Minimalist bushing and polishing tool set

[murphyfields]

I have been listening to the advice I have been given here, and have decided to try learning to redo bushings and polish pivots on several Hermle movements. I have been reading many discussions of bushings, but there are so many here that it is a bit overwhelming knowing where to start. My budget is limited, so I will be starting out with sub-optimal tools, but many here claim to do just fine with a few basics. So what is the minimum required for an acceptable job of rebushing and polishing (doing the job for myself, so it does not have to look professional, but I would like to have a good chance of it working for a while after I am done)? There is a good chance that I will disassemble and reassemble them several times, so I don't mind fiddling. I will start with pivots that are obviously worn, see what happens, then maybe move on to ones that have lesser wear. I have not yet decided on traditional bushings or butterbearings, so would like to be able to do either

I will be working on Hermle 1050 series or 1150 series movements. I can let down the springs. I have a small drill press and basic bits , but no needle files, no broaches, no reamers, and only basic hammers. I have some simple calipers good to around 0.01". So given my limited budget (maybe $100, up to $200 if things are significant must-haves) what else is absolutely vital? How about really useful? If you had to start all over from scratch, what would you buy?

How do I know what bushings I need?

Thank you all for your help.

 

[brian fisher]

i don't think it will be easy to acquire a decent set of repair tools within your budget. it is good that you have a drill press. i started cutting bushing holes that way. i would concentrate on the kwm system. there is an adapter for your drill press that will accept the reamers. start out with about 2 or 3 reamers of the size you will need to replace your first bushings. get the centering tool that they make. basically a long skinny cone that slots into the adapter. asian files and other tools are very cheap at timesavers and harbor freight. i would start with those and upgrade as your needs require.

 

[TooManyClocks]

I went to Ronell Clock when first starting out, and got their TL-41 broach set https://www.ronellclock.com/searchquick-submit.sc?keywords=Tl-41
and a KWM hand bushing tool set TR-38 (the handle and reamers can be bought separately if you know you will only be working with a few bushing outside diameters, and you can buy other sizes as the need arises) https://www.ronellclock.com/searchquick-submit.sc?keywords=TR-38. This assumes you will be using KWM bushings; Bergeon bushing tools can be bought instead.

After trying several needle files and being unhappy with all of them, I got a Grobet escapement file and found what i needed. A little pricey for one file, but definitely worth it in my opinion Grobet Swiss Pattern File Escapement 5-1/2" Round Cut 6 - Swiss Pattern Files - Amazon.com

I don’t work on Hermle movements, so I can’t advise what size bushings are appropriate, and the appropriate tools for pivot polishing on a Hermle arbor are best advised by someone else, as they are another critter entirely from what I work on. Plated pivots aren’t my thing...

I also bought a smoothing broach set that never gets used as I’m not convinced it accomplishes anything, so if anyone wants the set for the cost of shipping, send me a PM.

Hope this helps

John

Edit: Actually, if anyone wants the smoothing broach set, forget the shipping charge. I think I paid $35 for them, so it’s not an expensive set, but they are certainly adequate. Free to anyone who needs them. I’d rather they get used, and they’re not needed here.

 

[kinsler33]

Timesavers' inexpensive cutting broaches are a good deal, and you'll need a couple of pin vises to use them with. Don't buy broaches with handles. You'll need #2, #3, and #4 KWM reamers. Buy the handle, too, but since it's pretty overpriced deal with it later. The drill press adapter for the reamers isn't mandatory: I just chuck the reamers right into the drill press.

Recommendations:

Rotary Tool Kit, 80 Pc. (excellent rotary tool for lots of things)

10-Piece Diamond Reamer Set Use these in the rotary tool above. They make excellent pivot files. You can use them by hand, too.

10-Piece Cutting Broach Set .027" - .088" About as good as the Bergeon set I inherited.

American Pattern Pin Vise You can never have enough pin vises, but buy a couple of these to start with.

8" Pivot Locator I hate this thing for reasons I cannot explain, but it's really helpful when you're assembling the movement.

Get screwdrivers, pliers, and files at Harbor Freight or your favorite Walmart store. (Note that Walmart has become really serious about tools.) The tiny files from Harbor Freight are pretty good.

Hand Reamer KWM Style Handle Only Not really worth it, but you might as well get it with size II, III, and IV KWM reamers

I keep a stock of KWM-sized bronze bushings (brass is fine too) in sizes 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, and so on all the way up to 1.9mm. I never had luck with the pre-made bushing assortments. The tiny bushings are used a lot with KWM's upper trains.

Clock oil: Mobil1 0W-20, available at Walmart in several styles, any of which work fine. One quart will last the rest of your life.

Clock grease can be anything you'd use in a car, but don't use black because it's a mess. The red stuff or amber is fine and really hangs in there. For light grease, use white lithium.

Mark Kinsler

M Kinsler

 

[TooManyClocks]

Yeah, Mark’s right. I forgot about the pin vises...you’ll need them. The broaches recommended earlier do need pin vises. There is one set of larger broaches with handles around here, and they are a total pain to even try to work with. I need to get those handles off and rework them for a pin vise or something before a need comes to rebush a mainspring pivot hole with them again. They’ve been sitting in a corner, forgotten until now.

I haven’t been working on clocks for some months until the weather gets lousy enough to keep me inside, then I’ll start up again. In the meantime, it’s easy to forget important stuff like a pin vise

John

 

[kinsler33]

Good luck getting those black plastic handles off, even if they're broken or slipping. I finally had to place the handle of a big cutting broach on an anvil and beat the thing with a hammer. Behold: underneath was a crooked, distorted steel shaft, yechh. So now I use that broach and others with those handles with the ultimate pin vise: i.e., a half-inch Jacobs chuck (with key) purchased at Harbor Freight Tools for a modest sum. The chuck isn't mounted on anything--I just use it as a handle, and it works nicely. Beats the heck out of any ultra-large-capacity pin vise for the purpose. The one Timesavers sells is relatively horrible, though I still use it on occasion.

Mark Kinsler

 

[TooManyClocks]

Well, now I know what i‘m in for with the things—thanks for the idea of how to deal with them!
There’s an old Milwaukee 1/2 inch broken drill around here I’ve never used or needed but always planned to get around to fixing, but since I never needed it, there it sits. Robbing the chuck off that and putting it to use as needed on those cutting broaches sounds like a good use for that situation—and if the drill is ever needed (unlikely 10+ years later) the chuck can just go back on

John

...and our missing posts reappeared!

 

[wow]

Murphy, Butterworths sells polishing discs that work well. They will work in a Dremel, lathe, or drill. There are three grades of coarseness. They are very inexpensive. Buy more of the middle grade than the other two.

 

[shutterbug]

Keep in mind that some suppliers have a minimum order that must be met or additional charges will be added to your order. Some also automatically add insurance charges unless instructed not to. It seems silly to insure a box full of unbreakable things. So when ordering, it's cheaper in the long run to order several things together, and specify no insurance in the box for specific instructions.

 

[kinsler33]

Timesavers adds the insurance in case the stuff is lost, not broken. I think. The under-$20.00-charge is, I think, $7.00. Bear in mind that while Timesavers people are exceptionally efficient and courteous, they don't know a lot about clock repair. It's easier to use the paper catalog (despite its rotten index) than the on-line catalog, but both are really necessary. The on-line listings for discontinued/surplus/whatever merchandise can be a real time sink, but lots of fun, and there are bargains to be had. (Set number of items per page to 96, then use your 'page down' key to scroll.)

I also like Ronnell clock co., which features a lively paper catalog with lots of weird quartz movements as well as mechanical stuff. They're also quite efficient and faster than Timesavers, which isn't great in the speed category. Still, I order most stuff from TS.

Mark Kinsler

 

[murphyfields]

Thank you all for your suggestions. There are many things on these lists that I would never have thought of (like those pin vices and the escapement file), and I would not have thought about the minimum orders or insurance issues.

I should probably add that I have found a wonderful source for clock tools and supplies a short drive away at Mile Hi Clock Supplies in Broomfield, Colorado, and the owner has been great to work with, and I am sure I will be getting to know him better over the next several months. The web site is pretty minimalist, but the prices seem very competitive compared to what I see on other sites, plus I have no shipping charges other than the price of gas to get there and back.

I am still hoping to hear some suggestions from bangster since he seems to be one of the biggest supporters of rebushing with hand tools. But all of these suggestions are extremely helpful.

As I understand things (and this is really fuzzy in my brain) I could use either reamers or broaches for enlarging the holes for the bushings. If I use reamers, I would need one for each size (OD) of bushing I might use, but if I use broaches, I might be able to cover several sizes with a single broach, but I really risk making the final hole a little too big unless I am very careful. And in general, I am better off using both a broach and a reamer than using just one. Is this anywhere close to correct?

When using a broach and/or reamer, is it better to turn them under power in a drill press, turn a drill press by hand, or do the whole thing by hand?

 

[TooManyClocks]

Use reamers to enlarge the hole for bushing installation. The bushings are an interference fit of about an thousands or so, and i can’t foresee success using a broach and kind of accidentally landing on the precise hole size to assure a press fit for the bushing.

It is important when using a reamer to stop immediately when the reamer finishes the hole cut. Continuing to turn after the hole is cut through tends to enlarge the hole beyond what is desired, and the bushing will likely fit too loosely and/or fall out.

Ream out the hole by hand or using a bushing machine (or a drill press that doesn’t have any runout) install the bushing, then broach out the ID of the bushing to fit the pivot. That’s how I do it anyway.

If I used a drill press to install bushings (I haven’t), it would be best to turn it by hand.

John

Edit: Practice on a junk movement plate first!

 

[roughbarked]

Thank you all for your suggestions. There are many things on these lists that I would never have thought of (like those pin vices and the escapement file), and I would not have thought about the minimum orders or insurance issues.

I should probably add that I have found a wonderful source for clock tools and supplies a short drive away at Mile Hi Clock Supplies in Broomfield, Colorado, and the owner has been great to work with, and I am sure I will be getting to know him better over the next several months. The web site is pretty minimalist, but the prices seem very competitive compared to what I see on other sites, plus I have no shipping charges other than the price of gas to get there and back.

I am still hoping to hear some suggestions from bangster since he seems to be one of the biggest supporters of rebushing with hand tools. But all of these suggestions are extremely helpful.

As I understand things (and this is really fuzzy in my brain) I could use either reamers or broaches for enlarging the holes for the bushings. If I use reamers, I would need one for each size (OD) of bushing I might use, but if I use broaches, I might be able to cover several sizes with a single broach, but I really risk making the final hole a little too big unless I am very careful. And in general, I am better off using both a broach and a reamer than using just one. Is this anywhere close to correct?

When using a broach and/or reamer, is it better to turn them under power in a drill press, turn a drill press by hand, or do the whole thing by hand?

If you start doing it by hand, you should finish by hand.

 

[kinsler33]

As I understand things (and this is really fuzzy in my brain) I could use either reamers or broaches for enlarging the holes for the bushings. If I use reamers, I would need one for each size (OD) of bushing I might use, but if I use broaches, I might be able to cover several sizes with a single broach, but I really risk making the final hole a little too big unless I am very careful. And in general, I am better off using both a broach and a reamer than using just one. Is this anywhere close to correct?

When using a broach and/or reamer, is it better to turn them under power in a drill press, turn a drill press by hand, or do the whole thing by hand?

With the KWM system you really only need three sizes of reamers anyway. Add the handle and you're set to do bushing by hand, which was how the scheme was envisioned when I first saw it around 1964. Having said that, surprise: you can actually use tapered cutting broaches for any sort of press-in bushings. Yes, the hole will be tapered, but since the plates are so thin relative to the length of the broach, the taper is actually negligible and the bushing will push in and remain there quite nicely. And since you're dealing with brass, a hole that's too big isn't much of a tragedy because you can enlarge the bushing's diameter by placing it on an anvil and giving it a whack with Mr Hammer, or do the same with a round nosed punch near the edges of the hole, which makes the hole smaller. Most of the time it's not a bad idea to lock the bushing into the plate with a bit of red Loctite.

I use my drill press with a KWM reamer chucked directly into it, and under power. Buy yourself a collection of PVC pipe couplers at the plumbing department and lay your clock plate on one of those whilst reaming. For any other broaching I turn them by hand: I've made wooden handles for my small broaches out of those pre-made dowels used by woodworkers; Harbor Freight has them.

Do a YouTube search for Mark Butterworth and look at his bushing video. That's how I do it.

Oh: pushing bushings into their holes can be interesting. I have a pair of very small welding-clamp pliers from Harbor Freight that works well for bushings in the middle of a plate, and for those closer to the edge you can't do much better than a pair of smooth-jawed, parallel-jaw pliers. I got a made-in-Pakistan pair through eBay, and they've turned out to be indestructible, though they appreciate being oiled occasionally.

Mark Kinsler

 

[shutterbug]

Keep in mind that using a broach creates a tapered hole. It's not a huge issue, but brass compresses easily and when you push your bushing in, it's usually the bushing that will give. That reduces your ID measurement, which might then need to be broached too, making another tapered hole. Clocks can be very forgiving, but the more precautions you take in the learning process, the fewer bad habits you have to deal with later

 

[murphyfields]

I use my drill press with a KWM reamer chucked directly into it, and under power. Buy yourself a collection of PVC pipe couplers at the plumbing department and lay your clock plate on one of those whilst reaming.

I see you use an approach that some here might consider a little "loose" but seems to work well for you. I don't have enough personal experience to judge, but I have known machinists that have been able to work miracles with hand and eye. To me, this implies that either the movements are far more forgiving than I would have thought, or you have incredibly skilled hands, or you are incredibly lucky. How often do you have to redo a bushing where the spacing far enough off to affect the operation of the movement? If not often, what do you attribute your success to?

Doesn't the KWM system have a pin in the shaft that interferes with the drill chuck?

Clocks can be very forgiving, but the more precautions you take in the learning process, the fewer bad habits you have to deal with later

That is why I am asking many many questions here before I start trying this myself. What always puzzles me is that there seem to be several successful people with bad habits. Does that mean the habits are really not that bad, or that failure has weeded out the really bad ones, leaving the lucky and the miracle workers?

That reduces your ID measurement, which might then need to be broached too, making another tapered hole.

I thought that was part of the correct procedure...use a bushing with an ID that is slightly too small, then broach to fit. Is there another way to do this?

 

[wow]

Murphy, I do not use the broaching method for the ID. Like Shutt said, broaches are tapered and the hole you broach will be tapered. I choose a bushing whose ID fits the polished pivot with a little slack. The arbor should wobble about 5% after installed. Occasionally I have to broach slightly (from both sides to keep the hole untapered), but most of the time I just pop in the bushing, check it with the polished pivot, camphor the inside edge, and it’s done. Since bushings come with perfectly straight IDs, why not use them as is?

 

[murphyfields]

Murphy, I do not use the broaching method for the ID. Like Shutt said, broaches are tapered and the hole you broach will be tapered. I choose a bushing whose ID fits the polished pivot with a little slack. The arbor should wobble about 5% after installed. Occasionally I have to broach slightly (from both sides to keep the hole untapered), but most of the time I just pop in the bushing, check it with the polished pivot, camphor the inside edge, and it’s done. Since bushings come with perfectly straight IDs, why not use them as is?

Does this imply a particular brand of bushing, or can you get a perfect fit using any of the systems? Do you measure the pivot then choose the appropriate bushing, or do you just try several and use the one that fits best? I suppose your approach means you need to keep a wide range of sizes on hand, versus a broach method.

(I apologize for all my questions here...this is a whole new world for me, and I figure bushings are the things I am most likely to mess up. My username is murphyfields because I have had many unusual things go wrong...nothing terrible, but usually entertaining, at least for some.)

 

[kinsler33]

I almost always use the KWM reamers, which give a straight-sided hole. And the bushings still compress, and thus have to be broached out a bit, which leaves a tapered hole. You're welcome to compute the amount of taper, but you'll find it's infinitesimal, and you do _not_ want a closely-bushed pivot hole anywhere, anyway.

Bushing OD's aren't generally very accurate, which means that some will be miserable to push in and others will fall right out, regardless of brand. Bushing ID's probably are no better, but can be adjusted with a broach.

You can size bushings by just trying successive ones on your pivot (this works fairly well with experience.) But I've begun measuring pivot sizes with calipers (digital is fine, but I like the metric dial caliper I bought.) I generally lay the wheels from each train out in an ice-cube tray and measure each of the pivots in succession. Bushings for a wheel go in the ice-cube compartment for that wheel. Then I'll ream out all the holes needed for that train on the drill press and push the appropriate bushings in for each hole.;

After the bushings for each wheel are installed I put the plates together with only that one wheel to make sure it spins freely and maybe rattles a bit. Bushing a clock too tightly is a very bad idea, and it's tempting to do because you want the pivots to be accurate. But they shouldn't be, for when the clock is assembled and wound, the plates distort somewhat from the torque of the mainsprings or the pull of the weights, which pulls the pivot holes out of line. If they're too tight, the clock will stop.

The pin on KWM reamers won't interfere with the drill chuck. The problem with the adapter is that the reamer can fall out, and if your place is a wreck like mine, that's not desirable

Mark Kinsler

 

[wow]

Mark explains it well. The only thing I can add is that I use a KWM pivot guage which gives me a chance to insert the pivot into a plate and check the tilt. I choose a bushing that allows about 5% tilt. Then the same size bushing inserted in the clock plate will fit the pivot. Bergeron bushings have larger ODs which sometimes causes problems if the hole is near the edge of the plate or in a tight spot.

 

[TooManyClocks]

Find a junk movement, or buy the cheapest random movement you can find on ebay or elsewhere that at least resembles what you’ll be working on, and practice on it. A lot of your uncertainty, questions, what-ifs, etc. will be helped by diving in and doing it. You should do that anyway before jumping in on a clock movement you care about so you don’t potentially make several mistakes on it.

Practicing on a few pivot holes on a junk movement taught me a lot the first time around. Good luck—you can’t do worse than me, and all my clocks still run just fine, including the first ones I worked on.

.Here’s a photo of the first clock I ever worked on. It’s running right now in my living room. With few exceptions, it’s run pretty much 24/7 since I overhauled it, although it’s been hung in various locations around the house. It’s a New Haven Saturn spring driven model. I think they were more commonly sold as a weight driven clock to compete with Seth Thomas #2.



John

Edit: if you can’t find a cheap junk movement, PM me, and I’ll send you something out of my pile

 

[D.th.munroe]

Mark.
I don't like those pivot locators either. (I was told they were originally typewriter spring tools)
I use long pickling tweezers, and for smaller clocks regular stiff tweezers with notches in the tips, gives more control.
Dan.

 

[Schatznut]

"What always puzzles me is that there seem to be several successful people with bad habits. Does that mean the habits are really not that bad, or that failure has weeded out the really bad ones, leaving the lucky and the miracle workers?"

I'm still a relative newbie at clock repair and I understand what you're saying. What I've learned is, just as there are many ways to screw up the repair of a clock, there are (not quite as) many ways to do it successfully. So if what you try works and the clock is still running a few years later, who can tell you your technique was bad?

I try to adopt the Hippocratic Oath: "Above all, do no harm," and endeavor to retain as much of the original clock as possible. I've got a couple that I've not repaired successfully yet, but I keep at them. I learn more from the things I tried that failed than I do from the ones that succeeded.

 

[roughbarked]

"What always puzzles me is that there seem to be several successful people with bad habits. Does that mean the habits are really not that bad, or that failure has weeded out the really bad ones, leaving the lucky and the miracle workers?"

I'm still a relative newbie at clock repair and I understand what you're saying. What I've learned is, just as there are many ways to screw up the repair of a clock, there are (not quite as) many ways to do it successfully. So if what you try works and the clock is still running a few years later, who can tell you your technique was bad?

I try to adopt the Hippocratic Oath: "Above all, do no harm," and endeavor to retain as much of the original clock as possible. I've got a couple that I've not repaired successfully yet, but I keep at them. I learn more from the things I tried that failed than I do from the ones that succeeded.

The clock was designed and built to work. The general rule is don't change anything but learn how beautiful it is.
Once you know that you may try to put some things back the way they were.
Luck and miracles don't fix clocks.
If you write everything that you notice down. Then you write everything you change down. You have a control and a comparison.

 

[bangster]

Have you looked at Bushing Using Hand Tools?

 

[murphyfields]

Have you looked at Bushing Using Hand Tools?

I have, but it appears that a number of the pictures did not survive the update.

Some questions I have specifically for bangster but open to all for comments...If you were only going to work on basic Hermle movements, what would you use. What are good needle files for "recentering" the holes. Would you use KWM or Bergeon tools and bushings? Are there sizes of reamers and broaches that are most commonly used, especially on Hermles?

 

[bangster]

I'll get back to you on that. Right now I have to go check on the article.

 

[TooManyClocks]

I'll get back to you on that. Right now I have to go check on the article.

the Beat Setting 101 article seems to have the same problem as well. Images are missing

John

 

[kinsler33]

I have, but it appears that a number of the pictures did not survive the update.

Some questions I have specifically for bangster but open to all for comments...If you were only going to work on basic Hermle movements, what would you use. What are good needle files for "recentering" the holes. Would you use KWM or Bergeon tools and bushings? Are there sizes of reamers and broaches that are most commonly used, especially on Hermles?

From post #4:
10-Piece Diamond Reamer Set Use these in the rotary tool above. They make excellent pivot files. You can use them by hand, too

Hermles have tiny thin pivots, so you generally need sub-1mm bushings for the upper trains and escapement. See post #4.

Mark Kinsler

 

[murphyfields]

From post #4:
10-Piece Diamond Reamer Set Use these in the rotary tool above. They make excellent pivot files. You can use them by hand, too

Hermles have tiny thin pivots, so you generally need sub-1mm bushings for the upper trains and escapement. See post #4.

Mark Kinsler

kinsler33 those are on my list. I am just trying to figure out how everything works together. Everyone has their own procedures. Are these reamers like the KWM or Bergeon that create a precise size of hole, or more like a tapered reamer? From the image on timesavers, they look tapered. And do you use them to create a slot opposite the one created by wear, a la bangster 's hand tool method, or do you have your own method?

 

[kinsler33]

1) clean everything

2) polish all pivots

3) rebuild time train between the plates, typically minus the verge

4) rock the train back and forth to find the worst holes

5) rock the train in the direction opposite that which it goes when the clock is running and mark the side of the ovalled hole where its respective pivot rests

6) using your best judgement, use a 'diamond reamer' to file out the marked side of the hole so as to render the oval symmetrical with the pivot's original location. You can use the rotary tool suggested or (at first) just hold the 'reamer' by hand and file out the hole. The diamond cuts fast.

7) ream out the filed hole with a bushing reamer or, rarely, a tapered cutting broach. The tool will center itself in the symmetrically-filed hole and thus bore a hole that's concentric with the original pivot location.

8) Use a countersink to de-burr both sides of the newly-reamed hole

9) push in the bushing with the 'oil sink' toward the outside of the plate

10) repeat for the other pivot of that wheel and then assemble the plates with only that particular wheel between them. The wheel should spin freely with the plates held in any position. If the wheel doesn't like to turn, gently remove a couple thousandths of an inch from the ID of the bushing with a tapered cutting broach. Test the wheel with the front plate underneath, and then with the back plate underneath. If the wheel hesitates, the bushing in the 'underneath' plate needs to be enlarged the slightest bit.

11) then go to the next wheel until you're done.

12) repeat the procedure for the other wheels in the other trains.

 

[murphyfields]

1) clean everything

2) polish all pivots

3) rebuild time train between the plates, typically minus the verge

4) rock the train back and forth to find the worst holes

5) rock the train in the direction opposite that which it goes when the clock is running and mark the side of the ovalled hole where its respective pivot rests

6) using your best judgement, use a 'diamond reamer' to file out the marked side of the hole so as to render the oval symmetrical with the pivot's original location. You can use the rotary tool suggested or (at first) just hold the 'reamer' by hand and file out the hole. The diamond cuts fast.

7) ream out the filed hole with a bushing reamer or, rarely, a tapered cutting broach. The tool will center itself in the symmetrically-filed hole and thus bore a hole that's concentric with the original pivot location.

8) Use a countersink to de-burr both sides of the newly-reamed hole

9) push in the bushing with the 'oil sink' toward the outside of the plate

10) repeat for the other pivot of that wheel and then assemble the plates with only that particular wheel between them. The wheel should spin freely with the plates held in any position. If the wheel doesn't like to turn, gently remove a couple thousandths of an inch from the ID of the bushing with a tapered cutting broach. Test the wheel with the front plate underneath, and then with the back plate underneath. If the wheel hesitates, the bushing in the 'underneath' plate needs to be enlarged the slightest bit.

11) then go to the next wheel until you're done.

12) repeat the procedure for the other wheels in the other trains.

Thank you, thank you. This is incredibly helpful. Once I am done with my first few movements I will try to write up what I learned to help other newbies, with generous quoting of your suggestions.

A few more questions before I place my first order for tools...

What do you use for polishing the pivots? Both in general and with plated pivots specifically? Do you also use Butterworth's polishing disks?

Do you use anything to smooth or burnish the bushings once you are done installing and sizing?

Are the diamond reamers designed to be used in only a rotary motion, or do they also cut in a reciprocating motion?

 

[kinsler33]

Thank you, thank you. This is incredibly helpful. Once I am done with my first few movements I will try to write up what I learned to help other newbies, with generous quoting of your suggestions.

A few more questions before I place my first order for tools...

What do you use for polishing the pivots? Both in general and with plated pivots specifically? Do you also use Butterworth's polishing disks?

Do you use anything to smooth or burnish the bushings once you are done installing and sizing?

Are the diamond reamers designed to be used in only a rotary motion, or do they also cut in a reciprocating motion?

I've been using Timesavers' 'emery buffs,' grits 1/0 to 6/0. I ought to make my own, but I'm lazy and I seem to use the spent sticks for all sorts of other projects.

Emery Buff - #2/0

#2/0 emery buff is 10" long and 7/8" wide. Made in India. Combine with other sizes for price break.

timesavers.com

The 6/0 buff polishes the pivots better than anything else I've seen. What I generally do about the holes, either directly in the plates or through bushings, is nothing. I've read plenty about work-hardening the inner walls, smoothing the walls, and all the rest, but I've yet to see any benefit to smooth-broaching the walls. I used to do it, but I sort of gave up.
They work splendidly in linear motion as well as rotary motion. If they prove difficult to grip you can grab them in a pin vise. Again, the diamond cuts brass very quickly, so watch it. The files taper down to a very fine point, which sometimes will break off, but that hurts nothing except your ability to file the very smallest holes.

I think I'll try designing a mainspring winder sometime. One of those ratcheting box wrenches would work well for the ratchety part, and the rest wouldn't be all that diffic

 

[murphyfields]

I'll get back to you on that. Right now I have to go check on the article.

bangster it is good to see that the pictures are back up. Those are very helpful.

 

[murphyfields]

From Post #4

10-Piece Cutting Broach Set .027" - .088" About as good as the Bergeon set I inherited.

It looks like I may need to rebush some large pivots. The minute hand arbor and the arbor for one of the weights appear to have worn pivot holes. The pivots are around 2.8 or 2.9 mm. Would I be better off with a single cutting broach (and if so, what size), or this set

10-Piece Cutting Broach Set For Alarm Clocks .027" - .141"

or maybe

10-Piece Cutting Broach Set For Large Clocks .035" - .157"

instead or in addition to the one suggested above?

 

[howtorepairpendulumclocks]

just a thought here... yes you will have at some point to bush holes and there is a lot of advice above how to do it which is great! I see you refer to large pivot holes needing re-bushing. Have you checked depthing first to confirm they need attention? I think you will find, once you have checked depthing, surprisingly few bushes need replacing. Same goes for pivot polishing. I know some modern clocks have chrome plated arbors and when this begins to break down, it causes a major problem. In my experience, regular steel pivots need very little polishing. Most grooves or mark run around the circumference of a pivot, in the direction of rotation, not along its length. Yes, through washing of the movement, pegging out and re-lubrication are important (critical in fact), but it may just be worth considering and experimenting with bushing only where it will result in a tangible improvement in depthing. Sorry to join the thread so late. Hope this helps.

 

[roughbarked]

just a thought here... yes you will have at some point to bush holes and there is a lot of advice above how to do it which is great! I see you refer to large pivot holes needing re-bushing. Have you checked depthing first to confirm they need attention? I think you will find, once you have checked depthing, surprisingly few bushes need replacing. Same goes for pivot polishing. I know some modern clocks have chrome plated arbors and when this begins to break down, it causes a major problem. In my experience, regular steel pivots need very little polishing. Most grooves or mark run around the circumference of a pivot, in the direction of rotation, not along its length. Yes, through washing of the movement, pegging out and re-lubrication are important (critical in fact), but it may just be worth considering and experimenting with bushing only where it will result in a tangible improvement in depthing. Sorry to join the thread so late. Hope this helps.

Riveting or mushrooming of pivots is basically caused by these rotational groovings. How do you account for not touching these pivots?

 

[howtorepairpendulumclocks]

I would say the pivot cannot ever be larger than the hole in which it fits. Yes, wear can accumulate to the point where the pivot appears 'mushroomed'. Yes I know it is considered by some for the default to leave 'sloppy' pivots as bad practice. What I would say, is "will the re-finishing of this pivot or re-bushing this hole improve depthing and therefore the operation of the clock?". If the answer is unequivocally YES, then of course, some intervention is needed. Otherwise, personally I would struggle to be able to justify intervention. I understand this subject can get people hot under the collar but I scanned that long thread of helpful responses and didn't see one person advising a minimal intervention approach.

 

[roughbarked]

It is OK. I'm not going to damn you to burn for your crimes.
There is enough evidence to say that a clock will often run again if cleaned and oiled in the Duncan Swish method.
I'd still like to know what you have to say about the relationship of such mushroomed pivots to depthing.

 

[howtorepairpendulumclocks]

.. ) The answer is to always check depthing before pivot-polishing or re-pivoting or bushing before intervention. If you can happily say "yes, the depthing will be improved by bushing/polishing/re-pivotting", there of course, no problem. My two-pennethworth is that much bushing / re-polishing is unnecessary for the improved operation of the clock. Yes, the pivots sometimes wear to the degree that they almost wear through and are unsafe, then of course, you consider re-pivotting. PS Checking depthing in the frame as I'm sure you know only takes a few minutes for the entire clock. You don't necessarily need a depthing tool for every-day work.

 

[roughbarked]

Of course, it is uneconomic to bush when this is not a problem to the clock.
However, if you happen to live in a smaller community where the people are going to bother you about their clock every time you bump into them while collecting your mail, you are probably best to not have to see their clock again for as long as possible.

 

[howtorepairpendulumclocks]

No-one wants returns, least of all me! Just saying', Try it. Bush only when depthing dictates it with little or no pivot polishing. Could be a an interesting experiment if you have time and you might be pleasantly surprised.

 

[roughbarked]

I have only ever bushed what needs bushing.

 

[howtorepairpendulumclocks]

Great! Heartening. Thank you. I suppose my motivation for banging-on about this is I think this thread was started by a beginner. I so often see the message to beginners that if the pivot wiggles about in the hole, it needs bushing. Rarely if ever, mention of depthing beforehand. Thanks for the chat ) all good.

 

[shutterbug]

A note to all as a reminder: we are not allowed to post offers to sell, buy or trade publicly here. Those types of communications must be by private messages, not here. OK?
I'm removing the messages above that allude to that activity. I recognize that it was a free offer, but to the casual reader that is not all that clear from the responses. Anyway, even when no money is involved, communication should be private after the offer is made.

 

[murphyfields]

A note to all as a reminder: we are not allowed to post offers to sell, buy or trade publicly here.

Funny, I think the buy/sell/trade part is what brought this thread back to life, and I kind of like where it is going, which is discussing some thing I hadn't considered. So I really appreciate that you keep sales out of the discussion forum, I still have to thank the person who wanted the tools.

Anyway, as a noobie with limited tools, how do you check the depthing? I have not seen this topic before, so very interested.

On a related note, I have been wondering, if you receive a clock and you believe that bushings have been put in incorrectly, how do you check and verify this, and how would you correct it?

 

[howtorepairpendulumclocks]

Check the depthing like this... you don't need a depthing tool, at least for the first stage...

Following preliminary cleaning - wash the clock and peg-out the pivot holes - start at one end of the train, normally the bottom end (great wheel) and put the mobiles in the frame in pairs. I don't know what your clock looks like but with a spring driven clock this will usually be the barrel and lower intermediate wheel. Using your fingers, put some resitance on the driven mobile, in this case, the intermediate wheel. Rotate the driving wheel (the barrel here) in the normal direction when the clock is running and check for smoothness of transmission of power. Given that the clock hasn't been extensively altered, check the smoothness with the wheels pushed together, neutral and apart. Yes it takes a bit of practice but you will get there.... If it feels smoother when the wheels are pushed together and noticeably less smooth when the wheels are apart, this suggests you have a depthing issue and you may have to bush or rebush. if there is no significant difference or in-fact, it feels smoother when the wheels are further apart, you do not need to bush. Bushing a mobile like this will likely make depthing worse. Work your way up the train like this, checking all the mobiles in pairs. remember, what you are interested in here from the perspective of the operation of the clock is, "will changing the centre distance between mobiles improve depthing?". If the answer is no or probably not, you don't need to bush. In any gear pair, particularly old clocks, meshing is unlikely to be perfectly smooth. How do you know whether your gears are at their optimal centre distance? Well, ideally you have a depthing tool and you test the pairs over a wider range than is available in the clock frame alone. In addition to the "feel" method described above, it is always, where possible, looking at the action of the engaging wheel teeth and pinion leaves through low-power magnification. Typically, but not always, the mobiles move apart as the pivots and pivot holes wear. This leads to more engagement before the line of centres (imaginary line between two meshing mobiles). This IS problematic as action before the line of centres is "engaging friction", often called by clockmakers "butting". Re-depthing through bushing returns mobiles to a more optimal centre distance and to a degree, evens-up action before and after the LOC. If you suspect a pair of meshing mobiles of butting, making the clock stop but they appear ok and you have done the above test, AS A TEMPORARY MEASURE, put a bit of 6B pencil or oil on the pinion leaves, this will reduce engaging friction. If the clock runs after lubricating the pinion, you likely have a depthing problem or the pinion is so badly worn that the effective Pitch Circle Diameter is beginning to reduce. Hope this helps and good luck. Remember, testing the mesh must be done under load. Spinning the wheels for this bit of diagnosis tells you very little.

 

[howtorepairpendulumclocks]

sorry, I didn't quite answer the last part of the question... how do you correct it? In a clock that has had significant intervention/damage etc and for whatever reason, it is decided to re-depth outside the range of bushing. Decide first which or both mobiles are going to move. Sometimes where the wheel and the pinion are at opposite ends of the arbor, just one end can be moved without upsetting uprighting too much. There are factors of course such as alignment of arbors with holes in dials and such which may mean you cannot move that particular mobile. Otherwise, you 'simply' start again by plugging the hole with cast brass and scribing a new centre with the depthing tool and drilling a new hole, broaching to final size. This is quite an unusual process that you only have to do now and again. Hope this helps

 

[murphyfields]

howtorepairpendulumclocks I haven't seen anything on this before. Very interesting (and I am guessing somewhat controversial). And if this is controversial, please add in opposing views.

First, is it fair to translate mobiles as gears? To me, mobiles are phones. But I want to get the terminology correct.

I assume the 6B pencil is a simple TEMPORARY graphite lubricant?

I have been wondering how depthing really works, since I assume that there is a goldilocks problem...too close and you will get major problems and probably nothing turns, too far and either the gears don't mesh at all or there is too much friction. But there has to be a range that is "just right" or the dang things would stop working after the slightest wear. And even if you think they are just right, a little flexing will cause them stop working. Your explanation is the first that I have seen that addresses how to tell where things should be.

If you actually have a depthing tool, do you try things the same way? Start too close and then gradually increase until things "feel good"? And then keep increasing until things go bad again? With experience, can you actually feel a good depth and a bad depth?

Finally, I am an engineer, although electrical and not mechanical (with all the bad and good that implies). Is there a way to quantify how good or bad a particular depth might be?

 

[howtorepairpendulumclocks]

Yes, I guess controversial. Conservative practice does get some people hot under the collar so I apologise for that.. I hope these fora are for an exchange of views though and yes please, I'm sure others will chip in with the way they do it. Yes, mobiles are gears but more specifically (I think) the name for the arbor, pinion, pivots and wheel as a unit. It may be a watch term so don't take my word for it! Yes, the pencil trick in this case is a temporary measure but it can be very useful (or artist's graphite stick), for bearing surfaces such as star wheel and jumper interface where oil will just get gloopy and cause problems (maybe). Yes re the Goldilocks zone. If in doubt, err on the side of the mobiles being slightly too close together as (normally) they push one another apart so centre distance increases, the effective wheel and pinion pitch circle diameters reduce with wear, and, action after the line of centres (disengaging friction) is what you tend to get more of when the depthing is a bit too "deep" (close together). This isn't without its own set of problems but given the choice...

With the depthing tool I start with the wheels totally disengaged and slowly move them together, as you say, through the smooth zone and out the other side. I then do this in the opposite direction, each time putting a pencil mark on the adjusting knob of the tool. Of course the depthing tool also allows you to observe the action more closely that in the clock frame (normally)... but be careful not to poke your eye with it!

Good question re quantitative evaluation of depthing. I'm out of my depth here (PTP),,, but,,, if you have a microset timer or other timing device, you could look at the sinusoidal variation in rate caused by cycles in transmission of power (torque) manifested through escapement error if your clock has an anchor recoil escapement. This might seem a bit far-fetched but if you are looking for "better" or "worse" (whatever that means), escapement error is useful (clock runs faster with more power and vice-versa). if your pair of mobiles is far enough down the train, "better" depthing will I think result in greater pendulum amplitude. Kind of linked to the earlier part of this sentence.

I presume in industry, there are ways of doing this. I know in Autodesk Fusion 360 and no doubt many other applications, this kind of thing can be modelled. I don't know them but believe there is a Horological Science chapter of the NAWCC who almost certainly will be better qualified to answer this. No doubt, members of this forum will be able to point you in the right direction.

Try the book "Gears for small mechanism" by Wilfred Davis.

It is I admit difficult to see depthing issues with relatively small clock gears. To that end, I've just had a local laser cutting service cut me a segment of a wheel and pinion out of plywood so I can see and demonstrate it better. If it is any good, I'll post a picture of it here if anyone is interested.

Good luck!