A serious (as in not troll) requestfor help w/ultrasonic transducer

[watchmaker]

Many of us use a 50 year old ultrasonic cleaning machine manufactured by L&R in New Jersey.  It is STILL accepted by Rolex and everyone else.

The issue is that the transducer element fails over time.  Sometimes it is an epoxy fail, but often the "rock" is damaged and cannot be reused.

Below is a picture.  We refer to it as a "donut" because the can it sits in has a channel w/ thru hole for the absket motor shaft to pass through (the basket rotated beneath the assembled transducer).

The Dimensions are:

Height  28mm
OD  65 mm
ID 21 mm

Any thoughts on sources, replacements ar alternatives would be greatly appreciated.  These were set to 87 kHz.

Thanks,

Dewey

[coppercone2]

if your doing this for money then replacing it is kind of like messing with a tuned cavity, you can't be sure of if there is no areas of stronger force if you change the transducer and its damping effect on the system.

i doubt you will get a certifiable replacement easily


a practical test would be to put foil in there and see how it does when you compare two different transducers. if the rolex one damages the foil in the same spots as the replacement in the same time, you are probobly good. must be done with same chemicals at same temp (stir it well before test)

I suspect it might be bull shit unless you take way too long and use bad chemicals, because a bond wire in a IC is finer then anything that can ever be in a mechanical watch. For most IC you don't see even a small failure % on sensitive parts up to the 6 minute mark.


I assume what you are worried about is dodgy plating coming off.


The frequency is more trouble on large structures, maybe. But the only thing I can think of in a watch that is sensitive is the long spiral spring. But that is usually replaced instead of cleaned anyway right?

the other sensitive part is the face with the inks and stuff, but that is probobly a question of not leaving it in there for too long and using mild chemicals.


to measure the frequency connect a oscilloscope to the power system (just make sure its voltage is not too high for scope)


getting a very thin foil in there will show damage quickly on it to use as a test particle I think. You can do alot thinner then aluminum foil to try to see a effect quicker.  That you can position on a articulating arm (dial indicator arm) with a aligator clip on it

[IanB]

I can't help feeling that 50 years old is ancient, and whatever parts it contained would be long out of production unless you can find new-old-stock somewhere. Your best resource would be the watch repair community rather than an electronics forum.

A quick google for ultrasonic cleaners shows that new ultrasonic cleaners for watch parts are readily available, either in the USA (expensive?) or from China (less expensive?). It might be easier to buy a new machine than to try repairing an old machine?

When I watch YouTube videos on watch repair, it doesn't seem there is anything too complicated about them. You put the parts in the baskets, put the baskets in the machine, and let it run until the cycle is over. The cleaning solution is going to be the same with new or old, and I'm not really sure how metal parts can be damaged?

(The only thing that boggles my mind is how someone can completely disassemble a watch, clean the parts, and put it all back together again with all those minute screws, jewels and other parts that have to go back in exactly the right order. I find it hard enough just replacing a watch battery.)

[watchmaker]

Thanks.  I know about the foil test.

The problem faced by watchmakers is that this machine is accepted by all brands.  TO replace it with a new unit that is accepted cost from $8K up to over $12K.

I am not repairing these, there is a business that does only these.  While I am hoping my unit is down because of a failed capacitor array (to be checked this week), the next failure point is the head.  And the tech and his Dad have been trying to come up with replacements for broken transducers since they ran out of their stock of replacements.

I am asking here because I want these units to continue to be available rather than force more watchmakers out of business or have to line the pockets of the brands who have a vested interest in the new machines.

I do not need the machine for accounts since I am retired, and I do have a work around for getting my parts chemically clean (ultrasonic tank bath then the 4 jar machine).  Cumbersome, but it will work.  Those in business cannot afford the lost time.

If anyone know a source, it may make business sense for the repair business to have 50 or 100 donuts made.

[coppercone2]

rolex is like bently they have a procedure and approved tool for everything you can't service customers if you go out on your own without at least very hard evidence

you will be dealing with a 800$ an hour lawyer as your customer

[coppercone2]

For the foil, I mean hang some test strips in the tank of the good one, see how the pattern looks, and use that to determine if a new cleaner is similar enough to act as a replacement.

i think the part you are looking for is a piezo disk. there is piezo disk manufacturers (i.e. piezo.com). It is a special type of ceramic machined into a shape for the transducer.


https://piezo.com/pages/build-custom-piezo

too thin

https://www.ceramtec-industrial.com/en/piezo-designs/rings


I think its extremely hard to do, and even harder to verify. unless you got manufacturers specs....


the only thing I can think of is that cheap ass cleaners might have 'hot spots' of increased ultrasonic activity that can damage parts. otherwise the ultrasonic power /tank size factor should be more then enough to make a sensible decision for replacement

[watchmaker]

if your doing this for money then replacing it is kind of like messing with a tuned cavity, you can't be sure of if there is no areas of stronger force if you change the transducer and its damping effect on the system.

i doubt you will get a certifiable replacement easily


a practical test would be to put foil in there and see how it does when you compare two different transducers. if the rolex one damages the foil in the same spots as the replacement in the same time, you are probobly good. must be done with same chemicals at same temp (stir it well before test)

I suspect it might be bull shit unless you take way too long and use bad chemicals, because a bond wire in a IC is finer then anything that can ever be in a mechanical watch. For most IC you don't see even a small failure % on sensitive parts up to the 6 minute mark.


I assume what you are worried about is dodgy plating coming off.


The frequency is more trouble on large structures, maybe. But the only thing I can think of in a watch that is sensitive is the long spiral spring. But that is usually replaced instead of cleaned anyway right?

the other sensitive part is the face with the inks and stuff, but that is probobly a question of not leaving it in there for too long and using mild chemicals.


to measure the frequency connect a oscilloscope to the power system (just make sure its voltage is not too high for scope)


getting a very thin foil in there will show damage quickly on it to use as a test particle I think. You can do alot thinner then aluminum foil to try to see a effect quicker.  That you can position on a articulating arm (dial indicator arm) with a aligator clip on it

See the reply that I was typing while you posted. 

The issue is chemical cleanliness.  Then comes the issue that for those with parts accounts, the cleaning machine has to be accepted by the brands.  This 50 year old machine is one of the few that are accepted.

Refurbished, this machine costs close to $5K USD. The new machines (Greiner, Matador) start at $7K USD.  This is not a problem for me since I no longer have a parts account.  But many of my colleagues do, and most have this machine.

You should see the cost for a water leak tester!

[coppercone2]

lol what the hell can they do other then swap the tank out? does it have some other plumbing?


Its stainless steel. but regardless you can replicate a bowl from any sheet metal producer out of whatever alloy you want. that sounds like marketing BS. The stainless steel 'leaching' between grades is probobly fractions of a mm/year (corrosion rate). It might matter if you leave the liquid in the tank and its seriously dodgy shit. But if you drain the liquid into a glass bottle, rinse it before use... keep the tank polished... IMO its ludicrus

and you could just get a over powered tank by 15% and put the stuff you are cleaning in a glass jar. then it will be cleaner then any manufacturers metal tank

i.e. don't use a nickel plated tank (harbor freight).

if it really mattered if its clean, you would use a glass basin with a ultrasonic wand. clearly metal is good enough for a mechanical mechanism.....

[IanB]

I am not repairing these, there is a business that does only these.  While I am hoping my unit is down because of a failed capacitor array (to be checked this week), the next failure point is the head.  And the tech and his Dad have been trying to come up with replacements for broken transducers since they ran out of their stock of replacements.

I am asking here because I want these units to continue to be available rather than force more watchmakers out of business or have to line the pockets of the brands who have a vested interest in the new machines.

If anyone know a source, it may make business sense for the repair business to have 50 or 100 donuts made.

Unfortunately, I can't tell what this "donut" thing is? If I search for "ultrasonic transducers" I find pictures of things that look like the one below. They are shiny metal in appearance and have two electrical terminals for the power to be applied. They don't look like your picture.

If you were able to show more pictures of the whole machine and the assembly of the transducer and associated parts, it might be easier for someone to search for equivalents. But unless you find here an expert in the field, it is only guesswork.

https://www.amazon.com/Conversion-Efficiency-Ultrasonic-Piezoelectric-Transducer/dp/B0CLTX5JMD

[watchmaker]

rolex is like bently they have a procedure and approved tool for everything you can't service customers if you go out on your own without at least very hard evidence

you will be dealing with a 800$ an hour lawyer as your customer

And if your business is servicing Bentley, you need to be Bentley approved.

The standards are the same for all brands, Swatch (Omega and Breguet), Richemont (LeCoultre), Rolex, Patek, Audemars.

Many of the standards are sensible, some are intended to make the cost of entry intentionally high.  These 50 year old Tempos are the difference between staying in business or being forced out for many of my colleagues.

If you want a parts account (which means the ability to buy parts), then you need to meet that standards.

[coppercone2]

i wanna see what they say about contamination when you put it in a glass jar and prove there is ultrasonic energy in there. its how you do chemistry. they have wands for starting reactions in glassware. reactions that require the purest of pure conditions, for biological science.

[IanB]

Then comes the issue that for those with parts accounts, the cleaning machine has to be accepted by the brands.  This 50 year old machine is one of the few that are accepted.

Refurbished, this machine costs close to $5K USD. The new machines (Greiner, Matador) start at $7K USD.  This is not a problem for me since I no longer have a parts account.  But many of my colleagues do, and most have this machine.

You should see the cost for a water leak tester!

Honestly, this is ludicrous! An ultrasonic cleaner suitable for watch parts and jewelry shouldn't cost more than a few hundred dollars.

As for being accepted by the brands, I have heard enough horror stories of watches being damaged by authorized repairers that I would be very wary of trusting an expensive timepiece to one of them. It's not the parts cleaner that does the damage, it is the incompetent human doing the work.

I would rather put my trust in a known independent watch repairer with a track record and good references. (Though, granted, finding one of those might not be easy.)

[watchmaker]

I am not repairing these, there is a business that does only these.  While I am hoping my unit is down because of a failed capacitor array (to be checked this week), the next failure point is the head.  And the tech and his Dad have been trying to come up with replacements for broken transducers since they ran out of their stock of replacements.

I am asking here because I want these units to continue to be available rather than force more watchmakers out of business or have to line the pockets of the brands who have a vested interest in the new machines.

If anyone know a source, it may make business sense for the repair business to have 50 or 100 donuts made.

Thanks, I will upload a pic tomorrow,  But there is no real real mass-produced transducer replacement.  The motor arbor must pass thru the assembled transducer to the partsbasket which is below the transducer.

Here is a link to a YT on showing the machine:




Unfortunately, I can't tell what this "donut" thing is? If I search for "ultrasonic transducers" I find pictures of things that look like the one below. They are shiny metal in appearance and have two electrical terminals for the power to be applied. They don't look like your picture.

If you were able to show more pictures of the whole machine and the assembly of the transducer and associated parts, it might be easier for someone to search for equivalents. But unless you find here an expert in the field, it is only guesswork.

https://www.amazon.com/Conversion-Efficiency-Ultrasonic-Piezoelectric-Transducer/dp/B0CLTX5JMD

[watchmaker]

Then comes the issue that for those with parts accounts, the cleaning machine has to be accepted by the brands.  This 50 year old machine is one of the few that are accepted.

Refurbished, this machine costs close to $5K USD. The new machines (Greiner, Matador) start at $7K USD.  This is not a problem for me since I no longer have a parts account.  But many of my colleagues do, and most have this machine.

You should see the cost for a water leak tester!

Honestly, this is ludicrous! An ultrasonic cleaner suitable for watch parts and jewelry shouldn't cost more than a few hundred dollars.

As for being accepted by the brands, I have heard enough horror stories of watches being damaged by authorized repairers that I would be very wary of trusting an expensive timepiece to one of them. It's not the parts cleaner that does the damage, it is the incompetent human doing the work.

I would rather put my trust in a known independent watch repairer with a track record and good references. (Though, granted, finding one of those might not be easy.)

All the rants have been made for over 2 decades as parts account were closed.  But now comes the time to deal with the reality.

If you want to know the real joke, ALL of the major brands are partners in Bergeon, one of the major distributors of these kinds of machines  Portescop (Greiner) is a part of the Swiss Watchmaking consortium (cartel).  Cartel is not a dirty word to the Swiss and the govt, banks and manufacturing have openly operated as a cartel since WWI.  Collaboration is better than competition in their view.  FOr example, many brands buy the ETA 7750 to use in their watches.

I gave up my parts accounts when it became a requirement to buy a water tester for $11K (yes that $11K).  Omega allowed me to keep a small account and to continue as a service provider, but I only serviced vintage Omegas even tohugh I was trained on the Coaxial and the chronograph module.

The ultimate goal is to bring ALL service back into the brand house.  Audemars no longer even services anything in the US, it all goes back to Switz.
Last I heard, ROlex was sending its USA work to South America an  China.  I am pretty sure Omega is still done in the US Swatch service centers, but I am not sure about the higher-end Swatchnames.  They probably go back home.

I was involved in the effort to get the US watchmaker groups to provide evidence to the FTC case about parts restrictions back in the late 1990s.  But the volunteer officers and board members preferred to think they would be protected from closures if the kept their mouths shut (I still have the correspondence).  Happplily, they were not even close to the last of accounts to be closed .  Camus.  (They actually thought they were as smart s a Rolex International VP!!)

So I am not excersized about the situation.  But the trade treated me very well, and I have always tried to further its interests.

[coppercone2]

what the hell do they care about the water for?

you rinse it with DI water.


You know a standard ass lab can make semiconductor clean surfaces. as EE we know this. Usually it involves a DDI water rinse at the end to get rid of any 'chemicals'.

For steel you can find all sorts of free access tables for which one is the least contamination. its basic science 101 for some fields, even at an associates level (technician) to have to know how to clean stuff. the only requirementi s money, because it costs a bit more for the spectroscopic grade stuff. the most basic ass job in analytical chemistry at 15.50 an hour high school intern requires knowledge of this.

that's right. spectro scopic grade. for things like precision diffraction gratings with micron features.


what in a watch requires this nonsense? The only part where its not cringe worthy is prep before plating. then its important to be really clean, for the highest quality. But its little more then careful rinsing wiht clean stuff. Optics seems harder to clean because of scratching, and fragile thin films... but its only a problem if you basically don't spend any time researching and don't spend any more (as I found out with some laser stuff, because its basically plastic coated and there is some incompatibilities that seem like nonsense to any home owner that has glass (late roman empire ) (no ammonia))


I only ever seen the ultrasonic do bad things with brass, when loaded with concenrated acid. then it starts plating the tub if you leave it for 30 min lol



and if it really mattered, that fancy machine would use a glass transducer for ultrasonic delivery. they would figure out how if they are worried about ion contamination .  So you have a glass bowl but you stick metal in it. you would either use a much bigger tank to deliver the energy through water surrounding a glass bowl, or figure out how to deliver it through a glass horn that is dipped in (i.e. maybe quartz is tough enough). because money is no object for the swiss and they would want the best performance. the term you want for that apparatus your fixing is ultrasonic horn that is glued to the tank. Basically if you are after the ultimate clean, putting a mason jar in there with a loose lid on it filled with the cleanest water is going to be cleaner then that expensive machine in the video, because their dipping metal into it. it might matter, if its preparing a sample for a ICP plasma metal study.  . I would put money on that, that my 5$ beaker filled with clean water, with a watch glass on top in a chinese ultrasonic cleaner would be cleaner then a water sample from that machine for metal ions, in what... the PPB concentration?



talk about stepping on the little guy. because the big guy can't innovate, or rather does not want to... and instead wants a 'subscription' fee from maintence contact. all these companies now think their so smart an hot for trying to make you subscribe.

usually it means your R&D is a dumpster fire that can't make anything people actually want and its sad because there is so much analog computing watches can do. they did the turbulon. maybe they should come up with something new so they don't have to worry about their ancient designs. three dimensional mechanical displays,things with prisms, new materials,... nope...


I noticed this with victornox too. the swiss army knife guys. leatherman has them in the DUST because they innovated. actually managed to use magnets and their not stupid and annoying. and other people can't get the super alloys right so the off brand tools are OK if you don't mind your knife snapping on you because it felt like it.

[floobydust]

L&R Ultrasonics Tempo 400 PC board pic and schematic, apparently 100 84kHz: https://www.eevblog.com/forum/repair/matching-ultrasonic-transducer/
I think because it has no tank, just a small jar and the higher frequency, it might do better with fine items. It's only got one electrolytic capacitor, one output cap to replace.

OP, your donut in the pic is damaged, busted, dead. Not an expert or pics/size of other parts but it looks like an Langevin transducer maybe like these pics. Many companies make them and the parts.
You could try to figure out the original manufacturer with some detective work. Or just source another donut i.e. rings and many many more manufacturers of the parts. It's not all unicorn magic.
L&R does have some kind of dosimeter that could be used to compare old/new.

[watchmaker]

OP, your donut in the pic is damaged, busted, dead. Not an expert or pics/size of other parts but it looks like an Langevin transducer maybe like these pics. Many companies make them and the parts.
You could try to figure out the original manufacturer with some detective work. Or just source another donut i.e. rings and many many more manufacturers of the parts. It's not all unicorn magic.
L&R does have some kind of dosimeter that could be used to compare old/new.

Floobydust,

No shit   Thank you for helping me figure out what to call the thing!  I figured someone here would know how I should start sourcing it.

The point is that these machines are failing because of transducer (Donut) failure.  And to avoid buying an $8K machine to stay in business, my colleagues would benefit from the ability to have the "donut" replaced.  Not by me, but by the last buggy whip maker.

I destroyed the one in the picture you see.  It was one that no longer functioned and I wanted to see what was need so I could use the expertise here to possibly source a manufacturer who could make 50 to 100 pieces.


All,

Not interested about "what should be".  The situation is what it is and started 30 years ago when the brands began this process.  It was the first major case to override the Xerox doctrine and reestablished parts restrictions to independent service organizations.

The horses are out of the barn, it has all been litigated and judged.  So if anyone else can help with potential manufacturers of the element, a referral would be useful.

Thanks and regards,

Dewey

[floobydust]

I thought maybe a gorilla over-tightened it and crunched it, it's broken in so many places 

I haven't see any pics of the transducer assembly. It's got a horn or an arm or a booster?
You need dimensions of the arm, you already have them for the donut, not sure if all aluminum - then go to any manufacturer and ask for engineering help or maybe hit up someone like this https://blog.piezo.com/horn-transmission-and-its-applications
Engineering details here: https://www.ultrasonic-resonators.org/design/transducers/transducer_design.html
They show only a few different piezo materials used. I hope yours does not use beryllium electrodes.
You could order up the same size part and simply try it out too.

[IanB]

what in a watch requires this nonsense? The only part where its not cringe worthy is prep before plating. then its important to be really clean, for the highest quality. But its little more then careful rinsing wiht clean stuff. Optics seems harder to clean because of scratching, and fragile thin films... but its only a problem if you basically don't spend any time researching and don't spend any more (as I found out with some laser stuff, because its basically plastic coated and there is some incompatibilities that seem like nonsense to any home owner that has glass (late roman empire ) (no ammonia))

The main issue is to remove old, dried on lubricant, and various particles of dust and grit that might be hidden away in crevices and pivot holes where they can cause major problems.

It's only the mechanical parts that go into a cleaning machine. Decorative parts need careful and separate treatment to avoid ruining them.

Here is a video that shows what the whole process is about, using a non-ultrasonic machine:

[IanB]

For anyone who wants an ASMR video to relax to, here is a complete tear down and reassembly of a watch. I can only dream of being able to do something like this. I have struggled so much even getting little tiny screws back into their holes.

[coppercone2]

what in a watch requires this nonsense? The only part where its not cringe worthy is prep before plating. then its important to be really clean, for the highest quality. But its little more then careful rinsing wiht clean stuff. Optics seems harder to clean because of scratching, and fragile thin films... but its only a problem if you basically don't spend any time researching and don't spend any more (as I found out with some laser stuff, because its basically plastic coated and there is some incompatibilities that seem like nonsense to any home owner that has glass (late roman empire ) (no ammonia))

The main issue is to remove old, dried on lubricant, and various particles of dust and grit that might be hidden away in crevices and pivot holes where they can cause major problems.

It's only the mechanical parts that go into a cleaning machine. Decorative parts need careful and separate treatment to avoid ruining them.

Here is a video that shows what the whole process is about, using a non-ultrasonic machine:

yeah but the purity requirement seems to be for ICP machine calibration standards. I mean they should just do something reasonable like demand you dress like the swiss guard while working on the watch in their 5000$ dress uniform

[ebastler]

I don't have a specific product lead, but a recommendation for a company to contact: Sensor Technologies in Canada, a family-owned manufacturer of piezo ceramics and transducers. They were most helpful when I built a homebrew scanning tunneling microscope. (A long time ago, but the company is still run by the same family.)

Making a piezo element with a custom size is entirely possible, but would only make commercial sense if you need quite a few, I assume. But maybe they have leftover stock in a suitable size. The call the "donut" geometry a "washer" (or ring).

https://sensortechcanada.com/piezoelectric-ceramics/

[watchmaker]

Thank you Floobydust and Eblaster.  Sadly, I do think it is Beryllium (tech said barium and likely meant Beryllium).  But at least we can start.

The transducer is simply the Al can and the donut. 

BTW, the schematic in the linked post above is for a different 400 variant.  The last one had a more reliable generator board that fit but required a capacitor array.  The "new" boards fail rarely (as in has not been seen) but the array does.  This is what we are hoping is down on my machine.

L&R ceased production of these about 20 years ago.  One shop purchased all the parts inventory.  That transducer supply has been exhausted and he forgot to get the vendor records.  So it goes.

Regards,

Dewey

[watchmaker]

For anyone who wants an ASMR video to relax to, here is a complete tear down and reassembly of a watch. I can only dream of being able to do something like this. I have struggled so much even getting little tiny screws back into their holes.

You do realize of course this is like me telling Tautech how to use a scope.  Or relying on YT to explain earthing and isolation transformers.

Then all parts but the mainspring are put into the machine.  EVERYTHING is disassembled.  You cannot get things like capped jewels clean wi/o disassembly.  Then parts are handled with finger cots and I use only bronze tweezers.  Oils pots are changed at least weekly.  Cleaning solutions at least twice a week.  "Stains" are removed with lab grade heptane.  Surgical sponge swabs are used to remove dust and only a vacuum is on the bench, no compressed air.

All work is done under at least 15X, inspection of parts and oiling at 60X.

This is in MY shop.  In parts accounts shops you now need a clean room atmosphere.  Plus ventilation to remove the fumes from the cleaning machines which are to be in a separate room that can be closed off.

While the uninitiated may think this is silly, it reduces the risk of contamination of the lubricants.  And while many bemoan the cost of the lubricants and the cleaning requirements, there are two reasons for this.  One is to ensure compatibility of the lubricants should they come into contact with each other.  We even now use teflon coated mainsprings so we only lubricate the MS arbor and in automatics the MS barrel wall.

The other reason is the standards are not written for independents, let alone amateurs.  They ensure longer life of cleaning solutions in the service centers that have to comply with very strict disposal laws,  So they do no want incompatible lubricants contaminating their solutions.

FWIW, adhering to these standards, my comeback rate on watches was around 2 percent.  Which is considered way too low for profit.  Should be closer to 10%.  But since most of my work was and is period correct clocks for warbird and vintage aircraft, I need to avoid the inconvenience of pulling the piece from the instrument panel because of my error.  Years ago I tried doing work based on price and found that either I could do correct work or cheap work, but I could only do one or the other.  I chose the former which is how you get customers who are physicists and engineers (from Los Alamos and JPL), astronomers from the US Naval Observatory, command pilots and blue water navigators.  People who understand precision instruments and the skills required to maintain them.

So yes, there are those who are naive and think they know better than a fully trained watchmaker who charges twice as much. 

But then, there are those who think they should work on high energy circuits using a $30 multimeter.

The former can live to spread their stories.  The latter seem to be self-limited by circumstance.

Here are pics of my shop as I left it last nite.  Bear in mind I "distracted" by my new hobby (EE) so it is not as organized as I like to keep it.

Oh, forgot.  After the watch is reassembled it's correct function is verified on using performance analysis instruments (beat error, amplitude and rate in all positions), run for 7 days and also visually and functionally by one of us that did not do the work.  If any parameter falls short, the watch is inspected and on the bench until the fault is found, visually verified and corrected.  Then the QA process starts again from the beginning..  In short, strict quality control. 

As was said by one of the most famous teachers  "It is one thing to make a watch tick, it is quite another to ensure it functions as originally intended". (which means as a precision instrument).

[IanB]

For anyone who wants an ASMR video to relax to, here is a complete tear down and reassembly of a watch. I can only dream of being able to do something like this. I have struggled so much even getting little tiny screws back into their holes.

You do realize of course this is like me telling Tautech how to use a scope.  Or relying on YT to explain earthing and isolation transformers.

Yes, of course. It was just, as I said, for relaxation. There is something captivating about watching such work being performed.