Usually, I wear a dust mask, and I do highly recommend that. I wasn't wearing one for this video because I was talking for the camera. But a mask is important because wool fibers can cause respiratory distress. I am allergic to wool, so it goes without saying that I use a dust mask. My hands still suffer from cracked skin, though.
I've never used this method myself - nor have I ever seen this done in this this way before. Moreover, my copy of the piano tuner's 'bible' - Reblitz - makes no mention of this either. I guess I'd have to try it for myself in order to see if it actually works. My own method is as described by Arthur Reblitz, using a hand-held sanding block. I should add that I have 46 years' experience working as a piano tuner/technician.
For grits of paper, I use four grits of wet-or-dry paper: 220, 150, 400, and 600. (Of course, I don't use the paper wet.) This is for current vintage Steinway hammers (2017). Steinway hammers in the 1990's were in transition from the type with the gray shoulder dye to the clear white felt we now have. These hammers were not quite as dense as today's hammer and could be filed with coarser grit, like 150, and even 80 or 60, depending upon the amount you wanted to pull off. For all hammers pre-1984, with gray dye on the shoulders, I usually started with a 60 grit and progressed up to 220. These were the exceptionally light hammers (2 grams lighter on average) Steinway used to make all the way back to the early 1900's.
Hi Robert, thank you so much for your information on the history of the steinway hammers. Do you happen to know if steinway factories (Hamburg and New York) used similar hammers pre-1970?
Hello Robert, thanks for your video. I am looking for information which I cannot find in any books or videos I have been watching, so I'm seeking your advice please. I am rebuilding a 6' Bechstein Grand. I had a company replace all the hammers and glued new shanks. Now that these hammer/shank assembly have been reinstalled, I need to check the travel of each hammer to the strings. Before doing this, should the hammers be vertical to the strng, then set the travel or is it more important to make sure that the hammers strike the string at 90 degrees? I have set the hammer AO vertical, but when lifting to the string, there is side travel. Before setting this hammer vertically, there was less side travel. This confuses me. Where do I start...? Thanks for your help
I travel hammer shanks before I glue on the hammers, but I understand that you had new hammers and shanks sent to you pre-assembled. In the case that I received hammers and shanks pre-assembled, I install them on the action frame and travel them right away. After traveling, I check for hammers that aren't vertical and use a heat gun (or alcohol lamp) to "burn" the offenders vertical again. This is an important step before filing, because if a hammer or hammers aren't perfectly vertical before you begin filing, then you're going to get a skewed strike surface. When it comes to hammers that are angled, I file them one at a time with narrow strips of sandpaper. I didn't show this in this particular video because it was only a casual video demo intended for my sister-in-law. The process is much the same during single hammer filing. Somewhere in my videos I have on on traveling.
Hello Robert, Nice Videos, thank you! I would like to know if you have any experience with Schimmel Konzert Piano Hammers I need to know if the hammers on those pianos are designed to be juiced for tone building
Hello Fernando, I have never worked with the hammers you mention. However, if they are anything similar to the Renner hammers used on Bösendorfer, they can be juiced. The techs at Bösendorfer in Wiener Neustadt (the factory) use a concentration of 8:1 lacquer on their hammers as needed. That can give the hammers a tonal boost. If I were advising you, I might suggest you try that concentration first. If it doesn't have the desired effect, then try something like 5:1. Mind you, we're talking about thinner:lacquer. I can't recall whether they used acetone to cut the lacquer at Bösendorfer. It probably is lacquer thinner, and the lacquer is nitrocellulose wood lacquer. Personally, I prefer to use acetone to cut my lacquer. (This gives me the idea that I ought to do a short video on lacquering Steinway hammers...something for me to think about...)
Robert Grijalva thank you very much Robert!! I appreciate your kind reply and will follow your advice. I will check alignment and strike points first and will also try your shaping technique as well.
The direction of filing any hammer is a matter of the nap of the felt. Some hammers file better in one direction, as I do in this video. However, filing upward works less well on contemporary NY Steinway hammers. In 1984, Steinway reformulated their hammers and went away from the super-soft grey-edged hammers. The grey-edged hammers responded better to the two-sided technique. Current hammers, which have been refined and steadily improved in the last 20 years, seem to have a shorter, and more dense felt that requires filing in one direction with straps rather than paddles. In my experience, the one-direction strapping produces a finer appearance, as with these in the video. Thanks for your question!
I tried one direction sanding on my Abel naturals, but in the treble, the felt at the back became really fuzzy. I tried sanding upwards to get rid of the fuzz, which did flatten down some of it, but then there was a ‘line’ of fuzz near the crown which cannot be removed... 🤔 I am puzzled
I apologize that I haven't replied sooner. Regarding your Abels; they are of a different construction than a New York Steinway hammer. They are more similar to the Hamburg hammer, which is made by Renner. In this case, you did the right thing to fill upwards on the rear side of the hammers. Some hammers do file better like that, and you simply meet at or near the crown to get the front and back "layers" aligned. The fuzz that resulted during your Abel filing may also have been caused by using too coarse a grit on them. I have found that with European hammers, using the finer grits is best. Instead of starting with something like a 150, I start instead with 250, then progress to 400 and 600. I may even start just with the 400, depending upon the amount of hammer wear. Of course, all this is generalized info. You have to experiment a bit to find the best combo of grits and technique to file the hammers you have at hand. Best of luck!
Like most UK and European tuner/technicians, I always use Abel Natural Felt hammers whenever installing new hammers on a piano - they have become the industry standard on this side of the Atlantic. Thus far, I have had no need to reshape them, given that most piano owners do not practice for 7 or 8 hours per day for 6 days per week, and therefore they are not yet worn down..! As per my comment of this video, I myself have never even seen this method of reshaping hammer felts, and there is no mention made of it in Reblitz. I may try this method at some point, but there's no way I'd experiment on a customer's piano. I've been a tuner/technician for 46 years, and I err on the side of caution...
Thanks man. yours is the third video I've watched of people reshaping hammers and this is by far the best/fastest technique. I will be doing this.
Thanks! Great Video. I sneezed all the way through it just watching that felt dust!
Usually, I wear a dust mask, and I do highly recommend that. I wasn't wearing one for this video because I was talking for the camera. But a mask is important because wool fibers can cause respiratory distress. I am allergic to wool, so it goes without saying that I use a dust mask. My hands still suffer from cracked skin, though.
I've never used this method myself - nor have I ever seen this done in this this way before. Moreover, my copy of the piano tuner's 'bible' - Reblitz - makes no mention of this either. I guess I'd have to try it for myself in order to see if it actually works. My own method is as described by Arthur Reblitz, using a hand-held sanding block.
I should add that I have 46 years' experience working as a piano tuner/technician.
For grits of paper, I use four grits of wet-or-dry paper: 220, 150, 400, and 600. (Of course, I don't use the paper wet.) This is for current vintage Steinway hammers (2017). Steinway hammers in the 1990's were in transition from the type with the gray shoulder dye to the clear white felt we now have. These hammers were not quite as dense as today's hammer and could be filed with coarser grit, like 150, and even 80 or 60, depending upon the amount you wanted to pull off. For all hammers pre-1984, with gray dye on the shoulders, I usually started with a 60 grit and progressed up to 220. These were the exceptionally light hammers (2 grams lighter on average) Steinway used to make all the way back to the early 1900's.
Hi Robert, thank you so much for your information on the history of the steinway hammers. Do you happen to know if steinway factories (Hamburg and New York) used similar hammers pre-1970?
Many thanks teacher.
Thank you for showing this.
thanks...worked out great. Not sure why the RPT's scare people from doing this; although, it does take skill
I belive, Steinway T-short may help to make good job!
Hi. What grit and type of paper are you using? What number paper for the final smooth file?
Hello Robert, thanks for your video. I am looking for information which I cannot find in any books or videos I have been watching, so I'm seeking your advice please. I am rebuilding a 6' Bechstein Grand. I had a company replace all the hammers and glued new shanks. Now that these hammer/shank assembly have been reinstalled, I need to check the travel of each hammer to the strings. Before doing this, should the hammers be vertical to the strng, then set the travel or is it more important to make sure that the hammers strike the string at 90 degrees?
I have set the hammer AO vertical, but when lifting to the string, there is side travel. Before setting this hammer vertically, there was less side travel. This confuses me.
Where do I start...?
Thanks for your help
I travel hammer shanks before I glue on the hammers, but I understand that you had new hammers and shanks sent to you pre-assembled. In the case that I received hammers and shanks pre-assembled, I install them on the action frame and travel them right away. After traveling, I check for hammers that aren't vertical and use a heat gun (or alcohol lamp) to "burn" the offenders vertical again. This is an important step before filing, because if a hammer or hammers aren't perfectly vertical before you begin filing, then you're going to get a skewed strike surface. When it comes to hammers that are angled, I file them one at a time with narrow strips of sandpaper. I didn't show this in this particular video because it was only a casual video demo intended for my sister-in-law. The process is much the same during single hammer filing. Somewhere in my videos I have on on traveling.
Thanks Robert, much appreciated
Hello Robert, Nice Videos, thank you! I would like to know if you have any experience with Schimmel Konzert Piano Hammers I need to know if the hammers on those pianos are designed to be juiced for tone building
Hello Fernando,
I have never worked with the hammers you mention. However, if they are anything similar to the Renner hammers used on Bösendorfer, they can be juiced. The techs at Bösendorfer in Wiener Neustadt (the factory) use a concentration of 8:1 lacquer on their hammers as needed. That can give the hammers a tonal boost. If I were advising you, I might suggest you try that concentration first. If it doesn't have the desired effect, then try something like 5:1. Mind you, we're talking about thinner:lacquer. I can't recall whether they used acetone to cut the lacquer at Bösendorfer. It probably is lacquer thinner, and the lacquer is nitrocellulose wood lacquer. Personally, I prefer to use acetone to cut my lacquer. (This gives me the idea that I ought to do a short video on lacquering Steinway hammers...something for me to think about...)
Robert Grijalva thank you very much Robert!!
I appreciate your kind reply and will follow your advice. I will check alignment and strike points first and will also try your shaping technique as well.
Nice video. What sandpaper grits do you use?
Isn't backside felt filing in upward motion instead of filing downward?
The direction of filing any hammer is a matter of the nap of the felt. Some hammers file better in one direction, as I do in this video. However, filing upward works less well on contemporary NY Steinway hammers. In 1984, Steinway reformulated their hammers and went away from the super-soft grey-edged hammers. The grey-edged hammers responded better to the two-sided technique. Current hammers, which have been refined and steadily improved in the last 20 years, seem to have a shorter, and more dense felt that requires filing in one direction with straps rather than paddles. In my experience, the one-direction strapping produces a finer appearance, as with these in the video. Thanks for your question!
Robert Grijalva Thanks Bob for detailed answer. I appreciate all your informative videos.
Hi Robert can that technique be used on an upright with the action out of course?
I don't see why not, as long as you provide the proper support to the hammers, and you can get clear of the dampers.
I used some flat sanding sponges from Japan and they work quite well for uprights.
I tried one direction sanding on my Abel naturals, but in the treble, the felt at the back became really fuzzy. I tried sanding upwards to get rid of the fuzz, which did flatten down some of it, but then there was a ‘line’ of fuzz near the crown which cannot be removed... 🤔 I am puzzled
I apologize that I haven't replied sooner. Regarding your Abels; they are of a different construction than a New York Steinway hammer. They are more similar to the Hamburg hammer, which is made by Renner. In this case, you did the right thing to fill upwards on the rear side of the hammers. Some hammers do file better like that, and you simply meet at or near the crown to get the front and back "layers" aligned. The fuzz that resulted during your Abel filing may also have been caused by using too coarse a grit on them. I have found that with European hammers, using the finer grits is best. Instead of starting with something like a 150, I start instead with 250, then progress to 400 and 600. I may even start just with the 400, depending upon the amount of hammer wear. Of course, all this is generalized info. You have to experiment a bit to find the best combo of grits and technique to file the hammers you have at hand. Best of luck!
@@robertgrijalva7158 Thank you!
Like most UK and European tuner/technicians, I always use Abel Natural Felt hammers whenever installing new hammers on a piano - they have become the industry standard on this side of the Atlantic. Thus far, I have had no need to reshape them, given that most piano owners do not practice for 7 or 8 hours per day for 6 days per week, and therefore they are not yet worn down..!
As per my comment of this video, I myself have never even seen this method of reshaping hammer felts, and there is no mention made of it in Reblitz.
I may try this method at some point, but there's no way I'd experiment on a customer's piano. I've been a tuner/technician for 46 years, and I err on the side of caution...