Building a lock from a casting

[Jeff64]

Some questions regarding building locks from castings such as The Rifle Shoppe. 
Tools. Are a milling machine and a lathe a necessity or a nice to have/time saver?  Is just a drill press sufficient?
Classes.  Anyone do a class on how to build a lock from a casting or would anyone be interested?  How many days would this take assuming you might not actually complete the lock, but just go far enough through each step to understand the process.
Tutorial. I have seen this tutorial http://www.ctmuzzleloaders.com/ctml_experiments/mantonlock/mantonlock.html which looks pretty thorough (and does use a lathe).  Probably could build from this, with exception of lathe part, a big investment for something I might not do a whole lot.  Wonder if this process could be farmed out?  Anyone provide this type of service?

R/Jeff

[Bob Roller]

I have used 2 sets of TRS castings but ONLY the external parts and they stretched the
limits of my experience as a lock maker to the limit.These were left and right flint locks
and I THINK Mantons but I am now not sure.I do remember it took 9 months to get them
which was not good either.Using antiques as a master pattern is not the best idea.
Frequently these parts are  to small to begin with and the shrink factor reduces them too
much.IF you are wanting to do this as a "To see if I can" project,enjoy the ride and you
WILL learn a lot from it.
Bob Roller

[conquerordie]

Nice tools make jobs easier, that being said i built maybe 4 TRS locks and never had anything more than a drill press, files, polishing stones, and a heat treat oven for frizzen and springs. Its a learning experience for sure.  Youll mess up, curse like crazy, give up, and then come back and finish it.  I did that for all four my locks.  Of course i dont build anymore, so i guess my last one broke me!

[jerrywh]

Bob Roller is exactly right.  I have built at least 8 locks from second generation castings and my opinion is that there are very few gun makers today who either have the expertise or the tools to do the job. However some of the sets sold today have been engineered to fit pretty well. I have never built a rifle lock set but Ron Scott has done some I know for sure. I would think a chambers set would be easy compared to some I have done. Most of mine were French or English which I had cast or forged. A tig welder helps a lot.

[Jim Kibler]

I've made castings from originals and there are problems that few address.  Machine stock should be added in all the critical areas.  Also very thin areas ought to be built up if necessary.  The best way is to make a scan, scale it up, wrap it with a thin layer of material (.003-.005"), 3d print it, fix any problem areas by building these up and then making molds.  This seems like a lot, but it's actually pretty easy.  Putting the scanning and printing aside you can just build up the necessary areas on the originals before casting a mold from them.  Few even do this, but to make a good quality reproduction I feel it's a must.  Finally you also have to consider the quality of the original work.  There are often considerable issues found on original parts.  These should be addressed prior to making wax molds from them.

Jim

[Bob Roller]

I made a lot of flint locks from the Chet Shoults* parts after he lost control of the moulds.
Also a round tail Twigg.The Ketlands I made were from good moulds from an unknown
source.No internal parts were available but that was not a problem.
I have also had good results from the L&R external parts of the Late English,Durs Egg and
Small Manton.The last two I made were Durs Egg last August and the last Hawken caplock
was almost a years ago.Now it's triggers only for the foreseeable future.
The Shoults and the Twigg and Ketland I started making in 1962.The Twigg frizzen mould
was changed and the foot of the frizzen where the screw went thru was reduced to a way
too small size and I dropped it.
The 2 sets of parts from TRS were for a man in Tn.and I want nothing else like that to do.

Bob Roller
* There were internal parts for the Shoults locks but I never used them and made my own
for as long as I made them.

[T*O*F]

If you just want to get your feet wet, there are older NOS lock kits floating around of Siler and L&R locks.  They require no special tools other than your drill press and some files to complete.  They come with instructions.  I thought I had a couple but I must have sold them.  I'm sure there are guys here with one in their drawer somewhere.  Chambers might still sell the Siler kits.

[Clint]

When a lock is scratch built, the pieces are usually slightly oversize and the metal around various holes can be brought in with a file to get concentricity. With castings from an original the opposite condition exists, the metal around the holes is already gone. A milling machine is not required, but a good drill press is mandatory. A cross feed is very handy and center drills are very important especially small ( 1/4 ") sizes. You can often sight a tumbler chucked in the drill press to see how true it is, If it is out and you don't have a lathe, take it to a machinist. Drill undersize and check check check for squareness. If you flub one of the pieces, you still have a good model so make a new one out of mild steel. Now you are swinging off into the lock making world...

[davec2]

The following is a partial repeat of a post I did five years ago.  I have built three or four locks from a set of castings (three English Dragoon pistol locks and a Ferguson rifle lock) purchased from TRS and Blackly.  It is not an easy task and, as others have noted, the exercise is a great learning experience (and Jerry H is spot on when he says it helps to have a TIG welder !)  All four locks had issues that needed a fair amount of effort to correct or compensate for.  Not quite as difficult as learning to forge all the parts of a lock, but one step harder than buying a set of parts, is to try to get your own castings made and then assemble a lock.  When I was young (and stupid).....and before there was the opportunity to buy excellent fully assembled locks from Jim Chambers and Jim Kibler.....this was the long and laborious path I followed to get away from the $12 Spanish made lock I started with.......


In 1969 I was a sophomore in high school.  I had a Dixie catalog with a 2" x 3" very grainy black and white photo of a flintlock rifle.  You can imagine how much detail there was.  At the time, this was the best lock I could afford to purchase from Dixie.......



I built one rifle with one of these and it worked OK, but I innately knew it that the architecture of the rifle looked more like a canoe paddle than a rifle...and I knew the lock was junk.  I determined to build a better lock (from looking at a bigger picture (3 x 3") in the Dixie catalog.  Over a few weeks, I carved a set of master parts and cast them in silver, brass, and copper...anything that was easy to cast and work.  When I had all the parts working together on a wooden mock up lock plate, I vulcanized a set of rubber molds and pumped waxes of all the parts except the springs.....







I found a local foundry that did steel castings.  The guy who owned the company got a kick out of a young kid trying to build flintlocks and he said he would cast as many wax patterns for me as I wanted to make up for $25.  I didn't have $25 but told him I could borrow it and he held out his hand and said "Deal !"  I made up 20 sets of wax parts and brought them back to him and he cast them all for me in a few days.  However, when I went to pick them up, he was holding a box and he said that the castings didn't come out as good as they should have, so I could have this batch for nothing.  When I opened the box, the parts all looked fantastic to me.  When I looked back up at him, he just winked at me.  I eventually had him do some additional castings for me and insisted that he let me pay for the next batch, which he did.



I started putting the pieces together and making a real lock plate out of a steel strap......



Finally got the lock all together, made the springs from spring stock (also from Dixie) and hardened all of it.....and then, since I couldn't engrave, I covered the plate with asphaltum varnish, free hand scribed the decoration I wanted, etched the pattern with dilute nitric acid, and then gold plated the etched lines  before I removed the asphaltum mask.



I built two locks and then made a matched set of rifles for my Dad and I.  The barrels were Douglas, 13/16 inch straight, .45 caliber.  Not great locks, not good architecture on the rifles, (but much better than the first rifle with the Spanish lock.)  I still have the pair of rifles and they mean a great deal to me for the all the lessons I learned building them at the tender age of 16.

[Daryl]

Davec2 - thank you for the wonderful story.  You are in inspiration - such talent WOW!
 No wonder your work is so beautifully executed.

[Bob Roller]

Some questions regarding building locks from castings such as The Rifle Shoppe. 
Tools. Are a milling machine and a lathe a necessity or a nice to have/time saver?  Is just a drill press sufficient?
Classes.  Anyone do a class on how to build a lock from a casting or would anyone be interested?  How many days would this take assuming you might not actually complete the lock, but just go far enough through each step to understand the process.
Tutorial. I have seen this tutorial http://www.ctmuzzleloaders.com/ctml_experiments/mantonlock/mantonlock.html which looks pretty thorough (and does use a lathe).  Probably could build from this, with exception of lathe part, a big investment for something I might not do a whole lot.  Wonder if this process could be farmed out?  Anyone provide this type of service?

R/Jeff

I could not have done half of what I did without a lathe and I have 4 of them. The vertical mill is indispensable
as is the heavy drill press and two bandsaws for metal cutting,one vertical and one horizontal.I skimmed the
tutorial on the fancy Manton locks and would NOT recommend a 4x40 thread into a blind hole as was used in
a Manton style frizzen spring. I would use a 4x48 so as to ease the stress on the tap. Break one off in a small
blind hole and then the moaning and groaning begins.One advantage for me was that I made my own screws
and still do on the double set triggers I am now offering.Keeping spring steel to actually make these springs
is a good idea.I have always made my own sear and main springs and used cast ones for the frizzen springs.
These springs take a beating when the frizzen slams into them but they do not have to go thru a partial rotation
like a mainspring does. Sear spring a fussy little thing that requires close attention during shaping and installation.
Recently I have started used 5 and 7 fluted end mills and found a company in Chicago that had good quality,
made in the USA Carbide and the price is reasonable if you have need for such tools.The company is Maritool
and they have a website and phone# !-800-352-7773.They have been beneficial in trigger making for me.
I don't think I'll make any more locks and now work part time on the triggers.Today,no work because my wife
had to get X rays made for a troublesome knee.It gave way recently and she just barely missed a very bad
head injury on our front porch. She was coming UP the steps when it occured.

Bob Roller

[Jim Kibler]

Yes Bob, Maritool.  We use them for tool holders and some tooling.  They make quality products at a fair price.

Another is Lakeshore Carbide.  We buy a lot from them.  http://www.lakeshorecarbide.com/

Jim

[smart dog]

Hi Jeff,
I built quite a few locks from TRS and Blackley parts. The process ranges from pretty easy and straight forward to requiring a lot of welding.  The bigger musket and fowler locks are usually pretty good and have plenty of metal to work with.  Small pistol and fowler locks are much more difficult because you don't have much to work with and by the time you clean up the castings you've removed too much metal.  TRS parts should be heat soaked at 800-900 degrees for an hour and cooled slowly before starting work because the surface can be pretty hard and ruin your files. No need to do that with Blackley's.  On most of the locks I've built, the lock plates were warped and needed to be straightened before fitting any parts.  Do not trust any of the witness marks on the lock plates. On the TRS early pattern Bess lock I am building now, the only mark I could trust was the one for the sear because engraving on the plate clearly showed where it was on the original. All of the other marks were off.  A welder (mine is gas) and heat treating oven are extremely useful. I do not have a milling machine but use a drill press with XY table and vise, belt sander, files, and polishing stones. I substitute skill for the milling machine just as they did in the 18th century. 

dave   

[David Rase]

I have bought quit a few tools for my lathe and mill from Shars.  They have worked well in my non production shop environment and are reasonably priced.
David
 

[Realwarrior]

I tried to build a lock ONCE.... Gave up and ordered the lock. Although it would have been nice to know exactly how to build it, my time is worth something. Now if I could learn to cast and build, that would be worthy of my time. To those of you that scratch build locks, you definitely have my admiration!

[Jeff64]

All,

Many thanks for the comments.  After reading everyone's comments I came to a few conclusions.  1.  It can be done.  2.  Better to start on a big lock as you'll have more to work with.  3. Heat oven and TIG welder key, a is lathe important, but you can get by without one.  I've got a TRS Continental Trade Lock lined up for my first try.  A BIG lock, almost 7" lock plate and no bridle.  That gets me past 1 and 2.  Been looking on Ebay for a used lathe, thinking about the old unimats, which also has a milling capability.  It's not a big lathe, but should suffice for a lock.  I know some may say it's not the most accurate, but I have to believe it's better than existed 200 years ago. Two things still have me puzzled.  Many comments about lock parts coming out of the mold slightly smaller than the original.  Makes sense, but wouldn't that shrinkage be uniform?  Seems to me that if everything was slightly smaller, but to the same degree, there shouldn't be that much of an issue.  Other thing is the TIG welder.  What's that for?  To add metal? Where is that usually needed?
Many thanks, appreciate everyone taking the time to share their experiences.

[Bill Raby]

Shrinkage. Lock plate gets 1% smaller. So does the tumbler and the sear. Not a problem. The hole for the tumbler and the whole for the sear screw get 1% closer together. Still not a problem. Then you do the finish work on the parts. Tumbler and the sear both get another 2% smaller. But the holes in the lock plate do not get any closer together. Now you have a problem. TRS has been selling finished lock made from their casting for a while so obviously it can be done. They have been doing it for a while and have a lot of practice at it. Probably took them a while to figure it out. It certainly can be done, but don't expect it to be easy.

[smart dog]

Hi,
The biggest problem is not shrinkage.  It is the quality and precision of the castings. As I wrote previously, on some, particularly smaller parts, by the time you clean them up and true edges and surfaces, there may not be much metal left to surround important holes or fit properly.  The welder is very useful for adding metal and reinforcing where needed, filling casting voids that show up, and heat bending parts. I'll give you a current example.  I am building an early Brown Bess musket using TRS castings for a pattern 1742 lock.  It is a big lock.  When I cut the sprue off attached to the lock plate bolster  forward of the pan, I uncovered a hole in the bolster almost 1/8" deep.  It was a casting void and was right where the frizzen screw would be located.  I filled the hole with weld.  Next, for whatever reason the vertical width of the bolster at the frizzen screw was not sufficient to drill for a 10-32 screw that was lined up properly with the pan and pan bridle. When compared to photos of original locks, you can easily see that the bolster is too thin.  I have no idea why that is because it not shrinkage or a casting flaw. It is a product of the mold used.  Anyway, a proper sized screw would have been threaded into paper thin metal surrounding the bottom of the screw.  Out comes the welder and metal is added to build up a proper bolster comparable with the originals.  The big lock plate was warped slightly.  I heated a portion red hot with my welder and tapped it into line.  When cooled, I used a big coarse single cut lathe file to file the inner surface of the plate true.  Then a finer file and then large rectangular stones and oil until the surface was flat and smooth ready to fit parts accurately.  On a lock without an internal bridle, the tumbler fit in its hole and against the lock plate is crucial. You will want to true the side of the tumbler against the plate and the tumbler post. Then flatten and true the inside of the plate. Under size the tumbler hole in the plate and either ream a precise tumbler fit or lap it with oil and abrasive powder. It must be a precise fit because the tumbler has no support from a bridle. 

dave   

[Bob Roller]

Lock parts CAN be cast so precise that all that is needed is to drill the holes,thread
and install them. Modern arms makers use extreme precision and a gun can be
assembled from the as cast parts and fired. I think Ruger does this and T/C had
that capability as well and I would assume it's the norm with the modern gun makers.
Muzzle loaders are a different breed of cat and the low,nearly non existent market
for one of a kind parts can't support the level of precision tooling needed.I think
the Kiblers are on the right track with CNC capability and turning out fine work
that most of us can afford. I am glad to see it.For a number of years my flintlock
making was based on three L&R models and the Chambers late Ketland and before
these I used the externals from the Shoults lock and a Ketland with a double throated
cock.IMHO the lock IS the internal parts and they must be up to a high standard
if any satisfaction is to be had with the gun.The Brits took that idea to superb extremes
with some of their locks and I have had fun trying to copy the Stanton 3 and 4 screw
styles.The last 3 screw style was installed in a Hawken plate and that was a year ago.

Bob Roller

[Jim Kibler]

Machining parts can be difficult and costly, but the results are worthwhile in my opinion.  With machining, you are not pushing the technology to the limits for it to work well.  This gives some breating room, which is not the case with investment casting. Casting can work, but certainly not as well as would be preferable for parts which interact with each other.  A lot of this comes down to how easily you're satisfied as well. 

There's a big difference between parts made from hard tooling (aluminum, epoxy) with dedicated masters versus parts made from silicone molds pulled from original parts.  Proper aesthetic design can be a benefit from working with original parts, but as has been mentioned, assembling them into a proper functioning lock can be very difficult and frustrating.

Jim

[Jeff64]

Jim,

I understand perfectly and would be hard pressed to disagree, but the reality is if you add the business decision in the mix (something which you no doubt are far more versed than I) the number of commercially produced locks is and will probably remain small.  Locks for American longrifles, jaegers and British fowlers/export locks are probably the extent of what will be machined in the next 10 years.  Looking at your current offerings shows me they will be near flawless in appearance and function.  Unfortunately I don't see a 17th Century Dutch trade lock high up on anyone's list.  Yes, the standard of acceptance for appearance, to some extent, and function, undoubtedly, will be lower. 
I guess the next great leap is when you can just throw a part in a "device", it's scanned for all measurements and then automatically uploaded into the CNC machine and reproduced.  I can hear the Luddites howling just thinking about that one.
Interesting thoughts, Cheers.

[smart dog]

Hi Jeff,
I agree with you completely. I will use Kibler, Laubach, or Chambers locks whenever they fit my objectives.  However, my diversity of interest in building different styles and periods means I'm going to be building locks from Blackley and TRS parts.  So we learn how to build good locks from castings, warts and all.  Fortunately, I don't have to make a full-time living from making guns and building locks.  I could never recoup the time and cost I put in making a parts set into a lock that meets my standards.

dave

[Long John]

Jeff,

I am late to this party but here are my thoughts on the matter.

I used the TRS #603 locks for my doublegun.  By the time I had both locks working as they should I had had to by additional parts for both from TRS because each lock has a part that had "issues".  For my next doublegun I have bought two locks for each lock I need.  If Chambers made the Small Siler in a left-hand version I would have used those.  If you are able to get or modify a Chambers lock that is "right" for your project then you only need to buy one.  I have found that I can modify the Chambers Golden Age Lock to make a wide variety of locks with distinctive shapes that are right for the gun I am building.  The vertical grooves behind the cock are always a problem if you are building something other than a gun with a German lock on it.  But where there is a will there is a way.

For the Chambers lock kits I have done all I had was a bench-top drill press.  Otherwise it was strictly hand tools and a good vise.  I was able to get the locks assembled and they have all worked fine for many years.  For the TRS locks I found my runty-little bench-top lathe a tremendous asset.

The Chambers locks I have made were large enough that they could be used without case-hardening the cock, top jaw and lock-plate.  I did it anyway and was able to case-harden in my back yard without difficulty.  Maybe I was just plain lucky.   The TRS locks are much smaller and MUST be case-hardened.  I will send the cocks, top jaws and lock plates out to a  professional heat-treater rather than try myself.

The cast in engraving on the TRS locks is the biggest negative to using their product.  I would prefer the parts be un-engraved.  Filing the parts down is not an option as that makes the parts too thin for reliable service.  It is a real challenge to clean-up the cast-in engraving.

That's all I know.  Good luck.

JMC

[Bob Roller]

Machining parts can be difficult and costly, but the results are worthwhile in my opinion.  With machining, you are not pushing the technology to the limits for it to work well.  This gives some breating room, which is not the case with investment casting. Casting can work, but certainly not as well as would be preferable for parts which interact with each other.  A lot of this comes down to how easily you're satisfied as well. 

There's a big difference between parts made from hard tooling (aluminum, epoxy) with dedicated masters versus parts made from silicone molds pulled from original parts.  Proper aesthetic design can be a benefit from working with original parts, but as has been mentioned, assembling them into a proper functioning lock can be very difficult and frustrating.

Jim

The Shoults lock were made from castings produced by waxes injected into some very fine
milled and polished cavity moulds.The whole lock,all but the screws were castings.
The biggest problem was foundries that had no real interest in anything but getting the job
done and out the door.This created all sorts of problems such as glass hard lock plates that
shattered like glass when someone tried to straighten them and glass hard frizzens that
even carbide couldn't drill a hole thru.Quality control was a big problem in the late 60's and
into the 70's as well.THAT plus a "market" that thought anything for a muzzle loader had to be
cheaper than dirt. That bunch finally faded away and I say Good Riddence and the appeal is
now to a more affluent market.
Bob Roller

[wvcruffler]

All,

Many thanks for the comments.  After reading everyone's comments I came to a few conclusions.  1.  It can be done.  2.  Better to start on a big lock as you'll have more to work with.  3. Heat oven and TIG welder key, a is lathe important, but you can get by without one.  I've got a TRS Continental Trade Lock lined up for my first try.  A BIG lock, almost 7" lock plate and no bridle.  That gets me past 1 and 2.  Been looking on Ebay for a used lathe, thinking about the old unimats, which also has a milling capability.  It's not a big lathe, but should suffice for a lock.  I know some may say it's not the most accurate, but I have to believe it's better than existed 200 years ago. Two things still have me puzzled.  Many comments about lock parts coming out of the mold slightly smaller than the original.  Makes sense, but wouldn't that shrinkage be uniform?  Seems to me that if everything was slightly smaller, but to the same degree, there shouldn't be that much of an issue.  Other thing is the TIG welder.  What's that for?  To add metal? Where is that usually needed?
Many thanks, appreciate everyone taking the time to share their experiences.


Was curious if you ordered a lock and tried it? I'm going to just to have the expeirence of learning how a lock goes together - not necessarily to even use on a rilfe. I think it will be worth what I have in it.

Phil C