Mill for watch work

[link55]

I'm a hobbyist watchmaker and I'm looking at getting a mill. I will be doing work mostly in brass, but would like the flexibility to machine larger parts for other projects as well. Possibly even some light steel work. The watch work would be mostly drilling at very precise locations within a relatively small area (generally no larger than 40mmx40mm).

I'm looking at CNCing either a Proxxon MF70, Sieg X1, or Sieg X2. Can I get the X1 or X2 to be accurate enough to machine such small items without major improvements? The spindle speed of the MF70 seems attractive, and it seems much easier than the other options to convert to CNC.

Does any have any input? Price isn't factor when considering any of these three, it's more of a which one is the best fit scenario. It seems like the MF70 would be the best option for the small precision items, but if I can get the flexibility to mill large parts as well with an X1 or X2 it would be worth the extra money.

[Stepper Monkey]

Neither of those are going to really be appropriate for what you are doing, the Proxxon is not very rigid, the X1 and X2 are definitely not what you need at all.
If you have the budget there are machines like the Minitech with the NSK spindle, and the Model Master mills would work well for that job too. Both are unfortunately in the $10k territory, but are definitely the right tools for that job.

[dkochan]

How much rigidity do you need for watch parts?

Link55: Would love to see pics of your work. I played around with watchmaking for a bit, took the TZ level 1 course. Amazing how small and delicate some of those parts are!

Dave

[Stepper Monkey]

Originally Posted by dkochan How much rigidity do you need for watch parts? Dave

Not much actually. The Proxxon can do a surprising amount for what it is, but with a frame made from half a dozen pounds of zinc castings it just doesn't have the ability to produce a good smooth surface finish on even the smallest metal parts. This can be very important for watchmaking.

I don't know what the budget is here, there are machines that fit in between that will work well too, but those two I mentioned really are the right tools for the job if you can afford them.
Two machines in the about the same price range as those solutions he originally listed would be the Sherline and the Taig. Not perfect for the job, but adequate, and a thousand times better suited than the alternatives originally listed.

[jalessi]

"Proxxon MF70, Sieg X1, or Sieg X2. Can I get the X1 or X2 to be accurate enough to machine such small items without major improvements? The spindle speed of the MF70 seems attractive, and it seems much easier than the other options to convert to CNC."

None of the above machines would be a good choice for a watch maker.

Stepper Monkey's advise to you is very good.

If you don't have the budget the Taig might get you by however the Minitech would be the much better choice.

Make sure you do your homework before wasting lots of time and money on a less expensive import that can not come close to watchmakers tolerances without extreme modifications.

Jeff Alessi

[dkochan]

Originally Posted by Stepper Monkey Not much actually. The Proxxon can do a surprising amount for what it is, but with a frame made from half a dozen pounds of zinc castings it just doesn't have the ability to produce a good smooth surface finish on even the smallest metal parts. This can be very important for watchmaking. I don't know what the budget is here, there are machines that fit in between that will work well too, but those two I mentioned really are the right tools for the job if you can afford them. Two machines in the about the same price range as those solutions he originally listed would be the Sherline and the Taig. Not perfect for the job, but adequate, and a thousand times better suited than the alternatives originally listed.

I didn't realize the Proxxon was quite such a, um, lightweight. Sorry about that.

The Minitech and the Model Master both look like a good bet, and the Taig could probably be coaxed into doing the job. Even 10K RPM's is going to seem slow in that scale of work. And the accuracy is going to need some hand-holding.

[Stepper Monkey]

Shipping weight for a complete MF70 Proxxon mill with accessories is 15.5 lb. That is the whole mill package. I am only guessing at the weight of the underlying zinc structural castings, but 6 pounds or so is certainly in the right ballpark.
It sounds like a just toy, but it can actually pull off some neat stuff for the person cutting only very small waxes, foams, plastics, and doing engraving. Some model and diorama builders use them to good effect.
Not too good for watchmaking though.


The trick to using a Taig or Sherline for this work is to unclip the stock spindle/motor combo (or just order it without one) and replace it with a 25k+ spindle from Wolfgang Engineering or similar. The Proxxon I/BE is another inexpensive option good to about 20k. Both are cheap options if you want to avoid the thousands an NSK spindle will run, and both can just clip right to the dovetail with the proper mount, no mods necessary.
The machines still require regular adjustments and maintenance to keep it all tight though, something the more expensive machines don't generally ever have a problem with. Both type are capable of the same high quality of work, there is mainly the very serious matter of time involved in the tweaking and keeping the cheaper units adjusted and true if you are using it in a professional environment.

[dkochan]

I am a former Taig owner, now Tormach owner, and would sincerely love to be a Haas MiniMill owner. Not the biggest machines on the block. But 15.5 lbs just blows my mind!

[link55]

Thanks for all the responses so far. This project was done with a manual (as far as I can tell) Proxxon MF70:

http://web.ticino.com/dcorson/watch/..._files/WN1.htm

I am not set on any of these three mills. I don't have a set budget, but would like to stay around $1,000 pre-CNC since this will be my first mill. I have considered the Sherline, but the spindle speed didn't seem high enough.

I'll take a look at some of the other recommendations.

[link55]

Also worth noting is that I'd really be more interested in using this CNC drilling (plates, dials, etc), most of the things I'd be doing can be done with a lathe. There won't be any serious milling going on.

[Stepper Monkey]

That was some amazing work. I see the gears were cut on a manual MF70, but I very seriously doubt those plates could have been. Some very clean work there. I'm wearing something built up from most of a 2824 ebauche myself right now, so I can see what size those really are up close and that is some damn tiny work!

I think you can easily stay under $1000 pre-cnc. Although the Sherline headstock does have an adapter to make it run to 10k RPM like the Taig, that is still far too slow, and like the Taig the headstock is far too big and too cumbersome for what you need.

Look at this; http://stores.ebay.com/Wolfgang-Engineering

The spindle fits in the mount, the mount simply clips to the Z slide using the same standard mounting point. He makes both a Sherline version and a Taig version to attach to the factory mounts. No mods, takes five minutes to attach.
It is actually slightly cheaper than the standard headstock to get this setup, so you can simply order a machine from the manufacturer minus headstock assembly (they do it all the time, it's not an uncommon request from people like us) and then fit this, and it is still slightly cheaper than a stock machine.
Both of those choices will run about a grand. If you happen to be unlucky and run into the rare dealer that is not willing to ship minus headstock, simply find another one. It is a very commonly filled request, but on occasion a sales guy will try to BS you into buying the whole package saying they only ship one way from the manufacturer.

[Mike Stevenson]

link55,

Check out this video of an NC program I wrote and verified for another forum user here who is making a large clock gear:

YouTube - vericut clock part

YouTube - vericut clock part