How to Size Any Watch Mainspring to a Barrel

[@ptchan5]

There is a reason why I signed up for your watchmaker course. You produce content others just gloss over. Thanks Alex.

[@watchrepairtutorials]

This is a problem that we all face sooner or later.

[@WatchWithMike]

Here's why this video is awesome: I purchased a mainspring from a company that listed replacement springs 'by brand + movement number'. The spring I received was the wrong size. I re-watched this video and had the confidence to size the correct replacement mainspring, based on the barrel dimensions. (It's much different than what they sent!) Knowledge is power - thank you, Alex, for sharing the knowledge!

[@watchrepairtutorials]

You got it Mike.

[@johnleonard3806]

Great content again. Your confidence building closing statement " ... is going to make you a better watchmaker", will be remembered as a "classic" someday.

[@watchrepairtutorials]

Hope so. It is really what its all about for me. Helping people become better watchmakers.

[@chuckfinley3542]

I can’t tell you the number of times I’ve acquired vintage watches that have come with entirely wrong mainsprings. In my rookie days, I would dutifully order a replacement mainspring by measuring the width, thickness & length of the old spring, punch in the numbers at CousinsUK and then wonder why the watch still ran poorly. I learned more from my mistakes than my successes.

[@watchrepairtutorials]

I know people don't like to do this, but sometimes it might take 2 or three attempts to find the right spring for a movement.

[@HeliBenj]

Short, to the point and packed with nuggets of information. Again. Glad to see your channel is slowly but surely picking up steam, well deserved for all you bring to this great hobby. The joy of getting knowledge that I can apply and gradually getting better is invaluable, thank you so much Alex

[@watchrepairtutorials]

Much appreciated Ben. Slow and steady. Thanks again

[@hisstorymn]

Sir you are an inspiration for us amateurs! Thank you for your instruction.

[@watchrepairtutorials]

So nice of you. You are very welcome.

[@TropicalSpeed]

This is very good stuff. It answers allot of questions that I had hanging but didn't quite know how to ask. FYi: I replaced the mainspring in a Waltham 620 that has an amplitude problem. I ordered a new, generic, Swiss mainspring after measuring the 620's mainspring and concluded that it did not fill those barrel minimums mentioned in the video. Also, I was able to order the correct size mainspring after watching the video and got it right the first time. Now the the amplitude is good.

[@watchrepairtutorials]

Hey man, Thanks for the feedback. Good to hear from someone putting this information to use. Good results, Perfect!

[@tomholloway7566]

Thanks again Alex, informative as always. Good to see the channel growing so well too.

[@watchrepairtutorials]

Much appreciated Tom. Thanks to guys like you. Even if I hit 100k one day, I will always remember the guys who were here first.

[@mikebruegger8654]

Very important indeed to have the knowledge on how to figure out a comparable spring to the original for vintage movements.

[@watchrepairtutorials]

Yes indeed Mike. Great minds think alike.😊

[@MichaelB-qx1eh]

This is so great, thank you. I'm struggling right now with a UTC movement that is knocking, hits 360deg even at a very low wind and I've been gathering info to replace the spring appropriately. This is so timely, I really appreciate it.

[@watchrepairtutorials]

There you go. That’s one possible solution

[@treetopspider]

Your lessons here are so good. Ive almost watched them all. You make everything so simple to understand. Thank you for all your good work

[@watchrepairtutorials]

Oh man, I appreciate that brother.

[@MrTerrierLove]

This is was a gem of a video to find! I've just taken apart and cleaned 2 Elgin and Omega pocketwatches and am about to order the new springs. I am a novice but have replaced a few. Your superb method and brilliantly explained video is a revelation after some of the shenanigans I've employed to get measurements 😁

[@watchrepairtutorials]

Glad I could help!

[@BradMeehan]

Not only is the content great, but your video production is really evolving with every video.

[@watchrepairtutorials]

I appreciate that Brad.

[@Qwertz77]

Thanks a lot for all the knowledge! Great videos! How to spec main spring video…. Important, easy to Unterstand, easy to apply 👍

[@watchrepairtutorials]

So nice of you. Thanks Stefan

[@steinskotmyr2194]

I simply love your tutorials and explanations. It’s not difficult to understand that you have an ocean of experience and knowledge under the belt. I have learned a lot watching your videos with great satisfaction.

[@watchrepairtutorials]

Wow, thank you Stein. I am so glad you get what I'm doing here

[@roadshowautosports]

You got my subscribe at the “ID of the barrel divided by 87” I’m an apprentice without a master and it was super helpful to know these little details on the how to get to a better result. Thank you!

[@watchrepairtutorials]

I’ll be your Mentor Edson.

[@paulofdirt538]

Subed a week ago and learned more in that time then a year on any other KZbin channel. Finally one for the little guy.

[@watchrepairtutorials]

You are not a little guy to my brother

[@rossjackson3670]

Thank you Alex. Once again you seem to have pre-empted the learning scale of us beginners. Learning for me is two fold. Gain knowledge, which is by progression from one level to the next, understanding that level to allow the progression. I have great difficulty understanding the written word to assimilate. Show me, talk to me and I will remember and understand a great deal. Each video is an increase in the depth. Again. Thank you

[@watchrepairtutorials]

My pleasure Ross. I appreciate you hanging out with me.

[@yizhang9051]

I've watch many of your videos, they are high quality, informative. They brought me into the watchmaking hobby! And this hobby made me so happy on many weekends! Thank you so much for distributing the knowledge and fun!!!

[@watchrepairtutorials]

Awesome, thank you!

[@itzhaccroitoru4082]

thanks for this Alex, I'm struggling with mainsprings.Good to see the channel

[@watchrepairtutorials]

Happy to help!

[@khronosbest9448]

Thanks again Alex for the insight and the instruction. My take away here is that for any watch im working on, my replacing the old with the new would be a wise first step.

[@watchrepairtutorials]

On vintage watches it’s almost always the best choice

[@AdamSmith-du1qr]

Wow thanks for this Alex, so informative. I tend to work on non-jeweled pin pallet movements as a hobbyist where getting a good amplitude is always going to be a problem but you have given me the confidence and knowledge to experiment, thank you!👍

[@watchrepairtutorials]

Adam, what you just said is the point of the whole video. Don’t be scared to experiment. It’s a watch, not brain surgery. 😜

[@johnhannon]

Thanks for this Alex! I should now be able to source a close mainspring size for a 60's Seiko 6602B movement I have had trouble locating.

[@watchrepairtutorials]

That’s great John. I have another video coming up about how to modify the length of a main spring which you’ll probably find interesting.

[@MikeSweeneyMedia]

I love working on the Seiko 4006 series.. and yes, virtually everyone I have touched is a "frankenwatch" at this point in the game. My current is a watch where it had been half way disassembled and left for dead. the very best kind of learning experience ;D mainspings seem to be a weak point and I love these mainspring videos you have done. Thank you!

[@watchrepairtutorials]

Thanks Mike. There are plenty of them available for very reasonable prices. They are a troubleshooting juggernaut because you never know what they have done to get them running.

[@alterhype]

Got my first non runner working today thanks to your videos! Seiko 7002 not running for 10 years started moving today. Amplitude weak. Convinced main spring is weak. I’m sure many of us would love if you did a very detailed how to video for winders for both left and right mainsprings.

[@watchrepairtutorials]

I’ve done a little bit on Main Spring winders, what specifically would you like to see?

[@alterhype]

@@watchrepairtutorials just a more detailed how to of right wind vs left wind and how to do it so they go into the barrel in the correct fashion. LOVE the channel.

[@stevefeeney6156]

I just ran to my notebook to write down that formula. Thank you again Alex. 😊

[@watchrepairtutorials]

No worries Steve

[@SkyBlue-le7cd]

Hope that you are well and thanks for the video, Alex. Super useful - am working on an HMT and screwed up the mainspring. After watching the video, I now know what I need to order. (The old mainspring was too small.) Looked at a number of sites and Cousins seems to have the most stock. Again, really appreciate your help. -Victor

[@watchrepairtutorials]

Thank you Victor. Glad it was of some help.

[@brunotulliani]

Simply awesome and thank-you so much again!

[@watchrepairtutorials]

Thank you too Bruno.

[@paulschumacker9901]

Really useful information. I have a vintage American pocket watch that runs out of steam after 12 hours. I’m thinking that the last person to replace the mainspring put one in that was too short. Now I know how to check to see if this is the right size or not! Many thanks!

[@watchrepairtutorials]

Good you hear from you Paul. Thanks my friend

[@frankowot4]

Exactly the subject I needed for a watch I'm working on, thanks.

[@watchrepairtutorials]

Perfect FrankO. Timing is everything.

[@andyshap]

Excellent video! This one goes in the "save" list!

[@watchrepairtutorials]

Awesome, thank you Andy

[@tundeogida9740]

Thanks so much for this video, packed full of knowledge.

[@watchrepairtutorials]

Very welcome!

[@WatchWithMike]

OK, I'm going to break my personal rule of posting before I actually watch the video… Not more than 10 minutes ago I placed my first order with cousins UK for two main springs for watches I am servicing, the first time I have ever purchased a spring. Now I will watch your video and keep my fingers crossed that I didn't majorly screw up! 😂😂😂

[@watchrepairtutorials]

LOL . Let me know how the shipping goes. There are lots of problems with Royal Mail right now.

[@WatchWithMike]

@@watchrepairtutorials Uh-oh! 😮

[@WatchWithMike]

@@watchrepairtutorials hi Alex, royal mail package arrived yesterday, total delivery time of nine days. Not bad for $7.00 economy shipping from England to Philadelphia! 😁

[@thewatchsmith2773]

@@WatchWithMike that’s great to hear. Thanks buddy

[@robertproctor198]

Great video with lots of information. Thanks

[@watchrepairtutorials]

Glad it was helpful Robert.

[@kayakuprising5914]

Awesome info! Thank you.

[@watchrepairtutorials]

I hope you can use it sometime.

[@watchrepairtutorials]

✨✨ Get Your Copy of my eBook, The Secrets for Adjusting Watch Rates ✨✨ ➡➡PDF DOWNLOAD watchrepairtutorials.com/ebook/ ⬅⬅ ➡➡Available on Kindle & Soft Cover @ geni.us/4x8C (Amazon) ✨✨Watchmaking Courses and Training ✨✨ ➡➡ watchrepairtutorials.com/watchmaker-course/ ⬅⬅

[@walther9161]

Awesome stuff Alex!!! Thank you posting!

[@watchrepairtutorials]

No worries Walther. How you been bud?

[@BaldortheHapless]

Thank you, Alex.

[@watchrepairtutorials]

You are very welcome my friend 🤙

[@kuongsam2314]

Thanks for this lesson. How to measure the length of the mainspring without straightening it.

[@watchrepairtutorials]

It is the inside barrel dimension times 35 or 30 depending on what you are working on.

[@felizuleta]

suuuuper helpful video, thanks!

[@watchrepairtutorials]

I just had someone contact me about a movement knocking. They were using a size that they found from someone on the internet. When he used the formula in the video, it became apparent that the strength of the mainspring he had purchased was too strong for the movement.

[@felizuleta]

@@watchrepairtutorials Cool! in the NIHSg 12-02 standard im following for the movement Im working on, theres no clarity on the width, thickness and length, so this is definitely a great guide! I also asked ChatGPT4o about it, it certainly approved, it compared it to another approach for both automatic and non-automatic, and favored this one, 😃 so indeed thank you!

[@pastalavista5754]

Exactly the information I was looking for! Subscribe button smashed. Thank you 🙏

[@watchrepairtutorials]

Thanks for the sub!

[@sandorfulop9352]

Thank you Sir! A great video again!

[@watchrepairtutorials]

Thanks Sandor

[@MrJcubson]

This guy is amazing

[@watchrepairtutorials]

Thank you sir. I hope it helps.

[@JensGrigull-ij6fd]

Good advice.

[@watchrepairtutorials]

Thanks for watching!

[@guyanckaerts9369]

By the way your stream is fantastic and super helpfull!

[@watchrepairtutorials]

Glad to hear it Guy.

[@andrewwebster437]

Another great video and very useful, if you can do the same for hairsprings that would be great. Absolutely great set of videos each packed with useful information.

[@watchrepairtutorials]

Hairspring replacement will always be a near impossible feat. Sad but true

[@andrewrowland7640]

Great video, thank you.

[@watchrepairtutorials]

Glad you liked it Andrew

[@kswaminathan5439]

Sir, I am amazed at the knowledge you possess on watch maintenence. Can you let me know how to find out if the mainspring has become weak and needs replacement? To the naked eye, the mainspring seems ok. But when you assemble the watch, the balance wheel does not swing as freely as it should because power to the escapement is very, very low. Please guide me on this. Thank you very much. God bless you.

[@watchrepairtutorials]

One of the things I always do when servicing a vintage watch is replace the mainspring. A lot of people will reuse the existing mainspring and then run into amplitude issues. So the first thing I would do is put in a new one. Then if the amplitude is still lower than it should be you must reinspect everything. You have to start with the basics and make sure that everything in the power train is correct, the mainspring barrel is correct, the escapement is correct and that the lubrication is done correctly. Once you know 100% that those area's are the way they should be then you can start looking at the mainspring size.

[@kswaminathan5439]

Thank you so much for the crystal-clear explanation.

[@keithstarling8244]

Another great video Alix, are all mainspring the same material. Thank you.

[@watchrepairtutorials]

No, There have been many changes from the old carbon steel mainsprings. Many companies have come up with their own proprietary steel blends.

[@MrGalenlcox]

So helpful man!

[@watchrepairtutorials]

My pleasure. Hope to see you again

[@MrGalenlcox]

@@watchrepairtutorials The hairspring video helped me a lot. Found in one place that is touching on itself. And yes over oil right 100 percent!

[@TimTellsTime]

Another fantastic video. What about some safety barrels where the spring comes above the top of the barrel and there isn't a snap on lid? Waltham for example. How would you do the height on these?

[@watchrepairtutorials]

the best way is to figure out what was there which is easy for Waltham. You are not really going to want to change width very much at all.

[@jorgeluislopezherrera4166]

excelente tutorial, aveces los numeros reales empiesan a fallar para las cuerdas que se fatigan por el rompimiento de su estructura atomica y ahi es cuando vemos esa amplitud baja en la marcha de un reloj teniendo un tren motriz y mecanismo regulador perfectos, a lo cual ando buscando una herramienta que me permita medir la energia potencial elastica real de la cuerda o el par de torcion o torque real que ejerce el barrilete sobre un piñon x ya sea rueda central o rueda primera.

[@watchrepairtutorials]

Thanks 🙏

[@Supercruze]

Fantastic Information.

[@watchrepairtutorials]

Thanks Brother

[@gvmcd]

Another hugely informative video, thank you for posting these. I have a vintage automatic with a seperate sliding bridle piece which forms just over 1 coil against the inside wall of the barrel when fitted. In this case would you measure the inside diameter of the fitted bridle, or still just use the I.D. of the barrel itself?

[@watchrepairtutorials]

I would figure everything just the same. The fact that it's 2 pieces shouldn't matter.

[@timmienorrie]

Superb. Many thanks.

[@watchrepairtutorials]

Most welcome.

[@lobdsk]

I hope this question isn’t too stupid. So when ordering a new mainspring it’s Width x strength x length. Or does it even matter

[@tracymcknight8978]

Love your video's. I'm new to the hobby, and searching for a winding set. Bergeon winders are to costly for me. My question to you is, in your experience, what is the percentage of mainsprings that are left hand wound? It appears that probably 90 percent of them are right hand? Im only working on wristwatch movements for now.

[@watchrepairtutorials]

Most Japanese movements are left and Swiss are right. Most but not all.

[@joechambers4877]

Hi Alex massive fan of the channel! Really helpful video ! I was also wondering once the correct mainspring has been chosen how do you chose the correct mainspring winder. I’m looking to buy them individually. Best wishes, Joe

[@watchrepairtutorials]

If you are buying new mainsprings, you don’t need one. The sizes you DO buy will depend on what you typically work on. For individual sizes look at Esslinger. They list the sizes for each winder.

[@julianramirez6847]

Well , you got the reason on what you said, but if I work on a watch with cero experience , and with no proper tools that will make me even more unsure.

[@watchrepairtutorials]

You are probably right. This may not be for you.

[@jergarmar]

How does the length of a mainspring affect its performance? The width and strength are pretty intuitive, so if I get that wrong I should be able to troubleshoot it. But if I use this formula for an unknown movement, and the mainspring ends up being significantly longer or shorter than the original, is there a problem I might run into, or a particular symptom I should look out for?

[@watchrepairtutorials]

The length is power reserve or how long the watch will run before stopping. The formula will get you close to the length, but obviously it matters what's available to buy. If I had to error on the shorter side. Toolong will result in too little amplitude in most cases.

[@JDRichard]

What is the gauge you are using that allows you to measure the barrel depth

[@watchrepairtutorials]

Just regular calipers

[@MrJosiahCochran]

How do you know what size mainspring winder to use? Since you could technically wind it to a diameter 2/3 of the barrel diameter, if I have a pocket watch with a 14mm barrel could I wind it down to 11mm with one of the K&D adjustable winders, or could that cause damage when inserting it? I’m trying to find the cheapest option to cover all my bases and the adjustable k&d winders cover 4mm to 11mm if you get all 3.

[@watchrepairtutorials]

As long as you can get the winding stem out you should be ok.

[@markcalvillo9572]

Is this the same formula for vintage watches

[@watchrepairtutorials]

These formulas are mostly used when you can't find or actually measure a vintage MS. This information is readily available for modern calipers.

[@guyanckaerts9369]

Hello Alex, do you also have advice for sizing the mainspring for an open barrel from an old pocket watch?

[@watchrepairtutorials]

A barrel is a barrel. You can apply this to virtually any situation.

[@Qwertz77]

Could you give me a hint how to measure the length of a main spring? I wonder whether I could pull it to it‘s full lengh and measure?

[@watchrepairtutorials]

Thats is fine as long as you don't need to re-use it.

[@GardenBearJake]

This tutorial on how to measure the mainspring is fantastic, I just can't find any place online to use this information to order the main spring once I've gathered all the information needed. I can't find any forums or information regarding where or how to order the part needed specifically. The biggest hurdle to my watch repairing hobby is finding any resources on how to properly order new parts, what the name of those parts are, and what websites to order from. I ran into this issue with crystals and mainsprings. TLDR, where and how do I apply this info to ordering new parts? Any help would be appreciated, I know this question is probably extremely basic, but it would mean a lot of someone would provide an answer.

[@watchrepairtutorials]

You haven't watched enough of my videos. Here you go. The Ultimate Guide for Identifying and Sourcing Watch Parts. kzbin.info/www/bejne/rJrUamCMZtipba8

[@GardenBearJake]

@@watchrepairtutorials Thank you, watching now! (pun intended)

[@johntebeau4493]

Great video! I ordered a MS for a 2824 eta and the the arbor coil was too small for my fleet of available winding arbors.Ruined it fooling about with it. After it was ruined anyhow I sort of floated a small arbor over the barrel and got it in, but risky business. Any good way to handle similar scenarios short of purchasing bergeon tools? Thanks…

[@watchrepairtutorials]

New main springs typically don’t require a main spring winder. You just pop it into the barrel. Was something different about your installation?

[@johntebeau4493]

Exactly, popped it in but later noticed bridle was poking up from the drum edge. No choice but to remove and try to rewind, and downhill we went from there. In hindsight could have tried hand winding it at that point. Oh,well……….another unexpected lesson.

[@watchrepairtutorials]

@@johntebeau4493 I’ve done some videos, showing how I install main springs out of the ring.

[@Michael_Scott_Howard]

Thank you.. well done.

[@watchrepairtutorials]

Thank you too Michael Scott.

[@Phergan]

Thanks GabeN

[@watchrepairtutorials]

You are welcome my friend

[@haping1]

Hi Alex, Thanks for this video. First thing I gonna do when servicing a watch! Great formulas as a guideline. Question: Does the amplitude (power) changes when I put a modern mainspring in an old (pocket) watch that has a carbon steel mainspring?

[@watchrepairtutorials]

Yes. I can definitely go up

[@JonTheComputerDoctor]

Great stuff thank you.

[@watchrepairtutorials]

My pleasure Jon

[@Al-po2oh]

Please tell me how to find mainsprings by size. Based on your equation, I need the following: 2.0 x .17 x 470. Thank you

[@watchrepairtutorials]

Cousins uk is the best for searching by size. Once you have the size found you can get the part # and search anywhere you want to buy from

[@itzhaccroitoru4082]

Hi Alex,I bought a Mainspring winder K&D #128,I don't know to work with it.The handle flange and winding barel is moving not proportional,Can you give me a hint?Or maybe you make a video?

[@watchrepairtutorials]

Yea, I don’t recommend them.

[@bolgerguide]

Just when I'm thinking "where the hell is Alex" he pops up.

[@watchrepairtutorials]

LOL, thanks buddy

[@pablosoto5407]

which units are used in formula/catalog for size and power? all things in mm? power is usually noted for a given vendor? Regards.

[@watchrepairtutorials]

Today it’s mm. Before it’s was both mm and the Dennison system. Sometimes.

[@boydsargeant7496]

Alex, another great video, thanks! I probably have a bunch of watches like you explained where the amplitude is low after servicing and the main spring looks good. So should I consider a thicker spring? But then what length? Often the original spring isn’t available, so should I go for a longer spring or a thicker spring! There are a lot of variables? Is there a most popular Swiss barrel ID size? In another video you spoke about the idea of buying one Bergeon winder, this might get be started? Ta!

[@watchrepairtutorials]

Well Boyd, there are lots of things that can cause low amplitude that are not mainspring related as well. If you have done everything you should have and there just no way else to getting the amplitude higher, you can try a stronger spring. Just drop the length a little.

[@boydsargeant7496]

@@watchrepairtutorials Thanks Alex!

[@boydsargeant7496]

Hi Again Alex. I thought you had a video on watch winders, but cannot find. If I had a watch winder for a 7mm diameter barrel, what barrel size up could I also use this on, 8mm, 9mm? Thinking of buying some and hoping they will work for a number of different sizes. Also the Chinese sets are per caliber but these sizes are mostly different from 7mm to 12mm so maybe this is a good starter set??? Thoughts?

[@Andy-i5g]

Brilliant

[@watchrepairtutorials]

I’m glad you think so. Thank you my friend.

[@Mr986Willis]

Hi, I bought a replacement mainspring for an Oris movement I'm working on. The spring that Cousins supplied for this caliber had dimensions that were very close to the original but the arbour was loose in the spring. I tried to tighten this up by bending the spring but broke it. I am now wondering if this is the reason my dad used to have a paraffin lamp on his bench. (Unfortunately I can't ask him as he passed away in 2019) if I anneal the first coil of the main spring can it then be tightened? Do I also need to harden & temper it again?

[@watchrepairtutorials]

I made a video about that. kzbin.info/www/bejne/sILNl5qalql2qdUsi=zy8l77v8twU0H9pu

[@dereklouis4710]

Another awesome video Alex! What do you do for mainspring diameter? I usually take the barrel ID and then pick the mainspring with a diameter one or two sizes lower. One time I bought a mainspring with a diameter JUST under the barrel ID and yet it still was too wide to press into the barrel from the containing washer. Always keen to avoid this, sometimes I order mainsprings with a diameter that is too small, and then the central loop is too small and incredibly hard to get around the arbor. Thanks!

[@watchrepairtutorials]

Thanks Derek. What are you referring to when you say diameter?

[@dereklouis4710]

@@watchrepairtutorials Like when you order a mainspring from Cousins UK, it lists 4 measurements: Height-Strength-Length-Barrel Diameter

[@watchrepairtutorials]

@@dereklouis4710 Sorry, Mainspring Diameter confused me . Its referring to the Barrel ID which is what I use to figure out what I want. I look at the overall condition of the watch. I will usually stay close to what is spec'ed out but if I have done everything I can do, then I will go a little stronger and usually shorter. I use this formula to see whats possible.

[@jarrettlaird77]

How do you deal with the inner loop of the mainspring being to large for the barrel arbor?

[@watchrepairtutorials]

Thats an upcoming video Billy

[@marki3084]

My watch fell on the floor right after the repair. Amplitude 300 degrees, now 240 degrees. now is the scrap? 

[@watchrepairtutorials]

No, but it needs service to find out what happened to it.

[@gillandro2]

Mr. Hamilton, I know ive tried to hand wind a mainspring into a watch and its a pain.... I know i could just replace a spring out right... i plan to focus on more modern watches, or size 18 pocket watches and smaller... at the moment i cant afford a full bergeon winder set... are there an average couple of winders i could purchase of the bergeon veriety that would up my watch making game without crushing my wallet? Great videos as always Sir.

[@watchrepairtutorials]

Well first, I will decide what you plan on working on. You can get a set of mainspring winders like the Mastercraft set for a couple hundred dollars. The Chinese stuff is pretty much all crab. I’ve never heard of anybody that’s happy with on sites like Esslinger you can buy handle in individual Bergeon winding barrels depending on whether you’re working on Swiss or Japanese watches which are either right hand or left hand. Sizes like 8,9 and 10 will cover a lot of movements.

[@gillandro2]

Thank you as always your info and advice is most appreciated... where can i find the master craft sets?

[@watchrepairtutorials]

@@gillandro2 well, they don’t make them anymore so you’ll need to search eBay. They come out pretty regularly. You just want to make sure that the hook on the winding harbors are good. The winding arbors on the Bergeron sets are too small for pocket watches, which I have a larger inner coil. The winding harbors on the Mastercraft sets are larger and more suited for pocket watches, which have a larger inner coil.

[@gillandro2]

@@watchrepairtutorialsi ordered the 3 sizes of burgeon winders you mentioned....but i have one ladies watch to service that will prob have a tiny barrel...how do i choose the winder for that movement as the barrel may only be like 5 mm or so? Thanks Sir

[@watchrepairtutorials]

@@gillandro2 Esslinger has a chart showing the winder sizes. Or you could just install a new spring and skip buying a winder for a one off movement

[@gillandro2]

Mr hamilton... i am getting ready to service an elgin 2004048 and was wondering about tolerances... according to the formula i need a strength of .203mm, width of 2.98 mm, and a length of 528.6mm, i looked on cas-ker for the spring and they sell two but the length of both is 546.1mm, width of 2.90mm and one is .23 mm in strength and the other is .22mm, both are for a 18s watch, and both are for a double brace and D hole spring... would these springs be ok or would i have issues with the differences in figures? Thank you as always Sir.

[@watchrepairtutorials]

There are 4 factory specked spring for 18 size full plates. they are 571 mm long, 2.92 wide and range between .209 to .229 in strength. Take you pick. Always look for the factory specs first. It was pretty close but your width was off.

[@gillandro2]

@@watchrepairtutorials i did the length with a tape and it actually measured exactly the 21.5" or 549.1mm they sell which i wasnt expecting thank you

[@rammsteinsiegfried6750]

Nice watch on youre wrist.Wich one is ?

[@watchrepairtutorials]

One I built with a PT 5000 . Kind of a flieger style.

[@rammsteinsiegfried6750]

Thanks.Very nice.Almost like my Sinn836.

[@seangerst6561]

There are so many things comming to live that i never thought about...👍🏼👍🏼👍🏼 PS. Do you know how they made a temperatur compensaded ballence wheel. I mean how did they bind the steel to the brass?

[@watchrepairtutorials]

The balance spring was made of an outer layer of steel and an inner layer of an alloy called Invar, which had a very low coefficient of thermal expansion. As the temperature changed, the two layers expanded or contracted in opposite directions, again canceling out the effect on the balance wheel's oscillation rate.

[@seangerst6561]

@@watchrepairtutorials but wouldn't the layers of the ballence wheel seperate over time? I mean If it is geting hot and cold for over 100 years.😅👍🏼👍🏼

[@watchrepairtutorials]

@@seangerst6561 most watches are not exposed to extreme changes

[@nunyabusiness9056]

Hey, resident of the discord iirc you helped set up here. Does this rule apply the same to japanese watches? I"m trying to source a new mainspring and alarm mainspring for a seiko 4006 bell matic movement. When look up peoples struggles in other forums to use generic mainsprings what i CONSTANTLY see is people complaining of the inner coil being too small to fit around the arbor causing it to break, including specifically in the 4006 movement. Is this not an issue that we have to worry about because it seems to be messing some people up. I can find replacement mainsprings for the thing on ebay but i'm not too keen on paying 40 dollars in shipping from israel and the phillipines for a thing the size of a postage stamp lol.

[@watchrepairtutorials]

As far as the mainspring is concerned yes. The math would be the same. As for as the alarm spring is concerned I am not sure if it follows the same calculation or not because it has a different requirement. I would certainly try it. The inner coil is often a problem when sourcing mainsprings in vintage movements. That’s why I made this video. How to Make the Inner Coil of a Mainspring Smaller- Without Breaking It kzbin.info/www/bejne/sILNl5qalql2qdU The same principle can be used to make the inner coil larger.

[@nunyabusiness9056]

@@watchrepairtutorials Hey, i watched it and it was a great help in fixing the coil of my alarm mainspring which frankly probably needs to be replaced anyways. You mentioned the rule of finding the length of american mainsprings and swiss ones, but is there a rule on japanese ones? I"m trying to buy a handful of seiko mainsprings. Appreciate all ya do man.

[@watchrepairtutorials]

@@nunyabusiness9056 I would follow the Swiss formula, but again I’m not sure if it would apply to the spring for the alarm

[@nunyabusiness9056]

@@watchrepairtutorials Well i guess i'll find out cuz i ordered one but aired a little on the shorter side just in case. That said in case anybody reads this or anybody else asks you, i did the swiss formula for the actual mainspring of the 4006 and it brought me on the cousins mainspring search by height feature to one almost exactly that is actually listed specifically as the correct generic replacement for the 4006. So i think you are correct that the japanese might be using the swiss formula more. That said since all it does is power an alarm, i got a feeling there's a bit more wiggle room with the alarm spring.

[@oraszuletik]

Rozé equation?

[@watchrepairtutorials]

Ce n’est pas traduire

[@a.aguilar]

Alex, so far I've always reused the mainspring that came with the watches I've serviced, for a number of reasons. In the last watch I worked on I tried to replace it, but failed for something that nobody could give me a tip to solve: the size of the coil in the new mainspring for the arbor was too big so the arbor wouldn't hook the spring, even the MS winder arbor was thinner than that coil. I tried to close this coil a bit but of course I broke it. This coil size is not specified in the spring parameters, so how can I choose a MS that will also fit my arbor size?

[@watchrepairtutorials]

Inner coil size is not called out for in the specs. There is no easy answer to that unless you can get an OEM spring. Maybe I will make a video about adjusting the inner coil

[@larslindegren5632]

So all you can do if you don´t find the exact right mainspring is to pick the one closest you can find and that is the best you can do?!?

[@watchrepairtutorials]

Yes, other than making your own mainspring

[@donaldkerns8234]

Measuring a 1970 Westclox Scottie mainspring barrel, it yields an inner diameter (ID) of 17.6mm. Running it through the formulas provides a strength of 0.205mm and a length of 528mm. The barrel depth comes in at 3.66mm. The Westclox doesn't have a barrel top, so I'd call it 3.5mm. 3.5 x 0.205 x 528 Does that seem reasonable? Please don't laugh at putting the effort into a Westclox, it is cheap practice before moving onto something more "real."

[@watchrepairtutorials]

Why would I laugh. Sure, I would try it depending on what’s available