Jump to content
When you buy through links on our site, we may earn an affiliate commission.
  • Current Donation Goals

Movement poll and review - New 37mm Asian7750/a07.211


gran

Do you want 25 Jewelled Bearings in your a7750?  

18 members have voted

  1. 1. Do you expect to get Jewelledbearings in your A7750 movements?

    • Yes! Jewelled bearings looks much better and closer to genuine
    • Yes! jewelled bearings are a sign of quality
    • No! As long as there is metal bearings there
      0
    • No! Jewelled bearings are just hype
      0
  2. 2. Would you buy a replica if you knew that Metal bearings were used instead of jewelled bearings for most gears?

    • Metal bearings are acceptable
    • NO! I want Jewelled Bearings on the moving parts
    • I do not care
      0
    • Yes! I prefer metal bearings
      0


Recommended Posts

Be aware that some of the new asian 7750 movements around do not have 25 jewels in them!!!

(Jewel = jewel-lined pivot hole with ruby red colour)

The New 37mm Asian7750/a07.211 is larger in diametre than the asian7750 and Swiss7750 movement,

and is same size as the new ETA Valgranges.

These larger 37mm New Asian 7750 (=a07.211) movements fit well in larger watches,

like the CHOPARD GTXXL Chronograph

However the new 7750 around appear to have very few jewels in them,

but have more than 15 metal bearings instead (This has also been confirmed by The Zigmeister)

Jewels = A jewel bearing is a bearing in which a metal spindle turns in a jewel-lined pivot hole with ruby red colour. Jewel bearings were invented in 1704 for use in watches by Nicolas Fatio de Duillier, Peter Debaufre, and Jacob Debaufre, who received an English patent for the idea. Originally natural jewels were used, such as sapphire, ruby, and garnet. In 1902, a process to make synthetic sapphire and ruby (crystalline aluminum oxide, also known as corundum) was invented by Auguste Verneuil, making jewelled bearings much less expensive. Today most jewelled bearings are synthetic ruby or sapphire http://en.wikipedia.org/wiki/Jewel_bearing

I bought a CHOPARD GTXXL Chrono with this new larger asian 7750 movement (=asian a07.211 movement)

I spotted that the red ruby colour was absent ontop of 3 gears

I sent it to Domi for service, as I could see it was lacking 3 of the the usual ruby red Jewelled bearings that are typical for 7750 movements :(

It turned out this movement has metal bearings :o in fact it had only few ruby red jewels were used

Note that jeweled bearings are most common in a modern movement

I was not at all happy with this and had the movement changed (I will post more on the change of movements in a diffrent thread later).

So is the new asian 7750 (= a07.211) a bad movement? The Zigmeister said that, and I quote;

"When you design and build a movement with metal jewels not sapphire ones, then expect to see metal jewels. This is how this particular A7750 has been build and designed. If there were no jewels, then you could blame QC, but not in this instance, QC is working just fine, all the jewels are in place and doing what they are designed to do..Many vintage pocket watch "jewels" are nothing more than holes in the brass plates, clocks are the same, the pivots turn in the brass plates."

However the dealers do not properly describe this new asian 7750,

and certainly do not advertise that metal bearings have been used

I find this not to be acceptable

when not explicitly explained to the buyers,

as this new 7750 is likely less expensive to produce,

and less beautiful to look at,

and further from the genuine in appearance

Dealers to be trusted on this?

A pictorial description of the asian a07.211 (= New A7750) movement below:

First a comparison of the new 7750 (= a07.211) and SWISS 7750 and normal asian A7750

comparisonk.jpg

A partial breakdown of the new Asian A7750 (= Asian a07.211)

trashfromjoshua.jpg

As a finishing note, I hope and pray The Zigmeister or any other of our excellent watchmakers do a more detailed review on this topic so all (RWG menbers and Dealers alike) can be well educated about this and other asian 7750s around so members do not end up getting a big surprise

+ I will post more on this topic later

Thank you

Gran :thumbsupsmileyanim:

Link to comment
Share on other sites

But ziggy also said that this type of jewel has worked for many years without problems, How ever i count at least 7 ruby jewels

4 in the top and bottom shock protection

1 roller jewel

2 escape jewels

I will be very surprised if these 7 are not there

However that said, in my eyes this is not what is advertised, the amount of jewels to me is the amount of rubys not the amount of bearings.

Link to comment
Share on other sites

Bur The Zigmeister also said that this type of jewel has worked for many years without problems, How ever i count at least 7 ruby jewels

4 in the top and bottom shock protection

1 roller jewel

2 escape jewels

I will be very surprised if these 7 are not there

Ok good points you make, have edited that part as the numbesr may vary and yes The Zigmeisters comments are clearly stated in my post and anser to your question is Yes!

Question is still do you want true jewels or metal bearings in your movement :)

Link to comment
Share on other sites

I am probably a bit less concerned about the technology (or lack of) in the rep movement, and more concerned with 'truth in advertising'.

It would be nice to know the watches are in fact A7750 clones or A07.211. And on that note: if a GEN ETA Valgranges can be a direct R&R swap.

Link to comment
Share on other sites

Very good post. I checked and indeed I also have models with metal instead of jewels. Easy to see if you see one with jewels and metal next to each other (have both). These movements must be much cheaper to produce and I think are less in quality. This is a post that might be quit important. I also would like the Dealers to be honest when they advertise their watches.The question is why they do use metal instead of rubies. As far as I know the rubies they use nowadays are synthetic and very cheap to produce.

Edited by Timemaster
Link to comment
Share on other sites

Thanks all Timemaster,cornerstone, Ronin, maxman, deniz21 and FxrAndy :thumbsupsmileyanim:

And yes! It is indeed a shame that the dealers do not give us the facts about the movements.

And yes! Its is also a conondrum why metal and not jewels is used in these bearings

trustequation-718721.jpg

Link to comment
Share on other sites

The only difference between sapphire and ruby is that different impurities have been added to change the color; there is no difference in their properties as a bearing. advantage of using jewels is that their ultrahard slick surface has a lower coefficient of friction with metal. The static coefficient of friction of steel-on-steel is 0.58, while that of sapphire-on-steel is 0.10-0.15.

Why they are used ?

Jewels serve two purposes in a watch.[9] First, reduced friction can increase accuracy. Friction in the wheel train bearings and the escapement causes slight variations in the impulses applied to the balance wheel, causing variations in the rate of timekeeping. The low, predictable friction of jewel surfaces reduces these variations. Second, they can increase the life of the bearings. In unjeweled bearings, the pivots of the watch's wheels rotate in holes in the plates supporting the movement. The sideways force applied by the driving gear causes more pressure and friction on one side of the hole. In some of the wheels, the rotating shaft can eventually wear away the hole until it is oval shaped, and the watch stops.

The above is taken form wikipedia.

Of course not all gears need a jewel. If a gear is used to move the hour hand it will not have that much friction as it moves really slow. So I think the Chinese thought why use a jewel as it is not really necessary.

I worked in the computer industry and once was told by a main board engineer that the first design was one of the best. Later designs were stripped en they took as much as possible part of the beards because each of the removed coils, resistors or conductors could bring extra profits as hundred thousands of boards where produced. Some revisions were faulty or unstable because they took of too much components. He also told me that the economical lifespan of a main board was 3 years (back in 2000) so they did not bother if the quality was so poor that a board would start to be unstable after a few years. They bought the most cheap components to make more profit. The "leaking conductor incident" was an example of this cost cutting method that however cost a lot of money for the manufacturers as many went defective earlier then intended.

The metal bearings are probably done because it saves productions costs and are not really necessary. The intended lifespan of the movements might be for a few years only. A Swiss however can work for generations when serviced.

The Asian 28800bph with 25 jewels can also be serviced and have a long lifespan. The Chinese now make a mistake in my opinion. Yes you can save a few dollar extra when you make the movement cheaper, or use a lower quality material for the lume or AR coating. The lume and AR can be changed later but a movement improvement is something else. I also do not understand that the factories use a poor quality lume. Customers would rather pay some extra for quality and by trying to produce the watches as cheap as possible and trying to sell them for the highest possible price they make the wrong choice and make now a few bucks extra but in the end will hurt their profits as customers will turn their back on them. I buy reps because they do not only look quit similar as the gen but also because they started to use reasonable quality of parts. An Asian 2824 can be just as reliable as a Swiss and you can have an almost similar looking watch with a movement that looks and works like the one in a gen. The decision to use less quality parts is what i think not what customers want and will only widen the gap between Chinese watch industry and Swiss again.

Edited by Timemaster
Link to comment
Share on other sites

The Chinese now make a mistake in my opinion. Yes you can save a few dollar extra when you make the movement cheaper, or use a lower quality material for the lume or AR coating. The lume and AR can be changed later but a movement improvement is something else. I also do not understand that the factories use a poor quality lume. Customers would rather pay some extra for quality and by trying to produce the watches as cheap as possible and trying to sell them for the highest possible price they make the wrong choice and make now a few bucks extra but in the end will hurt their profits as customers will turn their back on them. I buy reps because they do not only look quit similar as the gen but also because they started to use reasonable quality of parts. An Asian 2824 can be just as reliable as a Swiss and you can have an almost similar looking watch with a movement that looks and works like the one in a gen. The decision to use less quality parts is what i think not what customers want and will only widen the gap between Chinese watch industry and Swiss again.

Great input Timemaster :thumbsupsmileyanim:

Link to comment
Share on other sites

Thnaks Gran, and while the poll only has 10 votes so far, I think it already shows the ends result - we want ruby jewels regardless of if the metal ones will work sufficiently.

I'm still new here but I think i know this community well enough to know where this will go if the movements continue to use steel. The community will come up with a list or datebase of watches using the ruby jewels, everyone will be informed and sales of the steel jewelled movements will slow.

Link to comment
Share on other sites

Thnaks Gran, and while the poll only has 10 votes so far, I think it already shows the ends result - we want ruby jewels regardless of if the metal ones will work sufficiently.

I'm still new here but I think i know this community well enough to know where this will go if the movements continue to use steel. The community will come up with a list or datebase of watches using the ruby jewels, everyone will be informed and sales of the steel jewelled movements will slow.

Yes indeed mastrmindalliance!!! and lets hope the factories get the message!!!! (BYW it is not steel but metal bearings ;) )

And thanks dluddy :thumbsupsmileyanim:

Link to comment
Share on other sites

"I also would like the Dealers to be honest when they advertise their watches. The question is why they do use metal instead of rubies. As far as I know the rubies they use nowadays are synthetic and very cheap to produce."

Jewels are cheap and as long as they press metal bushing in the plates in place of jewels, there is probably very little actual cost difference. If they start installing pivots in bare holes bored in the plates, they have reached the bottom.

Remember the rolex 1520 'tariff dodger' movements? They used bushings in the autowind assembly instead of jewels to dodge a very small USA tax on imported movements with over 17 jewels.

They worked all right for a while, then the bushings wore out. You see a lot of them in air kings and 5513 submariners with the reversers and intermediate wheels jammed up because the bushings are worn out. Regular service will keep them running for a long time but most owners did not have their watch serviced until it stopped running and by then the bushings may be worn out of round, allowing the wheels to bind.

Many companies use jewel count for prestige...the more jewels, the 'better' the movement. True up to the point of useless cap jewels on every pivot and jewels mounted on winding rotor weights, movement spacers etc. I have a 100 jewel Waltham wristwatch from the 1960s...with 17 working jewels. All the others are there but they just ride around on the winding rotor and spacer.

The autowind assembly has bushings.

"I worked in the computer industry and once was told by a main board engineer that the first design was one of the best. Later designs were stripped en they took as much as possible part of the beards because each of the removed coils, resistors or conductors could bring extra profits as hundred thousands of boards where produced. Some revisions were faulty or unstable because they took of too much components."

Imho, Seiko is a prime example of this in the watch industry. Their quartz movements from the late 1970s and 1980s were great...metal wheels and plates with jewels. You could take them apart to repair them and I have a few from the early 1980s still running strong.

Now they are plastic...plates and many of the wheels. They run a few years then go DOA...no better than a $29 Wal-Mart special.

Many of the old 'metal with jewels' quartz watches are still around but parts are n/a...forcing owners to buy a 'new and improved' model.

The problem with replicas will always be that there are no standards or anything to be governed by. If they can get by with a $13 movement instead of a $15 movement, they will go with the $13 movement.

As for this new chronograph movement...wait and see if Alpha etc uses the low jewel model or a higher jewel model in order to see if a higher jewel version is available.

I noticed swatch has a new eta chronograph movement with just a few jewels too. Maybe this is the beginning of a new trend of cheapness. :animal_rooster:

It can always get worse...

I have an old Bradley 'chronostop' pin lever one jewel chronograph...maybe this type of junk is slowly making a comeback. :(

Link to comment
Share on other sites

  • 1 month later...

The question I have about these new Asian Valgranges movements is what are the hand sizes? Are they the same size as the ETA version, or do we have the same swiss/asian 7750 mismatch issue again? I have a Chopard with one of these movements and I really like the watch, if the hand sizes are the same, I would seriously consider dropping in an ETA version.

Link to comment
Share on other sites

The question I have about these new Asian Valgranges movements is what are the hand sizes? Are they the same size as the ETA version, or do we have the same swiss/asian 7750 mismatch issue again? I have a Chopard with one of these movements and I really like the watch, if the hand sizes are the same, I would seriously consider dropping in an ETA version.

A ETA Valgrange (37mm diamtere) or ordinary ETA (33mm diametre)?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...
Please Sign In or Sign Up