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Reducing Power in a Ronsen Hammer question

  • 1.  Reducing Power in a Ronsen Hammer question

    Posted 07-16-2018 00:28
    So i'm trying the Ronsens VFG felt hammers. This set was very soft. 
    Some basic steps I took:
    Tuned
    Hammers mated to strings etc etc. 
    Juiced around staples first (5:1)
    Listened.
    Applied juice to sides above mouldings Bass 15:1. tenor 10:1, treble 5:1 then over top.
    Lower treble section still somewhat soft, applied a second application.
    Now power has been developed.  Piano sounding crude but  i'm in the ballpark.
    I have not juiced the shoulders at all.
    Now i'm working on smoothness, finding notes i like and altering the neighbors i don't to match.
    Question:
    Some notes are too powerful.  Curious what go to technique others have in this situation. Is the needling technique (in the picture) used by anyone?
    It uses a single needle aiming for the middle of the "triangle" zone from the horizontal. Since the lacquer stiffened that area, wouldn't it make sense that a needle can reduce that.
    Thanks in advance
    -chris


    ------------------------------
    "It is the mark of an educated mind to be able to entertain a thought without accepting it".

    chernobieffpiano.com
    865-986-7720
    ------------------------------


  • 2.  RE: Reducing Power in a Ronsen Hammer question

    Posted 07-16-2018 09:29
    I use Bacons often, the least dense of Ray's felts. The first step is usually 4:1 applied to the point of the molding from the side with the action turned sideways into a vertical position.  I usually do this up to the alto strut. Keep the lacquer near the molding tip, so it doesn't migrate too far towards the perimeter. Sounds like you did this already.

    Even with the Bacon's, I actually do most of my work with needles not lacquer (or B72, which I have been using for a year or so). Some low shoulder needling will transfer some tension up to the near crown, and often develop really nice sustain with that alone. 

    I can't think of a situation where I've juiced the low shoulders actually. If I am lacking power with these hammers, after releasing some tension, as above, I will apply the tiniest surface only amount of juice at the near crown just in back of and sometimes in front of the crown. This is surface only, applied with either a bent pipe cleaner or flux brush...very very minor application. Wait for it to break down and maybe do it a second time a few days later 15:1...go slow.

    I have not used the VFG. Have used Weikerts, low profile Weikerts, and Wurzen...but prefer the Bacon's since Bacon fixed their felting equipment.   

    Re the needle orientation you posted, I have tried various non-standard needle directions, from the side into that area as well. None of these has produced results I was looking for, so mostly don't go there anymore. I have had success with a technique that is usually considered hard hammer specific...that is...needle inserted in the "angel (angle) shot" direction. However, I don't do this as an angel shot in the center of the crown as angel shot does it. Rather using that angle, working up a series of these angled insertions in a line projected from each of the string mark along the distal perimeter of the hammer, working from the mid shoulder up to the near crown.

    Re your reasoning on your drawing, I would say you applied the juice to the top of the molding because it needed some stiffness there. Needling it there would at best just take you full circle to where you started. Instead, now that this area is stiffened, resilience in other parts of the felt, shoulders and near crown is what the board is asking for. 




    ------------------------------
    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 3.  RE: Reducing Power in a Ronsen Hammer question

    Registered Piano Technician
    Posted 07-16-2018 12:05
    So, in agreement with Jim, (assuming I am reading him correctly, and from what I learned at Lancaster this past week repeatedly), I would suggest turning your angle of insertion UP by about 95°-100° and insert NEAR the strike point, but AWAY from the strike point. Penetrate into the shoulders from there. IOW going more WITH (between) the felt layers, rather than ACROSS the felt layers.

    Does this make sense? 

    Pwg

    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 4.  RE: Reducing Power in a Ronsen Hammer question

    Posted 07-16-2018 14:44
    Thanks Jim,
    Was there an article in the journal regarding the angel shot technique? 
    -chris

    ------------------------------
    "It is the mark of an educated mind to be able to entertain a thought without accepting it".

    chernobieffpiano.com
    865-986-7720
    ------------------------------



  • 5.  RE: Reducing Power in a Ronsen Hammer question

    Posted 07-16-2018 19:43
      |   view attached
    I'm sure there was...somewhere.  However, here is the concept. I got this from David Andersen. As I said, its not angle shot voicing, but the angles are similar. The difference between this and angel shot, is that the roughly tangent angle to the hammer's perimeter in angle shot goes in in the middle of crown. David's approach projects the string mark down the perimeter of the hammer, and inserts needles bit by bit up that projected line.

    edit...this attachment is backwards...see attachment in my following post. I will delete this one if I can figure out how.

    ------------------------------
    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------

    Attachment(s)

    pdf
    andersen voicing.pdf   28 KB 1 version


  • 6.  RE: Reducing Power in a Ronsen Hammer question

    Posted 07-16-2018 19:47
      |   view attached
    damn...that's backwards. How does one delete an attachment...the insertions go on the distal perimeter of the hammer...damn.

    ------------------------------
    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------

    Attachment(s)

    pdf
    andersen voicing.pdf   28 KB 1 version


  • 7.  RE: Reducing Power in a Ronsen Hammer question

    Registered Piano Technician
    Posted 07-17-2018 09:57
    Jim,

    Backwards in what way?  This was precisely how he demonstrated it. Just what I was trying to describe.

    Pwg

    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 8.  RE: Reducing Power in a Ronsen Hammer question

    Registered Piano Technician
    Posted 07-17-2018 11:32
    Hammer voicing techniques need to be planned with the full understanding of the relationship between the frequency of the strings and the hammer weight. When one gets into the upper 50's of the compass, (just above C above middle C), reducing hammer weight must be done first before juicing.

    I never need juice below that range in properly shaped Ronsen Hammers.

    It is important to know that treble hammers do not need the wide range of felt spring rates than that of the lower treble, tenor and bass hammers.

    When you juice you must keep in mind how difficult it is to get the hardener into the felt. It is very easy for the hardener to "pile" up in the surface and produce an ugly tone.

    So I find it best to use quite dilute lacquer in acetone and apply right to the strike/upper half of the hammer. Don't apply it to the shoulders. Once it dries if the tone is too bright, re-wet with acetone the strike surface and squeeze/blot some lacquer with a paper towel off/out of the hammer then follow with a total rinse of the lacquer with acetone down into the shoulders.

    If the tone is still too dull; re-wet the surface with acetone, let it soften the hardeners already in the felt for about 5 minutes and then apply more hardener just like you did before.

    Repeat above steps as needed giving adequate time for things to dry.

    Then in the future should work-hardening of the hammers from playing produce too much brilliance, use the re-wet, wait and rinse with thinner process combined with squeeze/blot of the striking surface.

    ------------------------------
    Edward McMorrow
    Edmonds WA
    425-299-3431
    ------------------------------



  • 9.  RE: Reducing Power in a Ronsen Hammer question

    Posted 07-17-2018 14:13
    I posted a pdf that was backwards and couldn't delete it. The second pdf is correct, as you noted.

    ------------------------------
    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------



  • 10.  RE: Reducing Power in a Ronsen Hammer question

    Registered Piano Technician
    Posted 07-17-2018 12:29

    If I were ranking Ronsen hammers in terms of firmness I would rate them in this order from softer to harder:

    • Bacon
    • Weickert
    • Wurzen
    • VFG

    How the hammers present in terms of tonal spectrum will depend on other factors, for example, hammer profile (how thick is the felt), crown shape, amount of filing, etc..  Profile is probably the most important factor (along with mass).  A relatively soft Bacon felt hammer can produce a nice spectrum of high partials if the hammer is quite trim and a VFG hammer can produce a somewhat dull spectrum if the hammer is quite bulky.  Treble sections are quite sensitive to excessive mass and/or excessive thickness of felt as the partials that we don't want damped already have a period quite close in length to the string contact time.  Excessive mass, strike point width or felt compression during impact will damp those partials and the tone will be left wanting. Finding a good starting point is important so that the least amount of manipulation is necessary.  One thing you can do is swap hammers from higher sections to see if a less bulky hammer doesn't achieve what you want before you add lacquer.  If it does then consider a healthy filing first. 

    Varying approaches to what to do with the shoulders on these types of hammers I find curious given the contrary approaches.  Some techs advocate a very strong solution in the lower shoulder, others prefer a needling of the lower shoulder.  Since I believe the goals are often similar it makes me wonder whether the approaches are driven by and personal bias and verified more be a placebo effect than anything else. 

    The function of the low shoulder is to support the compression of the top of the hammer on impact.  As the top of the hammer compresses the low shoulder offers both some countering which aids in the hammer restoring itself to its precompression shape.  If the shoulder is too firm and has no give then the compression of the upper part of the hammer is restricted, i.e, the hammer spring is effectively too stiff, too much energy is delivered to the soundboard via the string and we get something too percussive or harsh (short version).  If the shoulder is too soft…well, can it be too soft?  It's a good question.  I'm not convinced that the hammer shoulder can be too soft unless the overall hammer is too soft.  If it is the hammer absorbs too much energy, increases it's contact time with the string and the tone is lacking power and partial development.  

    Since hammers come out of the box fairly consistent in terms of stiffness, it is unlikely that the shoulder will be extremely soft while the area around the crown will be too hard unless it's made that way in the pressing using heat.  More likely if the hammer is too soft then the entire hammer is too soft and needs to be hardened, or stiffened.  That being said, the crown of the hammer will always be stiffer than the shoulders because of the pressing process which wraps the felt around the molding giving the most stretching and  compression to the crown and the least to the shoulder.  That is as it should be. 

    If the entire hammer is too soft, the best approach, then, is to simply saturate the hammer with the required solution to stiffen the entire hammer.   It's unlikely that you will stiffen the shoulder too much.  For that purpose I've written about the solutions and types of lacquer that I prefer, one which remains flexible.  Pianotech sells that type of lacquer and there's some discussion that the lacquer that Steinway uses for dipping is also this type of "soft setting" lacquer that remains somewhat rubbery after it cures. 

    Applications should simply be over the top of the hammer or in from the shoulder as you prefer but a uniform amount which saturates the entire hammer to the core.  I have done the apply lacquer from the side method and did advocate it at one time but in the end trying to control the wicking effect I think is a waste of effort and a strain on the back to tilt that action onto it's side. 

    Solution strengths, ideally, might vary in different sections with the weaker solutions being applied in the bass and the stronger ones in the high treble. 

    Once the lacquer has cured and you find some unevenness the focus of voicing should be on the upper part of the hammers.  See illustrations below.

     

     

     

    Phase 1 marks the area of needling when the low shoulder is too firm.  This doesn't really apply to Ronsen hammers as the low shoulder simply isn't too firm.  As I mentioned, the fact that some techs choose to actually beef this area up with strong solutions of lacquer and some techs offer that this area needs to be opened up on these hammers suggests at best some disagreement, at worst some confusion.  I think best to just leave it alone.  Renner and other hammers are another story and will need this area addressed to offer more give for the upper part of the hammer and a release of tension over the crown to open up the spring (see above illustration)  (Note:  I prefer this inverted triangle as the "avoid" place, though there are times when needling in this area can't be avoided. That shouldn't be the case with Ronsen hammers unless they are over lacquered).

     

    Phase 2 is where it is likely that Chris should start to address the aggressive VFG hammers.  Play and test at all levels and work toward the crown.  I often turn the three-needle voicing tool so that the needles run parallel to the string line when working near the crown. 

     

    Phase 3 works nearer the crown with the needles pointed slightly away from the strike point.  Again, here I work with the voicing tool turned so that the needles are in line with the string line.  This is for delicate refinement

     

     

     

     

     

    A comment on so called "Angel Shot" voicing.  My own personal opinion is that this is effective but should be limited in use.  The original procedure was a "through the string" procedure with a single needle so in the picture below the keyboard is to the right.  It works because it softens the area very near, or on, the crown, widens the strike point as the needle will expand the felt near the strike point putting softer felt that is just off the actual strike point in contact with the string and damping some upper partials.  It also allows the felt over the crown to release some.  The problem with this method, if used in it's original concept, is that it always needles just one side of the hammer.  If you do this repeatedly it will swell the distal side of the hammer and create a hammer which is somewhat lopsided in shape.  One time to make a quick change fine, but I would argue against repeated use or this or as a method for addressing the entire set.  Some balance between front and back of the hammer should be the routine. 

     

     

     

    Final refinements are done with direct crown voicing, una corda, etc. 

     

     

    To wrap up, the situation with VFG is that even though the hammers have been lacquered I would address the issues with Phase 2, 3 and final phase.  I would ignore any shoulder needling (though if it makes you feel better the placebo effect is real).  I would make sure in lacquering that a uniform application that penetrates fully has been applied with slightly stronger solutions toward the treble.  Second and third applications, except in the very top notes, are rarely advisable but if you've applied the initial application poorly or too weak a solution you often don't have much choice.  Lacquer changes the response characteristics of the felt especially on the backside of the hysteresis loop so if some hammers have more or less lacquer than others they will have a different timbre and no amount of needling will resolve that completely. 

     

    Good luck

    (Sorry, no time to proof for typos)

    Note: illustrations are taken from a book I'm in process of writing so are subject to copyright. 

    David Love

     



    ------------------------------
    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    ------------------------------



  • 11.  RE: Reducing Power in a Ronsen Hammer question

    Registered Piano Technician
    Posted 07-17-2018 16:49
    Mr. Love,
    while I disagree with some of what you've written here,please put me on the list of pre-release orders for your book.

    ------------------------------
    Karl Roeder
    Pompano Beach FL
    ------------------------------



  • 12.  RE: Reducing Power in a Ronsen Hammer question

    Registered Piano Technician
    Posted 07-17-2018 18:33
    Well, extended article is probably more accurate. When (and if) it's publishable it'll be free.

    ------------------------------
    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    ------------------------------



  • 13.  RE: Reducing Power in a Ronsen Hammer question

    Posted 07-17-2018 17:14
    David,
    Thank you for chiming in. And thank you for the description and diagrams which are very useful in trying to understand the concepts of other individuals trying to share knowledge.  I've been working with Ronsens now for close to 20 years, plus i have read everything you wrote on voicing that i could find going back a couple decades.

    My diagram above was a question i had based on my understanding (or misunderstanding) of a description you  gave a few years back.
    Here's the quote regarding how to reduce power:

    "Moving up through the dynamic range your next target is deeper in the hammer, say 4-6 mm under the crown. Play at mp and check for uniformity again.  In this case you are working with a longer single needle (about 10 – 12 mm).  The insertion takes place off the strike point by about 5 mm and the insertion is from the front of the hammer at a slight downward angle just off horizontal.  You don't need to insert all the way through the top of the hammer initially.  Start by inserting just beyond half way to just reach beyond the center line of the hammer.
     At mp if a hammer is louder than its neighbors the hammer is not compressing much and so the target area is not that much below the surface of the hammer.  If your initial half way plus insertion doesn't do it then slide the action out and insert from the other side at the reverse angle or raise the insertion point a bit higher as you may be too deep and not addressing the area to which the hammer is being compressed.  Experience will need to be your guide.  Check hammer mating."

    My point is that the new diagrams make your concepts much more clear. I'm still not sure of what technique you were  describing in the quote though.

    I believe a simple test for lacquer is to put a drop on glass and let it dry, then check it's flexibility. I'll have to try that myself when i have time as i just use whats handy in the shop. Mohawk Piano lacquer most of the time. It has a 18.75% solids content. I also have the wurdack, and I have some duplicolor lacquer that i used for spraying metal. It's very absorbative by observation.
    -chris


    ------------------------------
    "It is the mark of an educated mind to be able to entertain a thought without accepting it".

    chernobieffpiano.com
    865-986-7720
    ------------------------------



  • 14.  RE: Reducing Power in a Ronsen Hammer question

    Registered Piano Technician
    Posted 07-17-2018 18:36
    I should add I often start with light, final phase sugar coating. It can help avoid confusion about which part of the hammer is too hard and help with una corda voicing later.

    ------------------------------
    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    ------------------------------



  • 15.  RE: Reducing Power in a Ronsen Hammer question

    Registered Piano Technician
    Posted 07-18-2018 15:21
    As in a light wire brushing of the crown to temporarily even things out?

    Pwg

    ------------------------------
    Peter Grey
    Stratham NH
    603-686-2395
    pianodoctor57@gmail.com
    ------------------------------



  • 16.  RE: Reducing Power in a Ronsen Hammer question

    Registered Piano Technician
    Posted 07-18-2018 18:03
    No, as in shallow needling as illustrated.

    ------------------------------
    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    ------------------------------



  • 17.  RE: Reducing Power in a Ronsen Hammer question

    Posted 07-18-2018 15:34
    So here is a short list of techniques i used on these VFG Ronsens that work very very well. In no particular order.

    • Most important is mating strings to hammer. Many times. 
    • Listening then knowing  what technique is appropriate. It just takes experience.
    • In the Alto and Soprano sections there was a popping flutie sound. It's a sound caused when there is too much felt. Sanding off a couple of layers did wonders. Important to know that sound as it is frequent with Ronsens.
    • The unichords responded well to a 15:1 when they are muddy and weak.
    • The top six notes needed more felt removed and another 10:1.
    • When pp was too soft, i pound the top with my brass hammer.
    • And some sugar coating to remove pings.
    • finished off with 600 and 1,000 grit.

    Here's a technique that works magic on Ronsens. I use a single needle (.050) about 3/8 long,  and in my mind i think of it as a probe. When a note sounds thin, stick it in at 3:00 on the proximal side. If the felt is soft, then just the one stich and listen to the note. It will most likely sound fuller. If the felt is hard then go to 2:00 and stich again and listen. So if soft one stich, if hard 2 stiches.  All the stiches are in the "cup" line, This really opens the tone. And more importantly you get a feel of the hammer.

    First time i used the VFG's. I would use them again because they are very user friendly, sound awesome, and they are cheaper than the other Ronsens at $250. I think the other Ronsen are $400 now.
    -chris

    ------------------------------
    "It is the mark of an educated mind to be able to entertain a thought without accepting it".

    chernobieffpiano.com
    865-986-7720
    ------------------------------



  • 18.  RE: Reducing Power in a Ronsen Hammer question

    Registered Piano Technician
    Posted 07-18-2018 18:08
    Yes it is presumed that prevoicing procedures are fully employed (especially hammer string mating) before resorting to any needling or lacquer. Otherwise you're stabbing in the dark. After any crown or near crown needling that mating should be checked again, and again.

    ------------------------------
    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
    ------------------------------



  • 19.  RE: Reducing Power in a Ronsen Hammer question

    Posted 07-25-2018 13:19
    A little follow up here, since there never was really an answer..
    Everything David said for the most part came true. But one important thing was left out. It's not always the hammer.
    First, the angel shot did work, but it is limited in effectiveness, and can easily become destructive. So as David said, it should be of limited use.
    Next, the Irwin technique of juicing the staple if done at the beginning can in the end work against you. In my case, I had to go back and deep needle the shoulders because the mf and ff blows created distortions. I would prefer not to have to go back and needle if i can help it.
    Last but not least, reducing the volume of a particular hammer. I had a situation were NO technique reduced the power. I finally switched hammers and it turns out that no matter what hammer was on that note it would pierce my brain. So what i ended up having to do that WORKED, like a charm, was install 3 riblets in the "alto section" of the soundboard. That did it.
    Nothing like trying to fix a hammer problem when its not a hammer problem.

    BTW, i have recordings of the "before the rebuild", after the rebuild (prior deep needling), and now after deep needling. Listening to the 3 recording back to back is quite instructive. All three should be on my website by next week.

    One more lesson i learned, i am never rebuilding again without a key pounding machine, for some reason this particular piano (Lester Grand) fought me every step of the way. Not a  100% and still needs to be played in a while. Wish i had more time, Hate that. I'm making my own key pounder out of a recycled tread mill. Great variable motor, just drew up the plans. Most likely only cost $200 to make. Probably make a video of the too.
    Take care,

    -chris

    ------------------------------
    "It is the mark of an educated mind to be able to entertain a thought without accepting it".

    chernobieffpiano.com
    865-986-7720
    ------------------------------



  • 20.  RE: Reducing Power in a Ronsen Hammer question

    Posted 07-25-2018 16:30
    <So what i ended up having to do that WORKED, like a charm, was install 3 riblets in the "alto section" of the soundboard. That did it.
    Nothing like trying to fix a hammer problem when its not a hammer problem.

    Bingo!   Three cheers for honesty!

    You were chasing a board resonance, and no hammer trick will fix this. That's why I feel one of the rebuilder's essential tone regulating skills is first, to know that resonances will populate any board of any provenance, and second, to know what, if anything, can be done to shift the nasty resonance. I say shift, because at least in my experience of regulating the sound of the board itself, mass loading, or adding riblets or in my case sometimes longer auxillary ribs, will shift the resonances, but they will not make it/them go away. Shifting the resonance will often slightly compromise a larger band of notes less aggressively than the situation where there is such an impedance match that only one note is honking to beat the band. Sometimes shifting an entire section will change the color of the area enough to redefine resonant area so its somewhat mitigated...but it does not go away entirely. 

    I hear these areas on every piano of every provenance and price range, including high end items. Knowing what you are dealing with changes the whole calculus of "voicing" hammers. Its very interesting how you can voice a piano by not touching the hammers, but messing with board structure. The education is striking in being able to see the changes in real time, without touching hammers. 

    If I didn't know better, I would have been tempted to say this was a "too flexible" board issue in the problem area...Ron harped on this without respite. However, at this point I disagree with him. I have experimented  and continue to experiment with these problematic and annoying resonances ad nauseum. I can report stiffer or more flexible boards not withstanding, resonances will be present...the various impedances boards present, will just locate the resonant mode in different parts of the compass.

    Excellent post Chris! This is never discussed in "voicing" discussions, and should be understood as one of the primary gremlins voicing hammers tries, unsuccesfully, to address.

    ------------------------------
    Jim Ialeggio
    grandpianosolutions.com
    Shirley, MA
    978 425-9026
    ------------------------------