Compatibility of pallet forks with part number "710"

[stm]

While trying to service an Osco 66 movement (https://ranfft.org/caliber/8624-Osco-66D) I broke the axis of the pallet fork. The part number of the pallet fork for this movement is "710" according to the Emmy Watch database.

I'm looking for a spare part, and so far I found the pallet fork 710 for the Osco 66 movement in a single web shop, but very expensive. In further research I found that there are lots of pallet forks for different movements with part number "710", and they are a lot cheaper.

I'm wondering whether these pallet forks with the same part number "710" are actually identical and compatible parts. Is that the case? Or is the practice that for different movements the part number of the pallet fork is often "710", and the parts differ from movement to movement?

[tomh207]

The Swiss standardised the base part numbers for movements. You will have lots of movements with the part number 710 and none of them are compatible. 
 

Tom

[caseback]

8 minutes ago, stm said:

Or is the practice that for different movements the part number of the pallet fork is often "710", and the parts differ from movement to movement?

There is a Swiss generic part number system as defined by Ebauches SA. For instance 210 is a third wheel, 710 a pallet fork, 401 winding stem, 410 winding pinion, etc. 

[stm]

Quote

The Swiss standardised the base part numbers for movements. You will have lots of movements with the part number 710 and none of them are compatible. 

Quote

There is a Swiss generic part number system as defined by Ebauches SA. For instance 210 is a third wheel, 710 a pallet fork, 401 winding stem, 410 winding pinion, etc. 

 @tomh207 and @caseback: Thanks for clarifying this, then I will have to bite the bullet and buy the expensive pallet fork.

[Neverenoughwatches]

26 minutes ago, stm said:

 @tomh207 and @caseback: Thanks for clarifying this, then I will have to bite the bullet and buy the expensive pallet fork.

You might pick up the whole movement for less than the lever. I have a restored Osco 66 in an  Ackro branded watch from the 60's  runs well, I think I only paid a few quid for it bundled up jn a joblot.

Looks very much like an st96 to me.

No that isn't correct , the seller has it listed wrong.

[AndyGSi]

You could also look for another movement with the same pallet fork.

Cousins also have this in stock for the Osco 52 based on the above being correct.

[caseback]

might be useful?

 

[JohnR725]

12 hours ago, stm said:

The part number of the pallet fork for this movement is "710" according to the Emmy Watch

the problem with watch parts are there tiny. typically watch parts can come in tiny packages about the size of a postage stamp. This does not give a lot of room for writing. So for instance here's an image I swiped off of eBay we get a symbol we know that it's an ETA part. We have the size of the watch 10 1/2 and the model number. Then the part has a nice box around it so I know it's a 723. We get way more writing than we sometimes find we get all the cross-references we find that there's three in the package and didn't really tiny print we do find it's a balance staff. There is also the other problem notice in the description how many different languages there are? So universally a part number is three digits versus a whole bunch of words and advocates really nicely on a package. Most the time you may not find the words on the package at all just the part number which you might think of as a description number not actually a part number.

 

12 hours ago, stm said:

I broke the axis of the pallet fork.

Ithen I'm assuming you broke the pivot off of the pallet fork arbor? Did you know they pallet fork arbor is a separate component often times replaceable? Although ideally you really need a tool to insert it. Typically jeweling tools will have accessories for pushing it in and adjusting it to the right position.Then pallet fork arbors are interesting because they often will fit a variety of watches not just the family of watches that you're in.

[stm]

23 hours ago, AndyGSi said:

You could also look for another movement with the same pallet fork.

Cousins also have this in stock for the Osco 52 based on the above being correct.

That is valuable information, thanks! I had looked for the part on the Cousin's website, but I didn't find this about the compatible movements that share the same part.

[stm]

12 hours ago, JohnR725 said:

Ithen I'm assuming you broke the pivot off of the pallet fork arbor? Did you know they pallet fork arbor is a separate component often times replaceable? Although ideally you really need a tool to insert it. Typically jeweling tools will have accessories for pushing it in and adjusting it to the right position.Then pallet fork arbors are interesting because they often will fit a variety of watches not just the family of watches that you're in.

You're right, I broke the pivot off the axis, not the axis as a whole. I know that it is theoretically possible to change only the axis, but I'm afraid that this would require a lot of skill in addition to the potentially expensive toolset required for this task.

[stm]

On 12/1/2024 at 11:22 PM, Neverenoughwatches said:

You might pick up the whole movement for less than the lever. I have a restored Osco 66 in an  Ackro branded watch from the 60's  runs well, I think I only paid a few quid for it bundled up jn a joblot.

@Neverenoughwatches You were right. I was able to source a set of two Osco 66 movements for about the price of the single pallet fork, and one of the movements even seems to be in working condition.

[RichardHarris123]

Do you have whole watches or just movements? If you only have movements and one is working, then there's no point in swapping parts. 

[stm]

On 12/13/2024 at 7:36 PM, RichardHarris123 said:

Do you have whole watches or just movements? If you only have movements and one is working, then there's no point in swapping parts. 

I have a whole watch that I tried to service, and then I broke the pivot of the pallet fork. So now I have two extra Osco 66 movements for spare parts, and I'm confident that the pallet fork in one of them is fine because it looks like this other movement is actually working.