Book on Lock Geometry?

[Randall Steffy]

I would like to research the fine points of flint lock design, the geometry of an ideal or optimally performing lock. In particular I hope to find information on the relationship of cock/flint and frizzen/pan. By relationship I mean the way the flint strikes and bears against the frizzen as the action produces sparks, goodly amount without being unduly hard on the flint or the frizzen. Are there books that attempt to explain the geometry and factors that determine the excellent lock?

I ask this in the Builder's forum as I need to know this to assemble a lock where no pattern for the proven positioning of components and related considerations exists.

Thanks for your help.

[Acer Saccharum]

I made the tumbler for my jaeger lock. It was a study in timing, position, spring power, sear location, the cock stopping at the proper location on the plate. Whew, talk about a puzzle! Can only be done one step at a time, and in proper sequence.

I wish for such a treatise, too.

More pix at:
http://s12.photobucket.com/albums/a246/Tom45-70/Jaeger/?start=100

[Michael]

Randall,

If you can find a copy of volume #1 of the JHAT ( Journal of Historical Armsmaking Technology) it may be of some help. It is entirely about lock making and written by Gary Brumfield and should answer some of your questions.

Michael

[JoãoSoaresPB]

I made the tumbler for my jaeger lock. It was a study in timing, position, spring power, sear location, the cock stopping at the proper location on the plate. Whew, talk about a puzzle! Can only be done one step at a time, and in proper sequence.

I wish for such a treatise, too.

More pix at:
http://s12.photobucket.com/albums/a246/Tom45-70/Jaeger/?start=100

Hi, thank you so much, it will be very useful for me too.

[JoãoSoaresPB]

Randall,

If you can find a copy of volume #1 of the JHAT ( Journal of Historical Armsmaking Technology) it may be of some help. It is entirely about lock making and written by Gary Brumfield and should answer some of your questions.

Michael

Hello, Where can I find a copy?

Thank you.

[Randall Steffy]

Thanks for the suggestion, Michael. Amazon had several copies, and I have one on the way.

If there are other recommendations, please post them. I will be most grateful.

Yes, Acer, a treatise on this subject is overdue if none exist.

[FG1]

Track of the Wolf has a book by Pryor Mt. Bill Newton on locks ,I dont recall exact name of book.

[Joe Stein]

Track of the Wolf has a book by Pryor Mt. Bill Newton on locks ,I dont recall exact name of book.

The name of Pryor Mt. Bill's book is "Hand Forging - History - Patterns - Of The Muzzle Loading Gun Lock".
I picked up a copy at Dixon's during the Gunmakers' Fair.  I think I paid $15 for it in the shop.  i haven't read it all the way through, but it looks like it might be what you want.

-Joe

[dave5722]

I have a copy of Hand Forging the Muzzleloading Gun Lock by Pryor Mt. Bill Newton.  Good book, lots of hand drawings.

The book looks like it's from 1978.

Dave

[Rolf]

I just orderd volume #1 of the JHAT from amazon.
Where can I find a list showing what the other volumes are about?

Best regards

Rolfkt

[rich pierce]

It's best to do a good study of existing fine locks of similar size as far as the angles of the tumbler notches, how you time the cock by where you set the square hole, stops for the cock and bridle, and leverage for the tumbler nose.  Pryor Mountain Bill's book has general pattern sketches, but the detail is not fine.  JHAT 1 has a lot of proportions for locks that are helpful.  The specifics of timing of the notches, sear length, sear nose/arm ratio, etc are critical else you can end up with a mainspring protruding below the lockplate when fired, sear arm height not constant at half and full cock, a tendency for the sear to fall into the half cock notch, etc.  I'd make a working model from thin plexiglass or something before committing to steel.  I'm quite sure the old lockmakers used templates in copper or brass sheet for their locks.

[J.D.]

I browsed through Prior Mountain Bill's book at Dixons. I really didn't see all that much worth reading...or paying 15 bucks for.

I think Rich is right about studying good locks, in general, and specific locks of the size one wants to make, in particular.

Check out the photos of locks Jerry Huddleston has posted. There may be photos on is web site, and possibly in the archives of the old board.

Someone once mentioned JHAT V had good information on lock making. Unfortunately, I don't have JHAT Vol 5, so I can't speak to its content.

God bless

[Acer Saccharum]

Rich, I think your template idea is probably spot-on.

back in the day, the lockmakers in London were cranking these locks out, far cheaper than a smith could make one himself, even when you include the price of transport and the markups by the distributors and vendors. I imagine they had not only templates, but forging dies and filing jigs.

Templates, hmmm. Next time I do a lock, I will try this out.

Tom

[peterw]

Look here: http://www.feuerwaffen.ch/HTML/HTML%20Flintschloss%20Theorie%20mini/sld001.html

[Benedict]

Look here: http://www.feuerwaffen.ch/HTML/HTML%20Flintschloss%20Theorie%20mini/sld001.html

That looks cool but I don't read German or whatever it is.  Has it been translated?

Bruce

[flintriflesmith]

...
Someone once mentioned JHAT V had good information on lock making. Unfortunately, I don't have JHAT Vol 5, so I can't speak to its content.
God bless

Volume V has one article on forging of cocks out of wrought iron that I wrote. It does not have anything else on lock making or lock geometry. I'd say the article is of little use to most modern lock builders except for the background information on how the work was done in the period.

Volume V is also rare because it is the only volume that was never reprinted and it featured an article by Wallace Gusler and Dave Harvey on the construction and decorative details of the grand John Sheets rifle made in Staunton VA.

Gary

[Acer Saccharum]

Grab the pictures with dimensions, there are charts with numbers toward the rear of the slide show. Even if they are in metric, you shouldn't need a translation for that. 

[Benedict]

Thanks, Tom.  I guess I gave up too soon.

Bruce

[Randall Steffy]

peterw, thank-you for the link. That is the sort of information I was hoping to find and should prove interesting to study. As I compare examples I have in hand and plug data from this source into layouts, hopefully I will get a better understanding of what works and how it works.

Gary, thanks for the information on the specific content that JHAT 5 includes or does not include. Most considerate of you.

[flintriflesmith]

Rich, I think your template idea is probably spot-on.
back in the day, the lockmakers in London were cranking these locks out, far cheaper than a smith could make one himself, even when you include the price of transport and the markups by the distributors and vendors. I imagine they had not only templates, but forging dies and filing jigs.
Templates, hmmm. Next time I do a lock, I will try this out.
Tom

Tom,
You definately need a copy of Vol I of JHAT! I not only showed pictures of the sheet metal templetes, which were called patterns in the period, (page 23) but I also included a full scale image of some of the key parts of a 1770s style (5 & 3/4 inch plate) English lock (page 25) so you could trace it and make your own patterns for the plate, cock, and internals.

Gary

[J.D.]

You definately need a copy of Vol I of JHAT! I not only showed pictures of the sheet metal templetes, which were called patterns in the period, (page 23) but I also included a full scale image of some of the key parts of a 1770s style (5 & 3/4 inch plate) English lock (page 25) so you could trace it and make your own patterns for the plate, cock, and internals.

Gary

A similar pattern, with more detail is illustrated on the inside covers of McCrory's "The Modern Kentucky Rifle"

[Stophel]

There can be a lot of trial and error involved in lock making/building/modifying.

I have learned one thing: that the smaller the lock is, the harder it is to get it to work well...

I've also learned that if you just copy the dimensions of a Siler lock, you'll pretty well have it figured out!   

[FlintRock Rob]

peterw - thanks for that link. I clicked around and got to these:

http://www.feuerwaffen.ch/radschloss.htm
http://www.feuerwaffen.ch/HTML/HTML%20Radschloss-Nachbau/frame.html

wheellock details