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Here link Stas's tool drawing by Russian
https://workspaces.acrobat.com/app.html#d=6ZUCQcGBaCQZW8pJyQvV0w

Max, shaping hammers is done by modulating pressure and shape of the sanding strip with the fingers or the pressure of the sanding pad.

the angled hammers are hold by hand to avoid pushing on the centers too much, anyway a sanding paper is a cutting machine that does not need much pressure if good and sharp.

holding a long tool may not allow much sensitivity, we need to feel what happens and visually check on both sides.

Thank, Isaak I'm be think about your words.
I have one question:
it's links work?

yes , may be only when signed to Adobe.

nice design but I do not believe in the use.

Learning to shape correctly hammers is one of the skills one need to learn by practicing.

pressure is applied on the spot we want to work so it goes all around, in different places until the top sanded very ligtly or not at all with the heavy papers.

having that sort of control with a tool is difficult (with the one using a Dremel as well)

When gang filing the fingers take the wanted shape.

Beginning low allow to have a sharp enough shape. sanding high make a round shape (pear style)

Isaac,

In all of your pictures above, the shape of the hammer, at least between 9:00 and 15:00, very neatly follows the shape of the underfelt - or, where there is no underfelt, the hammer's shape follows the shape of the wooden molding.

Is this generally-accepted best practice?

The less the fiber is cut the better, mostly if one make a sharp shape from a round molded felt, the shape does not hold well in time.

Hence the advantage to use hammers intended for the brand/model, or something similar.
It may have more to do with the way the felt like is cut than with the pressing, may be.

Thank, Isaac. I fully agree with your comments about the top layer of felt when we are removing the felt with a hammer. However Stas wrote to me that the mechanism moves smoothly. It is only correct necessary to change the fine-grained sandpaper

Tape device for grinding of a hammer with an electric motor by Russian technician Stas Cukanov

definitively heavy

If I where to use the wooden one, I first need to learn where is the contat point and how to locate it on the zone of the shoulders I want to work.

Then keeping the handle in the axis of rotation plane around the hammer is the goal (as with the handle you cannot really feel/perceive the side of the hammer well you have to imagine the squareness - also if one have to push on the hammer laterally the centers suffer)

Even with the small sanding blocks that have a "wall" I am never sure I am applied on the flat side correctly, I can imagine how whith a long handle the sensations are almost nil.

I use a simple method of the same system with a flat stick having the strip attached to only at the extremity.

The stick allow to attain the underside of the hammers on vertical pianos and orient the strip. the other hand pull the strip - can be used as a standard sanding file too.

strips changed easily as they are backed with 3M type scratch (sanding paper specific for lacquers, white color, lubed), not as aggressive that some others but I keep it for the scratch.


I just copied a factory tool used by Yamaha.

%

This electric device would have to be even worse than the hand-operated one in terms of destructive potential. What I think would be interesting is if he made a model with interchangeable rigid races/guides which can hold the sandpaper in the proper egg shape. You could have a range of profiles to suit the application.

Of course, the biggest problem is that it's really not that hard to file them by hand and you can see how the shaping is progressing much more easily.

Thank you for your explanation, Isaac. I will certainly pass on your wishes Stas upgrading the device-to-point contact about. Where and how it's feel?
Isaac if I understand you correctly, in this model have the negative side:
it's a long handle, which has a low sensitivity "zero"
I would like to see (foto or video) a copy of your Yamaha device if possible

Dear ando can not agree with you that a new electrical device Stas be more damaging to the manual. The main negative point of destruction fiber portage in my opinion is a standard emery tape and the speed turn of one cycle.
Egg-shaped, with interchangeable rigid races/guides will find in the job of a device if it's will need

Maximilyan,

Long time no talk. You are doing a great promotion for your friend. Wish I had a friend like that. No doubt that he is on his way to design a great tool that has a great concept and potential. Don't be surprised that many will find numerous imperfections with this current prototype. Its just a matter of time to figure out its flaws and perfect it and bring it to best possible performance and efficiency.

I personally like all the mechanical devices, especially this simple device that your friend came up with, seems like an easy tool to repair and make yourself. People who strive for new ways to accomplish precision in piano restoration, are all contributing to keeping piano restoration trade alive.

All in all, no matter what anyone says this device represents the history of development of technology and I forsee that eventually will be part of the exhibit in the museum of the history of piano restoration. Don't you think?

Best regards and always glad to read your postings!

Gene is very happy to read any message from you. Yes are you really have not been heard long time. Stas has undergone massive criticism in Siberia for their pioneering development tool. I like that believe that this device has a right to exist, and in the long term can help as amateurs and professionals in the servicing of piano hammers.
It can not be modest but there is help in the province from corrugated cardboard for the treatment of pins. And I'm happy about that yet another 'Belarus' lives
Regards,Max

Генадий, очень рад читать любое сообщение от Вас. Да действительно Вас давно не было слышно. Стас подвергся массированной критике в Сибири за свои новаторские разработки оборудования. Я как и Вы считаю, что подобное устройство имеет право на существование и в перспективе способно помочь любителям и профессионалам в обслуживании молоточков пианино.
Это быть может не скромно, но ведь помогает же в провинции гофрокартон для лечения колков. И я рад этому, что ещё одна "Беларусь" продолжает жить!

I would work on a device that could be hand held (no handle)

Technological tools care useful when they allow easier work or faster.

But traditional technology solved much of the problems and include gesture that cannot easily be reproduced by machines.
As tuning for instance.

Most of what we do is based on limited tools and maximum training.

Now nice tool are cool...

But I like to work with a minimum, even if I sort of collected gadgets for some time.

I appreciate mechanical tools that can do something that cannot be done another way.

A good itinerant tech can do a lot of things at a good quality level, with not so heavy tool bag. (and some hide all tools but the one used)

I would work on a device that could be hand held (no handle)

Technological tools care useful when they allow easier work or faster.

But traditional technology solved much of the problems and include gesture that cannot easily be reproduced by machines.
As tuning for instance.

Most of what we do is based on limited tools and maximum training.

Now nice tool are cool...

But I like to work with a minimum, even if I sort of collected gadgets for some time.

I appreciate mechanical tools that can do something that cannot be done another way.

A good itinerant tech can do a lot of things at a good quality level, with not so heavy tool bag. (and some hide all tools but the one used)

Hammer shaping is more like the art of sculpting. This makes the use of machines in achieving a satisfactory final result, problematic.

The difficulty with the Russian prototype is that it's crown-driven or activated as opposed to shoulder. This will invariably result in a disproportionate hammer, not to mention being hard on the crown itself.

The benefit to the invention is that hammers can be shaped without removal from the rail. It, therefore, has potential to be a great time saver if developed properly.

In looking at the drawing of the electrical prototype, it is difficult to see how it could be changed to shoulder driven. However, if there was a way to protect the crown, it might work. I am no inventor. But if I were to use something akin to this proposed tool, at the very least it would be helpful to have:

1. Transparent casing to see work in progress.
2. Variable speed.
3. Forward and reverse switch.
4. A mechanism to protect the crown as the machine sands up one shoulder and then up the other.

Moreover, as it is, the prototype cannot be used safely on hammers in the high treble. The user will be looking at wood before he realizes it.

Some of us with much practice learned how to shape hammers properly on the main rail and with a common electrical device: a variable speed dremel. With a keen eye for symmetry, and an exceedingly steady hand, good work can be effected whilst protecting the crown. Simply sand up one shoulder toward the crown, and then the other. But one slip or sneeze, and the hammer is damaged, sometimes beyond repair.

In this context what would be helpful is a device that eliminates the need for a steady hand, onto which a dremel or something similar could be attached and be guided by the watchful tech. (The Russian prototype may assist in steadying the hand, but only to a minor extent.)

The Russian tech is to be commended. I hope he continues in the lab and finds a way to develop the concept in such a way that all techs everywhere can both applaud his effort and use his invention.

Until that time, however, the time-tested sanding with paddle is by far the best and safest method.

Bob, thank you for taking the time to understand the essence of the device Stas. I also hope that Stas will improve their own device. I shall present yours proposal (4)
1. Transparent casing to see work in progress.
2. Variable speed.
3. Forward and reverse switch.
4. A mechanism to protect the crown as the machine sands up one shoulder and then up the other.

Regards, Max

Bob I have seen a sort of lip that can be installed on a flexible Dremel (the pro ones, with a pedal)

The guide is sort of helping, the flexible have some self inertia but tend to move when the speed change.

It is not very easy to use as one do not feel corretly what happens to the hammer.

A moving strip should be better but there also, even with transparent casing, one would need to raise the tool regularely to see what is going on.

Or work in blind mode and that, I cannot acept on hammers.

Hello,Isaac

"a flexible Dremel" What this? Have you a foto or a video?