Debugging my lantern pinion

[homebrewed]

A carbide bit would definitely either make a straight hole or explode. I didn't even think about carbide drills existing at sizes this small, but they do. It's not the worst idea, and carbide bits this size have larger shanks that would be better to grip in a chuck. Or probably large enough to grip in an ER32 collet for that matter. That's not a crazy idea, although the chances of the bit exploding are very high.

The work was just floating in the air, up above an empty chasm. I tried throwing a parallel under it, but I didn't have a parallel remotely small enough. Chuck spider. I need to think about that. Or a pot chuck could work. More to look at there.

Or I could just throw away a few inches of brass. I'm only making three of these, or whatever number I end up having to make to get three usable ones.

Good food for thought.

I too dislike wasting material when I don't have to, but sometimes you don't have much of a choice.

I've found that I sometimes can use smaller pieces by gripping them from the inside with an expanding mandrel. I have a mandrel set, and also have made a few. They're not too hard to make if you've got a lathe.

 

[gerritv]

A couple of things to try:
- Use a stub drill, shorter and less flex, preferably 135dg tip, these don't wander as much
- Use a 90dg spotting drill to make a pip before drilling, centre drills don't work for spotting, esp. tiny holes
- Make a spade drill, possibly from the spring wire. I don't have a referecne handy but these are typical clock and watch makers tools.

gerrit

 

[homebrewed]

A couple of things to try:
- Use a stub drill, shorter and less flex, preferably 135dg tip, these don't wander as much
- Use a 90dg spotting drill to make a pip before drilling, centre drills don't work for spotting, esp. tiny holes
- Make a spade drill, possibly from the spring wire. I don't have a referecne handy but these are typical clock and watch makers tools.

gerrit

I had thought about suggesting a spade drill but sort of dropped that idea after seeing that the holes are just .040" in diameter. Not easy to make or harden.

 

[gerritv]

A diamond stone or equivalent should take care of sharpening the wire, and a small blow torch and some veg oil takes care of hardening. Although it is likely the wire is hard enough already, he is 'only' cutting in brass.
You could hold the wire/drill in a pin vise in a chuck to save the trouble of more elaborate bushings, etc. Peck drilling, lots of retrations to clear chips. But basically a free drill as short as you want it to be.

gerrit

 

[homebrewed]

An unevenly-sharpened dril, no matter what its style, won't drill straight. Hand-sharpening is pretty unlikely to produce a drill that will work well, especially considering that the spade portion will be half the width of the wire -- .020". Sounds pretty challenging to me but I'd love to be proved wrong!

 

[gerritv]

If someone is working with sizes that small they would generally have an eye loupe to see the work. A few light strokes, look at result, a few more and you are done. Not an uncommon task for clock and watch makers, even in the 1700 and 1800's and earlier.

George Daniels in Watchmaking pg 34 describes sharpening as a light stroke on one side, a light stroke on the other side and then check. This is e.g. for drills from 0.1mm to 2mm. Use a pin vise to hold the drill. Spade/flat drills don't grab the matersial, a big problem with brass.
As for cutting speeds, 500 rpm in brass is a starting point, 300 rpm in steel. High rpm translates to heat, the skill comes from applying just the right amount of pressure to drill.

An example of purchased one: https://perrinwatchparts.com/collec...ories/products/mascot-flat-pivot-drills-28364, starting at 0.008"

An example of making one:

Gerrit

 

[dewbane]

An example of making one:

Clickspring is my inspiration, and hero. Looking at his setup is what inspired me to venture down this road. He has some equipment I lack, but nothing outrageously exotic. I tracked down a copy of that John Wilding book, and I have the plans for that clock. I'm starting with something much, much less ambitious though. "Building an American Clock Movement" by Conover. He cuts a lot of corners in his design, so you can just build something and enjoy a success. It uses commercial pallets, and I bought a commercial escape wheel to mate to the pallets, so I have a fighting chance that my escapement will actually work. (I've built three laser-cut wooden kit clocks, and the escapements never work well.)

If I want to go all Clickspring and make every single part myself (I actually don't, and I'm totally fine with using commercial screws and pins) I can always use the commercial escape wheel as a template to clone with my own part. I may do that much. Using the commercial one seems too much like cheating, but anyway, the point of the design is to keep it relatively simple. I think it will be a good first project. I'm encouraged by what I've been able to produce so far. It ain't there yet, but it's not too far off.

Anyway, your idea of sharpening a bit of the music wire is totally sound. I'm already doing that to make reamers elsewhere, and one of those would probably cut its own hole. I don't feel like it's overly difficult to get them sharpened evenly.

Also, after mulling it over for a few days, I did pull the trigger on an ER32 collet setup across the board, and an additional ER16 setup for the mill. I think I'm going to be glad I did. No, this isn't a good time for a major investment, but I slept on it for a few nights.

 

[gerritv]

The main thing is to start building something. Looks like a decent clock.
I am presently building a Synchronome electric clock. Someone gave me the cast iron casting of the frame. Everything else is from scratch including the screws. Making tools as I go along to provide a good mix of challenges.

John Wilding's books are great, he also doesn't use esoteric machines and tools. And illustrates making tools as needed. Pricey books but worth it.

gerrit

 

[dewbane]

The main thing is to start building something. Looks like a decent clock.
I am presently building a Synchronome electric clock. Someone gave me the cast iron casting of the frame. Everything else is from scratch including the screws. Making tools as I go along to provide a good mix of challenges.

John Wilding's books are great, he also doesn't use esoteric machines and tools. And illustrates making tools as needed. Pricey books but worth it.

gerrit

I'm debating whether to go to the extreme of making B&S style cutters with the correct profile, or just using fly cutters. If I use fly cutters, I need to make a straight holder. I'm probably going that route. I also need to make a new gear cutting arbor. What I came up with last time (learning to use a dividing head making test gears) was a split and threaded rod with a machined section to hold the blank that slipped tightly into a threaded section to clamp everything together. I think the concept is sound, but I need to do a more accurate job of making the next one, and I need to size it to the wheels this project calls for.

I need to make one of those depthing gauges, and I need to finish my bluing tray. I'm sure this is just the tip of the iceberg making tools for this project.

Come to think of it, I have a very crappy wood-cutting bandsaw that's basically worthless. I can't keep a blade on it for two minutes. It's junk. But if I put my thinking cap on, I bet it could be the foundation of a filing machine.

 

[gerritv]

I Ibuilt a Eureka relieving device to make cutters for T2.5 timing pulleys. 12 tooth cutters. A good inbetween that and fly cutters might be Deans Photographica description of an earlier method: http://www.deansphotographica.com/machining/projects/multipoint/multipoint.html . He credits this article by David Creed who credits others https://vdocuments.net/cutter-making-david-creed.html?page=11 Clickspring eventuallly also did a vid but I didn't see any credits from him (one of the reasons I stopped watching his stuff)

If you want even more, Malcolm Wild's book is excellent.

Sorry for adding to the potential decision paralysis, there are so many ways to make gears
Gerrit