worse.
Here are a couple of trade gun locks I set up many years ago.  The lower lock was assembled using castings from my dies.  The upper lock uses a lockplate from the Upper Missouri Trading Company completed with my castings.  I believe they used the same original lock as I did, borrowed from the Museum of the Fur Trade. The other photo shows one of my locks in a gun; markings were die stamped.  The markings in the Upper Missouri lockplate were cast in.  My dies were cast epoxy.  The springs and frizzens are 6150.  Those springs were made over 50 years ago, and are as good as when they were new.
If you have ever seen a John Clark Toronto flintlock, his dies were machined aluminum, with fitted aluminum slides.  Beautiful dies, beautiful castings.  But the dies were very costly.

[PhDBrewer]

Parts that you might want to build up are the bearing surfaces on the tumbler. Then one can turn the tumbler to the correct size.  Hard to add material later. Usually a couple wraps of masking tape on the original seems to work well to build up the surface.
Or possibly the frizzen & pan where you want to "file to fit".
Hope that helps.

William

[Hudnut]

Parts that you might want to build up are the bearing surfaces on the tumbler. Then one can turn the tumbler to the correct size.  Hard to add material later. Usually a couple wraps of masking tape on the original seems to work well to build up the surface.
Or possibly the frizzen & pan where you want to "file to fit".
Hope that helps.

William

Exactly! 

[Jim Kibler]

Another is the top of the pan and underside of the frizzen.  There are a good number of other places as well.  Basically anywhere you want to fit one part to another.

[Bob Roller]

I have seen locks that seem to have the tumbler made from wax.Dead soft steel was the real problem.
I once was asked if I could use aluminum in a lock and I told this man I was aware it existed but no idea about  how to use it in a lock and still don't.One of the L&R guys told me years ago that foundries were the big bug in the soup was the indifference of foundries who thought quality control was was and obscene idea.
   The idea of high quality parts apparently came from Europe and England certainly brought it to the top of the line with their lock filers.I have had a "blast"copying some of their work.
Bob Roller

[Hudnut]

Finding a foundry that is prepared to deal with low numbers of castings and is prepared to work to achieve the desired quality at a reasonable price is a challenge.  There are different methods of removing the investment which can affect the surface.
When the castings were made for those trade gun locks, batches of 100 pieces were requested.  The foundry had a standing order for 30,000 pieces a month of one part for a single industrial customer.  There is a limit to how much time and effort they can put into a project that is insignificant compared with other orders.

[Jim Kibler]

Finding a foundry to make just a handful of pieces is difficult, but if you have any kind of production it's not a problem.  I've used three different foundries over time and they've done decent.  You really just have to understand the technology and what you are dealing with.  We could make fantastic locks just with castings and no CNC.  People like to throw around the word CNC and think it's the reason for better locks.  In some ways yes as it allows us to make quality locks faster, but it's not necessary.  As and example look at the great locks Bob Roller made. 

[Bob Roller]

Jim Kibler,
Thank YOU for the comment on my lock making skills.It gave proof to my comment about what I think of myself as the maker and my opinion of the buyer.Your own work stands out like a goose egg in a bucket of coal and keep it up.
Bob Roller

[silky]

Awesome. Thanks for the replies, guys.

I'll wrap the tumbler post with some tape, add material to the pan and frizzen (had to anyway to rebuild the original's worn out one).  I'm thinking the hook of the mainspring wear it engages the tumbler nose, and the back of the top jaw wear it fits into the post to slide up and down, too.

The foundry I have talked with has been good to work with so far. I have been very clear since the start that this is a small project and they haven't balked at it. Speaking of, and based on your experiences, are there any specific points I should ask them regarding the process they use to ensure these come out the best they can? An example is the investment removal process that Hudnut mentioned.

Thanks!

- Tom

[Hudnut]

Ask them how they remove the casting from the investment.  What options are there?

[Jim Kibler]

Don't be too picky if your just doing a few pieces.  They are really just doing you a favor.  There really isn't much you should have to specify.  Most foundries are pretty good.  Who are you using?  I might know them.

Jim