left-handed Alex Henry/Stanton/Bob Roller lock. Part3. The tumbler

[Rolf]

The tumbler
The tumbler starts as 36mm long piece of 40mm axle rod.


The first step is to turn and thread the hammer axel. It’s threaded for a M4 screw. The diameter of the axle is 6,5mm. The blank is then reversed, jaws clamped on the hammer axle as far it will go in the chuck with the disc touching the top of all three jaws. This keeps the blank level. The bridle axle turned down to 4mm. If you try to turn the bridle axle first, it is prone to twist off while turning the larger hammer axle. Remember to leave a small, raised ring around the base of both axles. This reduces the friction between the tumbler and the lock plate + bridle.


You now have disc with two axels. Turn down the disc so it fits on the lock plate, keep it as large as possible. This decides the length of the tumbler arm.


Take a thick piece of mild steel, drill a hole for the bridle axel and soft solder the tumbler blank on it.
Mill the hammer axel square 5, 3mm.The broached square hole in the hammer is 5,2mm.  This leaves the axel it a hair larger.
 

File a short draft at the end of the square axel and swag the hammer on to it. To the rigth in this picture, you see the hollow brass punch I use to swage the hammer all the way down. This gives a perfect fit.


 File off the excess square axel. Remove the hammer by tapping out with a punch.


Heat and remove the tumbler blank. Clean off the solder.


In this picture, the tumbler blank is painted with dyke and mounted on the lock plate. Notice that the blank covers the hole drilled for the sear axle. The washer mounted on the bridle axel shows what has removed to make room for the sear. Scribe around the washer.


Mount the bridle on top of the tumbler blank using an extra-long screw in the last bridle post. Place the hammer in half cock position and scribe around the posts.


Drill out as much of the waste material as possible. Remember to drill the post holes under sized.


Saw off as much of the waste as you dare, leaving ample material for the tumbler arm.


Carefully file the “post holes” in the tumbler until the bridle slips down over the tumbler blank in half cock position. Clean up the sawn outlines


File carefully at the areas pointed to with red arrows on the tumbler until the hammer can be rotated to the fired position. In this position about 1mm away from touching the bolster and further rotation stopped by the second bridle post hitting the tumbler.

 
File carefully at the areas pointed to with green arrows on the tumbler until the hammer can be rotated to the full cocked position. Further rotation is stopped by the tumbler arm hitting the first bridle post.

 
The tumbler arm is going to be connected to the main spring by a stirrup. The stirrup axel hole is 2,5mm and located just below the bolster with the hammer in the fired position. The “nose” of the tumbler arm is a 6mm circle and the axel hole is in the center.  Punch the location of this hole on the tumbler.


Drill the hole. Do not move the blank. Put a piece of 6mm round stock in the chuck and trace around.


File the nose so it’s a half circle. Next adjust the cocked position of the hammer so the nose is 2mm below the upper edge of lock plate. This done by filing the tumbler arm where the first post hits it.


Saw out the tumbler arm. Keep bottom of the arm a straight line. This will make it easier to slot the arm for the stirrup later. Leave enough of the disc so the sear can rest on it when the hammer is fired.


There is still a bit to do before the tumbler is finished. The notches for the sear has to be cut, the fly installed, and the arm slotted for the stirrup. This must wait until these parts are made.

 Also, there is the question where the screw for the sear spring should go. If it is placed between bridle post two and three, the tumbler must be adjusted to make room for it.  It might be better to place behind bridle post three if there is room enough. Suggestions?

 Best regards
Rolf

Links
left-handed Alex Henry/Staton/Bob Roller lock. Part 1. Lock plate and Hammer
https://americanlongrifles.org/forum/index.php?topic=73225.0

left-handed Alex Henry/Staton/Bob Roller lock.Part2. Four post bridle and screws
https://americanlongrifles.org/forum/index.php?topic=73497.0

[Bob Roller]

Make a threaded plug with the large diameter the same as the post.This will locate the sear spring and should be done after the
finished sear is in place.With the sear in place the half and full cock positions can be located and the cut and shaped to accomodate the sear.
Your are doing well on this project.I have a smaller 4 screw that's been laying in a semi finished condition for about 5 years.
Good luck and don't be in a hurry.
Bob Roller

[Curtis]

WOW Rolf!  A great deal of work there but the resultant finished product was worth all the effort!!  Absolutely fantastic.



Curtis

[Bob Roller]

WOW Rolf!  A great deal of work there but the resultant finished product was worth all the effort!!  Absolutely fantastic.



Curtis

A LOT of work for sure.years ago Bill Roberts and I talked about the quality in these types of locks and agreed they were and still are the zenith in such mechanisms.Bill asked me if I had ever made a "3 pin" version and I said yes.Other than the missing 4th "pin"there was and is NO difference in the smoothness or performance and both are good looking if attention is paid to small details.The last Hawken style lock I made had a "3 pin" bridle and zero over travel.The man that owns it thinks it's a good idea as well. Shortly after I joined this forum in 2011 I made 14 flintlocks using the Davis Twigg external parts and the "3 pin" mechanism.10 were planned and I bought the parts and the last 4 were made on parts furnished by the customers.An immediate difference is noticed when the lock is cycled from the top of the plate to fully cocked.I did get criticism from a few for upgrading a lock that was shaky in design from day one.
My congratulations to Rolf and the sear spring does go under that third screw and the fourth screw furnishes the rigidity that makes these locks so good.
Bob Roller

[jgraham1]

Just amazed at the talent to produce this.  Great job for sure.

Jerry

[Flint62Smoothie]

YOWZA … know I really know WHY I must purchase my own, LOL!

Outstanding work and tutorial!

[Dave B]

Awesome Job Rolf, I found a picture of a comperable lock that shows the position of the sear spring. These are incredible locks. Thanks for showing the process. I look forward to seeing your final product.

[smylee grouch]

What a great run down on this project and a great looking lock. Thanks for all the work of documenting your work.

[Bob Roller]

Awesome Job Rolf, I found a picture of a comperable lock that shows the position of the sear spring. These are incredible locks. Thanks for showing the process. I look forward to seeing your final product.

A quality that is almost extinct and was never a part of American gun making back in the "day". I made my first one in 1987 and sold about
35 of this style before I stopped lock making in 2019.About 8 of a smaller scale version was made and have been posted here.
Do you know who made this one? I am thinking maybe Jim Westerberg.
Bob Roller
I just remembered a number of Schuetzen locks with the "3 pin"version of this bridle going to Germany for target rifles.

[hawkeye]

Nice to that tere are craftsman who are able to make such a fine lock. TOP

[Bob Roller]

Nice to that tere are craftsman who are able to make such a fine lock. TOP

Hawkeye,
In 2008 I was making a nice boys rifle for my the 8 year old grandson.I had the barrel in a nice piece of English walnut.
I was planning a scaled down Creedmoor style rifle.I had a scaled down "4 pin"lock started. My shop was robbed and entry gained by pushing the air conditioner out of the wall.The gun was taken along with some small tools.I know who did this but had no proof.
Until today,that started lock lay on my bench and today I decided to finish it and probably offer it for sale here on this forum.
I am over 3 years out of practice in lock making but it's off to a good start.It's small,4 and 3/8 x 1" and only the hammer is a casting.
Next are the two positions on the tumbler,the link and fly plus finishing the sear AND the two springs.The hammer is a fancy one and
I will detail it a bit and checker it.No big rush or stress to get it done either.
Bob Roller 

[Dave B]

 Bob, I dont know who the maker of the lock was but I knew that I had to have the picture for referrence in the advent of taking up the challenge of building one. They are a marvle. No rush on finishing that lock for me.... I would use it for building my grandsons rifle. He hasnt been born yet but will be here this coming January and I know its going to take me a while to get all the bits together for the build. 

[Rolf]

Thank you all for your kind comments and tips. At the moment I'm working on the sear and sear spring. Hope to post that part before xmas. The flu/covid season has started in Norway, which has caused a lot of overtime at the OR. Been hard to find spare time for this project.

Best regards
Rolf

[Jim Kibler]

Rolf,

Some really nice work for sure!  Bet the lock is going to be super slick and crisp... 

Something to consider trying...  Ditch the string of drilled holes and just hacksaw and file the perimeter of parts.  I think you might find it easier.

Great job!

Jim

[Rolf]

Rolf,
Something to consider trying...  Ditch the string of drilled holes and just hacksaw and file the perimeter of parts.  I think you might find it easier.

Great job!

Jim

A hacksaw works great for straight cuts in steel up to 1/8 ".  On thicker steel or parts with curves, it is too easy to mess up the parts profile by slightly canting the blade. Also, when cutting steel that's more than 1/4 " thick, drilling holes saves a lot of elbow grease. A metal bandsaw as you suggested earlier would be a big help, but so far, I've only found large industrial models in Norway that cost an arm and a leg.

Best regards
Rolf

[Bob Roller]

The closely spaced holes are an alternative but when I got a milling machine I developed an idea of making a coordinated cut using it and the tumbler is held in a collet and then a fast finish using a bench grinder and a white wheel and checking is done with a circular gauge that is an approptiate size for the job.A 5 or 7 flute carbide end mill is used.Slotting for the link is done with a 1/2 inch woodruff key cutter that was .094 thick and now .075.The mill is also used in tapering he mainspring and shaping the sear.Filing is also involved.and the fancy bridle is an example of it and a variety of them is involved.
   I DO admire your tenacity in the making of this lock and your posting of all the steps involved are astounding.The scaled down version I have on the bench now is sold if and when it's done.Both springs,sear and fly must be made and the link is left over from long ago work.
Keep the pictures coming.
Bob Roller

[D. Taylor Sapergia]

Just for reference purposes, I include a photo of the lock from my Joseph Lang 16 bore rifle.  It has a three screw bridle and a sliding safety.  The Roller lock in my Hawken rifle is every bit its equal.

[Bob Roller]

Taylor,
Thank you for the comment on my lock being equal to this one.The last Hawken lock I made was like this one only minus the sliding safety
and there is NO difference in the smoothness either between this "3 pin" and the "4 pin" versions. I think you have one of my small "4 pin"locks
and it was #7 I think.The 30+month time lag and my eyes not being what they once were makes me doubt my sanity for finishing this little
lock.A long ago friend used to say "One last go around before he looked in the mirror and it broke". ;
Bob Roller

[Bob Roller]

Taylor,
Thank you for the comment on my lock being equal to this one.The last Hawken lock I made was like this one only minus the sliding safety
and there is NO difference in the smoothness either between this "3 pin" and the "4 pin" versions. I think you have one of my small "4 pin"locks
and it was #7 I think.The 30+month time lag and my eyes not being what they once were makes me doubt my sanity for finishing this little
lock.A long ago friend used to say "One last go around before he looked in the mirror and it broke". ;
Bob Roller

I almost forgot,I did make 14 flintlocks on the Davis Twigg externals and even more schuetzen rifle locks for a shop in Germany and used this mechanism on all of them.Their term for this bribde is "Der Kreuzstudel".