DIY Tutorial - Broaching a second hand

[KJ2020]

This isn’t nearly as difficult as it might sound so don’t be afraid to try it. I needed to replace the second hand on my TC Sub and when I went to press it down it just wouldn’t seat. Looking at the post collar hole I could see that it wasn’t as big as the previous one so what the hell? It’s a BP 2824 second hand that I re-lumed to match the TC hands so IDK.

Anyway I didn’t come all this way to go home empty so I dug out the broaching files. This little kit is only like $10 on Ali Express, a little more on Esslinger.com if they are in stock.

Choose a file that you think will work and set the hand hole onto it. This project was super easy because I had the previous hand still so I fit it to the file first and marked the file with a Sharpie where it fell down to.

So I can easily see how much to file out of the hole surround

I didn’t bother with finger cots because the hand will get an ultrasound clean and a wipe down later. I just gently held the tail between thumb and forefinger and worked the file around til the hand fell to the Sharpie mark. You can see the tiny filings on my finger.

Then it’s off to a bath and a blow dry.

Some ROR cleaner on a Zeiss lens cloth for a wipe down

I pick up seconds hands for pressing with a little plastic stick and some bracelet tape. This makes them pretty easy to move around slightly while stabilizing them with the presser tip.

Love it when a job goes along without any major glitches

Happy modding and thanks for looking!

 

[Nur-Uhr]

Amazing tutorial as always !!
WOW - nice job, it looks always "easy going" when you post such things

 

[Karbon74]

genius

 

[ward1991]

Every kj2020 post should just be a sticky. What the hell, give the man his own dang section.

 

[Plaasbaas]

Thanks once more. Very cool thread. I download them all and they have become such a precious compendium.

 

[dogwood]

Great tutorial! I had to do exactly the same recently on a 7750 movement swap. Those little micro-broached are wonderful. I tend to hold the hand in wood tipped tweezers rather than my fingers. But your notes on how to clean up the hand afterwards are excellent. Do you use soapy water in the ultrasonic to remove the oils without harming the lume?

 

[WatchSmith.US]

Great tutorial KJ! I agree you should have a dedicated section for your very informative and well written and photographed tutorials. I did one the other day using my bench block and bracelet tape. Keep ‘em coming brother. Everyone appreciates your efforts.

 

[KJ2020]

Great tutorial! I had to do exactly the same recently on a 7750 movement swap. Those little micro-broached are wonderful. I tend to hold the hand in wood tipped tweezers rather than my fingers. But your notes on how to clean up the hand afterwards are excellent. Do you use soapy water in the ultrasonic to remove the oils without harming the lume?

Yes bro, a couple drops of Dawn dish soap with water in a glass jar is a frequent concoction in my hands work. I nearly always wash and wipe hands before an install if hands aren't new and it has never bothered lume at all.* In fact if there's any slight lume overspill onto the front side of a hand, I need something stronger to get it off. I use an artist's brush with mostly evaporated acetone and ultra light strokes on the unwanted lume. Then back to wash and wipe again.

*I should qualify this - I'm talking about varnish or epoxy based lume like we are normally dealing with, Superluminova and Chromalight. Ofc this is not a technique for water based lume like you can find on some custom vintage dials and hands.

While luming I keep two bowls and two brushes handy. One with acetone and one with alcohol. A botched lume placement on a hand can be immediately reset to square one in under a minute to try again.

 

[KJ2020]

Thanks a lot for the excellent pics of textbook watchmaking examples guys, I'm delighted to have them included here.

Sometimes I tend to be a little more hands on since I totally trust my cleaning techniques.

BTW I use the same cleaning techniques for gloss dials (with water safe lume) and crystals too. Wash, rinse and fast immediate blow drying leaves these parts spotless. Stumbling on this was the 'Dawn' of a new era for me, haha.

 

[WatchSmith.US]

Impressive dial washing, KJ. Sometimes we get some filthy and greasy ones and it can be a struggle using rodico, sticky tips, or alcohol wipe. Your example looks perfect!

 

[Slugger]

Finally! I found a purpose for that Dawn dishwashing soap under the sink. It ruined all my paper plates and Dixie cups!

Years ago, I used alchohol on a swab to “clean” a bluesy dial and it did not go well as the printing was wiped off like it never existed. I‘ve also found Rodico, even fresh from the package, sometimes leaves a weird stickiness. Am I the only one? I use Rodico often but no longer on hands and rarely on dials.