Step collets

[TEACLOCKS]

Does any one make step collets for CLOCK wheels ?

 

[gvasale]

Well, depending on how bad you want one, you might be able to have one made. I needed one several years back. MSC ordered one from Hardinge to 3AT specs. Cost was $200.00 then. It is something you have to finish, that is, cut your own step, or steps. Believe me, it can be a lifesaver so to speak. I needed it to hold an escape wheel, and it worked out well.

 

[TEACLOCKS]

Thank you

 

[Jerry Kieffer]

Does any one make step collets for CLOCK wheels ?

Some years ago I made a couple of large wheel chucks by silver soldering a disc on the end of a collet. It was then machined and slit to match the collet slits. Through this process I quickly learned that a large chuck required a large collet to be practical. That in turn required a larger lathe than I wanted to use for the work I normally do on clock wheels. I also had the same problem as with my WW wheel chucks. No matter how many you have, half the time you just don`t have the right one or right size.

Personally I have found that the use of four jaw self centering lathe chucks with machinable jaws was a better solution. I prefer four jaw self centering over three jaw because of greater work piece support. This method has two major advantages over typical wheel chucks. First even though it takes a minute or two to take a light cut for fitting, the wheel fits perfectly. This in turn prevents most chances of damage.
Second is accuracy. Normally working accuracy is the accumulation of bearing runout, spindle runout, collet runout and mounting issues. By taking a light cut on chuck jaws, spindle runout and collet runout are eliminated leaving only bearing runout. Whenever I have needed to hold a wheel, mounting accuracy has always been critical.
Four jaw self centering chucks provided with soft jaws can be difficult to find for some machines. A couple of common readily available examples are Taig and Sherline that can be used with adaptors for most equipment applications.

TheTaig four jaw self centering chucks come with inexpensive replaceable aluminum jaws. Sherline`s can be ordered with soft oversized steel jaws. Soft jaws are also occasionally available though large machine tool supply houses for various brands and types of chucks.

Wheels can be suspended or elevated for machining purposes by installing aluminum posts in machinable jaws. (Attached Photo) This allows for accurate transfer from lathe to mill at will, without remounting. The wheel in the photo is held in place by machining a "V" groove on the inside of the posts. When I first tried this, I was very surprised at the minimal pressure required to securely hold a wheel with aluminum posts. Only finger pressure is required on the scroll to safely/accurately hold a wheel for normal machining procedures.

Please Note
Normally for holding the type wheel in the photo, the "V" groove would be much deeper. I am busy in the shop and did not take the time to install the jaws with the deep groove post`s.

Jerry Kieffer

 

[Smudgy]

If you only need to mount a wheel or two then you can mount a piece of wood and bore a recess for a tight fit into it. It will only be good for the one mounting (unless you need to mount a larger wheel), but for one-offs it beats paying for a step collet.

 

[Sterling]

I was going to suggest polypropelene (or some other soft plastic).

 

[gvasale]

While there have been some creative/alternative solutions, the step chuck insures the grip is nearly 100 % of the wheels perimiter. The cost of my step chuck in 3AT is high because of the lathe it fits, an Atlas 10F. If you are lucky enough to have a lathe larger than a Sherline or Taig or other of the small work envelope machines, say something that takes a 5C collett, then the step chucks are very modestly priced, at about 1/3 of what it cost me.

Other issues/ potential issues are runout. If the outside of your wheel is running true, than the arbor has got to run as true as the spindle bearings allow, if its not, then the arbor isn't centered properly, however you should be able to turn it in and have both concentric.

Seems to me that this is the fastest easiest way to insure the above statement is met. On the other hand, dialing in 64 teeth or more/or less has got to be a really tough job, but with the 4 jaw you can dial in the arbor, but not the perimiter.

 

[Sterling]

Just out of curiosity, are you talking about the collet on the right in this photo:

http://www.sterlingmetalworks.com/lathe/IMG_2207%20(Large).JPG

 

[berntd]

Sorry to hijack for a moment...

What is the 5th from the left for? I have a number of these in different sizes.

Regards
Bernt

 

[Sterling]

I thought maybe a pocket watch crown (winder) chuck without the top part, but I thought those were threaded on the outside.
That collet has no taper or threading on the inside, and looks to have been user-cut into thirds. Are yours all machine cut (or user cut) into thirds, or not at all?

...again, sorry for the hijack!

The large "step" collet (even though it just has one step, lol) is extremely hard. I would have imagined that if it were expected to be cut to size by the user, it would be mild steel, annealed. It is hard as glass!
It puzzels me why these things were not made of brass.

 

[berntd]

Hi Sterling

..and so the hijack goes on...
Mine look that the one in the pic number 5 and they are professionally made and seem never used, stamped Borley with numbers as well. They have a modern matt zinc finish, like something you would buy in a hardware store. Cuts are the same depth as for normal collets

Regards
Bernt

 

[Dave B]

Back to the original question. A number of years ago, I had occasion to need to grip an escape wheel, and wound up sticking it to a homemade face plate with shellac, much as you would do if turning using a small jewelers cement chuck. (I drilled the center of the face plate to clear the arbor and pinon.) If I had it to do over, though, I'd use repositionable spray mounting adhesive or something of that sort, because I had a devil of a time keeping the shellac warm enough to get the durned wheel centered.

 

[Ansomnia]

Does any one make step collets for CLOCK wheels ?

TEACLOCKS, I'm going to come back to your original question.

I'm curious and would like to ask why you need step collets for clock wheels. What are you trying to do with the clock wheels?


Michael

 

[Jim DuBois]

Teaclocks,

To your original question regarding step collets for clocks, Levin sells collets up to 1.5" dia that can be used as step collets. Derbyshire sells step collets in yet larger sizes, or did in the past. Schaublin sells step collets up to nearly 6" in diameter, but they only fit Schaublin lathes.

I have some fair number of Levin and Derbyshire 10mm step collets, and they are great for smaller sizes of wheels. However, for anything larger than about 1.25" I usually use a Levin 6 jaw bezel chuck that has a capacity of about 2.5" and is accurate to less than .001".

All these solutions are expensive. The Schaublin solution is perhaps the best solution but it is very expensive...very... a new model 102 with a modest number of accessories can easily exceed $25k, with fully accessorized exceeding $60k. A bit out of my hobby budget....

 

[Dave B]

TEACLOCKS, I'm going to come back to your original question.

I'm curious and would like to ask why you need step collets for clock wheels. What are you trying to do with the clock wheels?


Michael

I revisited my old notebook to see why I needed to grip the escape wheel. The center bushing was oval, because someone had tried to drive it off the (broken) arbor, and got it bent. I had to turn off the riveted boss before I could make a new bushing and arbor. This was in a clock that was made in the mid-1700's, and I didn't want to fit an oversized arbor to what was an otherwise good example of an older movement.

So there's an example of why one might want to grip a clock wheel.

 

[Ansomnia]

Dave, I compliment you on your professional diligence in keeping such good notes on your work. That's something that I could do well to learn from.

I agree a cement chuck would likely be the best approach to working on an escape wheel. Large ones do exist and they would not be very difficult to make. However, my question referred to TEACLOCKS's clock wheels and not yours because I had already understood your task.

The reason why I asked the question was because clock wheels have been made and repaired for over 500 years. Many of those wheels were also quite large. So the tooling problem has been solved long ago. If we are just doing some regular work on a clock wheel, there should be a way to tackle it without having to resort to having someone make a special tool for us.

Having said that, I have noticed John Wilding just uses 3-jaw chucks to hold his clock wheels (not escape wheels).


Michael

 

[Dave B]

I keep notes for two purposes: first - whenever I have to make up a special tool or jig to do a job, I always draw it first - I had a shop teacher in high school who told me, "If you can't draw it, you probably have not thought it through well enough to make it." I took that to heart, and it has saved me from wasting material and (more importantly, time) on more than one occasion.

The second reason for making notes is they are two kinds of insurance. When a client comes to me and asks why I charged so much to do a job, I can haul out my notes, and overwhelm him with the details of what I did. That is the first kind of insurance. The second kind is being able to refer back to them when I encounter a problem that I know I solved once before. I can look in my notes and see not only what I did the last time, but what I thought I might try different the next time I had to do the same thing.

So really, I keep notes not so much out of discipline as because of that great motivator, fear. LOL

 

[Sterling]

Dave, I just read where you mention in another recent thread in this section that your mentor made you start clock repair using the most basic of tools before you could progress. -And now this, regarding your notes.
I really, really wish I had just 1/10 of your dicipline.

 

[Ansomnia]

I keep notes for two purposes: first - whenever I have to make up a special tool or jig to do a job, I always draw it first - I had a shop teacher in high school who told me, "If you can't draw it, you probably have not thought it through well enough to make it." I took that to heart, and it has saved me from wasting material and (more importantly, time) on more than one occasion. ...So really, I keep notes not so much out of discipline as because of that great motivator, fear. LOL

Dave, you certainly have a great deal of quality work experience under your belt.

Now back to the original question.

I had been wondering about another approach but I am a theorist at the moment as I have no time to actually do much machining if any at all. I was wondering if it would be practical to glue the wheel to a brass or aluminum disc of slightly bigger diameter and then hold the disc with a universal faceplate for turning. This is in effect another form of cement-chucking.

You would need to centre the wheel to the disc when you glue it and it can be done in the following manner:

• first centre the disc against the face plate by locating the centre of the disc. This can be done by measuring its diameter and then locate the centre by scribing across the centre of the disc from 2 or 3 points along its circumference using with the Vernier jaws or a pair of compasses set to the radius of the disc. Where the arcs intercept would be centre.

• punch a mark on the centre and use the mark to align the disc to the faceplate with the pump centre point.

• with the disc centred and secured on the faceplate, drill out a centred hole in the disc to just allow the pump centre to pass cleanly through. The drilling can be made easy if you have an accurately aligned tailstock which can hold drill bits.

• finally, to centre and attach your wheel to the disc you would need to use the cement chuck method of spinning the disc while the wheel is adhering to the disc with glue or molten shellac.

• use a pointed wooden stick (like a pencil or pegwood) and apply light against the hollow centre of the wheel while spinning the assembly and keep the wheel centred until the cement sets.

I think this should work but I've never tried it. I decided to post this suggestion because I just came across a very similar method written up by De Carle to work on barrel covers (page 224 - Practical Watch Repairing, 2005 reprint).


Michael

 

[gvasale]

really basic question: with all the fiddling going on, wouldn't a step chuck really be faster, and of course easier? If I'm not mistaken, the original intent of this question was really with respect to mounted clock wheels, that is wheels and arbors as a unit. Not trying to disparage anyone or a timely and effective idea/method, knowing step chucks and other such useful accessories which I'll not mention right now, stop and think: because I or you have not been exposed to it, is it not a suitable tool? I bet there are loads of watch tools I've never seen, some I HAVE, i DON'T KNOW WHAT THEY ARE! But lets take and scale up to clocks. Isn't it mostly a matter of scale? So some solutions take a few extra $$$, occasionally some fine tuning. Every once and a while you've got to take that bold step, and look a little beyond whats at hand.

I'll give you an example: I'm trying to make 4 bevel gears. Identical. In my small lathe, I try to make a fixture, nothing more than a piece of round stock with a 3/8 -16 threaded hole to mount my blanks. I've got runout, and not sure why. I decide to go upscale and make another "holder" in the big lathe, which will hold a 2 9/16 bar through the spindle. I drill, and tap twice, holding the tap in the tailstock, but I still have runout. (actually, the screw wobbles, like its bent, but 3 different screws shouldn't all be bent.) Solution? Bore the hole for the 3/8 16 screw, instead of drilling and thread with a threading tool, single pointing the thread instead of tapping.
My threading bits came late today, I'll get to it tomorrow. I'll let you know how I make out.

 

[Ansomnia]

really basic question: with all the fiddling going on, wouldn't a step chuck really be faster, and of course easier?.. .

No offense taken but I wasn't trying to "fiddle" or come up with overly elegant and unncessary solutions. As I said, I only posted my suggestion after I realized De Carle also used the same approach.

I actually own several sets of step chucks. But step chucks for watchmakers' lathes are really designed for small wheels and not the larger wheels of many clocks. Many of my clocks' wheels are way bigger than my step chucks and I suspect this is why the original question was posed - he probably could not find a readily-available step chuck big enough for the job.

I asked the original poster, TEACLOCKS, to elaborate on what he needed done on his clock wheels so as to understand the nature and scope of his problem. The drawback to being fixated or already committed to a particular tool approach is that sometimes you are blocking out all other possible solutions - it's always better to focus on and analyse the problem, not the tool. If you only ask a question on step chucks you will only get answers on step chucks, not necessarily the best answer to what you wanted done on your clock.

My idea with using a faceplate is that it can hold bigger wheels than any step chuck on the same lathe. Which I suspect was exactly the reason why De Carle used a very similar approach on page 224 of his book (see my previous reference).

I also mentioned using a 3-jaw chuck which John Wilding uses for clock wheels - but if like in Dave's case you are working on an escape wheel then a 3-jaw chuck might damage such a wheel. However, you can use the method I just suggested and substitute a 3-jaw chuck for the faceplate. The jaws would only mar the disc your wheel is cemented to. This would save you $200 and several weeks of waiting for your chuck to be made. Another good thing is that it will work just as well on a Sherline, which IMO is a better lathe for clock repairs.

Both John Wilding and Donald De Carle are acknowledged to be amongst the best horological experts of their times.

TEACLOCKS did not mention the arbor being integral. But that would definitely pose a problem for a step chuck.


Michael
-> posts merged by system <-

...I'll give you an example: I'm trying to make 4 bevel gears. Identical. In my small lathe, I try to make a fixture, nothing more than a piece of round stock with a 3/8 -16 threaded hole to mount my blanks. I've got runout, and not sure why. I decide to go upscale and make another "holder" in the big lathe, which will hold a 2 9/16 bar through the spindle. I drill, and tap twice, holding the tap in the tailstock, but I still have runout. (actually, the screw wobbles, like its bent, but 3 different screws shouldn't all be bent.) Solution? Bore the hole for the 3/8 16 screw, instead of drilling and thread with a threading tool, single pointing the thread instead of tapping.
My threading bits came late today, I'll get to it tomorrow. I'll let you know how I make out...

gvasale, I'm sure you have a good reason but I would like to understand how your thread-cutting example relates to TEACLOCKS's clock wheel problem. Seems to me you also have an unsolved problem with run-out in your thread-cutting setups or perhaps a problem with your test screws.

At some point, you will still have to figure out why you experienced the unexpected run-out or it will bite you again down the road. So avoiding that task will not be helpful. Are you sure those screws are good? If the holders on the lathes are rigid and your drill bit and tap are straight and rigid, I don't see how you can get a bent thread.


Michael

 

[Dave B]

Actually, my problem was twofold: first, I didn't want to try to grip the outer edges of the escape wheel, as you surmised. Second, it was still on the bent arbor, so I had to have a center clearance hole, to get the wheel flat to turn off the riveted portion on the center boss. I was using a Unimat 3, so I had a conveniently large hole in which to let the arbor extend behind the face plate. (After I got the escape wheel off, and flatened it, it was a simple matter to cut the old arbor off, remove the lantern pinon, and press it onto the new arbor, and put a new bushing in the escape wheel and press it onto the other end..)

 

[Ansomnia]

Actually, my problem was twofold: first, I didn't want to try to grip the outer edges of the escape wheel, as you surmised. Second, it was still on the bent arbor, so I had to have a center clearance hole, to get the wheel flat to turn off the riveted portion on the center boss. I was using a Unimat 3, so I had a conveniently large hole in which to let the arbor extend behind the face plate. (After I got the escape wheel off, and flatened it, it was a simple matter to cut the old arbor off, remove the lantern pinon, and press it onto the new arbor, and put a new bushing in the escape wheel and press it onto the other end..)

Dave, thanks for elaborating on the full issues posed by your escapewheel problem.

Actually, I suspect your solution and Smudgy's are both probably very close to how the original clockmakers did it on the old lathes. I think your methods would be perfectly suitable as standard clock repair procedures.


Michael

 

[TEACLOCKS]

TEACLOCKS, I'm going to come back to your original question.

I'm curious and would like to ask why you need step collets for clock wheels. What are you trying to do with the clock wheels?


Michael

Im looking for an easy way to hold wheels for polishing that one end of the arbor is short with just the pivot sticking out.
and need to polish the long end.

 

[Dushan Grujich]

Im looking for an easy way to hold wheels for polishing that one end of the arbor is short with just the pivot sticking out.
and need to polish the long end.

Good Day Teaclocks,

You do not need large step chucks to achieve that.

Have a look at the image bellow and if You need more info, follow the link click here and click here



Instead of a large step chuck there is a female centre with driver mounted in headstock and the tailstock holds Jacot drum and pivot that is being worked on.

You can get all the equipment needed on eBay for the price of one new large step chuck.

Cheers

Dushan

 

[Ansomnia]

Im looking for an easy way to hold wheels for polishing that one end of the arbor is short with just the pivot sticking out.
and need to polish the long end.

It looks like you just need a clock pivot polisher.

Dushan is showing one of the appropriate clock pivot polishing setups. It may also be a good idea to use hand power and this can be done with a bow wrapped over a ferrule which is fastened to the long end of the wheel arbor.

A custom step collet would cost a lot more than such a simple polisher and would only be good for certain size(s) of wheels.

I think unless one is already very familiar with all the watchmaker's tools, it's better to just focus on the problem and what you need to do rather than to assume a certain, perhaps unfamiliar tool, is what you need. This is particularly advisable when asking questions on a MB - because you can only write so much; best to focus on the most essential aspects of your inquiry. Anyway, I think most people would consider tools to be less essential than proper technique.


Michael

 

[TEACLOCKS]

It looks like you just need a clock pivot polisher.

Dushan is showing one of the appropriate clock pivot polishing setups. It may also be a good idea to use hand power and this can be done with a bow wrapped over a ferrule which is fastened to the long end of the wheel arbor.

A custom step collet would cost a lot more than such a simple polisher and would only be good for certain size(s) of wheels.

I think unless one is already very familiar with all the watchmaker's tools, it's better to just focus on the problem and what you need to do rather than to assume a certain, perhaps unfamiliar tool, is what you need. This is particularly advisable when asking questions on a MB - because you can only write so much; best to focus on the most essential aspects of your inquiry. Anyway, I think most people would consider tools to be less essential than proper technique.


Michael

In all my trades Iv usually had less tools than most, And done more and better work with them than the others.

 

[Ansomnia]

In all my trades Iv usually had less tools than most, And done more and better work with them than the others.

Yes, I can certainly believe that. Good workmanship beats neat tools any day!

As for me, I must confess I have actually been a tool-collecting addict myself. My saving grace was that I only collected the tools that I need to use.


Michael

 

[Dushan Grujich]

In all my trades Iv usually had less tools than most, And done more and better work with them than the others.

Good Day Teaclocks,

I am not sure that I understand your comment.

Do we have to feel guilt, for knowing which tools we need and then again for buying and using them?

After all, it was You who asked for help, we have only tried to oblige.

If I am wrong, please correct me.

Cheers

Dushan

 

[TEACLOCKS]

Good Day Teaclocks,

I am not sure that I understand your comment.

Do we have to feel guilt, for knowing which tools we need and then again for buying and using them?

After all, it was You who asked for help, we have only tried to oblige.

If I am wrong, please correct me.

Cheers

Dushan

Your right Im the one that asked.

 

[Dave B]

Yes, I can certainly believe that. Good workmanship beats neat tools any day!

Many years ago, I was told that a good workman can do excellent work with the poorest of tools. (Actually it was a good musician can make any instrument sound good) That may be true, but I can say from experience that those of us who are merely mediocre need all the help we can get, and good tools go a long way in that direction.

 

[TEACLOCKS]

Good Day Teaclocks,

You do not need large step chucks to achieve that.

Have a look at the image bellow and if You need more info, follow the link click here and click here



Instead of a large step chuck there is a female centre with driver mounted in headstock and the tailstock holds Jacot drum and pivot that is being worked on.

You can get all the equipment needed on eBay for the price of one new large step chuck.

Cheers

Dushan

In your picture there is 3 or 4 pieces to polish with, and a lot of set up time.
There would only be 1 step collet.
Thank you very much for the input.

 

[Dushan Grujich]

In your picture there is 3 or 4 pieces to polish with, and a lot of set up time.
There would only be 1 step collet.
Thank you very much for the input.

Teaclocks,

The set-up on that image is really for pivot burnishing, not for polishing. Polishing pivots is cosmetics makes pivot shiny, more or less, while burnishing is a process of work hardening the pivot surface and is desired end result. Therefore the need for Jacot drum, which serves as a firm support, to allow pressure to be exerted upon the burnisher and transferred to pivot surface.

I agree with You that a step chuck would be only one piece and that it would be faster to set up, however one cannot accomplish burnishing (work hardening) of pivots without some sort of support.

If You do not mind, I would suggest to You to download and read couple of articles on pivot preparation done by Bob Whiteman. Also an article by David LaBounty describing and explaining process of burnishing. Articles will give You an in depth understanding of differences between pivot burnishing as opposed to pivot polishing.

Whiteman's Pivot Analysis 1

Whiteman's Pivot Analysis 2

Burnishing

Strangely enough pivot polishing seems to be practice peculiar to majority of American clock repairers, while European (as well as UK) clock repairers burnish pivots.

Of course it is upon one's own self to decide which method is more suitable and is better serving pivots of the clock being serviced.

Cheers

Dushan

 

[Ansomnia]

Teaclocks, a step chuck is not a good tool to polish or burnish a pivot with. The step chuck is designed to support the wheel and for you to work on the wheel. Actually, cement chucks are safer and more accurate than step chucks in that regard but the step chuck is easier to set up and does not require a sometimes bothersome cleanup to remove the shellac.

Holding a wheel by its teeth does not guarantee concentricity with the pivot. The wheel would also have to be absolutely flat, with no dishing or no high spots on the teeth. You must also make sure the wheel is held perfectly flat against the chuck. The hold from a step chuck is not very strong and is arguably grabbing onto a potentially sensitive portion of the wheel. And at the end of all that you would still need to support the pivot to burnish it. As Dushan and many others before have tried to stress, just polishing the pivot is not enough. Polishing will remove the rough spots but the metal will remain soft and will charge up with dirt and become a "sanding drum" soon after it goes back to service. To harden the pivot you need to burnish it and supporting the pivot is a good way to set up for burnishing because you have to apply pressure on the pivot when burnishing.

The assembly shown by Dushan only takes a couple of minutes to set up and you would be holding onto a safe part of the wheel and guaranteeing concentricity. You will also have a pivot holder for burnishing.

I think an important aspect of watch- and clockmaking tools and techniques to consider is that vintage mechanical clocks and watches involve old established and unchangeable designs. They are "antiques". They are not new. You are not working on some revolutionary new mechanical designs that require equally new servicing approaches. So all of the techniques and tools to service them have already been well worked out by people with knowledge and skills that far surpass us. We have almost no chance of doing a better job than the masters who came before us. All we can add is automation which by definition is bad for many of the old clocks and watches - because many were made by hand. Hand-made items require hand skills for servicing.

Anyway, I am starting to digress but I think this is an important point to stress. When you enroll in a watch- or clockmaking school they will teach you established tecnhiques; they won't teach you how to conduct research on new techniques.


Michael

 

[Dave B]

Gripping a wheel in order to do arbor or pivot work is an almost sure way to warp the wheel. The force imparted to the wheel through it's center bushing is teh force exerted on the end of the pivot or arbor, multiplied by a trigonmetric function of the distance from the center of the wheel. So what seems to be a very slight pressure on the end of an unsupported arbor may easily multiply to a foot pound or more at the center.

 

[TEACLOCKS]

What about a Bezel chuck ? Holding the wheel.