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chuckknigh
12-01-2003, 12:37 AM
Has anyone ever built a router where the spindle was below, rather than above, the machine?

Yeah, I know this is a weird question, but here's why I had the thought.

I have several inexpensive watch movements...well, honestly, I have several dozen on hand. They're all undecorated. What makes a watch movement expensive is not the mechanical parts, but the level of finish and decoration done to them. I've included a picture, below, of a particularly beautiful one, from 100 years ago.

Look at this watch...it's beautiful, isn't it? This type of finish is done with an emery disk and a watchmaker's lathe, with a specialized version of a cross slide vise. Almost no pressure -- the decoration is basically just light sanding. Well, you know what I'm thinking...

Problem. If the finishing was done from above, the watch would require extensive cleaning...the microscopic dust would contaminate the movement HORRIBLY. I could probably clean it out, but why do it if I can avoid the problem altogether? Maybe it's just wishful thinking on my part, but I'd like to do this level of finish with minimal disassembly.

So, my thought is to mount the router *underneath* the machine, and hopefully the microscopic metal dust will fall *down* instead of floating up. Maybe a vacuum would help with this...

Another alternative would be to disassemble the watch movement, mount the plates on a carrying plate, machine them as separate pieces, and then reassemble the watch. Simple on a time only movement, but MUCH harder on the more complicated ones...

Anyway, has anyone ever seen a router with this type of arrangement...spindle underneath? It seems a logical alternative, but undoubtedly there are some practical concerns that would have to be addressed. Anyone have any ideas?

-- Chuck Knight

P.S. This watch (not mine) is from the turn of the last century, and sold BACK THEN for over $100. It's one of those super-accurate railroad watches that the engineers used to keep the trains running on time. They're even more beautiful in person.

ToyMaker
12-01-2003, 09:41 AM
I think you said it when you mentioned microscopic metal dust. It is going to go with the air flow. Maybe a strong vacuum would get it all - but maybe not. I think you would have to give the piece a thorough cleaning to be sure.
Would an ultrasonic bath remove all the dust?

robotic regards,

Tom
= = = = =
God has not called us to see through each other, but to see each other through

chuckknigh
12-01-2003, 11:01 AM
You're right about cleaning the watch -- that's what I'm trying to avoid. Basically it involves taking it completely apart, cleaning each piece individually with a toothbrush (ultrasonics work even better, but I don't have one), reassembling, reoiling, retiming...it's a fairly involved procedure.

Nevertheless, like I said, cleaning a time only movement is not that bad. Consider one of these, though. It's a Breitling chronograph movement (watch + stopwach complication) and has 150-200 parts, depending on the model. This is an expanded view that someone posted on the web...

I wonder if machining it upside down, and maybe supplying compressed air on one side & vacuum on the other, would give an even greater airflow? I'd really prefer not to have to take a complicated one like this apart, if I could avoid it...

-- Chuck Knight

HuFlungDung
12-01-2003, 12:19 PM
I don't think gravity has much to do with preventing the dust from getting into that. You'd be better off to fill it with lard, and melt it out afterwards :D

balsaman
12-01-2003, 01:21 PM
Just flip your machine, when done, flip it back.

Seriously, that thing will get full of dust no matter what. My spindle is on top of the work, and it's full of dust...

Eric

ToyMaker
12-01-2003, 01:41 PM
I play with wind up clocks - my eyes won't let me do anything as small as a pocket watch :( . The most complex one I have is a triple chime with time, chime and strike trains.
I didn't like the prices of available ultrasonic bath cleaners so I made one from an ultrasonic humidifier ($5 at a thift store) and a 1 quart stainless steel tub from a steam table. Works well enough for me, but makes the dogs duck-and-cover :) .

robotic regards,

Tom

chuckknigh
12-01-2003, 02:16 PM
Maybe I'll just take off the back plates, and machine them independently of everything else.

I was really trying to avoid disassembly, but I am VERY concerned about contamination, and I don't think it's avoidable.

Considering the extremely low pressures involved, would it be practical to attach the plates to the surface of something "firm" like wax or modeling clay, and just machine them that way? The "undersides" are not necessarily flat...

-- Chuck Knight

Reboot
12-01-2003, 04:56 PM
Hi Chuck

Reading your post has finally prompted me to reply with my own first post.

I would share your concerns about contamination, I don't think you could
adequately guard against any debris entering a delicate movement even with
vacuum hoses. I would imagine that even one or two microscopic abrasive
particles would render such a delicate instrument at best inaccurate, and
at worst useless.

As to your last point regarding mounting of small parts for machining, I
machine some very delicate parts in ceramic and have recently started to use
a product recommended to me called Aqabond.
This is a water soluble thermoplastic adhesive which melts at low temperatures.

Here is their website.

http://www.aquabondtechnologies.com/adhes.htm

I have been using Aquabond 55, but I think for metal parts Aquabond 65 or 85
might be better.

I'm not connected to this company in any way, just very impressed with their
products.

Hope this is of some use.

chuckknigh
12-02-2003, 12:37 AM
Well, actually it acts like a sandpaper grit, between the jewel and the pivot.

Basically, the fastest moving part is the "tick tock" part, the escapement, which ticks 4 timex per second in most mechanical watches, which is 14,400 times per hour, 126,230,400 times per year. Ruby jewels are hard, but they're not indestructible... Contaminants are not welcome in a mechanical watch. :-)

I'll take it apart...

-- Chuck Knight

cnczane
12-11-2003, 03:49 PM
I don't think dust obeys the Law of Gravity.

I'm serious.

I suspect it pays more attention to air currents.

Which suggests a slight vacuum might just be enough.

yukonho
12-11-2003, 06:02 PM
What about mounting a strong magnet rear the end of the cutter. That would attract all the little metal chips. Unless of course these things are made from non ferrous metal.
co

chuckknigh
12-12-2003, 12:22 AM
Most plates are made from steel, and often plated. Since magnets and watches don't mix, I've never tried to specifically magnetize the plates...but since they corrode, they definitely weren't stainless. :-)

I think disassembly is going to be the answer, though.

-- Chuck Knight