Jump to content

Help Fitting New Hands


Tracy

Recommended Posts

I purchased some (90-150 Blue Dauphine) hands (P/N 86.9142) from Esslinger. I wanted to verify that I ordered the correct size. I am new to watch repair—but am an experienced machinist so I am ok with measuring using calipers.

I measured the hour wheel on my Raketa (Movement 2614.H) at: 1.549mm (.061”) and the cannon pinion dia. at .965mm (.038”). I ordered the new hands size .90mm and 1.50mm (90-150) assuming that because the shafts are slightly larger their diameter would provide an interference fit for the smaller diameter hand holes.

hour wheel shaft is 1.549 – 1.50 hand hole = .049mm interference fit.

 minute dia. is .965 – .90 = .065mm interference fit.

 Are my assumptions correct about the interference fit? Did I order the correct size? 

When I try to fit the hands to the hour wheel/cannon pinion I cannot get them started. I have no trouble getting the old hands to fit??  I even tried to fit the new hands upside down (because of the flange created when the mfg. stamped out the hands/hole) and still could not get them started. Any advice would be helpful.

Thanks, Tracy

 

 

Raketa WatchInside.jpg

Link to comment
Share on other sites

10 minutes ago, Tracy said:

I purchased some (90-150 Blue Dauphine) hands (P/N 86.9142) from Esslinger. I wanted to verify that I ordered the correct size. I am new to watch repair—but am an experienced machinist so I am ok with measuring using calipers.

I measured the hour wheel on my Raketa (Movement 2614.H) at: 1.549mm (.061”) and the cannon pinion dia. at .965mm (.038”). I ordered the new hands size .90mm and 1.50mm (90-150) assuming that because the shafts are slightly larger their diameter would provide an interference fit for the smaller diameter hand holes.

hour wheel shaft is 1.549 – 1.50 hand hole = .049mm interference fit.

 minute dia. is .965 – .90 = .065mm interference fit.

 Are my assumptions correct about the interference fit? Did I order the correct size? 

When I try to fit the hands to the hour wheel/cannon pinion I cannot get them started. I have no trouble getting the old hands to fit??  I even tried to fit the new hands upside down (because of the flange created when the mfg. stamped out the hands/hole) and still could not get them started. Any advice would be helpful.

Thanks, Tracy

 

 

Raketa WatchInside.jpg

Hello Tracey,

Welcome to the forum. I think your calculations are correct, but the measurements may be off. Here is what I found for the Raketa movement you've specified:

58d68d5d5b051_ScreenShot2017-03-25at11_28_01AM.thumb.png.aa0a23f837089dd5bea6131e2225cf3d.png

 As you can see, the hour hand is specified at 1.60mm and the minute hand 1.04mm.

I buy from Esslinger all the time, and you can send the hands back. Try to get some closer to what you need especially that minute hand. You don't want to force either hand onto its shaft, and in my experience, forcing that minute hand if it doesn't fit will result in bending both hands in the process.

J

Link to comment
Share on other sites

Strange as they should fit. You are correct they are fitted by a interference fit. I am not sure what the interference fit should be. You need to measure the old hands. The essayist way is to insert a brass/steel pin into the old hand & mark & measure where they sit.

PS What method are you using to fit the hands.

Link to comment
Share on other sites

10 minutes ago, Tracy said:

I purchased some (90-150 Blue Dauphine) hands (P/N 86.9142) from Esslinger. I wanted to verify that I ordered the correct size. I am new to watch repair—but am an experienced machinist so I am ok with measuring using calipers.

I measured the hour wheel on my Raketa (Movement 2614.H) at: 1.549mm (.061”) and the cannon pinion dia. at .965mm (.038”). I ordered the new hands size .90mm and 1.50mm (90-150) assuming that because the shafts are slightly larger their diameter would provide an interference fit for the smaller diameter hand holes.

hour wheel shaft is 1.549 – 1.50 hand hole = .049mm interference fit.

 minute dia. is .965 – .90 = .065mm interference fit.

 Are my assumptions correct about the interference fit? Did I order the correct size? 

When I try to fit the hands to the hour wheel/cannon pinion I cannot get them started. I have no trouble getting the old hands to fit??  I even tried to fit the new hands upside down (because of the flange created when the mfg. stamped out the hands/hole) and still could not get them started. Any advice would be helpful.

Thanks, Tracy

 

 

Raketa WatchInside.jpg

Hello Tracey,

Welcome to the forum. I think your calculations are correct, but the measurements may be off. Here is what I found for the Raketa movement you've specified:

58d68d5d5b051_ScreenShot2017-03-25at11_28_01AM.thumb.png.aa0a23f837089dd5bea6131e2225cf3d.png

 As you can see, the hour hand is specified at 1.60mm and the minute hand 1.04mm.

I buy from Esslinger all the time, and you can send the hands back. Try to get some closer to what you need especially that minute hand. You don't want to force either hand onto its shaft, and in my experience, forcing that minute hand if it doesn't fit will result in bending both hands in the process.

J

Link to comment
Share on other sites

Sometimes it helps to broach the opening of the hand collet with a pin, just to get it started when fitting. New hands can be quite tight to fit (eg. new Omega hands often take a lot of pressure to fit).

  • Like 1
Link to comment
Share on other sites

I don't get the logic. If the shafts measure 1.549mm and .965mm respectively, why would the spects for the movement call for 1.6mm  and 1.04mm? That's like saying I have an axle shaft that's 1, 1/2" in diameter and I'm going to press a bearing on to it that has an inter race diameter of 1, 5/8"---there is no press/interference fit and the bearing would just slide into the shaft????

I get that the movement spects call for 1.6mm and 1.04mm hands however they should be too large. Is there an alternate universe for watch hand measurements?

I do like the idea of using a pin to broach the hands to get them started.

Also, If I try to reuse the old hands (hour hand was a little loose) any way to tighten it up a bit??

Thanks for all the help/advice.

 

 

Link to comment
Share on other sites

Hi and welcome.
I constantly order new hands even the size quoted from a tech sheets only to find they are too tight ! I suspect the problem is they are aftermarket affairs and the quality is dubious.
If you try to force the hands on, not only can you damage the hands, you could push the jewel out or alter the "End Shake"
Using a pin to widen the inside diameter is sort of ok but it's better to ream them.
Esslinger should stock an appropriate set of Reamers but not the Cutting triangular type, you want the Pusher type.
You can also buy boxed selections of watch hands of varying sizes which will always be useful to have.

Sent from my SM-G920F using Tapatalk

Link to comment
Share on other sites

I don't get the logic. If the shafts measure 1.549mm and .965mm respectively, why would the spects for the movement call for 1.6mm  and 1.04mm? That's like saying I have an axle shaft that's 1, 1/2" in diameter and I'm going to press a bearing on to it that has an inter race diameter of 1, 5/8"---there is no press/interference fit and the bearing would just slide into the shaft????
I get that the movement spects call for 1.6mm and 1.04mm hands however they should be too large. Is there an alternate universe for watch hand measurements?
I do like the idea of using a pin to broach the hands to get them started.
Also, If I try to reuse the old hands (hour hand was a little loose) any way to tighten it up a bit??
Thanks for all the help/advice.
 
 

Sorry I missed the second part of your enquiry.
Yes it's possible to renovate your existing hour hand. You will need a staking set but make sure it's not the cannon pinion that is loose.
2 methods I've used with my staking set.
1. With the hand shaft upwards place a hollow stake with a rounded edge over the bore diameter but larger than the bore. Gentle tap on the stake will displace the metal and decrease the bore .
2 . Using a pointed stake closer to the bore, tap gently which will displace metal and cause a forward protrusion of metal inside the bore diameter, which should grab onto the cannon pinion

Sent from my SM-G920F using Tapatalk

Link to comment
Share on other sites

1 hour ago, digginstony said:

Hi and welcome.
I constantly order new hands even the size quoted from a tech sheets only to find they are too tight ! I suspect the problem is they are aftermarket affairs and the quality is dubious.
If you try to force the hands on, not only can you damage the hands, you could push the jewel out or alter the "End Shake"
Using a pin to widen the inside diameter is sort of ok but it's better to ream them.
Esslinger should stock an appropriate set of Reamers but not the Cutting triangular type, you want the Pusher type.
You can also buy boxed selections of watch hands of varying sizes which will always be useful to have.

Sent from my SM-G920F using Tapatalk
 

@Tracy I know you've mentioned your experience as a machinist, but it really is easier to buy hands that are the correct size. It will save you a LOT of potential trouble. As @digginstony has already stated, I also have found that ordering hands by technical specs STILL results in hands that are too tight and have to be worked a little with a broaching pin or staking set if you have one. Do you know what happens when you make incorrect hands fit? They work for a while, then when you start wearing the watch, will start to lose grip :pulling-hair-out:whenever they feel like it.

J

Link to comment
Share on other sites

Hi and welcome.
I constantly order new hands even the size quoted from a tech sheets only to find they are too tight ! I suspect the problem is they are aftermarket affairs and the quality is dubious.
If you try to force the hands on, not only can you damage the hands, you could push the jewel out or alter the "End Shake"
Using a pin to widen the inside diameter is sort of ok but it's better to ream them.
Esslinger should stock an appropriate set of Reamers but not the Cutting triangular type, you want the Pusher type.
You can also buy boxed selections of watch hands of varying sizes which will always be useful to have.

Sent from my SM-G920F using Tapatalk



Ooops I meant set of broaches not the triangle cutting type

Sent from my SM-T585 using Tapatalk

Link to comment
Share on other sites



  • Similar Content

  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • I've remained silent on this thread, and at the risk of upsetting everyone, the thing that worries me the most the the apparent absence of Mark. The moderators do a great job and the members also pitch in, and the site seems to run itself, but it is a concern for the future of this forum when the owner is absent for all intents and purposes. Like many of the comments above I would hate to log in one day and things be closed down as I rely on this site for ideas and knowledge and also cheer me up. maybe the Moderators could reach out to him, assuming he does not read this thread, and express our concerns and let us know the plans going forward? some kind of WRT ark
    • That was the exact reason for me starting this thread watchie. Still we haven't worked out how the regulars are going to hook up if it goes tits up. I honestly think something should be arranged to stay in contact, we all help each other so much. 
    • Yeah ive watched that a few times before,  i couldnt find my old school dividers to scribe it up 😅 Yep thats the guy i bought a roll from . Thanks Nicklesilver that answers that perfectly and more or less what i thought an experiment over time would prove . The jumper arm is quite thick along its length, i left it that way intentionally, i thought the original was probably very thin, i didnt see that it was already missing. Setting isn't particularly stiff as such just positive, i still need to take it out and polish where it mates with the stem release. 
    • Yes, "Sold out" is difficult to understand. There doesn't seem to be a lot going on. It's been nine months since any new video was published on the Watch Repair Channel. The Level 4 course on watchfix.com has been in progress for what feels like forever (several years!?). Maybe Mark's enterprises aren't doing well or perhaps already so profitable there's nothing much to motivate him for more material. Or, perhaps these days he's more into crochet. The real reason is probably something entirely different but it would be nice/interesting to know. I don't mean to sound gloomy or pessimistic, but I wouldn't be surprised to be met by an HTTP 404. Every day feels like a gift. Speaking of watchfix.com I've been postponing the "Level 5: Servicing Chronograph Watches" course for a very, very long time. Anyway, I just enrolled on it so it's going to be very interesting to see the videos. I must say, IMO there's nothing really that can compete with Mark's courses when it comes to presentation and video quality. It's simply world-class and makes me associate with some really expensive BBC productions.
    • Steel has some funny properties, or at least counterintuitive. The modulus of elasticity is effectively (not exactly, but close enough) the same for steel that is annealed and hardened. What changes is the point of plastic deformation* . If the movement of your spring doesn't pass that, it should work fine. It looks a little thick, I would thin it a bit maybe from the main body out about halfway, maybe 10-20% thinner (not in thickness, along its form). But if it works it works!   *So- if you have two bars of the same steel, one annealed, one at 600 Vickers (general hardness watch arbors might be), clamp them to a table so the same length is hanging out, and put a weight on the ends, they will bend the same amount. But if you continue to add weight, then remove it, at a point the annealed bar won't return to its original straightness. That's the point of plastic deformation. But up to that point, as springs, they are the same. However- their wear characteristics will be very very different. And getting the hardened bar past its point of plastic deformation takes a lot more effort.
×
×
  • Create New...