Crown sizing

[rossjackson01]

Hello again. Advice please.

My bride has a watch that she has owned for 50 years. It is not working and she asked me to repair it. 

I've done service on the dead watch and it is now working. Sekonda ladies 17 jewel. Movement marked 256. I am pleased with it. However she has lost the crown. Just the stem was visible. Therefore I need to obtain a crown. My problem is, I don't know how to size correctly. The stem screw size is 0.7.mm. I see averts for various size crowns, but there is no mention for the thread. Can someone help and give me advice please.

2 photographs attached

1. Movement and stem.

2. Movement, stem and case. 

Thank you

Ross

 

[JohnFrum]

“Use the table below to determine the tap size of your watch stem. Measure the diameter the threads on the stem and use the table below to find the corresponding tap size.”

https://blog.esslinger.com/stem-tap-mm-size-cross-reference-chart/

Edited February 15, 2023 by JohnFrum

[rossjackson01]

11 minutes ago, JohnFrum said:

https://blog.esslinger.com/stem-tap-mm-size-cross-reference-chart/

Thank you. I can see it is tap 12. 

Have an equivalent size watch and the crown diameter is 4.5mm. Still not sure how to order

Is this suitable

https://www.ebay.co.uk/itm/125450070995

Edited February 15, 2023 by rossjackson01
more information

[tomh207]

@rossjackson01look here Ross, https://www.cousinsuk.com/product/short-pipe-swiss-italian-ss they have stainless or chrome in the size you are looking for. 99p for chrome, £1.10 for stainless steel +VAT and postage, might be worth putting together an order to make it better for you.

Tom

[rossjackson01]

Tom. Good man you are.

Thank you. Just need to work out number for postage to make it effective. 

Regards

Ross

[tomh207]

@rossjackson01i am putting together an order myself Ross, could bring it forward and add it to mine if you like?

 

Tom

[rossjackson01]

2 minutes ago, tomh207 said:

@rossjackson01i am putting together an order myself Ross, could bring it forward and add it to mine if you like?

 

Tom

What a lovely person you are.  I'm not sure if it would be cost effective for you. I do live quite a way from you. Thank you anyway. 

Regards

Ross

[tomh207]

Probably only an envelope and 1st class stamp mate if you don’t want personal delivery

 

Tom

[rossjackson01]

Tom

Thinking on it. Will let you know. Got a bit of time now that the spring thing is to be sorted. 

Regards

Ross

Edited February 15, 2023 by rossjackson01

[kd8tzc]

I know this is an older thread, but not having seen any help on the Esslinger site, what do they mean by measure the diameter of the threads?  Should I just use a vernier micrometer, and see what the thickness (diameter) of the stem is (possibly that is what they mean by diameter of the threads?  It say 1.15mm, but that is in between tap sizes it appears.

[rossjackson01]

11 hours ago, kd8tzc said:

I know this is an older thread, but not having seen any help on the Esslinger site, what do they mean by measure the diameter of the threads?  Should I just use a vernier micrometer, and see what the thickness (diameter) of the stem is (possibly that is what they mean by diameter of the threads?  It say 1.15mm, but that is in between tap sizes it appears.

By looking at the chart I would go for Tap 7.  I use a cheap digital calliper. Works well for me. I always reset the calliper to zero before measurement. Hope this reply helps.

https://blog.esslinger.com/stem-tap-mm-size-cross-reference-chart/

 

Edited April 14, 2023 by rossjackson01
spelling

[kd8tzc]

Thanks Ross, so it is the thickness (diameter) of the stem then.  Thanks.

[rossjackson01]

On 4/14/2023 at 11:47 AM, kd8tzc said:

Thanks Ross, so it is the thickness (diameter) of the stem then.  Thanks.

Diameter of the thread.

[oldhippy]

Looking at the case you need a dust proof button. This type in chrome