Help with milling 1/8" diameter brass pieces

I've been a locksmith for 40 years now, and I usually work out my own solutions, but this time I could use some help figuring out a better one.
I need to modify several thousand "finger pins" so I can use keys from 2 different series in the same locks. The pins are made of a hard, high-nickel brass called "nickel silver" about 1/8" diameter (actually 0.115") and are roughly 0.33875" long, give or take 0.00025". (Okay, I'm kidding. Contrary to myth, nothing in even a high-security lock needs to be accurate to more than 0.003".) They have a short hole in one end and a "finger" sticking out of the side of the other end. There are a pair of cuts 1/16" wide and 1/16" deep on each side leaving a bar that fits into a slot in another piece called a sidebar. You can easily find a picture thanks to someone misspelling the caption on a photo of one. Use Google Images to search for "heres's finger pin" and it will be one of the first images in the results.
Anyway, I need to make a second pair of the same kind of cuts in around 500 of each of 4 shapes of pins and am wondering if there is a better way to do it than what I've been doing.
Currently, I've modified a quick-release vice to hold 1 pin and mounted the vice on a lazy Susan so I can get at both sides of the pin. I put the pin in, and then use a Dremel flex-shaft tool spinning at 35,000 RPM with a 1/6" carbide 2-flute end milling cutter to make the cut on one side, spin the vice and make the cut on the other side. I wear a double magnifier on my head to see what I'm doing, and, well, my hands aren't as steady as they used to be, so the cuts don't always end up as neat and clean as I mean them to be. If the cutter is new, I don't have to deburr, but after it starts to get dull, I need to brush off the burrs on each pin by holding it in a pair of tweezers against the wire wheel that I use for brushing off keys. I take a few more seconds to test each pin before putting it in my pinning kit, since a bad pin in a lock cylinder will waste a lot more time than testing it before the lock is closed up.
I can modify and test 60 finger pins in two or three hours, and then I have to stop and do something else. (I would not make a good assembly line worker!)
Questions: Is there a machine that could fit on my workbench that is designed to repeatedly make precise cuts on tiny pieces of metal like this?
If not, is there a place to look for designs for jigs or tool holders so I can mount the end of the flex shaft in a way that will limit how far it moves? I'd like to have something where I slip in a pin, swing the tool down and up to quickly make the cut, and then slide out that pin and pop another one in.
Is 35,000 RPM the best speed to use when making 1/16" cuts 1/16" deep in nickel silver? I saw a pneumatic pencil grinder that spins at 100,000 RPM, which might make cleaner cuts faster, but might have some other problem I don't know about. The cuts are so small and take so little time, that heat may not matter, but I have no experience with such a tool.
Is there a formula or something to figure out what is the best working speed for a particular kind of metal and size of cut?
The carbide cutter manufacturer claims it is for cutting "Aluminum, Carbon And Tool Steel, Cast Iron And 300 Or 400 Series Stainless Steel," but no mention of brass alloys. Is there a kind of milling cutter that is better for brass?
Thank you for any help you can provide. Lee
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On Fri, 22 Jun 2012 20:04:22 -0700 (PDT), LeeAtWork

different series in the same locks. The pins are made of a hard, high-nickel brass called "nickel silver" about 1/8" diameter (actually 0.115") and are roughly 0.33875" long, give or take 0.00025". (Okay, I'm kidding. Contrary to myth, nothing in even a high-security lock needs to be accurate to more than 0.003".) They have a short hole in one end and a "finger" sticking out of the side of the other end. There are a pair of cuts 1/16" wide and 1/16" deep on each side leaving a bar that fits into a slot in another piece called a sidebar. You can easily find a picture thanks to someone misspelling the caption on a photo of one. Use Google Images to search for "heres's finger pin" and it will be one of the first images in the results.

each of 4 shapes of pins and am wondering if there is a better way to do it than what I've been doing.

vice on a lazy Susan so I can get at both sides of the pin. I put the pin in, and then use a Dremel flex-shaft tool spinning at 35,000 RPM with a 1/6" carbide 2-flute end milling cutter to make the cut on one side, spin the vice and make the cut on the other side. I wear a double magnifier on my head to see what I'm doing, and, well, my hands aren't as steady as they used to be, so the cuts don't always end up as neat and clean as I mean them to be. If the cutter is new, I don't have to deburr, but after it starts to get dull, I need to brush off the burrs on each pin by holding it in a pair of tweezers against the wire wheel that I use for brushing off keys. I take a few more seconds to test each pin before putting it in my pinning kit, since a bad pin in a lock cylinder will waste a lot more time than testing it before the lock is closed up.

Sure. It's called a 4-axis CNC mini-mill.
You'll get the rest of the info from the real metalmen here.
-- Always bear in mind that your own resolution to succeed is more important than any one thing. -- Abraham Lincoln
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On 6/22/2012 8:04 PM, LeeAtWork wrote:

different series in the same locks. The pins are made of a hard, high-nickel brass called "nickel silver" about 1/8" diameter (actually 0.115") and are roughly 0.33875" long, give or take 0.00025". (Okay, I'm kidding. Contrary to myth, nothing in even a high-security lock needs to be accurate to more than 0.003".) They have a short hole in one end and a "finger" sticking out of the side of the other end. There are a pair of cuts 1/16" wide and 1/16" deep on each side leaving a bar that fits into a slot in another piece called a sidebar. You can easily find a picture thanks to someone misspelling the caption on a photo of one. Use Google Images to search for "heres's finger pin" and it will be one of the first images in the results.

each of 4 shapes of pins and am wondering if there is a better way to do it than what I've been doing.

vice on a lazy Susan so I can get at both sides of the pin. I put the pin in, and then use a Dremel flex-shaft tool spinning at 35,000 RPM with a 1/6" carbide 2-flute end milling cutter to make the cut on one side, spin the vice and make the cut on the other side. I wear a double magnifier on my head to see what I'm doing, and, well, my hands aren't as steady as they used to be, so the cuts don't always end up as neat and clean as I mean them to be. If the cutter is new, I don't have to deburr, but after it starts to get dull, I need to brush off the burrs on each pin by holding it in a pair of tweezers against the wire wheel that I use for brushing off keys. I take a few more seconds to test each pin before putting it in my pinning kit, since a bad pin in a lock cylinder will waste a lot more time than testing it before the lock is closed up.

mount the end of the flex shaft in a way that will limit how far it moves? I'd like to have something where I slip in a pin, swing the tool down and up to quickly make the cut, and then slide out that pin and pop another one in.

nickel silver? I saw a pneumatic pencil grinder that spins at 100,000 RPM, which might make cleaner cuts faster, but might have some other problem I don't know about. The cuts are so small and take so little time, that heat may not matter, but I have no experience with such a tool.

Tool Steel, Cast Iron And 300 Or 400 Series Stainless Steel," but no mention of brass alloys. Is there a kind of milling cutter that is better for brass?

if you could make an accurate drawing of what you want you could probably get them made for a surprisingly cheap cost
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Would probably be a perfect job for someone with a swiss turning center, I could probably knock them from 12 ft bars of raw bar stock in a minute or two per part but I've already got more work than I feel like messing with as it is.
Anyways, pretty sure you're talking about the "notches" in this part:
http://bp3.blogger.com/_Vn-QxkKF9KQ/RwmMBstmvkI/AAAAAAAAAOM/7A7WePt6m8s/s1600/DSCF5572.JPG
If so, you might want to buy yourself the smallest, cheapest mini-metal-lathe that you can find and remove the headstock and tailstock from it altogether, and then mount a pair of dremel-type tools in their place, on vee blocks, facing towards each other, similar to what is commonly known as a "duplex milling machine"
Then make a jig to hold your part in the toolpost, moving the part left to cut one notch then to the right to cut the other...simple carriage stops or even a pair of c-clamps could be used to control depth of cut....
Or, a similar arrangement could be setup on an say...an old hardinge second op lathe, in which case you would use a lever type production slide instead.
Good luck have fun glad it's not my problem.
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I am just an amateur machinist, but my thoughts are to either use a dremel drill press attachment: (Amazon.com product link shortened) or a small high speed mill like this: http://www.proxxontools.com/store/pc/viewPrd.asp?idcategory1&idproductc
Make the fixture in two parts. One part is a strip that holds multiple pins and has some sort of registering holes or notches corresponding to each pin, the other part is fixed to the table and has features the first part can mate with. Insert the strip in the first position, mill, insert in second position, etc. until whole row is done. Then flip over to do the other side.
Use a carbide cutter. Tumble deburr rather than wire brush each individually.
On second thought, when you are done with these, don't you end up with a continuous slot on each side running across the width of the pin? If so, just use a slitting saw. Line up all the pins in a long fixture, and run them past the slitting saw.
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OK, I'll take a whack at this: How about you hold the pin in a collet in a collet block such as this: http://compare.ebay.com/like/350553632224?var=lv&ltyp=AllFixedPriceItemTypes&var=sbar ? you could put a depth stop in the collet to hit that axis correctly. Then make a plate with either some stops fastened to it or a pocket milled into it to allow the collet block to move the 1/16" depth of your cut (that takes care of another axis). Now cook up a fixture to hold the dremel (seriously, dremel? you want to look at http://www.ramprodinc.com for some seriously good and not seriously expensive alternatives) Anyway, you want to come up with a fixture to hold the rotating mill in the right place. It really wouldn't be too big a deal to make it adjustable in three axes, if you wanted to - f'rinstance, you could mount the dremel-holder to the plate with a couple of bolts going through the holder into threaded holes in the plate. make the through- holes a little oversized. Loosen them just a smidge, and tap the block into position with a tiny hammer. For the third axis, you could just use shims.
So, you clamp the pin into the collet, fire up the dremel, slide the collet block to one end and you've made one cut. Flip the collet block over, and you've made the other cut. And, as was said by someone else, tumble deburr the whole mess at once rather than wire-brushing each piece.
That's my $.02 worth, hope it helps.
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-OK, I'll take a whack at this: How about you hold the pin in a collet -in a collet block such as this: http://compare.ebay.com/like/350553632224?var=lv&ltyp=AllFixedPriceItemTypes&var=sbar
Accurate but slow.
I've clamped a row of small pins upright in the milling vise with a block of wood or hardboard on the moveable jaw side that compresses to grab -all- the pins. They can be pre-aligned against the inside corner of a square and held in place with tape.
If their lengths vary and you want the tops to line up, clamp them in a small insert vise upside-down, with thin parallels under the vise so the pins extend beyond the jaws. The pins can be stuck upright onto double-sided tape to make handling them easier.
jsw
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-I've been a locksmith for 40 years now, and I usually work out my own solutions, but this time I could use some help figuring out a better one. -I need to modify several thousand "finger pins" so I can use keys from 2 different series in the same locks. ...
Here is some discussion and comparisons of hobby-sized machine tools. Non-intuitively the larger ones may be more precise than the smaller (cheaper) ones. http://littlemachineshop.com/
jsw
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On Friday, June 22, 2012 8:04:22 PM UTC-7, LeeAtWork wrote:

different series in the same locks. The pins are made of a hard, high-nickel brass called "nickel silver"...

Two ideas: get a jeweler's lathe (Taig is a common brand); they're tabletop size. Either hold the pins in a collet (using a collet and a stop is VERY much easier than a vise), with the cutter-on-a-Dremel mounted to the tool carriage, or put the cutter in the lathe spindle and move the pin past it with your vise fixed to the tool carriage. If you hold the pin in the lathe spindle collet, you can position for the second notch using the lathe spindle indexing feature (common only on jeweler's lathes).
Or, go to a machinist with a real shop, and see if he can use nickel silver (cupronickel) welding rod for stock and churn out a few hundred automagically. Or, even ask the lock manufacturer to make a run of custom parts; you KNOW they have a screw machine setup for doing this.
Remanufacture with all the handling of small parts is ... always going to be inefficient.
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It's also known as Monel.
Welding rod is hard drawn, locally available and great for turning small parts on a collet lathe, but it's made in only a few fractional sizes.
jsw
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    Be sure to get the alternate spindle for the Taig which accepts WW series (jeweler's lathe) collets, which are much better for this sort of thing than the collets which come with the Taig's standard spindle.

    Put the collet in an indexing head on the carriage -- and put stops to allow offsetting to one side for one cut, and to the other side for the second cut.

    I know it to be on the true jeweler's lathes, but I don't have such a feature on my Taig -- rather an old one as they go. However, it should not be that hard to add.

    I get the impression that there is an elbow in the part which would make it more difficult to make from plain rod stock -- unless you used silver solder to join two pieces.

    :-)
    Of course -- but it may still be the best approach, depending on how happy the manufacturer is to deal with individuals -- locksmiths or no. And it sounds like he wants to add an extra feature not present on the standard parts.
    It is a fascinating lock which I have not seen before. Where are these used? Looks like it would be immune to a picking gun. :-)
    Enjoy,         DoN.
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On Fri, 22 Jun 2012 20:04:22 -0700 (PDT), LeeAtWork

First, you need to turn the Line Length on in your Usenet software so it wraps at around 72 characters...
Second, if you're using these in bulk, they Have To Be commercially available for a dime each. You just haven't looked hard enough, or in the right places. ;-P
Put on your Deerstalker hat and fill your Meerschaum, and get to looking, Sherlock. One of the OEM lock makers has them hidden in the Spare Parts and Errata section at the back of the catalog - then they wonder why they don't sell.
Then you open the package, drop them in, and they work.
I'm an Electrician - If I need the special ceramic wirenuts or the special ceramic DIN terminal strip block for the wiring inside an oven, I go buy them. Not worth my time taking up ceramics and buying a kiln and all the specialized gear you'd need to make them, when they're available cheap and as many as I could possibly want right there on the shelf.
Some days it just isn't worth the effort to chew through the restraint cuffs...
--<< Bruce >>--
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