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Damper guide bushings, & Lubricants

  • 1.  Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 08-31-2015 18:28

    Starting  a new thread from the ticking/clicking thread:

    I thought this might be a good opportunity (hopefully) for us to bring out some further clarity regarding damper guide issues and the related topic of good uses for particular lubes. Also, Fred does ask a good question about centering or leaning. It is my understanding that the "leaning technique" is in the Steinway manual, correct? 

    Using Protek CLP in a hypo-oiler (enough for it to run down the wire, but NOT getting wild/crazy with it) CAN sometimes get you through a very slightly sluggish/sticking damper situation in which the concert is about to start, etc, --- HOWEVER, I do not consider this a proper repair or "fix". Must follow up by re-sizing, etc.

    I personally have never used "Pro lube" for this, nor would I probably ever try this-myself. So one of my main questions is: could using ProLube on a damper wire actually be what is at question here? (possibly causing issues or clicks?)

    I COMPLETELY agree that applying McLube 444 Dry film lube to Damper guide wires is excellent (I much prefer the dobber in the small bottle-Schaff! Refill with quart size from Pianotek)  Much easier to use and works EXTREMELY well on front rail bushings, and bal. rail also. Very quick and easy. NEVER allow this stuff on a KEY BUSHING!! IT RUINS THEM IMMEDIATELY! -Dont' ask me how I know!--)

    Regarding sizing the bushings: I tend to use the heated broach method using the proper size bridge pin for most sticking damper issues. However, my favorite method, especially when replacing a set, is using a sizing solution--either about 50/50 water to denatured alcohol. I have experimented with VS Pro felt as a sizing solution and to provide some long-term lubrication. It's definitely great for Front rail bushings- again, as a sizing solution and to help them last. NOT as a cure for worn out bushings. (an ENTIRELY different topic!) 

    So, I am having a hard time understanding why there seems to be some reservation among the "greats" about using this. So I would like some input as to whether some of you have had some real-life issues using this product, and would like to hear some reasons why it is not more accepted. 

    Thanks much to all! Kevin

    __________________________

    Mark,

    Just to clarify, Protek makes Protek CLP and ProLube. So are you distinguishing between the two, but calling "ProLube" "Protek?" [CLP being intended for felt, ProLube for metal]

    Since the noise is on key release, it seems it had to be a hardness of the felt surface, no? Difficult to imagine either product (applied to the felt) causing that symptom. How do you set up your damper wires vis a vis the bushings, centered or leaning?


    ------------------------------
    Fred Sturm
    University of New Mexico

     



  • 2.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 08-31-2015 21:30

    Thanks Fred, I had to check.

    ProLube is what we originally applied to damper wires in field service, working it into the bushings via the wires by pedaling. In the shop, where we prefer to McLube the wires (removed from guide-rail), we would use a syringe and saturate the cloth bushings with CLP. However, I've also used ProLube in a syringe to saturate the bushings.

    And yes, hard to imagine either of these products causing a tick. What I imagined is that excess product may have pooled, or left a skin, or some surface different than raw felt-cloth in contact with the wire. However, I didn't find anything on the cloth. And the sound itself was so subtle, almost non-evident, that it was very hard to categorize.

    The wires in this piano are aligned for gentle contact with the cloth bushing through the entire range of motion - though hopefully not leaning. However that could have more to do with how my head was tilted at the time.

    I experimented with side-pressure on the wire to prove that contact with the cloth was the source. Then finally pressed the bushing out completely, so that the only material missing from the chain of parts was the cloth itself - and the issue was gone. 

    Again, I'm not faulting the products, just suspicious that something in my application may have left surplus material - enough to be heard only in the most delicate passages.

    That's all I've got. Meanwhile I'm good with leaving the bushing cloth untreated, and McLubing the wires.

    Best!

    Mark


    ------------------------------
    Mark Cramer
    Brandon MB
    204-727-2350
    ------------------------------

    Mark,

    Just to clarify, Protek makes Protek CLP and ProLube. So are you distinguishing between the two, but calling "ProLube" "Protek?" [CLP being intended for felt, ProLube for metal]

    Since the noise is on key release, it seems it had to be a hardness of the felt surface, no? Difficult to imagine either product (applied to the felt) causing that symptom. How do you set up your damper wires vis a vis the bushings, centered or leaning?


    ------------------------------
    Fred Sturm
    University of New Mexico



  • 3.  RE: Damper guide bushings, & Lubricants

    Posted 09-01-2015 11:58

    The VS Profelt works beautifully on sizing any bushing in particular key bushings (except in the case that they are extremely worn) and damper guide rail bushings. The trick is to use a heated broach which cures the felt better and sizes to the right diameter.

    ------------------------------
    Andrew Saderman
    Forest Hills NY
    718-263-6508
    ------------------------------




  • 4.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-01-2015 12:45

    I use the Steinway method, of having the damper wire bear against one side of the bushing. There are several functional advantages to this, but the major one is that the wire doesn't chatter. With any system in which the wire is intended to rise in the middle of a felt bushing, there is bound to be a degree of chatter if the bushings are eased enough for the wire to be "completely free" - and it must be very close to completely free to function well. With the system where the wire is centered, tolerances are tight enough that humidity changes will cycle between sluggishness and slop. Not much of an issue with the side-bearing method, as we are only talking about the swelling and shrinking of the portion of the felt between the wood and the wire, and the effect it has on the friction.

    The trick is to control the degree of bearing very closely: you must have a very light and controlled touch on the wire bending tool, and gauge the degree of lean quite precisely. This is not so hard once you have done a couple sets, and judgment is a matter of pushing the wire away from the bushing and feeling the pressure to return to it, with a light finger below the guide rail. Other advantages include a much more controlled rise of all the dampers in parallel, not fore/aft jogging, side to side wobble. But the main thing is better damping. Because the damper head is bearing against a surface with a spring (the wire serving as a spring), it is more stable when it is reacting to the vibration of the wire - when it comes down to damp a string. 

    I don't know how many of you have seen Stephen Birkett's super slow motion video of a grand damper head on bass strings (I think it was really intended to show the vibration of the wire). The damper head first of all is wildly flailing around when the key is held down. When the key is released and the damper hits the strings, it bounces all over the place in random ways before finally settling. Obviously this is having an impact on damping.

    Coming around to the topic of lubricants, in this style of setting up a damper system, it is quite important to lubricate the bushings or wires or both. I think that this system would pretty much insure against any click of the wire against the bushing. I lubricate the wires above the guiderail, pedal down, running a brush along the wires, using Protek CLP. Have never had a problem (but that's not to say I would guarantee there could never be one - might not have got into a finicky enough situation).

    ------------------------------
    Fred Sturm
    University of New Mexico
    fssturm@unm.edu
    http://fredsturm.net
    http://www.artoftuning.com
    "We either make ourselves happy or miserable. The amount of work is the same." - Carlos Casteneda
    ------------------------------




  • 5.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-01-2015 13:27

    Wow- excellent post Fred. This makes complete sense and does not contradict any other goal or "rules of thumb" of any other quality method--as long as there is just the right amount of "leaning" which you have THOROUGHLY clarified! Thanks much!

    I still believe that the Mclube 444 is superior for lubing these wires IF removing the dampers,  but it's pretty much a moot point, as the main thing is to use a good quality lube and "Protek CLP" is EXCELLENT and a great product to have handy for many other piano uses as well. 

    Best! Kevin

    ------------------------------
    Kevin Fortenberry
    Registered Piano Technician
    Lubbock TX
    806-778-3962
    ------------------------------




  • 6.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 18:39

    Fred said: I use the Steinway method, of having the damper wire bear against one side of the bushing....The trick is to control the degree of bearing very closely:

    Several years ago I heard that Steinway had actually developed a specification for the amount of bearing that the wire exerts on the one side of the bushing.  In other words using a gram gauge you can measure how many grams it takes to start to move the wire away from the bushing and then make adjustments to get the proper measurement.  I don't know if Steinway ever did come up with a spec and if so, what that spec is.  Does anyone know?  I guess I should check with Steinway. 

    I have worked on new Steinways that develop damping problems because the wire can get slightly "mis-bent" in shipment creating a change in the wire to bushing pressure. Then when the humidity changes the dampers start to hang up.  That's where attention to the pressure bends can correct the problem fairly quickly.  But as Fred points out, it takes a deft touch with the wire benders. Perhaps one also needs a gram gauge to be sure the pressure is correct and even from wire to wire.

    Richard West
    Oro Valley AZ
    520-395-0916
    440richard@gmail.com
    ------------------------------




  • 7.  RE: Damper guide bushings, & Lubricants

    Posted 09-02-2015 20:24
    Miss-bent in shipment, huh? Yea, that must be it.
    Ron N




  • 8.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 20:31
    Well, Okay.  That's what I was told.

    rw





  • 9.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 21:02

    Why Ron, it HAD to have happened during shipping--or it could be post shipping gremlins--because it was perfect when it left the factory, right?

    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------




  • 10.  RE: Damper guide bushings, & Lubricants

    Posted 09-02-2015 21:12
    Of course. It's a mystery.
    Ron N




  • 11.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 10:06

    I size the bushings using a #7 bridge pin and alcohol. First finish the guide rail with shellac and lightly swab the holes. After installing the bushing cloth insert a #7 bridge pin then saturate the bushing with alcohol. The alcohol will size the bushing around the bridge pin as well as reactivate the shellac which will create a light bond with cloth to the guiderail. I find this method more stable than heat sizing.

    I've never had a damper wire "click" against s new bushing. If there's a click it's more likely the wire loose in the damper head. Secure that with a drop or two of thin CA glue if necessary.

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




  • 12.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 10:44

    BTW you can also use the alcohol sizing method on key bushings.  Once the glue is dry and with the caul still in place apply alcohol to the bushing and replace the caul (you may have to raise the caul slightly to do this) until dry.  It won't damage the integrity of the glue joint and it will size it to the caul perfectly.  

    I use Protek CPL (center pin lubricant) for lubricating damper wires.  On installation, since the wires have been polished (hopefully) you just want something to clean and protect them which the CPL does nicely.  I apply a drop to the wire before I insert it when I'm installing dampers or if the dampers are already installed just move the damper head slightly to give access to the top of the wire and put a couple of drops at the top and let the run down to the bushing.  I don't like spraying the McClube mold release stuff.  I will destroy bushings if you spray it on them and it's nasty and adds a coating of some type which I don't care for.  I do use it on plate flanges for pinblock mating with epoxy--it is a mold release product after all.

    For key pins Protek CPL also works well as does TFL 50 which then transfers to the bushing cloth and  tends to keep things free. With the keys off the frame you can lightly spray with TFL-50.  If the keys are in the frame you can tip the action on the back rail (grand) and apply Protek with a few drops on the key pins directly as will as a drop on top of the balance rail pin.  That's enough usually.   


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




  • 13.  RE: Damper guide bushings, & Lubricants

    Posted 09-02-2015 11:53
    McLube has a number of formulations, the stuff it leaves on the surface
    is molybdenum disulfide and a teflon based mix. That's the mold release.
    The rest is just the delivery system for it. I used to use it, but
    haven't for many years.
    Ron N




  • 14.  RE: Damper guide bushings, & Lubricants

    Posted 09-02-2015 12:29
    A correction. The McLube 1708 Pianotek sells is indeed intended as a
    lubricant. We used to get McLube from Player Piano Company in the early
    1980s which was a mold release, and had some issues as a lubricant.
    Badly outdated information strikes again. My apologies.
    Ron N




  • 15.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 12:29

    I stay away from spray application of any lubricant. In the first place, I don't want to put propellant and vehicle (solvent) into the air, but the main thing is that I want to control where the material goes. For McLube 444, I just use a pipe cleaner, bend the end back on itself (about 3/4"). For things like key pins, the bend straddles the pin, and puts it right where I want it, takes less than 10 minutes for the whole set, probably less than five (haven't timed it). The bent pipe cleaner can be used flat to paint McLube on things like capstans, glide bolts, front bottom edge of keyframes, side of frame where it bears on the return spring, etc. 

    This method minimizes the amount of material used, which minimizes any environmental hazards. McLube 444 sticks pretty well to metal and remains a very slick surface for wood, without attracting dirt, glazing, etc. I think a lot of people have found problems because of spraying, and having it get into felt that should remain supple (like key bushings). Yes, it will harden felt, it dries hard. Dry some in a bottle cap and find out what is left: a white substance much like what is used by Steinway for impregnating action centers.

    Protek CLP (I think the acronym is CleanLubricatePenetrate) or ProLube don't dry, or at least it takes a very long time. (I do remember the spout on my valve spout oiler I use exclusively for CLP becoming clogged, and in cleaning it out I found bits of solid similar to dried McLube. But this was after years).

    ------------------------------
    Fred Sturm
    University of New Mexico
    fssturm@unm.edu
    http://fredsturm.net
    http://www.artoftuning.com
    "We either make ourselves happy or miserable. The amount of work is the same." - Carlos Casteneda
    ------------------------------




  • 16.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 13:52

    Fred, I could not agree more with this post. Although I mentioned the "dobber" that come in the small Schaff bottle of McLube 444, a pipe cleaner sounds MUCH more accurate. This dry-film lubricant is one that I just can't do without anymore. 

    Kevin

    ------------------------------
    Kevin Fortenberry
    Registered Piano Technician
    Lubbock TX
    806-778-3962
    ------------------------------




  • 17.  RE: Damper guide bushings, & Lubricants

    Posted 09-02-2015 14:32
    Hi,

    As a follow up to this and Ron's note, here is the information from the
    MSDS for MacLube-444 (from www.globalspec.com, for which one has to
    register):


    Product Category: Industrial Lubricants
    Type: Solid or Dry Film Lubricant
    Functions: Lubricant; Sealing, Intrusion Barrier, Seal Forming or
    Sealant; Release Agent or Mold Release; Corrosion Inhibiting or Rust
    Preventative
    Properties:
    Specific Gravity: 1.32 specific gravity
    Use Temperature: ? to 550 F (? to 288 C)
    Composition / Chemistry: Synthetic or Semi-synthetic; Fluoropolymer /
    PTFE (e.g., Teflon?); Molybdenum or Metal Sulphide
    Industry Applications: Automotive or Transportation; Process Equipment,
    Tanks, Reactor or Lines

    I'm including the to note Fred's comment re: the leftover "white
    substance" when the product is allowed to dry being "very much like what
    is used by Steinway for impregnating action centers". This is a yes and
    no. What Steinway uses is flake PTFE suspended in toluol (unless
    they've been forced to switch by the EPA), though methanol works nearly
    as well. The difference is that, as Ron noted, the MacLube 444 also
    includes Molybdenum (or Metal) Sulphide.

    A (very) quick check of the above site reveals that this combination of
    PTFE and Molybdenum Sulphide are present in most (not all) McLube
    products, without regard to application method. What varies are
    (mostly) the carriers/media in which the lubricant, itself, is suspended.

    Kind regards.

    Horace




    On 9/2/2015 10:52 AM, Kevin Fortenberry via Piano Technicians Guild wrote:
    > Please do not forward this message due to Auto Login.
    >
    >
    > Fred, I could not agree more with this post. Although I mentioned the "dobber" that come in the small Schaff bottle of McLube 444, a pipe cleaner sounds MUCH more accurate. This dry-film lubricant is one that I just can't do without anymore.
    >
    >
    > Kevin
    >
    > ------------------------------
    > Kevin Fortenberry
    > Registered Piano Technician
    > Lubbock TX
    > 806-778-3962
    > ------------------------------
    >
    > -------------------------------------------
    > Original Message:
    > Sent: 09-02-2015 12:28
    > From: Fred Sturm
    > Subject: Damper guide bushings, & Lubricants
    >
    >
    >
    >
    > I stay away from spray application of any lubricant. In the first place, I don't want to put propellant and vehicle (solvent) into the air, but the main thing is that I want to control where the material goes. For McLube 444, I just use a pipe cleaner, bend the end back on itself (about 3/4"). For things like key pins, the bend straddles the pin, and puts it right where I want it, takes less than 10 minutes for the whole set, probably less than five (haven't timed it). The bent pipe cleaner can be used flat to paint McLube on things like capstans, glide bolts, front bottom edge of keyframes, side of frame where it bears on the return spring, etc.
    >
    >
    > This method minimizes the amount of material used, which minimizes any environmental hazards. McLube 444 sticks pretty well to metal and remains a very slick surface for wood, without attracting dirt, glazing, etc. I think a lot of people have found problems because of spraying, and having it get into felt that should remain supple (like key bushings). Yes, it will harden felt, it dries hard. Dry some in a bottle cap and find out what is left: a white substance much like what is used by Steinway for impregnating action centers.
    >
    >
    > Protek CLP (I think the acronym is CleanLubricatePenetrate) or ProLube don't dry, or at least it takes a very long time. (I do remember the spout on my valve spout oiler I use exclusively for CLP becoming clogged, and in cleaning it out I found bits of solid similar to dried McLube. But this was after years).
    >
    > ------------------------------
    > Fred Sturm
    > University of New Mexico
    > fssturm@unm.edu
    > http://fredsturm.net
    > http://www.artoftuning.com
    > "We either make ourselves happy or miserable. The amount of work is the same." - Carlos Casteneda
    > ------------------------------
    >
    > -------------------------------------------
    > Original Message:
    > Sent: 09-02-2015 11:52
    > From: Ronald Nossaman
    > Subject: Damper guide bushings, & Lubricants
    >
    > McLube has a number of formulations, the stuff it leaves on the surface
    > is molybdenum disulfide and a teflon based mix. That's the mold release.
    > The rest is just the delivery system for it. I used to use it, but
    > haven't for many years.
    > Ron N
    >
    >
    >
    >
    >
    >
    >
    >
    >
    > Reply to Sender : http://my.ptg.org/eGroups/PostReply/?GroupId=49&SenderKey=744e7873-430c-4005-9334-0adc6db17e74&MID=652944&MDATE=756%253a45%253e457&UserKey=3feecf45-4a69-4cff-bbb2-fd6c7eaf0569&sKey=KeyRemoved
    >
    > Reply to Discussion : http://my.ptg.org/eGroups/PostReply/?GroupId=49&MID=652944&MDATE=756%253a45%253e457&UserKey=3feecf45-4a69-4cff-bbb2-fd6c7eaf0569&sKey=KeyRemoved
    >
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    >
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  • 18.  RE: Damper guide bushings, & Lubricants

    Posted 09-02-2015 16:44

    Getting back to the cloth used for damper guide bushings:

    Where do you get the thick cloth required for some pianos such as the double bushed S&S guide rails?

    I have plenty of 1.8 mm and some 2.0 mm (.071" and .079" respectively) but sometimes even thick er stuff is needed.  Or does everyone double-bush those?

    ------------------------------
    Jurgen Goering
    ------------------------------



  • 19.  RE: Damper guide bushings, & Lubricants

    Posted 09-02-2015 17:23

    Jurgen:

    I've always had a particular dislike for those double bushed guide rails.  Generally I replaced them with "normal" guide rails.  It always seemed easier to me.  Of course I've never been famous for keeping "authenticity" on pianos with bad designs.  One of my many character flaws.

    dp


    ------------------------------
    David Porritt
    Caddo Mills TX
    903-269-3570
    ------------------------------




  • 20.  RE: Damper guide bushings, & Lubricants

    Posted 09-02-2015 17:55
    Likewise. I'd rather make new rails than fight double bushing or super
    thick cloth.
    Ron N




  • 21.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 18:58

    If the damper wire bears on the cloth, it doesn't matter so much how thick the cloth is: IOW you can use a cloth that is not so super thick that it would fill the space of the two layer system.

    I have followed people who used an extra thick cloth - looked like thin action cloth, and was a good bit too thick, so the dampers hung. I simply replaced with my thickest key bushing cloth, adjusted the wires to bear on the side, and no problem. It only becomes a problem if you are trying to fill all the space around the wire, and do so precisely so it will hold the wire firmly but have next to no friction, a tough pair of goals to achieve.

    I guess if I was doing a rebuild, I might replace the whole rail, but in working on a piano that had been rebuilt by someone else, rebushing seems like an easier sell, easier for the customer to stomach. 

    ------------------------------
    Fred Sturm
    University of New Mexico
    fssturm@unm.edu
    http://fredsturm.net
    http://www.artoftuning.com
    "We either make ourselves happy or miserable. The amount of work is the same." - Carlos Casteneda
    ------------------------------




  • 22.  RE: Damper guide bushings, & Lubricants

    Posted 09-02-2015 20:22
    Exactly what I do. I replace when I can, adjust where I can't replace.
    There's infinite anality, and there's survival.
    Ron N




  • 23.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 20:58

    "Anality," my word for the day! Thanks for that, Ron.

    ------------------------------
    Alan Eder, RPT
    Herb Alpert School of Music
    California Institute of the Arts
    Valencia, CA
    661.904.6483
    ------------------------------




  • 24.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-03-2015 11:28

    I use thick cloth.  Not sure where I got it, probably Pianotek.  bought a quarter yard sometime ago and I still have a lot.  I don't find it that difficult to work with.  I don't double bush.  size it the same way as mentioned.  I have no problems with fit or stability.  

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




  • 25.  RE: Damper guide bushings, & Lubricants

    Posted 09-02-2015 11:36
    I install bushings the same way. Very neat and efficient. Never had a
    click from a new bushing. I don't really see how it's possible.
    Ron N




  • 26.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 11:38

    David, this is my favorite method and what I try to use if there is time. This method made me a REAL hero on one occasion many years ago on a brand new Baldwin L that 3 other techs had looked at, etc. I also really prefer the alcohol/water solution and allowing it to dry overnight. Then just a quick polish on the damper wire with 0000 steel wool--apply the lubricate of your choice to the wire, and regulate. I also love that the alcohol re-activates the shellac forming a nice bond to the guide rail--PERFECT!

    QUESTION for all: rubbing alcohol will work, which usually has about 30% water--I have no problem with this, but I tend to use 50/50 water to denatured alcohol. Any strong opinions about this ratio??
    Kevin

    ------------------------------
    Kevin Fortenberry
    Registered Piano Technician
    Lubbock TX
    806-778-3962
    ------------------------------




  • 27.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 09:23

    Well Mr. Fortenberry,

    Since I was doing one last night I thought I'd hold myself up to a little ridicule. I work PTFE powder into the cloth with a small block of hammer felt. I then vacuum the excess off of the cloth and the bench. After installation I size the cloth with VS Prolube and a # 7 bridgepin. The next day I size again with de-natured alcohol. If I'm pressed for time I skip the alcohol.  I prefer to lubricate the cloth and just polish the wires.  My only justification for this is that it keeps away the elephants.  Haven't seen one in the shop in years so it must be working.

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



  • 28.  RE: Damper guide bushings, & Lubricants

    Registered Piano Technician
    Posted 09-02-2015 11:29

    Karl, thanks for your input. I love that you are putting much effort into this! I like the idea of Teflon powder--so you apply it FIRST on the inner side of the felt--very interesting. 

    Now are you saying that you use "VS Pro Felt"??  Because "Prolube" is, again, at different animal altogether!!

    Thanks again, Kevin

    ------------------------------
    Kevin Fortenberry
    Registered Piano Technician
    Lubbock TX
    806-778-3962
    ------------------------------