cap making dies

[wicket]

Correct, Rojelio. The punch that forms the cross-shaped blank is made up of four pieces of steel rod held together tightly in a bundle by a steel cylinder at the top. The small channel remaining where the four rods touch has been bored out to accept the plunger rod that actually forms the cap. A bail mounted on the arbor press swings down to press the cross blank punching die, and then swings up again to allow the press itself to push the cap forming punch down through the center of the cross punch, pressing the cross-shaped blank to form it into a cup. Then the bail is swung down again to catch the cylinder which holds the four rods of the cross punch together, allowing the whole plunger assembly to be lifted free of the die assembly to allow advancing the copper strip in preparation to form the next cap. I used the cross forming punch to make the die with which it operates. A single hole the diameter of one of the punch rods was drilled straight through the two steel blanks that form the die that cuts the cross shaped blanks. A single rod from the cross punch bundle was pushed down through the hole drilled in the steel blanks, and a second rod was removed from the bundle, with the space remaining used to guide a drill bit to bore a second hole. The bit was removed, the rod was replaced, and another rod removed to allow a third hole to be bored, followed by a fourth. All four rods were set into their respective holes, and then the hole for the cap forming plunger was bored down through the bundle of rods and steel blanks to form the die that cuts the crosses, and on through the 1/2 inch steel blank to begin making the die that forms the actual percussion caps.

[Rojelio]

Wow! that took some thinking. I went a simpler route and just copied a tap o cap. It works ok with .005" material. Anything thicker and it punches through. I'm not happy with the aluminum. I need to get some copper foil and try that. I like the way your caps are formed better than mine. And I need to use thicker material.

Here's my cap making tools.

[wicket]

I liked the idea of aluminum from cans, but the caps i formed with my dies were just too brittle, the aluminum is quite hard and i don't know how to anneal it. I make my copper from scrap roofing copper using a small jeweler's rolling mill i traded for years ago, but you can buy copper online. I use heavier copper, 10 mil, and let the die thin it out a bit as the cap is formed. My die took some fine tuning to get the caps just right. The trick i worked out was to take a prick punch, and punch evenly around the edge of the bottom hole of the cap die. It makes the die tighter by small increments, which stretches the copper more. I found that the cap die had to be well polished, and funnel-shaped, even soft copper will punch out if the copper changes shape too suddenly or drags too much as it passes through the die. I'm pretty sure your die would work fine with copper if the plunger was a bit tighter so that it compressed the pleats a bit, using thicker copper might accomplish that.

[n.h.schmidt]

Hi Guys
Rojelio
I like your cap loader it has some likeness to what I made.Form follows function. You should be able to use two layers of pop cans in your Home-made Tap O Cap. I have a Forrester made one and a home-made one .Both will work with two layers. Maybe your die push through dia. is too small My Forrester is .206. The home-made one is .203 and highly polished. The 2ply cups work very well for me. They don't have the problems of the single layer cups.They don't blow apart. I know copper would work but I'm not going to stand the cost. I can make 45 2ply cups for 10cents. Free if I just pick the cans up.
wicket You can easily soften the cans up in a toster oven. A hour at 400 will do. They will smoke and stink though.
For myself I use the cans as is. The cans being painted on the outside and coated in the inside don't have to be lubed.I do like to lube the side that becomes the outside of the cup. A coat of Jhonson's paste wax is cheap and easy to apply and will make the forming easier. Could stop the punch through problem.
n.h.schmidt

[wicket]

Good to know about the aluminum n.h.schmidt, i tried a torch and didn't accomplish anything useful. Probably wouldn't have gone with aluminum anyway, it galls too easy, and i just prefer working with copper. It's funny, but buying sheet copper to make caps costs about 2-3 cents per cap, but if you roll out a copper penny you can make about nine caps from it if you work carefully. Not worth the trouble of doing it though, penny alloy requires constant annealing. What are you guys filling your caps with?

[Rojelio]

n.h.schmidt,
funny you should mention about opening up the die a little. I did that today. I went up one number drill size to .204 and polished it real well and now it will take a double layer of soda can and the caps are real strong. Before, with the single layer caps, you could crush them between your fingers. Not the double layer.
Also, my cap loader resembles yours because I got the idea from you when you posted a picture over on the tap o cap thread. Thank you!!! It sure beats fumbling around and spilling priming compound everywhere.
I also like your cap tester. It's pretty ingenious. My priming compound seem to be working fine. A little dirty, but, reliable. I'm using the potassium chlorate, sulfur, antimony sulfide mixed dry. I only mix enough to load about 35 caps at a time. I just need to figure out a better way to glue it in there. Maybe a tiny drop of super glue or something. More experimenting.......

[Texantothecore]

Can aluminum is quite hard as it has other metals in it to increase the stiffness of the alloy.

[wicket]

Maybe that's why i had trouble annealing it. 10 mil aluminum flashing might have worked better, and it's about as common and cheap as can metal. Not my problem anyway, i'm not looking to switch from copper.

[n.h.schmidt]

It was asked what I'm filling my cups with. I still use the toy pistol caps. The German ones seen to be the only one's I can get now. They are ok if used with a small scoop of BP in the cup. I now punch out one cap dot to put in first.Then the scoop of BP. One more cap dot on top of that. For the first cap dot I use a 1/8" paper punch you can easily get a craft shops or scrapbooking places. A lot less paper with that. When all is assembled the cups are placed in a large pistol primer shipping tray. I then spray them all with a heavy coat of hair spray(Rave).
Rojelio
Maybe the hair spray could hold your mixture in for you.
n.h.schmidt

[wicket]

The caps i tried came from Italy and seemed to be mostly grit, even priming the nipples with 4f didn't help, haven't found the German caps that folks seem to have better luck with. I press my charges dry with a disk of flash paper covering them, it holds things together and vanishes completely when the cap fires.

[n.h.schmidt]

Wallmart has the german caps.You have to read the fine print to know where they come from. Also the Dollar General has the same caps under a different name. I tried priming the nipple and gave it a go for a while. Sometimes it seemed to really work. You sure couldn't count on it though. These german caps aer not all that great.It's about all I can get.Where do you get yours?

[wicket]

I don't use toy caps n.h.schmidt, just experimented with them, i seem to recall getting them at Walmart though, a couple years ago. I use about the same mix as Rojelio mentions above, but with tin sulfide in place of the antimony compound.

[Ajax]

I wonder if a nipple primer with 4f would help?


Andy

[ofitg]

I just need to figure out a better way to glue it in there. Maybe a tiny drop of super glue or something. More experimenting.......

Rojelio, the KClO3-based primer mix used by the U.S. Army during the Spanish-American War incorporated 2% shellac as a binder. I would suggest a wet (alcohol) mix with shellac - after the alcohol dries, the primer compound will be a solid clump "glued" into the bottom of the percussion cap hull.

[Rojelio]

ofitg,
Thanks for the advice. I realize that that would be the proper way to do it. My only problem would be that I would have to devise another way to load the caps. If there is an easy way to measure out the wet charge and install it into the cup, I'd sure like to hear about it. I have tried the hairspray and it works ok I just don't think it would stand a lot of rough treatment before it fell out.

Here's a short video of one of my cap tests. It's actually louder in person than it sounds on the video.
woops, video didn't work, sorry

[ofitg]

Here's something I came up with -

I add a few drops of denatured alcohol to the mix and stir it with a toothpick, until it reaches a "thick sludge" consistency (similar to toothpaste). Now it's ready for loading into the empty percussion cap hulls.

I built a simple tool for loading - I took a 8D framing nail, filed off the point, and lathed a "skinny section" in the center of the nail. Then I took a short length of 5/32" brass tube (from the hardware store) and crimped one end down around the "skinny section" in the nail. After the nail and brass tube were joined together, I carefully filed off the other end of the brass tube so that when the nail head is pulled away from the brass tube, it opens up a small chamber which is 0.10 inch deep. When the nail head is pushed toward the brass tube (like a tiny syringe), the material in that chamber will be expelled.



I use a small knife blade to pack the moist "primer sludge" into the chamber of the loading tool, then I expel the sludge into an empty percussion cap hull. Next I use the butt end of a 9/64" drill bit to hand-press the sludge down into the base of the hull. Be gentle, it only takes one or two pounds of force. Allow the cap to dry out overnight and it's ready to use.

Naturally, it takes several seconds to load each cap, and that pile of sludge in the saucer will be drying out, so every three or four caps I will add a couple more drops of denatured alcohol to that pile of sludge to maintain the "toothpaste" consistency.

[Rojelio]

Thanks ofitg, that's pretty ingenious. I'll probably eventually end up doing something like that.

How is your stuff working out? Have you tested it much with live fire?

[ofitg]

Making my own caps has been an ongoing "hobby" for about 20 years, and I've tested small batches to evaluate changes in the procedure, but I don't shoot homemade caps on a regular basis. As long as I can get store-bought caps, I'd rather pay a few dollars and use my spare time for other things.

[wicket]

I like the speed and precision of loading primers dry, but pressing them makes me a bit nervous. Ofitg, have you ever tried mixing powdered shellac into the primer mix, loading dry, and adding a small drop of alcohol to bind the powder together once the cap's loaded?

[ofitg]

No, I haven't tried that..... but I don't see why it wouldn't work, as long as the shellac particles were finely ground and evenly distributed throughout the mixture.

I usually stir in 1/3 CC of liquid shellac from the hardware store (21% shellac solids by volume) with 33 grains of dry ingredients - KClO3, sulfur, antimony sulfide, grit & sodium bicarb - and then add enough alcohol to achieve the "toothpaste" consistency. If I'm doing the math correctly, that works out to roughly 3 percent shellac by weight.