Bosendorfer pianos can seem a bit mysterious to technicians in the U.S. I know I don’t see very many. They have some unique features like double flanges damper blocks (they hinge front-to-back and left-to-right). They also feature cheek blocks with capstans. One on the front facing down and one in the rear facing back.
First you need to make sure that the glides are bedded, which could be a whole article unto itself. If done properly the front should knock at key 1 and 88. The cheek block’s down facing capstans are intended to put just enough pressure on the front rail at those point to keep them from knocking once the cheek blocks are tightened. The rear capstan is to put just enough pressure on the key frame to snug it up against the dags but still letting the frame shift smoothly.
With a capstan wrench, adjust the front capstan so the front rail no longer knocks when the cheek block is in place and tightened. The rear capstan is the same idea but instead of looking for knocking, grab the stack gently pulling the action front to back. The rear capstan should be adjusted so that there’s no play as you pull on the stack. Be careful not to over pinch the keyframe so that the action shift is affected.
I should’ve taken photos of the cheek plates. They’re unique as well. If you have some experience with them, leave it in the comments.
I love it when I find a great tool. I love it more when I discover that a tool I already own can do more than it was designed for. Such is the case with Scortino Coil Maker tool.
If you were to search for piano stringing tools on the web you’d find a wide assortment of coil makers, becket tools, pliers, pin drivers, and punches. But one tools you won’t find is a Hitch Pin Knot tool. They don’t exist. My good friend and mentor Paul Bruno made one from scratch and it’s the only one I’ve seen… Until now.
The Scortino Coil Maker
Pictured to the left is the Scortino Coil Maker (and a pair of pliers, but ignore the pliers). It’s one of the best and most compact coil making tools I’ve ever used. It’s inexpensive. And.. it also makes for a first rate Hitch Pin Knot tool.
The finished Knot
Pictured to the right is what we want to end up with. Here’s how we get there.
First we remove the large screw from the backend of the tool (photo A). On the top of the tool there’s a black set screw normally used for coiling but we’re going to use it for making the initial loop (photo B). Once you’ve got a nice loop, insert the blank end of the wire down through the hole so the loop sits at the top (photo C). With pliers grab the loop and turn, making sure the tail gets caught at the set screw (photo D). You’ll need to push down as you turn to get a tight winding, however, if needed you can tighten the winding once the string is on by tapping the windings together with a brass rod or hammer shank. Make sure to get 5-7 windings and then trim the tail.
When you put on the string you’ll need to account for the excess slack from the knot tightening as you put tension on it. Instead of cutting at “3 fingers length” try “2 fingers”, and use the Scortino tool to make a coil with only 1 1/2 coils not 2 1/2. When you’re done, enjoy your nice looking knot (photo E)… and your new Hitch Pin Knot making tool.
I was just recently preparing Yamaha CFIIIS for Simone Dinnerstein and got a note from her that the 6th octave didn’t have enough sustain. I’d like to outline what I did to address the issue.
First I Checked the Regulation
I made sure that the let-off was close but not so close that it could block even in the slightest and potentially dampen the tone. Next, I checked the hammer fit to the strings. I blocked the hammer to the strings by pressing up on the jack at the tender joint and made sure that all of the strings were muted equally when plucked. I checked the key frame bedding to make sure it was solid. I even tightened the action screws on the rails and the brackets. Lastly, I seated the strings to the bridge and even massaged the strings with a spinet shank. Since none of these actions yielded a substantial result the next thing to do was to inspect the hammer.
It Could Be the Hammer Then
I say “inspect” because if the timbre of the hammer is pleasing then something related to the mechanics of the hammer might be the issue. By squeezing the hammer in the upper shoulders and also in the lower half by the staple you can get a sense of tension in the felt. You can also get a sense of how much needling the set of hammers has seen. When I squeezed the lower area by the staple I could feel that it was soft. My suspicion was that the hammers in this octave were a bit weak and so the lower area was “needled up” to increase their tone. A side affect of that particular voicing technique is a loss of dynamic range and potentially some sustain as well.
The Juicy Part
Since you can’t add tension back to a hammer, the only left to do in this case is juice the area. The idea here is to reinforce the felt fibers. Imagine that the hardener is coating the felt fibers and stiffening them. That’s how we can get some tone back. I’m going to use plastic (PMMA or “poly methyl methacrylate”) and acetone. You’ll want be sure that your mixture looks similar to skim milk.
I concluded earlier that the bottom half of the hammer is too soft so I’ll juice the lower hammer area by the staple and not any higher than 3 and 9 o’clock. Notice that these hammers have a reinforcement from the factory. That can potentially limit how effective our juicing will be (It’s worth mentioning that needling the reinforced area of a hammer also produces limited results).
In this case it was enough and the artist was satisfied with the results. The juicing in combination with voicing for evenness did the trick.
The next time you run into funky bi-chords and tri-chords in a piano’s bass section that just won’t go into tune, this quick tip can help you deal with them.
This trick is for bass strings that have partials that just won’t go into tune. Instead of playing the note and trying to weed through a stack of partials, let’s isolate the one you actually want to tune. I find that in the bass section it’s the 4th partial that works best. If you’ve got Tunelab or another ETD that you can select the 4th partial, just tune each string to the machine.
If you tune aurally, you can use your finger to activate the 4th partial (or any other partial that helps). While playing the note, lightly touch the strings and search for a partial that’s a double octave. The piano in this photo is about 5ft long so the spot is behind the dampers but on a concert piano it would be in front.
Once you’ve got it, tune the unison by listening to the partial. If you get the partial sounding good but the unison doesn’t sound good, look for another partial like the 5th. The idea is to single out the partial that’s going to help you get as clean a unison as possible.
It’s all over. I’m back home. My tools are back in the car. The 2012 PTG Convention has faded to an echo in my mind. All there is to do is to relive it all over again!
Wednesday, July 11
8:00am – Written Exam – Passed (yay!)
10:30am – “On Pitch” with Rick Baldassin (posted here)
1:00pm – Tuning Exam – Passed (double yay!)
Thursday, July 12
8:00am – “Steinway Action Rebuilding” with Kent Webb (posted here)
1:30pm – “Grand Dampers Demystified” with Baldassin. Teel, and Spreeman (posted here)
Friday. July 13
8:00am – “Heart of the Hammer – The Art of the Bump” with Fred Redekop (posted here)
10:30 am – “Grand Action Regulation and More” with Eric Schandall (posted here)
1:00 – Technical Exam – Passed (triple yay!)
8:00am – “Voicing the Renner Blue Point Hammer” with Baldassin and Spreeman (posted here)
1:30pm – “New Hammer – 6 ways to go” with Norbert Abel (posted here)
And let’s not forget the exhibition hall…
A Ravenscroft 7ft
Randy Potter – I’m a graduate of his school.
Robert Scott – creator of Tunelab
Jack Brand – Owner of the Wurzen Felt Company, maker of Weickert Felt
Sandy Roady – PTG Membership / Convention Manager
Norbert Abel was on hand at the convention to give a great overview presentation of the Abel company’s products and services.
Norbert started with basic hammer felt construction showing slides of the felt factory that Abel buys their felt from. Seated behind me was Jack Brand from Wurzen (also owner of Wiekert) so I got some extra info about the factory slides.
The point of the class was to show how Abel not only provides new hammers but also replacement and replication services. From square grand hammers to odd moldings it seemed that wasn’t anything they can’t replicate.
Custom hammers isn’t a large business for most technicians. But if you’re rebuilding a piano from a brand long since out of business, Norbert showed that the hammer services from Abel make it possible to be able get the right hammers for the job.
Renner Hammers, Rick Baldassin, Micheal Spreeman and Ravenscoft Pianos… This is going to be good.
And it was! Rick and Micheal spent 2 class periods demonstrating their voicing techniques on a new Renner hammer called the Renner Blue Point. They are the next generation Renner hammer following the Renner Blue. What’s new about them? The are actually pointed but not by filing. The pointed shape is actually pressed into the hammer. They also use a special felt from the Wiekert felt company. Wierkert felt is responsible for the classic American piano sound from the early 1900′s. And it’s back.
(Sorry for the blurry photo)
As if this wasn’t enough, there was a special guest that I ran into on the way to the class. It was Jack Brand, owner of the Wurzen Felt company which manufacture Wiekert felt. Jack’s passion for piano hammer felt absolutely permeated the room. He gave a detailed account of the history of Wiekert, how he came to know about them, and his pursuit of buying the Wiekert company and restoring it’s former production methods.
He talked about how while Wiekert was only a small percentage of the Wurzen comapny (and their only piano related felt) it required 90 percent of their R&D. What they learned from making hammer felt at Wiekert, however, improved every other department in the Wurzen factory.
Rick and Micheal apparently like the Wierkert a lot because it’s the only hammer felt that makes it into Ravenscroft pianos. Their voicing techniques and friendly banter made for an enjoyable class.
Here’s a photo gallery from the presentation: