General discussion > Gunmaking tools and techniques- metal shaping
forging an iron flintcock
Clint:
I realize that this info should go to tutorials but we are going to land it here for the time being, If the moderators preferr that it resides in tutorials, I can upload the pdf file to keep everything consistent.
Making the flint cock is a lot more interesting than the lock plate. In reading articles on the web, people seem to have trouble figuring out how to do it and I really don’t know how they did it in the 18th century. It would seem fairly obvious that the lower jaw could be split and bent out from the main body, so we will start there.
I am starting with a square bar 3/4 “ square and splitting into the end for about 7/8 “. The chisel is not sharp, but actually rounded on the end. This shape will easily open the piece of iron, while minimizing the risk of splitting (keep the iron HOT) The metal is held tightly in a sturdy vise and subsequent heats can be positioned in the same place several times. By using the same grip the metal will thin slightly at the grip point and form a little shoulder that will help to keep the piece from slipping down through the vise. Take as many heats as you need and use a smallish (3/4 lb) hammer.
The two halves are opened up, over the edge of the anvil and one is selected for the comb. This comb is squared up and reduced in thickness to about 3/8 “ thick. Be careful not to go too thin or you will be disappointed when the final shape is filed up.
A 1/4” - 5/16” fuller is used to thin the neck, just under the jaw. A top or a bottom fuller can be used.
We are now at a point where we need a couple of special tools. The parent iron is 3/4” square and we need a lower jaw that is an inch wide with file margins. Simple to flatten the jaw, but it is very difficult to ‘get in’ near the comb without banging things up.
The first tool I will show you is a kind of stake which stands up in the anvil’s hardy hole. This stake will support the bottom surface of the lower jaw while we apply hammer persuasion to the upper surface
The goal of this operation is to widen the jaw and to impart a rounded surface to the bottom.
The second tool that is helpful is a top tool that is used to set the shoulders, adjacent to the comb down and widen this area as well. The gap or slot in this tool is 7/16” wide and the face is a simple radius.
Neither of these two tools are truly mandatory, but my experience is that the flint cocks made without these little helpers usually come out too narrow and the extra effort is worth it.
The third tool is what I consider the key to forging a flint cock. The bottom jaw, more or less, forms itself and we can see the finished form evolving. The serpentine shape which is our goal is a little bit trickier. It might make sense that we could bend the shape or just use a fuller to get that lower bend. To bend a piece of iron that short in an exact spot is beyond me. I want to make these things at the rate of 5 or 6 an hour. If we use a fuller to dent the lower curve we will end up with a big flat spot on the front or ‘chest’ of the piece. The solution seemed to be to hammer the lower bend into a swage so I imagined what kind of swage would work.
This swage fits into the hardy hole and performs like any other swage. I made it to fit the contours of a finished flint cock so that when the body of the piece is flattened out it would expand and accommodate many sizes and styles of locks. This particular tool was made by upsetting a piece of steel and hammer shaping followed by grinder and file finishing. An easier method, that I used earlier was to bend a piece of steel to the shape of the flint cock and arch welding it to a stem that will fit in your anvil or in a vice
So we have the jaw opened and the neck drawn down. Next will be to cut the piece off the bar. Lay the piece over the cock swage and mark it with soap stone.
Using the lock drawing as a guide, mark the swage with a soap stone target so you can aim the punch into the right spot.
Using the same small diameter punch we used to split the jaw, carefully begin to set the reverse bend into the swage.
As the piece begins to fit, there may be a small lump gathering at the bottom of the flint cock. You can encourage the fit by hammering this lump diagonally into the swage, and some of it will need to be trimmed of, using a grinder while the piece is still hot.
The body of the flint cock is still very thick and we can hand hammer to a rough thickness directly on the anvil face. This will close up the punch mark we just made but the bend will remain. The ‘chin’ will be angled back and the neck open. Leave this in place for now, as it will make initial filing easier.
The top set can be used in conjunction with the stake or the main swage to neaten up the shoulders
After flattening the body down to about 3/8” thick the piece is cooled and the area under the jaw is cleaned up with a round file. It is then reheated and bent to conform with the shape of the sheet metal pattern. At this point, the forging should be larger in all dimensions and we can begin filing.
I have photographed the filing process and need to edit the pics and write the text so stay tuned.
Clint
LynnC:
Thanks for your efforts. Im interested. Ive tried making the cock but without the dies/tools. I can see their value. Looking forward to more.
Daryl:
WOW - that's cool!
Greg Pennell:
Another awesome post, Clint! Thanks again for sharing your methods...I may never actually forge a lock, but it’s very interesting to see the process.
Greg
Elnathan:
I'd like the pdf file available, as I can't print out a thread on this forum without losing the pictures (the printer-friendly version substitutes file names/links for the actual pictures).
I've been looking forward to this part of the lock-making process. Like most folks here, the chances of me ever making a whole flintlock from scratch are low, but I am very interested in customizing and modifying the externals of production locks. In particular, I have a Chamber's Gunmaker's lock with Golden Age parts on which I want to replace the cock assembly and possibly the frizzen spring, and it looks like I will need to make a replacement cock from scratch if I want to match the throw and angle of the one that comes on it. So this tutorial is of more than academic interest even for those that may never make a whole lock.
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