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BUSHING WITH A SHERLINE MILL

John P

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Has anyone here worked out the details for bushing clock plates with a mill?
What kind of plate holding fixture is needed? Can one be purchased?

johnp
 

Bruce Alexander

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What kind of plate holding fixture is needed? Can one be purchased?
Some folks make their own posts, but a setup can be ordered from Sherline:

https://www.sherline.com/product/2118-horological-milling-machine-bushing-and-depthing-accessory/

I use it and it works well. The only case in which I wasn't able to use it was when I wanted to use the set up as a Depthing Tool on a Herschede 9-tube movement. It wasn't "high" enough.

Here are a couple of links:

bushing with a mill

Bushing with a milling machine setup


Here is some information on Jerry's online course: Products by Category

Regards,

Bruce
 

Jerry Kieffer

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For those who are using a Sherline Mill for bushing, the attached photo shows My first movement holder and the Sherline holder. My holder on the left is larger and very rigid but is sometimes limited when holding plates where one would like to hold in a tight area. The Sherline holders are a little smaller and more versatile, but the half moon protective clamping block shown in the middle factory stock holder, can be time consuming in use at times. I modified mine by installing a spring loaded middle screw at the arrow shown in the holder on the right. This saves considerable time in use.

Jerry Kieffer

View attachment 578545

fullsizeoutput_544.jpeg
 

Uhralt

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For those who are using a Sherline Mill for bushing, the attached photo shows My first movement holder and the Sherline holder. My holder on the left is larger and very rigid but is sometimes limited when holding plates where one would like to hold in a tight area. The Sherline holders are a little smaller and more versatile, but the half moon protective clamping block shown in the middle factory stock holder, can be time consuming in use at times. I modified mine by installing a spring loaded middle screw at the arrow shown in the holder on the right. This saves considerable time in use.

Jerry Kieffer

View attachment 578545

View attachment 578546
I assume that the spring loaded screw is screwed into the half moon to pull it up. Correct? Seems like a good idea!

Uhralt
 

Jerry Kieffer

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I assume that the spring loaded screw is screwed into the half moon to pull it up. Correct? Seems like a good idea!

Uhralt
Uhralt
That would be correct and should have been included as part of the description.

Thanks for the clarification

Jerry Kieffer
 

John P

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Here is my set up so far. Im using the WW collet holder and trying to figure out a good way to center up on a bushing hole using a .31 gauge pin, a tapered pin, just anything to get some accuracy into the mix.
Could someone tell me what they use for centering up the plate before cutting the bushing?
P3280132.JPG P3270130.JPG
 

shutterbug

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If you can get your gauge pin sitting in the original hole, it should be right. They make pointed center finders that you could use too, but the gauge pin idea is a good one. Just match the size to the original hole.
 

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As SB mentions, I acquired a set of pin gauges and chuck up one that closely matches the diameter of the pivot.
I then set up center by carefully aligning with the unworn side of the pivot hole.
 

Uhralt

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As SB mentions, I acquired a set of pin gauges and chuck up one that closely matches the diameter of the pivot.
I then set up center by carefully aligning with the unworn side of the pivot hole.
If you choose a diameter very slightly larger than the original pivot, the gauge pin will only fit into the original center. I use a stereo microscope to watch closely how it enters the hole. If you see any deflection of the pin, you are not quite on center. I use this method only for small pivot holes of less than 1 mm. For the larger ones I use a tapered center finder. I still use the microscope to ensure that the center finder has found the largest diameter of the hole.

Uhralt
 
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Bruce Alexander

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If you choose a diameter very slightly larger than the original pivot, the gauge pin will only fit into the original center. I use a stereo microscope to watch closely how it enters the hole. If you see any deflection of the pin, you are not quite on center. I use this method only for small pivot holes of less than 1 mm. For the larger ones I use a tapered center finder. I still use the microscope to ensure that the center finder has found the largest diameter of the hole.

Uhralt
To each his own. I use magnification and plenty of light but I don't have a microscope on hand. I do look closely for deflection. It's not hard to see.
 

Uhralt

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To each his own. I use magnification and plenty of light but I don't have a microscope on hand. I do look closely for deflection. It's not hard to see.
I guess your eyesight is better than mine. For me, the microscope is very helpful.

Uhralt
 

Bruce Alexander

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I guess your eyesight is better than mine. For me, the microscope is very helpful.

Uhralt
Perhaps.

I usually have an "Optivisor" type headband on, and various hand held magnifiers nearby as well.
I wear glasses and have difficulty reading without them but my vision is adequate for now.

Bruce
 
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John P

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I have tried the pin gauges in my collet but when I rotate the spindle, there is wobble in the pin. How much pin should be sticking out of the collet.
Also I have tried pointed center finders and they all wobble when rotated by hand. All my equipment is new.
Here is what I am working with.
P3290140.JPG
The short one has no wobble at all but you have to run the spindle down so far you cant see to align the plate to the good side of the worn bushing.
P3280132.JPG

I have everything worked out but the issue of lining up the d shaped cutter to the bushing hole.

johnp
 

shutterbug

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There should not be any wobble if everything is inserted correctly and tight. Where do you see the wobble - just at the end or all along the shaft? Does the collet look bent at all?
 

Bruce Alexander

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I always check for run out under power before I try to line up on center. Keep your pin as short as possible while still being able to view the pivot hole. You can try to true it up with gentle finger pressure. You might try flipping the Pin Gauge to see if it runs truer on the other end. No doubt you've checked carefully for swarf, etc.

Actually, I have had pretty good results working with my 3-Jaw Chuck and Pin Gauges. They seem to run pretty true without making them too short to be useful. If you have one, try it. As an added bonus, it's a little faster for setup and tooling.

If I need to work with pivot holes 1mm or less, I'll work with my Collets but, again, for some reason I tend to observe more run out with them vs. the 3-Jaw Chuck in my Mill so that's my go-to. Some folks will close the jaws completely to use them as a press. I like to chuck up a plugging tool. Just my personal preference. I use the KWM System.

Pretty neat setup by the way.

Regards,

Bruce
 
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Jerry Kieffer

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Here is my set up so far. Im using the WW collet holder and trying to figure out a good way to center up on a bushing hole using a .31 gauge pin, a tapered pin, just anything to get some accuracy into the mix.
Could someone tell me what they use for centering up the plate before cutting the bushing?
View attachment 579110 View attachment 579111

John
On my initial setup for the use of gage pins for this application, the setup and my experience was/is as follows.

(1) I first made sure that no-one had placed a heavy load on a tommy bar inserted in only one hole of a empty spindle. Sherline cautions that the tommy bar be placed in both holes. If not a slight bur can be placed on the inside of the taper causing accuracy issues with the collet adaptor and other accessories. From this point the collet adaptor was setup per Sherlines instructions.

(2) My everyday beater collet set is a mix of known brand collets with the bad ones removed and replaced. Non of the collets are made in China nor would I suggest such collets from past and current experience.

(3) The range of Gage pins used for this purpose were rolled on a known flat surface such as a surface plate and checked for warpage since they are a import set.

(4) In use the gage pins are inserted in the proper size collet with about .375" to .500" extended from the front of the collet. Under the conditions above, no runout issues have been experienced using gage pins at about .020" diameter and above.

(5) When using gage pins about .020" and below, they can become quite unstable when providing the working clearance required. Under these conditions, I cut off a short piece of the pin and insert it in the nose of a watchmakers staking set stake per attached photo. Again, under this condition runout has not been an issue providing the pin was not warped and the stake is not defective.

Jerry Kieffer

fullsizeoutput_548.jpeg
 

John P

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If I shorten things up as suggested, runout is minimal but still there. I have a good selection of collets and many of the same size so I have changed them out and checked them in my lathe first. All are true in the lathe.
I leave the plate loose and lower my centering point down into the worn bushing, rotating it by hand until it starts to push the plate around.
Then lock the plate down. next I install the d shaped cutter with collet into the collet adapter and run the motor at its lowest speed while lowering the cutter down until the hole is cut out.
What is swarf?
Here is what is happening when I cut out a bushing
P3290067.JPG
The hole is off center and normally When bushing by hand I would walk my reamer over nibbing the hole back to center.
The ideal now and the reason I am doing this is to get it on center the first time.
P3290069.JPG
Here the cut looks better. I believe this would run fine with a new bushing installed. This one was done using the cutter to center the hole .

I have been bushing clock plates by hand for 16 years and I am good at it. I want to convert to machine bushing to perfect my skills and do a better more cleaner and accurate job.
The next movement that I need to rebuild will still be done by hand until I get this system worked out.

Any suggestions would be appreciated and thanks to all for your tips.

johnp
 
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gmorse

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Hi John,

What is swarf?
It's the metal fragments produced when you drill, mill or file anything. If even a small fragment gets between the spindle taper and the collet taper, or inside the chuck jaws, it will throw the pin or whatever you're holding off centre.

Regards,

Graham
 

shutterbug

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Jerry is the go to guy for all things related to lathes and mills, so study his post and be sure everything is set right on your mill. A small piece of swarf might have gotten into your equipment that you did not detect when you set it up.
 

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In some situations it may be feasible to hold the actual arbor in the mill and line up the plate with the pivot that actually goes there. The arbor is generally larger and stiffer than the pivot sized gauge pin. A lot depends on the design of the arbor (location of pinion and wheel in relation to pivots). I haven't tried it but visualize that it could work.
 

Jerry Kieffer

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If I shorten things up as suggested, runout is minimal but still there. I have a good selection of collets and many of the same size so I have changed them out and checked them in my lathe first. All are true in the lathe.
I leave the plate loose and lower my centering point down into the worn bushing, rotating it by hand until it starts to push the plate around.
Then lock the plate down.
Any suggestions would be appreciated and thanks to all for your tips.

johnp
John
Under the conditions mentioned above, the is no way to bush accurately.

How are you checking your collets for accuracy? As mentioned in post, #17, there should be no visible runout with a gage pin installed at about .500". Another words, you should see no more visible runout than when the Mill is turned off. What brand are your collets? Have you checked your gage pins to see if they are warped? Clean everything as others have mentioned.

Once you have resolved your gage pin runout problem, centering the spindle should be done by moving the slides only. If you attempt to move the plate around in centering attempts much like in a bushing machine, the exact center will almost always be lost when tightening the plate. One reason for using a Milling machine is to avoid this issue. Reaming with the reamer at the slowest Mill speed is the most effective method of reaming in a milling machine.

Jerry Kieffer
 

John P

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I check the collets(which are a mismatch of different makers) and pins in my watch lathe. They run true. I removed the collet adapter, cleaned and polished it.
The black coating is gone. That helped and there is no wobble in the pin now.

I have been trying to get a centering tool that would work on all the bushing holes. A universal tool per say. Hoping to avoid changing out collets and pins
as you move along the plate to another bushing size. Apparently this wont work as everything tried has some wobble.
If pins are the way to go, then that's what it will be. My set only goes up to .60 so I have to figure out what to do for worn bushings above that diameter.
The best set up for me now is to
mark the wear in the bushing with a sharpie, then place
the reamer under magnification with the flat side toward the wear. So far this has produced a good centered cut.
I need sherline #2118 tool post holder, to get things up a little higher so ill order that today.

Thanks for the help
Johnp
 
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Bruce Alexander

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Hello John,

Glad you were able to get your run-out issue solved. :thumb:

In January of last year I ordered the following Pin Gage Sets from Shars:

.011-.060" Minus Steel Plug Gage Set SKU 303-4501M0 ($16.95)
.061-.250" Minus Steel Plug Gage Set SKU 303-4503M1 ($38.95)

With shipping, the order set me back $72.54. Their level of precision has been more than adequate for my purposes. I've found a number of additional uses for the larger set. It has been a good return on investment in my opinion.

I know one very helpful member (dad1891) who has fabricated his own set of centering tools with a wide variety of sizes. I personally don't care to use the standard centering tool that I have. I originally ordered it for use on my Drill Press. As Jerry has detailed for us above, it is best to use only use the slides to get it properly centered. In other words, as I understand it, you don't want to let it self-center under a loosely held plate because you can lose some precision when you go to tighten the fasteners on your plate. Since that process requires visualizing the tool into the original pivot hole, I prefer to use the Pin Gauges because they give better visual access. Whatever you use, get plenty of strong light under your spindle. I augment my light source with a strong LED Flashlight because it allows me to quickly shift around pin and eliminate shadows. Again, that's just my personal preference for what I think works best in my hands. If I had the skills to machine my own tools I might have developed a different approach.

I think that the Sherline #2118 tool post is a good set up, but as I mentioned before, some movements have a little too much distance between plates in order to use these posts for a depthning tool set up. The two examples I've come across so far involved a Herschede Tall Case movement, and a Seth Thomas Lyre Movement with the external Escape Wheel Cock pointing down. Other than that, I've had no problems with bushing set-ups for one plate.

I like your use of the 1-2-3 Steel Blocks. I've been thinking of getting a set for a while now and when I saw your set up it occurred to me that I might be able to use them as riser blocks under the Sherline Posts with appropriately sized, longer bolts. There might be too much slop going through the holes in the Steel Blocks, but I'm going to give it a try. If it doesn't work, I've got a block of 3x3x1 Aluminum stock that I'll try machine into a custom set of riser blocks. I think that another inch should be sufficient.

I think you'll really like using your Mill for bushing work once you get up and running. Be forewarned that it will take more time, but with practice you'll be able to shave some time off. I think that the accuracy and certainty are worth it. I have no doubt that I'm doing a much better, much more consistent job of bushing on center than I have ever done using hand tools or my drill press.

Good luck.

Bruce
 
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Jerry Kieffer

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I check the collets(which are a mismatch of different makers) and pins in my watch lathe. They run true. I removed the collet adapter, cleaned and polished it.
The black coating is gone. That helped and there is no wobble in the pin now.

I have been trying to get a centering tool that would work on all the bushing holes. A universal tool per say. Hoping to avoid changing out collets and pins
as you move along the plate to another bushing size. Apparently this wont work as everything tried has some wobble.
If pins are the way to go, then that's what it will be. My set only goes up to .60 so I have to figure out what to do for worn bushings above that diameter.
The best set up for me now is to
mark the wear in the bushing with a sharpie, then place
the reamer under magnification with the flat side toward the wear. So far this has produced a good centered cut.
I need sherline #2118 tool post holder, to get things up a little higher so ill order that today.

Thanks for the help
Johnp
John
I am also happy to hear that you resolved your runout issue.

Personally, I use gage pins as part of a system when bushing not just for location. My goal is to return a movement back to original with original size pivot holes that are round and straight and aligned parallel with the arbors. This is done by selecting a pin sized for position location and then ground and utilized as a bushing pivot hole reamer per attached photo. Bushing would be at the arrow side.

Back when I started I first used the hand bushing method commonly suggested. After making a "Birds nest hole" with a broach to achieve a 5 degree tilt and then enlarging it with a smoothing broach, it hit me one day that I was not meeting my work quality goals. While selecting two or three pins for a typical movement takes a few seconds, reaming a pivot hole with a preselected reamer is much faster than the broach/smoothing broach routine. The really nice thing about the Mill is that if by accident I end up producing a ticker or non runner, It offers a effective and efficient method of correcting the issues including those of others.

Jerry Kieffer

fullsizeoutput_54b.jpeg
 
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dad1891

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John,

Bruce mentioned my centering points in one of the earlier posts, so I guess it's appropriate to show you what they look like and how I use them. After purchasing my mill, I spent the better part of a day with a Last Word gauge, looking at the tolerances of the machine and making sure that it was set up correctly. I found near zero runout on the spindle taper and the collet adapter, but each of the collets had some runout. The 1/8" collet was most concerning because it had 0.0012 TIR runout and I knew I would be using it a lot. Another consideration was that collets are most accurate when holding a piece that is the exact size of the collet (0.125" pin in an 1/8" collet). All of the commercial centering points that I found had a larger angle on the point than I liked. The large angle on the point allows using one point for a wide variety of hole sizes, but the compromise is that it is much more sensitive to the condition of outside face of the hole. I finally decided that it would be necessary to make my own centering points to achieve highest accuracy.

I settled on a 5 deg angle for the points, which meant that I would have to make 5 of them to cover all bushing sizes.
IMG_8653.JPG

To compensate for the runout in the collet, I took the head off my mill and mounted it on my lathe. I then match-marked the spindle to the collet holder and the centering pins to the collet with pink fingernail polish. I turned the shank on each centering point to 0.125" dia. Then I set the head at a 2.5 deg angle and turned the tapers on the centering points while holding them in the 1/8" collet with all of the match marks aligned. Two of the points have 0.0002 TIR at the tip and the other three have 0.0000 runout.

I purchased the Sherline horological plate holders, but I found that their height gets in the way when bushing holes that are near the holder. Finally decided to make my own, which are shown below.
IMG_8382.JPG
Mark the pivot holes with the position of the original pivot. Place the plate on the holders, making sure that there is some room for the plate to move in all directions without binding on the hold-down clamp screws. Then plunge the centering point into the pivot hole, while holding gentle horizontal pressure between the original hole location and the centering point. Tighten the hold down screws and bore the bushing. The Sherline mill has a very sensitive "feel" and you can very easily tell when the centering point is solidly against the plate. Don't force the point down after it makes solid contact, as this just flexes the plate and potentially introduces errors.

The method that I settled on for bushings is that I purchased center cutting end mills that were slightly smaller than the commercial reamers (for the smaller sizes, they are less than $10 each). Once the plate is locked in place, I chuck the mill (which usually has an 1/8" shank) and bore out the old oblong hole. I then remove the collet and drawbar and drop a custom reamer holder that I made through the spindle. Then I hand ream out the last few thousandths and drop in a piece of 1/4" round stock that I use to tap the bushing into place. If you need to trim the bushing, you are already centered up, just throw the collet back in and trim away.

Without getting into details of how I made the measurements, I checked the procedure with 4 different bushings and found that the bushings were centered on the original hole within a minimum of 0.0008" and a maximum of 0.0012".

I would strongly recommend using Jerry Kieffer's method of using gauge pins to bore the bushings to size. I usually don't pay any attention to the old pivot hole size, I just mike the pivot, select a gauge pin that is 0.0015 to 0.002" larger and bore to that size. I think you will find it to be very close to the "ideal" 5 deg lean.

I hope this helps.

Dave Diel
 
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TEACLOCKS

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John,

Bruce mentioned my centering points in one of the earlier posts, so I guess it's appropriate to show you what they look like and how I use them. After purchasing my mill, I spent the better part of a day with a Last Word gauge, looking at the tolerances of the machine and making sure that it was set up correctly. I found near zero runout on the spindle taper and the collet adapter, but each of the collets had some runout. The 1/8" collet was most concerning because it had 0.0012 TIR runout and I knew I would be using it a lot. Another consideration was that collets are most accurate when holding a piece that is the exact size of the collet (0.125" pin in an 1/8" collet). All of the commercial centering points that I found had a larger angle on the point than I liked. The large angle on the point allows using one point for a wide variety of hole sizes, but the compromise is that it is much more sensitive to the condition of outside face of the hole. I finally decided that it would be necessary to make my own centering points to achieve highest accuracy.

I settled on a 5 deg angle for the points, which meant that I would have to make 5 of them to cover all bushing sizes.
View attachment 580326

To compensate for the runout in the collet, I took the head off my mill and mounted it on my lathe. I then match-marked the spindle to the collet holder and the centering pins to the collet with pink fingernail polish. I turned the shank on each centering point to 0.125" dia. Then I set the head at a 2.5 deg angle and turned the tapers on the centering points while holding them in the 1/8" collet with all of the match marks aligned. Two of the points have 0.0002 TIR at the tip and the other three have 0.0000 runout.

I purchased the Sherline horological plate holders, but I found that their height gets in the way when bushing holes that are near the holder. Finally decided to make my own, which are shown below.
View attachment 580327
Mark the pivot holes with the position of the original pivot. Place the plate on the holders, making sure that there is some room for the plate to move in all directions without binding on the hold-down clamp screws. Then plunge the centering point into the pivot hole, while holding gentle horizontal pressure between the original hole location and the centering point. Tighten the hold down screws and bore the bushing. The Sherline mill has a very sensitive "feel" and you can very easily tell when the centering point is solidly against the plate. Don't force the point down after it makes solid contact, as this just flexes the plate and potentially introduces errors.

The method that I settled on for bushings is that I purchased center cutting end mills that were slightly smaller than the commercial reamers (for the smaller sizes, they are less than $10 each). Once the plate is locked in place, I chuck the mill (which usually has an 1/8" shank) and bore out the old oblong hole. I then remove the collet and drawbar and drop a custom reamer holder that I made through the spindle. Then I hand ream out the last few thousandths and drop in a piece of 1/4" round stock that I use to tap the bushing into place. If you need to trim the bushing, you are already centered up, just throw the collet back in and trim away.

Without getting into details of how I made the measurements, I checked the procedure with 4 different bushings and found that the bushings were centered on the original hole within a minimum of 0.0008" and a maximum of 0.0012".

I would strongly recommend using Jerry Kieffer's method of using gauge pins to bore the bushings to size. I usually don't pay any attention to the old pivot hole size, I just mike the pivot, select a gauge pin that is 0.0015 to 0.002" larger and bore to that size. I think you will find it to be very close to the "ideal" 5 deg lean.

I hope this helps.

Dave Diel


What metal did you use to make the tapered centers :???::???:? Centering points
 

Bruce Alexander

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Thanks for sharing your methods Dave. I was hoping that you would weigh in. I've always thought you had a good approach. At this point, I've settled into "sighting" center in with Pin Gauges whether I have them held in a Collet or a Self-Centering 3-Jaw Chuck...which works remarkably well I think. I did finally pick up a Last Word kit. Used it for the first time just this week re-centering a bent C-2 pivot on a Sonora 8-Bell movement. When I thought I had it centered by sight, I was surprised to see just how far off it still was.

I plan to go back and check both my Lathe and Mill and bushing set ups for run out as you've described. So far, as is, I think I've achieved some excellent results "right out of the box". You certainly have taken things to the next level.

On infrequent occasions, I have needed to be creative with plate positioning while using the Sherline Holders but they have not yet blocked my access to a pivot hole. Of course, if I have to fiddle around with the plate, that can eat into the clock.

Can you use your holders for a depthning setup? I wish Sherline made theirs a little taller for such use.

If you don't mind my asking, using your Tapered Centers, what would you say your average time per bushing is?

Thanks,

Bruce
 

John P

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My centering pins are made from steel except the brass one. I used hardened points that have been laying around or used in other clock related tooling.
I put them in my lathe and straighten them much like straightening a bent pivot .

The blocks on my set up will work fine except they need to be higher to accept Hermle plates such as the 1161, 3 chime.
I now believe the use of pin gauges to align the cutter to the hole is the absolute way to go.
All the bushings get a circle scribe using my magic center finder. This circle gives me something to check after the bushing is cut. It is easy to see if your cut is off center. I am now doing work that is perfectly centered and clean cut ready for a bushing without hand broaching. It takes more time to do a set of plates but it is
a wonder to behold.
Doing bushing work by hand is absolutely a must learn for clock work. There will be times when you need to fall back on that skill.
P4020082.JPG

P4020079.JPG The clamps came from my French clock test stand made years ago.
Improvements to block hold down screws
 
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dad1891

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What metal did you use to make the tapered centers :???::???:? Centering points
Rotgut steel bar stock from Home Depot. That was a mistake because I could feel variations in hardness as I was turning the points. There is no potential for wear because there is almost no force on them and I never have the mill running when they are in contact with the plate.
 

dad1891

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Thanks for sharing your methods Dave. I was hoping that you would weigh in. I've always thought you had a good approach. At this point, I've settled into "sighting" center in with Pin Gauges whether I have them held in a Collet or a Self-Centering 3-Jaw Chuck...which works remarkably well I think. I did finally pick up a Last Word kit. Used it for the first time just this week re-centering a bent C-2 pivot on a Sonora 8-Bell movement. When I thought I had it centered by sight, I was surprised to see just how far off it still was.

I plan to go back and check both my Lathe and Mill and bushing set ups for run out as you've described. So far, as is, I think I've achieved some excellent results "right out of the box". You certainly have taken things to the next level.

On infrequent occasions, I have needed to be creative with plate positioning while using the Sherline Holders but they have not yet blocked my access to a pivot hole. Of course, if I have to fiddle around with the plate, that can eat into the clock.

Can you use your holders for a depthning setup? I wish Sherline made theirs a little taller for such use.

If you don't mind my asking, using your Tapered Centers, what would you say your average time per bushing is?

Thanks,

Bruce
I have no doubt that pin gauges would work as well or better than my method, but I was concerned about three things:
1. It takes a little time to find the right pin gauge for each hole.
2. The pin gauge takes a different collet than the cutter, which is another change.
3. I have found that optical centering can be deceptive. I'm not saying that it can't be done, I'm saying that it doesn't seem to work for me. Could be that I was born cockeyed.

I think you will be pleased with that Last Word. The initial purchase stings a little, but the small size is very handy with the little Sherline mill.

It takes me about 15 minutes to install a bushing. Kind of slow, but my pride in workmanship is more important to me than my time.

I haven't had an occasion that I needed to use the holders for depthing. They hold the plate at exactly the same height as the Sherline holders. It took quite a bit of time to make them.

One more thing is that I would like to thank Jerry Kieffer for guidance on where to buy and how to use pin gauges. I couldn't live without them.

Be Well

Dave Diel
 

Bruce Alexander

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Doing bushing work by hand is absolutely a must learn for clock work.
I agree. For most folks I think this is true. Of course there are the truly gifted who are always several steps beyond us before they first pick up a wrench.

It takes me about 15 minutes to install a bushing. Kind of slow, but my pride in workmanship is more important to me than my time.
That sounds very reasonable to me. I think that speed is where a Bushing Machine will excel but I'm not a professional shop doing volume work. I'd rather have the versatility of a Mill.

One more thing is that I would like to thank Jerry Kieffer for guidance on where to buy and how to use pin gauges. I couldn't live without them.
Well, you passed that along to me so I thank both of you for your help and guidance!

Regards,

Bruce
 

John P

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I received the new block set and drill chuck from Sherline yesterday. Blocks are still not high enough. The drill chuck was covered with a grease like protective coating and wrapped in wax paper.
While cleaning it up I began to wonder if the mill spindle was ever cleaned. Well no it wasn't. I poked a paper towel wet with carb spray up from the bottom and all kinds of funk was in there. You would think sherline would recommend a spindle cleaning before inserting any tooling. Must have a lot to do with accuracy.
Anyway a word to the wise, check and clean the spindle taper and tube.

johnp
 

Bruce Alexander

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Hi John,

Blocks are still not high enough
I've got a set of 1-2-3 Blocks on the way along with a couple of 3 1/2" Fasteners (Ridiculously expensive from Fastenal) which should work with the T-Nuts. I'll report on how I think they'll work out as riser blocks for the Sherline Posts. It would be nice if Sherline Made these Posts taller, especially since they specify they can be used as part of a Depthniing Set Up (It currently can for an "average" mantel clock movement). They would need to charge more for materials I suppose but I think it would be well worth it.

You would think sherline would recommend a spindle cleaning before inserting any tooling.
They do warn that their equipment and parts should be cleaned with Mineral Spirits (or similar) to remove their corrosion preventative, but I don't recall whether they specify or stress any one area. I think Machinists just routinely check/clean these areas/surfaces for swarf before every setup.

We learn by doing, eh?

Regards,

Bruce
 

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Hello John,

My 1-2-3 Steel Blocks arrived today and I think they'll work very well as riser blocks under Sherline's SKU 2118, Horological Milling Machine Bushing and Depthing Accessory.

I found that there wasn't an excessive amount of clearance between the T-Nuts and the Threaded Holes of my 1-2-3 Blocks. Even within the smooth bore holes there wasn't an excessive amount of slop. When tightened normally, the set up provides plenty of stability to locate and ream/drill on center. The set up reverts to normal for actual placement of the bushing, or it can be pressed home without further use of the Mill.

I had planned to machine my own riser blocks from Aluminum Stock and purchased 10-32 3.75" socket-head machine bolts. These bolts were a little too long for use on the 1" side of the blocks. The original bolts measure 2.415" in length. Adding approximately 1", I think 3.25" fasteners should work out just fine. I cut mine down to approximately 3.4".

In any case, I think that the additional inch of clearance should give plenty of room both below as well as above the assembled movement plates when needed for depthing purposes.

Thanks for the great idea! I think this will work out fine. :thumb:

Regards,

Bruce

Plate requiring more clearance due to riveted cock/post
Insufficient Clearance.jpg

Parts needed
Parts Needed.jpg

Post line up
LineUp.jpg

Set up
Clearances.jpg
 
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John P

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Bruce, I have oriented my 1-2-3 blocks for a 2 inch lift. It will clear for the hermle and urgos chime posts. Now just to locate some 10/32 threaded rod. P4040085.JPG
 

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Bruce, I have oriented my 1-2-3 blocks for a 2 inch lift. It will clear for the hermle and urgos chime posts. Now just to locate some 10/32 threaded rod. View attachment 580857
Hi John,

You just need to add 2" to the length of the original fasteners.

On the pricey side but I think these might work. #10-32 x 4-1/2" ASTM A574 Hex Drive Black Oxide Finish Alloy Steel Socket Cap Screw | Fastenal
If you have a local store, they can ship there for pick up to avoid shipping charges.

There's an online source called the Bolt Depot. Socket cap, Alloy steel black oxide finish, #10-32 x 4-1/2" - Bolt Depot They are a lot less expensive but I don't know what their shipping and handling charges will be. If you need other fasteners, that might be the way to go.

Please let us know if you find a more competitive source.

Be sure to confirm the length measurement. I think the length needs to end somewhere between 1/4" and 1/2". If 4 1/2" is a little too long, you can also add another washer or two up top, or trim it back a little. It might work fine as is. Three quarters is just a little too long as I found out with my 3 3/4" fasteners.

You might start to run out of working space above the plate depending on what you chuck up in your spindle. The additional 2" might be a practical limit.

Regards,

Bruce
 

John P

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The mill I purchased is the 5400 Deluxe and it came with the extended vertical mill column. 1 1/2 inch taller than standard 14 inch.
I have room to work even with the chuck installed.


Another very useful tool I made is a 6 inch x 3/8 wooden dowel with a powerful earth magnet epoxied into one end. This allows me to drop a long tool from the top down into a collet and remove it the same way. Like a tool from a staking set. Very helpful for certain applications
Saves time and lots of cranking up and down.
 

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Hello John,

Yes, I have the 5410 with an extended column as well.(Edit: I have the basic 12" Column NOT the 15" Extended Column) I like metric because the bushings are calibrated that way, but metric pin gauges cost a lot more for some reason, so I went Imperial with them and use a quick conversion chart that Dave was kind enough to share.

I may just give your magnetic tool a try. Sounds pretty neat. Thanks for sharing.

I really wanted the riser blocks for use when depthing is needed.

One can ream from either side of the plate. Since the walls of the prep are parallel, it doesn't matter. You just need to make sure that the bushing is flush with the inside surface of the plate once it's fully seated.

I like using the support cylinder to insure that the plate doesn't flex, but I suppose that's only likely to become a potential issue when pressing bushings into place. Reaming (or drilling) shouldn't take that much downward force.

I may go ahead and get the 4 1/2" Fasteners the next time I place an order for fasteners, washers or such. I think that the extra inch should be sufficient for most Mantel and Wall Clock Movements.

I actually first got the idea while browsing the Sherline Catalog. They offer a Cutoff Tool Rear Mounting Block (Cutoff Tool Rear Mounting Block – Sherline Products)
They could offer something similar for their Bushing/Depthing Posts Kit, but I kind of like the flexibility of the 1-2-3 blocks. There remains the question of the support cylinder, but that's not useful when both plates are in the setup anyway.

Regards,

Bruce
 
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John P

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Bruce those blocks look like the perfect solution for raising the working surface. Ill stick with the 1-2-3 for now .
I am still working with cutting the hole on center and not very good at it. I need better light but we are on lock down here.
I have more time to fiddle with it now that clock work has slowed.
 

MuensterMann

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I like metric because the bushings are calibrated that way, but metric pin gauges cost a lot more for some reason, so I went Imperial with them and use a quick conversion chart that Dave was kind enough to share.
I guess it doesn't matter if pins are metric or imperial, since you want one the same size of pivot or even slightly larger - so the pins to select from just need to have a good assortment of close sizes. Why is conversion needed? Is it because you measure in metric only?
 

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I guess it doesn't matter if pins are metric or imperial, since you want one the same size of pivot or even slightly larger - so the pins to select from just need to have a good assortment of close sizes. Why is conversion needed? Is it because you measure in metric only?
You bring up a good point MuensterMann. I need to do conversions when I'm using my Metric Collets. I also like to use a manual outside Micrometer when measuring pivots and it's calibrated in Metric. It's accurate, doesn't need batteries and is good for spotting pivot taper.

If I'm working with a 3-Jaw Chuck instead of my Collets, I could eliminate the need to convert by using my Digital. I think I'm going to replace my Digital Calipers soon and need to give it some serious thought before I do now that I'm bouncing between the two Systems. :confused:

Thanks,

Bruce
 

Uhralt

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You bring up a good point MuensterMann. I need to do conversions when I'm using my Metric Collets. I also like to use a manual outside Micrometer when measuring pivots and it's calibrated in Metric. It's accurate, doesn't need batteries and is good for spotting pivot taper.

If I'm working with a 3-Jaw Chuck instead of my Collets, I could eliminate the need to convert by using my Digital. I think I'm going to replace my Digital Calipers soon and need to give it some serious thought before I do now that I'm bouncing between the two Systems. :confused:

Thanks,

Bruce
If you plan to replace your digital calipers with high quality digital ones it will easy to switch between metric and imperial by a push of a button. The only issue is that the caliper will provide imperial results in decimals of an inch and the collets are labeled in fractions of an inch. So, still the need to convert.

Uhralt
 

MuensterMann

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Seems the 5400 is a better one for bushing than the 5000 - at least more common. Is the extended arm option a must for clock work? I see the 2000 unit have more room. Since the 2000 moves in more directions - does that affect any bushing accuracy just due to tolerances?
 

Bruce Alexander

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In my limited experience the 12" 5400 (5410) Deluxe is adequate for clock work that I do...mostly mantels. If you work on large movements and/or plates with long riveted posts you may want to consider the 15" extended column upgrade.
 

MuensterMann

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Thanks Bruce for your input! Is it a gain of 3 or 4 inches? Not sure how the 2000 compares, but a column extender is not listed as an option.
 

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I'm not sure MuensterMann as I went with the standard 12" column. My guess would be an additional 3". The 12" Column has been adequate for my purposes but recently I've been working with a Hermle Tall Case Movement which has the multiple riveted Triple Chime Posts. Depending on your tooling, they can be a little difficult to work around. If you work with large movements I think it's worth considering. I have no experience with the 2000 series.

Bruce
 

John P

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P4110066.JPG P1010113.JPG
This set up works well with Hermle and Urgos movements with plenty of clearance for chime studs. I have the extended column 5400 and a new set of gauge pins
in the larger sizes .61 to .250.
I have a huge old urgos movement that needs the lower end and 2nd wheels rebushed and I am going with butter bearings. Now that I have the large gauge pins
the learning process continues.

johnp
 
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Bruce Alexander

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Is it a gain of 3 or 4 inches?
Hey M.Mann. I checked Sherline's website and they claim that the 5400 Series 15" Extended Column upgrade increases the range from 6" of travel to 10+". For the additional $94.50, I think it's worth it.

It really depends on what type of clocks you plan to work on but if it's within your budget, I think it's better to have the extra head space and not need it than the other way around.

I also placed some Butter Bearings in that Hermle 1171 movement I was talking about earlier and the necessary drill bits are pretty long. In one case, I simply had to fall back to my Bench Top Drill Press. After working with the Sherline Mill, prepping plates with my Drill Press seemed as though I was trying to work during an Earthquake! I "got 'er done" but I really didn't care much for it at all.

Hope that helps.

Bruce
 

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