How to Dissolve a Broken Watch Stem in Alum Powder

[@MyRetroWatches]

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[@MidwestHapkido]

Thank you so very much for answering my unasked question. I had been aware of this method for dissolving watch screws from vintage Pocket Watch plates but could not get a clear answer on the role of heat in the process. Boiling the piece in the solution seemed a bit risky but your approach of soaking then adding heat came across as more measured. Again, many thanks.

[@meolemy2006]

I dissolve 4 and 6 mm bolts this way in the aluminum heads of 750 cc twin cylinder Kohler engines. It requires more heat and more alum but I am in agreement that it does indeed soften what you are disolving. Generally I do not dissolve them entirely but makes them quite easy to drill. The process does indeed turn the non ferris metal dark but does not hurt it in any other way. Great video!

[@kiteboardkid]

I have used this method for last 15 years and it really does work and saves buying a new Crown. I leave for at least a week in the solution and then pop it through the ultra sonic cleaner. You will need to re-polish the Crown after.

[@Ha--Le]

IS IT AL2SO4 ? .THANK

[@DirtyPlumbus]

Have to admit I probably wouldn't have ever thought of this. Great video.

[@nellyridel4356]

Learn something new everyday. Thank you for this video .

[@kowaltoboggan]

I must admit that I learn something new every day. Thanks for sharing this knowledge!

[@jipke]

Great to see this works. My watch maker is doing that with the stem of my watch -- which he broke himself during a routine crystal swap & pressure test procedure. Been waiting for my watch for more than a month now. Sorry, had to vent my frustration here ;-)

[@watchmedraw4340]

Many people have alum powder or can get alum powder at pharmacies. This is amazing. This is also something I never heard of.

[@Ha--Le]

IS IT AL2SO4 ? .THANK

[@FabianoSantosArt]

Wow, after I’ve seen your video, I gave it a try and for my surprise, i was able to save a crown (and of course a rare one) that had a piece of stem broken inside for almost 5 years. Thank you so much for your help.

[@MyRetroWatches]

Fantastic news. It does not work on all sadly I think some stems are stainless steel so alum has no effect.

[@FabianoSantosArt]

My Retro Watches, and btw it took only 4 days to dissolve the piece of stem. Thank you once again 😃👍🏼

[@natecharleswatches]

Talk about learning something new everyday, never thought of doing something like this. Great video :)

[@MyRetroWatches]

FunWithFire thanks . Passes the time away right now ...

[@1rightrev]

I was skeptical about the alum working. I mean alum is used when pickling vegetables like pickles! The other aspect of this was the first time I read someone recommending this to dissolve a stem from a crown I thought, seems like a lot of work for a crown. But an Omega crown? Now I get it! Thanks Michael

[@mr22guy]

"pickling vegetables like pickles" I think you mean cucumbers :P

[@CyberRabid.]

Just broke a stem in a Pan style crown. Will definitely try this. Thanx.

[@ValentechTime]

Great video, very helpful. I too have several Zodiac, Nixon, Burberry and other crowns with broken stem pieces stuck inside, so will try to recover those rare crowns. FYI, the stem diameter of 0.9 mm translates to the Tap 10.

[@whatsstefon]

How did you go with yours? I have a friends old Raketa pocket watch here with a broken stem inside the crown. I might try this trick.

[@ValentechTime]

@@whatsstefon Unfortunately, did not have time for that, worked on watches with good crowns. Hopefully, will try this method some time in the future. Is it worth to fix Raketa crowns? My understanding, they could be replaced by general ones.

[@whatsstefon]

@@ValentechTime it’s worth it because of the sentimental value of the watch to my friend.

[@ValentechTime]

@@whatsstefon Understood.

[@tadeubotelho4410]

Thank you for the tip. I have the same issue with a Fossil crown where the stem breaks inside. I will try your expertise here. Wishing you success!

[@Andrew-J316]

Thanks for your best known methods on repairing and restoring watches! Always fun to learn something new!

[@bjoernandersen8287]

Great video, my year 1982 mod. vintage Seiko 7548-700B watch stem just broke in the crown so I will try this trick. Krossing my fingers. Thanks for sharing!.

[@heq65]

Awesome Video! Thank you for putting this process out there, works like a charm. Removed a broken stem from a Casio AD520 broke at the base from the crown.

[@scottwagstaff5121]

Thanks for the tutorial, managed to save the longines I was working in, I managed to break the stem trying to remove the back plate... after a few weeks of dissolving in alum I managed to save the crown and re-use..😁

[@MyRetroWatches]

Glad it helped!

[@garyggarner7738]

Mike I learned something New - as I often do watching Your Videos! Amazing!

[@willemw6642]

Thanks for the tip. I tried it and it works great. Heat will speed up the proces signifficantly.

[@bangy55]

Thanks again, Mr Retro. If I hadn't stumbled across this video I never would have remembered that kilo of alum powder I bought a couple of years ago on eBay. Stashed away in the back of my clothes closet, as I recall. There should be enough left after having used a teaspoon or two to remove a pesky broken barrel bridge screw. I now feel safe to apply a little extra torque to these old 6309 screws that keep coming loose.

[@Ha--Le]

IS IT AL2SO4 ? .THANK

[@iwctoys1]

Great video. Have a Valjoux 7750 with a broken stem inside. Was finally able to remove with a deep crown. Sometime simple solutions are the hardest to figure out.Thanks much.

[@Mymatevince]

Really interesting Mike, I didn't think that would work so quick. Nicely filmed video :-)

[@MyRetroWatches]

Cheers mate.

[@dbzamora]

You can probably immerse the stem which broke off in the jar with the crown to have a visual reference on how the alum is working on dissolving material in the crown. Great video as usual!

[@MyRetroWatches]

Dennis Zamora not a bad idea ! Thanks for watching.

[@usermx977]

Great video advice. Thank you. Will try with my crown and report back with results.

[@usermx977]

Report is ready :). Everythink went as expected/explained. My torn stem fully dissolved and I succesfully managed to reuse original crown on my wife's watch. Let me thank op for his effort to help.

[@francispalmer9737]

Cheers for this. I have a crown with the same problem so I will give it a go.

[@MyRetroWatches]

If it’s stainless steel it won’t work but it’s worth a shot

[@jeff1176]

I had heard you mention this process on other videos, but never seen it done. That worked a treat. I'll have to lock this in the memory bank. Great job Mike.

[@tiberius4177]

Great video, I have buy Some aluminium powder, and it’s working😀 I have a old movement who had a broken screw inside I did what you did, and it’s working, now I can build it together sinds 7 Years. Thanks👍 Keeping up the good work.

[@jeromedenmark7587]

Awesome. Never thought that was possible

[@treetopspider]

Great video as always. I had a similar problem with a Tag watch and tried the Alum trick too. It took about 2 weeks before the stem had dissolved but I recon I could have speeded things up a bit if I had tried your heating trick.

[@antouanp]

Well don......thank you very much for shearing this nice information !!!!!!!!!

[@rossmfifer]

Thanks for that. Also interesting about the tap sizing

[@fraserp2377]

thanks for this, just what i need!

[@eclectarama]

Great video, Mike. Thanks for taking the time to make it. Who knew that this is an option to solve this particularly problem. By the way, I bought one of the boom microscopes and wouldn't be without it now. A complete and utter game-changer. Cheers, Steve.

[@MyRetroWatches]

Steve Speck indeed a microscope is a new world !

[@MrPagecat]

Very helpful video

[@EdwinFisher-c1e]

That was interesting and good in the presentation. just simply get on and do it 😊

[@bushkesh]

Thank you so much for the video. I've got a broken stem in a Seiko 6309 crown. Will try this method out.

[@MyRetroWatches]

BORGSAUCE good luck

[@kiwicory100]

You sir are amazing

[@bauertime]

For 35 years I've been using alum as water treatment operator. I also do watch repair, and have only learned of this in the last year or so.

[@Ha--Le]

IS IT AL2SO4 ? .THANK

[@bauertime]

@@Ha--Le It was, but now we use polyaluminum chloride or pac.

[@BillMrWild]

Thanks Mike, another good one

[@dodgydruid]

I've been lucky until the arrival of my Pulsar YM62-X155 with its unique UFO crown so got some Alum and going to give it a try... cheers Ian

[@omegadun66]

Very informative, I didn't know. thanks

[@MyRetroWatches]

Does not work on all stems. If a stem is stainless steel then it will do nothing. It’s always worth a try though.

[@ThePhoenixlad]

Great Video!! Perfect timing too because I'm just in the middle of trying to solve a similar issue regarding a stem. I'm trying to restore an old German Ebauches Sonceboz ES 54. The description on Ebay just said it doesn't wind up so, I thought I would take a punt on the task of restoring it. When I got it, it appeared to have no stem, I found the remains of it broken off inside the movement. Everything regarding the watch is in good order and works well, I just can't seem to find another stem and crown for it. Your video has helped me to work out what size stem but, I'm struggling to obtain one. With patience I'm sure I will but, if anyone has any clues as to what other stem and crown would/could fit, will be of great appreciation. Thank you again, Great Vid Mike!! :)

[@MyRetroWatches]

Graham Payne good luck. From what I have been told in some countries the tap size is different . So for 0.9mm tap from Elsinger would be Tap 10.. I’m told here in uk it’s mainly the 9 tap .9 mm formula

[@ThePhoenixlad]

@@MyRetroWatches Brilliant! Thanks Mike. I was just about to measure the thread; only to find it had been broken off from the base of the thread, no thread left to measure, what's left of the metal measures .6 so, I'll go with the tap 6 and take it from there. Thank again. Stay Safe Mike.

[@sreenivasankallikunnath5120]

Very good idea sir thanks Im watch maker indian 🙏🏼

[@carloscarvalhido2424]

Excellent idea ! Very useful ! Thanks :)

[@metalman4141]

Spoon on glass ..... lovely

[@dodgydruid]

Gave you an honourable mention in my last vid as cleaning and finishing a Vostok Komandirskie I gave it a thorough clean with some 99.9% Isopropyl Alcohol and it erased the paint off the bezel and did the paint and wipe with me thumb as you did it and looks perfect :) Also showed a very nice Epson branded chrono with the 7T92A Seiko chrono movement in. Am working on sterilising my 090 Amphibia's dial with the same IPA leaving a high gloss dial is looking good.

[@dodgydruid]

I wished I knew the alum trick back when I tried fixing my 1985 Vespa's gear shifter where the switch screw had snapped, attempts to drill out the hardened steel screw shaft ended up with a wrecked left handlebar section and it took me 2 years to find a replacement as it was a unique part for this model of quite rare Vespa when if I had done the alum trick it would have been original and hassle free.

[@future_design23]

This video help me a lot thank you Mike

[@MyRetroWatches]

Vlatko Bumbaroski your welcome . Thanks for watching.

[@cristobalosuna3106]

Thank you for sharing!

[@johncunningham5435]

Nice tip!

[@metalman4141]

Good one 👍

[@AstonColey]

Wondering if putting the jar in an ultra sonic bath would speed it up? I've got one to do so I'll try it.

[@MyRetroWatches]

It can do but not by the ultrasonic waves just the heat.

[@TheTarrMan]

Cool trick, thanks for sharing.

[@dyoung3877]

I used this process on a Benrus gg-w-113 that had a broken split stem . The key is to put as much alum as the water will hold and use heat. I used a coffee warmer plate . (Room temperature water is not very effective.) In the US alum can be purchased where you would buy canning products to home can vegetables.

[@MyRetroWatches]

D Young how long did it take to dissolve on the coffee plate?

[@dyoung3877]

@@MyRetroWatches about a day after I fugured it out. I was using a shot glass to limit amount of alum needed to make it really high consentrated . The water would evaporate quickly. If you would use a baby food jar and maybe keep it covered it would reduce evaporation. Just keep an eye on it. Good luck.

[@MyRetroWatches]

D Young thanks for that. I’m going to find a broken crown and try it in my ultrasonic

[@lobdsk]

I got to get some alum powder amazing

[@alexanderr.1801]

thanks for this video, i recently bought my first mechanical watch, its a Seagull 1963 because you know its my first and its cheap but has an appeal to it... so long story short i had it for about 3 weeks and the crown broke of because its made out of chinesium and not steal so i ordered a new stem witch was difficult enough and while i wait for my order i try to salvage the crown wich has a nice star on it an gives the watch a nice touch .... so heres to hoping the crown isnt also made from chinesium and wont dissolve with the stem :-D .... but anyway thanks for the video this has already been a huge help

[@MyRetroWatches]

Sorry to hear of your stem troubles. Cousins sell the stems for these apparently. I think the alum will be okay for you. It’s stainless it has no effect on.

[@andersmmvfc.8376]

You are back :D thank you for the entertainment!

[@a.aguilar]

Great tip! Alum is used on some deodorants, and here in my country I did buy an alum stick deodorant that I use to prepare the "beverage". Sometimes it could be used to disolve broken screws on some mainplates too, as long as you can take out any other steel component. I tried on a 6309 movement and the screw got dissolved in a couple of weeks, but also the post for the setting wheel lever and the minute wheel bridge disappeared 🤢 so be careful with that. Stay healthy.

[@MyRetroWatches]

Thanks. I think it can only be safely used on stainless.

[@johnpinner1]

Good to see you my friend stay safe

[@MyRetroWatches]

John Pinner thanks. You too

[@brianwilliamson388]

Just helped me Pal, thanks so much. I have an Oris with that very problem. Skint, so ile give this a go. Thanks again . BB [Q- What would neutralize the Alum Powder i wonder].

[@jacoboakley7108]

Hi Mike - thanks for the vid. I meant to do one about alum, but I have no followers. The trick here is to add as much powder as will dissolve in the water. Keep it on a double boiler and you should be able to dissolve a screw in a few hours. You can do this for screws broken off in a plate as well, but be sure to avoid dissolving any pins which may be pressed in.

[@adrianbirkett594]

That's amazing!, great tip. Thanks Michael. Just to say, be careful of post coming through letter box, it can carry the virus. Leave for at least 24 hrs or wear gloves. 👍 Be safe. Adrian

[@MyRetroWatches]

Adrian Birkett thansk pal. Nothing in the post right now but yes safety first..

[@gurudutt4746]

🇬🇧 Hi from UK 🇬🇧 👍❤❤👍 That's fantastic.... A great Video - and as usual, very helpful...✔ (Stay safe bro...🙂🙂🙂🙂) 🇬🇧 Thanks from UK 🇬🇧

[@universesorion6501]

Cool video

[@concho22]

Amazing. But how would it go with a gold plated crown?

[@MyRetroWatches]

@@concho22 fine. Does not remove plating. The stem will only dissolve if it’s not stainless steel .

[@concho22]

@MyRetroWatches how do i know if it's stainless steel under the gold plate? It's a raymond weil from 2018, cost new £800.

[@MyRetroWatches]

@ I mean the stem. Crowns will be stainless or sometimes brass. This stuff is harmless and it’s used in food and deodorants! Just has some reaction with iron . I did a recent video with a Gerrard watch where I have to dissolve from a gold crown. Rust The Watchmakers Enemy- Garrard Watch Restoration kzbin.info/www/bejne/fYS8goGkj5KAhKc

[@concho22]

@MyRetroWatches excellent, many thanks for the help. Your channel is superb, very helpful. I've just started restoring and selling stuff. it's going well. I'm leaning all the time.

[@electromech8931]

sir..! which camera you , used for your videography?

[@dingdong6259]

great video! would you recommend this method for a chrome plated brass crown (heuer 7700)?

[@bxpress6507]

I notice the crystalline formations around the waterproof seal area and inside the crown stem..I notice was stuck to outside of crown but comes off easy..looked like most of watch stem did dissolve..just need .7mm rod to knock off the crystalline debris

[@willacewallace5905]

One cup battery acid (phosphoric acid), half cup water, 12 spoons of alum. Mix the heated water and acid solution shy of boiling then add alum stirring to saturate. Keep solution at 200 degrees with suspect part submerged. Use either an aluminum pot or glass heat safe dish. This works on steel stuck in aluminium, high grade stainless, brass, copper.

[@MyRetroWatches]

Thanks , one big recipe but if it works!

[@willacewallace5905]

You're welcome. For small items such as broken 6-32 taps works in a matter of a few hours. Imagine #9 and #10 broken stem portions rather quickly! For small parts, even used a sonic jewelry cleaner with hot solution in it.

[@luked2767]

Same thing just happened to my orient Kamasu, I've had it since it came out but its JDM and I wore it on my wedding and love it. It broke in sich a way the only way to take it out physically would be using a mini broken bolt remover, I have never replaced the stem of a watch so I know I will need some clippers, a micrometer and a fine file, not sure if I could use the clippers on my leather man's pliers? I plan to remove the oring then heat it with alum in a Pyrex jug and stir, it looks like you need something to clean out the residue. What brand of alum powder did you use? I know some dont work, I hope it won't remove the lazer engraved signed crown. You can use other things to dissolve ferrous metals but I think they must make stems out of a standard metal just for this type of thing as before it would be plated bronze but now many are stainless steel so I think the anti corrosion of SS with chromium especially in 316L maybe it would take alum a very long time to touch. I realy appreciate the video. Thankfully less than a year ago orient is selling 2 movements under the Seiko Epson brand to 3rd party manufacturers YN56A exactly the same as the F6922 day date like in the Kamasu and others and the YN55A the date only version. They are made in Japan in the same factory just a different rotor engraving. Ironically the hand sizes, size of the movement and such are the same as the NH35 /36 but since the output in Malaysia of these popular movement are low orient fibaly started selling them, you could swap out any NH35/36 watch with one sameish size, the timograph angle is 1 degree different but made in Japan and the steel seems to be harder compared to seiko. They are quite a bit more accurate than the NH30 series and you just have to look at them for the rotor to move but since they are 21 jewels some say they are no good, if its a ni directional rotor and using the magic lever system then you only need 4 jewels for the auto works.

[@MivMusseStudios]

just ordered a bag of alum powder to see if it will desolve the bezel click ball of a 6309-7040 that has been rusted in place and bothering me for a while now. it could just be the answer to this know problem with vintage seiko divers. Thank you for the tip :D

[@Ha--Le]

IS IT AL2SO4 ? .THANK

[@barstatar4246]

Does it make it any safer to paint the crown with nail polish beforehand, I wonder. Or, is it being too cautious?

[@MyRetroWatches]

should not make a difference. This powder is used in cooking etc so its not harmful it just can slowly dissolve ferrous metals but not stainless. It does not work on all stems.

[@agp548]

Hi mike the seiko crown I have has a rubber washer on it do I need to take that off before I use the powder I was thinking it might dissolve tho washer.

[@MyRetroWatches]

no . problem you may have is most Seiko stems are stainless steel and the alum will do nothing to dissolve it sadly..

[@agp548]

@@MyRetroWatches it worked took a while had to apply heat every day. Thanks for your help

[@Inkreptile]

Hmmm this is pure witchcraft!!! Might try this later on a crown I have... I wil make a post when that happens!

[@robincornish1769]

It's not witchcraft, it's pure science (chemistry). "Any technology sufficiently advanced when first encountered appears to be magic." Don't know who that quote comes from.

[@MywatchKaki]

How long should i boil the alum powder solution with the item inside? unfortunately, stem inside crown has not show any signs of breaking down after 3 days of being submerged... am i doing something wrong?

[@MyRetroWatches]

It’s not guaranteed, I think after 3 days the likelihood is the stem is stainless steel which will not dissolve in alum. Alum will only work on basic steel .

[@johnl798]

I have a similar problem even got tiny drill bits and all the rest of it . Haven't done it yet . The crown I have is black will the alum strip the colour off the crown ? As I might just try this as it looks safer . Less chance of mucking it up .

[@MyRetroWatches]

I can’t say for certain but alum is used in food so in context it’s harmless. It does not do anything to gaskets either. I would surmise it will be fine on plating .

[@bslbsl6040]

Hi, i have a blancpain villeret 40mm watch in stainless steel 2 years old (2020) watch and i noticed that it is stiff when i try to wind it. It has 72 hours power reserve. Example: When i wind it, it is tight.. I have to pull out the crown then i have to push it back in, in order for it to be buttery smooth when i wind it. It keeps excellent time BUT it is just stiff/tight if i wind it without pulling out the crown and pushing it back in first.. feels like resistance.. Any idea on what could it be? I dont have warranty. My jlc reverso is so smooth , i dont have to pull out crown and push back in for it to be smooth wind. Which type of silicone/oil for the crown gasket do you recommend?

[@christophernalbone6299]

I would have drill a hole in the stem with a smaller diameter drill bit then insert a copper wire and heated the wire with a soldering iron to soften the thread locking compound. Take a push pin and grind it into a shape of a bolt extractor with a dremel tool. Tap the push pin in. Then unscrewed the broken stem. Anyway your video was interesting and another good idea.

[@oscillon]

I have a Seiko 6105 with a very grubby click ball. I wonder if this would work without changing the finish on the case.

[@MyRetroWatches]

Daniel Blair now there’s a question . One I can’t really answer. Seems to be fine on stainless , the crown is still the same bright finish. On a case I’d worry about the stem tube as that’s possibly another material ( not sure though. Equally the ball might dissolve unless that’s what you are trying to do.

[@oscillon]

@@MyRetroWatches I thought about the stem tube too. I think what I'd do is only submerge the smallest possible portion of the case around the 2:00 position, where the click ball and spring live. I assume it's a steel ball as it's terribly corroded and broken.

[@ethantaylor5514]

I'm curious, did the Alum powder also corrode the o-ring in the crown?

[@Inkreptile]

I'll look into that

[@Inkreptile]

Pretty sure it doesn't but don't take my word for it

[@jagathmithya719]

I have the exact problem with an omega crown. Just placed the order for the Alum powder. Hope it works for me too. Thanks a lot. Btw I am having difficulty locating a omega stem for the Seamaster. Do numbers like 1010, or 42, or 344845 mean anything? Any help will be much appreciated.

[@DuncanGlendinning]

Another nugget - thanks! I have a question for which you might have a suggestion. I am looking for plastic c clips for the pushers on my Citizen Navihawk (C300). I have been searching with no luck. Any ideas? Thanks!

[@MyRetroWatches]

Duncan Glendinning not sure to be honest never seen plastic ones however search for E clips rather than C , many Seikos use e clips and you find them in very small sizes., I bought an assorted pack a long time ago ironically most have been too small for me to use!

[@DuncanGlendinning]

@@MyRetroWatches thanks - I'll check them out!

[@yoBradyO11]

Do you know if this method will dissolve brass and gaskets? I just had the same situation with a Seiko crown and I noticed that the stem plunger mechanism is made out of brass

[@MyRetroWatches]

Gaskets it won’t eat. To be fair I don’t think It would touch brass either. I would assume it’s only ferrous metals. That said stainless is Ferrous but it has no effect. To note that I’ve had 50/50 success with Seiko as I think some of their stems are made with stainless and don’t dissolve

[@fernandoAveledo]

Great video as always. I wonder why this method did not cause damages to the rest of the crown but to the broken stem...

[@MyRetroWatches]

because the crown is stainless and the stem is a mild steel. I have tried this (since filming) on some other crowns and it did not dissolve them as the stem is also stainless..

[@fernandoAveledo]

My Retro Watches Thanks for your reply!

[@Biffo1262]

Put some heat shrink tubing on a spare set of tweezers to help with grip. It works. As for using a Vernier for such small measurements then good luck. I find a micrometer far more accurate and is much easier to use.

[@MyRetroWatches]

Hi I agree with using a micrometer, my mic is on my desk at work and im trapped at home... Vernier is good enough for 0.1mm increments.

[@Kali_Kali]

What is the type of alum? Aluminum potassium sulfate AlK(SO4)2 or Ammonium aluminum sulfate NH4Al(SO4)2

[@MyRetroWatches]

I don’t know . The link to the one I used is in the description of the video

[@Kali_Kali]

@@MyRetroWatches I asked what alum it was because it didn't work for me. I have 100% alum from the drugstore, but with an antiperspirant stick 😁 I thought it was bad alum. But everything was fine. You just had to heat the solution to the right temperature. For me, it started to work at a solution temperature above 83 ℃ (~182 ℉). At higher temperatures, the reaction was faster. I had 300 ml of the solution (55 g of alum, the rest was water). Removing of the 1.5 mm setting stem took several hours.

[@MyRetroWatches]

@@Kali_Kali if the stem is stainless steel it will never dissolve

[@semirXLVII]

Great, but how does it dissolve the stem but not the crown? Isn't the crown steel too? Thanks

[@MyRetroWatches]

I am not a metallurgist but the crown it stainless and the stem normal steel. Stainless must be that bit more resistant to this chemical reaction.

[@semirXLVII]

@@MyRetroWatches I see, that's interesting, thanks for your reply! I knew this method for removing broken screws from the mainplate, which is usually brass, but never heard on crowns. Best regards!

[@jco1298]

That’s really interesting. Great save. Making any headway on the Zodiac?

[@MyRetroWatches]

J Co zodiac balance is with a watchmaker friend putting a new impulse jewel on. Now we are all on lockdown I don’t expect to see this now for ages sadly.

[@dineshjain6770]

Which powder you had used

[@MyRetroWatches]

alum powder . I show the packet in the video and there is a link in the description.

[@RoryMacdonald-pfff]

Hi Michael - well done on preserving and getting it out. Have you tried this with Seiko stems? I’m wrestling with a snapped stem in a nice signed crown (hence I want to save it) and not seeing any ‘progress’ with Alum (good concentration/temperature). I did see Adrian at VTA comment in a video that this approach doesn’t typically work with Seiko stems as they use same/similar steel to the crown. Just wondering what your own experience was on Seiko stems, if you’ve been unfortunate enough. 👍

[@MyRetroWatches]

Yes Seiko genuine stems are stainless and will not dissolve . I’ve found the only way to remove them is to drill them out and re-tap them hole

[@watchandjewelryloft4713]

Just found your post. After soaking a Seiko 5 crown for several days. Wondering why nothing was happening. 😂

[@bmw128racer]

It might've been easier to track the progress if you rinsed out the alum from the crown each time. Heating the solution with the crown speeds up the chemical reaction in dissolving the broken stem.

[@freakysteve140281]

You could probably use a sous vide in a water bath and keep the jar with the alum powder solution hot in that.

[@SideWalkAstronomyNetherlands]

:) Still paging through all the videos checking if I forgot to like any :)

[@MyRetroWatches]

You're the best!

[@timlangel6211]

I wonder what this would do to a screw down crown.

[@MyRetroWatches]

All depends, if the crown is stainless alum is not effective so would do nothing to the crown

[@timlangel6211]

My Retro Watches I am testing this now. The crown is stainless but I’m curious whether the solution will make its way in and dissolve the spring mechanism.

[@hlwhlw4050]

alum all the way

[@drkujavec]

If you dissolve the alum in concentrated citric acid and create a concentrated mixture that you keep at a constant temperature of 75 degrees or more (I use a coffee cup warmer), the alum dissolves MUCH faster.

[@standolfo]

What if the crown is made of gold?

[@MyRetroWatches]

I think it would be fine.

[@robincornish1769]

Gold will be perfectly safe, as it only dissolves in 'aqua regia' which is a far, far stronger acid than alum.

[@kevgermany]

Same alum technique is used for removing corroded in steel parts on instruments like saxophones. Not a fast process.

[@frankyw8803]

Think , I might have tried drill I fine hole down through the middle .

[@MyRetroWatches]

This is how many pro's do it, however I do not own a lathe or a small enough drill. Added to this the Omega watch its from is not mine either but one I am fixing for someone.

[@bjoernandersen8287]

I tried this procedure on my Seiko divers 150m from the 80's but it didn't work. 2-3 weeks with Alum powder, added more powder and waited another 3 week, the broken stem is still stuck in the crown.

[@MyRetroWatches]

All Seiko stems are stainless steel and can’t be dissolved. You will have to drill it out if you want to save your crown.