Buffing; Myth or Fact?

[Marc]

I was originally writing this as a response to another post but felt it was going a bit off topic and detracted from the OP's question so I have started another thread. The post that inspired this one is here.

In the absence of any explanation being offered regarding the mechanics of the claim that buffing was a process that removed less material than grinding to achieve the same result by moving metal around to fill a dent in, and given that to me this isn't already well known I decided to spend some time with Google in order to try and secure a better understanding of buffing and polishing. After an hour or so of reading all about buffing wheels, compounds and processes I have to say that nothing that I read from the metals finishing industry or the suppliers of materials to that industry made any reference to the process of buffing moving metal around.

There seems to be a concensus that both buffing and polishing are primarily abrasive processes, and that the differences between the two are that:

• polishing usually involves an abrasive that is bonded to a substrate (paper or cloth for instance) where as buffing involves a loose abrasive in a greasy or waxy carrier which is applied to a wheel, mop, or strop;
• polishing is generally the more aggressive process using coarser compounds and is what you do to remove scratches and surface irregularities prior to buffing to achieve the final finish.

There also seems to be a suggestion that the heat generated by buffing is at best inconsequential and at worst could be detrimental to the process.

I do not claim that my research was exhaustive but it was certainly sufficient for me to conclude that this moving metal around theory is not widely held.

I watched the video "Introduction to Buffing and Polishing" linked in the other thread to see how the magic worked. Two things occurred to me.

One was that the terminologly was reversed; the process of removing the surface irregularities was referred to as buffing, the final finishing was referred to as polishing. This was at odds to everything that I had just read which was a bit confusing.

The second was that if that were my watch I would be very disappointed with the result.

This is the case before the buffing starts. Notice the sharp crisp form of the angle where the side meets the bottom of the case.

This is after buffing and before polishing.

And this is the end result after polishing.

You could hardly ask for a finer example of over polishing and rounding out the original crisp lines of the case. This is the biggest drawback of buffing, the speed at which things can go too far and the proper contours can be destroyed make it a very risky process.

I'm not saying that buffing can't be done in such a way as to preserve such detail, however the fact that a highly skilled instructor at one of the USA's most prestigious watch schools produces a result like this in a demonstration video shows just how easy it is to screw it up.

Using good quality wet/dry paper in grades from 180 grit to 2500 grit double sided taped to a lollipop stick, followed by AutoSol on a rag and then a Selvyt cloth I could have (and indeed have) achieved just as high a polish AND retained the crisp sharp line, and would wager that the difference in the amount of metal removed would be immeasurable if not non-existent.

The drawback of hand refinishing is time. It would probably take me a couple of hours with the wet/dry as opposed to the 25 minutes on the buffing wheel, and that I believe is the primary reason that watch schools teach buffing in preference to hand finishing where ever they can. The watch schools don't just teach watchmaking mechanics, they also provide a grounding in running a watchmaking/repair business, and good business sense says that there is more profit to be made in achieving a good finish in 25 minutes than there is in spending 2 hours getting it perfect, especially if the average customer can't spot the difference.

It is interesting to note that the really high end watchmakers put the emphasis squarely back on the merits of hand finishing. I recall watching a Roger Smith video in which he took 2 weeks to make and finish just one pair of hands. They were perfect though.

[Marc]

Oops, pics didn't load properly and I missed the editing window so here they are;

18 minutes ago, Marc said:

This is the case before the buffing starts. Notice the sharp crisp form of the angle where the side meets the bottom of the case.

19 minutes ago, Marc said:

This is after buffing and before polishing.

19 minutes ago, Marc said:

And this is the end result after polishing.

 

[anilv]

'Good points!

In the example given, the case will definitely benefit from any kind of polishing!

Generally the more expensive the watch, the more you need to be careful with polishing buffing! Some owners prefer untouched cases, warts and all.

Hand polishing will help if you have time and the watch is worth it but to get back the original lines it needs to done with lapping plates and a jig to support the case.

Sandpaper will have a bit of 'give'  even if held parallel to the surface will still round the corner.

Anilv

[Geo]

Marc, thank you for taking the time and effort to compile a post that clearly describes the effects of buffing on a watch case.  If that case had been mine, I would have been furious with the result!

The case in the video could have been refinished correctly, but the time required to do so would not have been cost effective for someone in business.  I use the same method (which I believe I have touched on before in the forum) as you do and have done for years with truly excellent results.

 

 

Edited November 3, 2017 by Geo

[clockboy]

I am not convinced that when I have used the buffing method it has actually moved metal. I suspect it has removed small amounts of metal but during this process has polished giving a very nice and desired effect. However as I have stated in a previous post the removed metal/buffing wax spreads in the air and settles over a large area. I only have a small workshop and therefore I now only polish. I inform any prospective customers of this before a service.

[FlyingWatchmaker]

Can't see the pictures in the first post, but here's my take (17 years watchmaker, 9 years with rlx)

Polishing any metal except platinum removes material..
polishing is the act of replacing deep scratches with small scratches, then replacing those with smaller etc etc,

A buff with compound is just a very soft grinding wheel

For flat surfaces, you can't maintain a flat surface with repeated use of buffing wheels, or hand held emery papers, in the case of rlx professional models, either a linishing belt or lapping disc is used to maintain the flats.

In the case of platinum material is moved around by buffing, though there is grinding as well..

Tom

[Marc]

@FlyingWatchmaker I had issues with the pics not posting in the first post but they are there in the second post.

As both you and @anilv suggested the best way to go is undoubtedly proper linishers or lapping discs combined with dedicated jigs, and there are some truly stunning results to be seen in various forums achieved using this approach.

Hand finishing, if done with care, can get close to these results providing there is no complex graining that needs to be reproduced, and as such it would be quite wrong to dismiss the process as something that should never be done to a watch.

Machine buffing certainly has its place, and in the right hands can produce some excellent results, but as I stated above, the speed at which things can go wrong makes it very high risk.

To me though the argument that buffing is better than abrading (polishing, grinding, lapping, etc) on the grounds that it achieves the same result with less removal of material by moving the metal around is not convincing. I have been unable to find a description of a mechanism that can explain the process in credible metallurgical terms, and none has been offered by supporters of this theory. To me it defies common sense, except perhaps if the effect is on such a nanoscopic scale as to be insignificant.

[mikepilk]

As an engineer and a skeptic, I've never been convinced by the "moving metal" theory ... so I thought I'd try a little experiment :

Note that I only have a hand held "Dremel" type device. I used Dialux Orange, and a hard felt disk.

I filed a groove in to the handle of some stainless steel tweezers. It looks to be about 0.5 mm wide and deep.

I figured that if I applied the felt disk to one side of the groove, if metal is being moved, a lip should form on that side.

After 5 mins of buffing, trying to apply enough pressure to heat the metal (it did get too hot to touch) you can see the results. The wheel is turning in the direction of the red arrow. No lip has formed, and both edges are worn.

After 10 mins, still no lip,  but significantly more wear. 

The thickness at the groove decreased from about 2.65 mm to 2.60 mm

Conclusion. Metal is not being moved, it is being removed.

Maybe someone with proper desk mounted wheels could repeat the experiment to generate more heat and pressure.

 

 

[Geo]

Well done Mike, you beat me to it!

[clockboy]

1 hour ago, mikepilk said:

As an engineer and a skeptic, I've never been convinced by the "moving metal" theory ... so I thought I'd try a little experiment :

Note that I only have a hand held "Dremel" type device. I used Dialux Orange, and a hard felt disk.

I filed a groove in to the handle of some stainless steel tweezers. It looks to be about 0.5 mm wide and deep.

I figured that if I applied the felt disk to one side of the groove, if metal is being moved, a lip should form on that side.

After 5 mins of buffing, trying to apply enough pressure to heat the metal (it did get too hot to touch) you can see the results. The wheel is turning in the direction of the red arrow. No lip has formed, and both edges are worn.

After 10 mins, still no lip,  but significantly more wear. 

The thickness at the groove decreased from about 2.65 mm to 2.60 mm

Conclusion. Metal is not being moved, it is being removed.

Maybe someone with proper desk mounted wheels could repeat the experiment to generate more heat and pressure.

 

 

Yep it confirms my suspicions. 

[hir3na5hra]

I was originally writing this as a response to another post but felt it was going a bit off topic and detracted from the OP's question so I have started another thread. The post that inspired this one is here.
In the absence of any explanation being offered regarding the mechanics of the claim that buffing was a process that removed less material than grinding to achieve the same result by moving metal around to fill a dent in, and given that to me this isn't already well known I decided to spend some time with Google in order to try and secure a better understanding of buffing and polishing. After an hour or so of reading all about buffing wheels, compounds and processes I have to say that nothing that I read from the metals finishing industry or the suppliers of materials to that industry made any reference to the process of buffing moving metal around.
There seems to be a concensus that both buffing and polishing are primarily abrasive processes, and that the differences between the two are that:

• polishing usually involves an abrasive that is bonded to a substrate (paper or cloth for instance) where as buffing involves a loose abrasive in a greasy or waxy carrier which is applied to a wheel, mop, or strop;
• polishing is generally the more aggressive process using coarser compounds and is what you do to remove scratches and surface irregularities prior to buffing to achieve the final finish.

There also seems to be a suggestion that the heat generated by buffing is at best inconsequential and at worst could be detrimental to the process.
I do not claim that my research was exhaustive but it was certainly sufficient for me to conclude that this moving metal around theory is not widely held.
I watched the video "Introduction to Buffing and Polishing" linked in the other thread to see how the magic worked. Two things occurred to me.
One was that the terminologly was reversed; the process of removing the surface irregularities was referred to as buffing, the final finishing was referred to as polishing. This was at odds to everything that I had just read which was a bit confusing.
The second was that if that were my watch I would be very disappointed with the result.

This is the case before the buffing starts. Notice the sharp crisp form of the angle where the side meets the bottom of the case.

This is after buffing and before polishing.

And this is the end result after polishing.
You could hardly ask for a finer example of over polishing and rounding out the original crisp lines of the case. This is the biggest drawback of buffing, the speed at which things can go too far and the proper contours can be destroyed make it a very risky process.
I'm not saying that buffing can't be done in such a way as to preserve such detail, however the fact that a highly skilled instructor at one of the USA's most prestigious watch schools produces a result like this in a demonstration video shows just how easy it is to screw it up.
Using good quality wet/dry paper in grades from 180 grit to 2500 grit double sided taped to a lollipop stick, followed by AutoSol on a rag and then a Selvyt cloth I could have (and indeed have) achieved just as high a polish AND retained the crisp sharp line, and would wager that the difference in the amount of metal removed would be immeasurable if not non-existent.
The drawback of hand refinishing is time. It would probably take me a couple of hours with the wet/dry as opposed to the 25 minutes on the buffing wheel, and that I believe is the primary reason that watch schools teach buffing in preference to hand finishing where ever they can. The watch schools don't just teach watchmaking mechanics, they also provide a grounding in running a watchmaking/repair business, and good business sense says that there is more profit to be made in achieving a good finish in 25 minutes than there is in spending 2 hours getting it perfect, especially if the average customer can't spot the difference.
It is interesting to note that the really high end watchmakers put the emphasis squarely back on the merits of hand finishing. I recall watching a Roger Smith video in which he took 2 weeks to make and finish just one pair of hands. They were perfect though.

Picture links are broken I'm afraid. Wonder if it's because I'm on mobile...[emoji848]

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[hir3na5hra]

Picture links are broken I'm afraid. Wonder if it's because I'm on mobile...[emoji848]

Sent from my SM-G935F using Tapatalk

Ignore! Saw the second post! Sorry!

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[measuretwice]

1 hour ago, mikepilk said:

As an engineer and a skeptic, I've never been convinced by the "moving metal" theory ... so I thought I'd try a little experiment :

 

Well done and thanks for doing so.   

[Tim]

The only time metal is actually "moved" around is with softer metals. Whoever suggested this was perhaps referring to gold, silver, copper, aluminum, or brass. Once you hit steel and other iron derivatives, any work on the metal will remove material. It only makes sense if you think about it, since any of the iron based harder metals have a crystalline structure. When you break the bonds that are holding the structure together — that's it, is gone sooner or later. That crystal-like structure is formed at high heat as the iron cools and forms a lattice.

The key attribute that allows metal to move around is that the metal has to be ductile and malleable at ambient temperatures. Once you have to heat it to achieve any pliability, you are using heat to disrupt the bonds forming its structural lattice. Annealing steel loosens the bonds holding the lattice together. Tempering tightens the lattice.

With steel, polishing should only be the last few finishing steps. Polishing is merely the application of finer and finer scratches. The jagged surface of scratched metal diffuses reflected light by reflecting it in multiple angles.placing finer scratches on the surface is almost like focusing reflected light. The finer scratches go from light being reflected before like this:  \/ . As you place finer scratches, the reflected light pulls in closer and closer to this: || . And that is what makes it appear shiny and brilliant. 

[jdm]

21 hours ago, mikepilk said:

I filed a groove in to the handle of some stainless steel tweezers. It looks to be about 0.5 mm wide and deep.

That damage is well outside the possibilities of buffing repair. On such a deep grooves, miracles are not possible, neither claimed anywhere, and you have wasted time, Dialux and a pair of tweezers in just trying. 

Really seems like people here haven't grasped that the subject of all this is repair of 'normal' dings and scratches, Also, generally a Dremel turns too fast for proper buffing, where the speed has to be low, however using a small wheel helps as it keeps the linear seeps lower.

Then regarding Marc's posting, first of all the naming of buffing and polishing in the school's video is absolutely correct in the context of watch case work and jewelsmithing. For example:

rouges are typically used for polishing and finishing work whereas the tripoli compounds are used for cutting and buffing to remove scratches from the metal.

https://blog.esslinger.com/guide-to-buffing-compds-and-their-uses/

However, in automotive painting, and possibly other crafts, the two terms are reversed. So you have to do searches in out specif context to get applicable results.

Also I I'm under the impression that Marc went to attack that case with the purpose of demonstrating his pre-concepts, that is reduced to blanket statement that "buffing ruins edges". Of course it does, when done incorrectly as above.

What works for me instead is to use the small and thin wheel, so that i doesn't go around the edges. as you apply pressure. And I try to concentrate pressure and passes on exact spot of damage, rather than work all around. I believe I could have got much better results from the same starting damage in picture.

However, as I've said that already, countless other established sources confirm how the fine practice of buffing is done, and its results. If others prefer to remove half a mm of metal all around in order to fix a 0.1mm ding, using abrasives more apt for masonry, and then working countless wet passes and tool changes, I couldn't care less. And I still have to see of someone with "proper linishers or lapping discs combined with dedicated jigs", especially when it comes to repair common man watches. Also the suggestion of "laser welding" made in other threads is kind of laughable for me, as for example in my "1st world" country I can't find a decent welder for large pieces, go figure micro-welding.

So. All I know is that I can repair most of damage to SS cases using proper buffing and polishing, and I have posted my results on various occasions. Perhaps I will do again as long, even if that will make people turning blue in the face to demonstrate that I can't 

 

 

 

 

 

[Geo]

Aye whatever!

[jdm]

1 minute ago, Geo said:

Aye whatever!

Seems like having dismissed the Mod's hat makes the raw George come out  better 

 

[mikepilk]

31 minutes ago, jdm said:

That damage is well outside the possibilities of buffing repair. On such a deep grooves, miracles are not possible, neither claimed anywhere, and you have wasted time, Dialux and a pair of tweezers in just trying. 

 

 

 

 

 

 

I wasn't trying to demonstrate the repair of a scratch. I created a deep groove to try to show if any metal was moved over the edge to create a lip. It wasn't. 

Whether you want to call it buffing or polishing, on hard non-malleable metals like stainless steel, they both just remove metal, not move it.

[Tmuir]

Micro welding is a viable option to repair large dents and scratches in watch cases, but I agree not for most of us. Not only for the cost of the tool but for the skill involved to use it properly too

One of graduates of the watch school I attend makes his living restoring high end watches and refinishing cases.

Hodinkee did an article on a case he refinished for them. The deliberately gave him a very beat up watch to restore.

Have a look and see for yourself.

https://www.hodinkee.com/articles/the-inside-and-outside-restoration-of-a-doxa-300t-searambler

Yes I know this post is taking a bit of a tangent from what the thread is about, but it demonstrates another way to repair / restore / refinish a watch case.

[jdm]

Just now, mikepilk said:

I wasn't trying to demonstrate the repair of a scratch. I created a deep groove to try to show if any metal was moved over the edge to create a lip. It wasn't. 

Whether you want to call it buffing or polishing, on hard non-malleable metals like stainless steel, they both just remove metal, not move it.

Your experiment was made 10 times off the scale of practical SS buffing. As if one tries to demonstrate liquid capillarity in a 10cm pipe.

However I won't be dragged furthermore to this, it works for me and for anyone that does it correctly - we aren't all crazy, you know. Disbelievers are welcome to keep grinding  

[mikepilk]

4 minutes ago, jdm said:

Your experiment was made 10 times off the scale of practical SS buffing. As if one tries to demonstrate liquid capillarity in a 10cm pipe.

However I won't be dragged furthermore to this, it works for me and for anyone that does it correctly - we aren't all crazy, you know. Disbelievers are welcome to keep grinding  

That sounds a bit like special pleading!

If it only works on a scale 10x less, then you can't possibly tell if metal is being removed, not  moved.

Until someone comes up with some concrete evidence, I'm sticking to my  working hypothesis :

Buffing/polishing of stainless steel does not move metal, it only removes it.,

[measuretwice]

1 hour ago, jdm said:

So. All I know is that I can repair most of damage to SS cases using proper buffing and polishing, and I have posted my results on various occasions. Perhaps I will do again as long, even if that will make people turning blue in the face to demonstrate that I can't 

I don't think anyone is suggesting you don't get great results, not from me anyway.  I don't see this content as comment on anyone's skill, only the underlying physics and engineering on what is happening and the discussion around the possibility of moving SS about with buffing.

I aspire to have a scientific mind.  That imposes the requirement that one should never take it personally to find out they were wrong and never dogmatically get invested in ideas and beliefs such that they cling to them contrary to evidence and science.   So....if anyone can take a piece of SS, grind it perfectly flat so it reads dimension X measured everywhere over its surface by accurate measurement (ie comparator or quality mic)....and then, by buffing only, make  a part of thicker, I'll will unabashedly abandon the science I think I know and be a believer.   If it was possible to move SS around, I'd have thought it to be well known and appear in a variety of manufacturing and engineering instances.  As there is no science or engineering I can find suggesting its at all possible, and is in fact is quite contrary to what I do know about the property of materials, its bit like asking someone to believe in ghosts.... until there is some evidence or even the good description of a plausible mechanism (a theory) its hard to accept.

Edited November 4, 2017 by measuretwice

[Neileg]

If you want sharp crisp detail on your watch with no scratches or dings, leave it in the box.
If you wear and enjoy your watch it will get scratched, dropped, banged against things and show signs of use. You can then make a choice, polish it and make it shiny again or live with the patina. What you can’t do is make it look new again.
Enjoying my watches every day...
Neil


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[Neileg]

If you want sharp crisp detail on your watch with no scratches or dings, leave it in the box.
If you wear and enjoy your watch it will get scratched, dropped, banged against things and show signs of use. You can then make a choice, polish it and make it shiny again or live with the patina. What you can’t do is make it look new again.
Enjoying my watches every day...
Neil


Sent from my iPhone using Tapatalk

[hir3na5hra]

Your experiment was made 10 times off the scale of practical SS buffing. As if one tries to demonstrate liquid capillarity in a 10cm pipe.
However I won't be dragged furthermore to this, it works for me and for anyone that does it correctly - we aren't all crazy, you know. Disbelievers are welcome to keep grinding [emoji3] 

So basically all the watch houses known on earth have been doing it and getting it wrong. And the only "correct" way is your inconceivable technique.... Riiight.

By the way, I thought you left this group after Mike debunked your technique?

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