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Foam baffles

  • 1.  Foam baffles

    Registered Piano Technician
    Posted 06-06-2021 16:09
    I'm going to help a customer install foam baffles (bottom side) for a piano and want to know if anyone has made them themselves, what foam did you use (I want at least 4" foam for this) and what did you use to cut it and how did you go about creating the templates.  I don't think any of the previous suppliers are doing these anymore but if they are let me know who's making them.  

    Thanks


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    David Love RPT
    www.davidlovepianos.com
    davidlovepianos@comcast.net
    415 407 8320
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  • 2.  RE: Foam baffles

    Registered Piano Technician
    Posted 06-06-2021 17:29
    I made a paper pattern and cut it 1" wider with electric carving knife.

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    Larry Messerly, RPT
    Bringing Harmony to Homes
    www.lacrossepianotuning.com
    ljmesserly@gmail.com
    928-899-7292
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    Original Message


  • 3.  RE: Foam baffles

    Registered Piano Technician
    Posted 06-06-2021 23:10
    Thanks Larry. Was the electric knife effective in cutting it easily?  What product did you purchase and how much square footage did you need to have enough material?

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


  • 4.  RE: Foam baffles

    Registered Piano Technician
    Posted 06-07-2021 06:42
    The knife was effective. Got the foam at an upholstery supply outlet. Don't remember how much but with friction fit a cavity can have more than one piece inserted side by side

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    Larry Messerly, RPT
    Bringing Harmony to Homes
    www.lacrossepianotuning.com
    ljmesserly@gmail.com
    928-899-7292
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    Original Message


  • 5.  RE: Foam baffles

    Registered Piano Technician
    Posted 06-07-2021 00:48
    I've done this in the past. I would think 4" thick will be overkill unless you want it sounding really dead. 1 1/2" is a lot, 2" will kill fairly effectively. 

    I didn't need an inch over width, but your mileage may vary. I will second the electric carving knife.

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    David Stocker, RPT
    PNWRVP
    Olympia WA
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    Original Message


  • 6.  RE: Foam baffles

    Registered Piano Technician
    Posted 06-07-2021 02:02
    Any long thin and sharp knife will cut foam.

    Please let us know how effective your project was!

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    Blaine Hebert
    Duarte CA
    626-795-5170
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    Original Message


  • 7.  RE: Foam baffles

    Registered Piano Technician
    Posted 06-07-2021 08:56
    Hi David,

    I have used this product and have been very happy with it:

    https://www.markertek.com/product/mf-4/markerfoam-54x54-ul94-sound-absorption-acoustic-foam-panels-3-inch-gray

    In my opinion the only way to cut it is with an electric carving knife.  

    David

    David Weiss
    Registered Piano Technician
    (434) 823-9733
    davidweisspiano@gmail.com
    www.davidweisspiano.com

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    David Weiss
    Charlottesville VA
    434-823-9733
    davidweisspiano@gmail.com
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    Original Message


  • 8.  RE: Foam baffles

    Registered Piano Technician
    Posted 06-07-2021 10:35
    I have also used this very product. Real acoustic foam is designed for the purpose, whereas cushion foam is not. Actually, for reduction in sound, they don't work that well. I'd say at most 20 %. If you want to stop sound, you need to seal the area and use mass-loaded vinyl. Acoustic foam is meant to absorb some sound reflections only, not for soundproofing.
    Paul McCloud
    San Diego


    Original Message


  • 9.  RE: Foam baffles

    Registered Piano Technician
    Posted 06-08-2021 23:26
    I think 20% would be fine in this case although I'm curious what product you would use in this case to increase damping.  

    Those who use the electric knife to cut this stuff, how well does that work?

    thanks for the input all.

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


  • 10.  RE: Foam baffles

    Registered Piano Technician
    Posted 06-09-2021 00:00
    Hi David:
    Electric knives are the best way to cut this stuff. You might find one in a thrift store.
    Sound absorbing can be done with acoustic foam ($$$) or Rock Wool (ROXUL) or fiberglass panels. These have to be wrapped with some kind of material to keep the material from shedding. Look up DIY acoustic panels for use in recording studios. Thicker the better. But they don't absorb very much because they are light and lots of sound passes through. Soundproofing auto interiors on custom car installations use mass-loaded vinyl sheets to deaden most of the sound coming from the undercarriage of the car. It's heavy, and must be that way to block the sound. Maybe overkill in this situation, but if you want to reduce the sound level more than just a little, it works very well.
    It may also work to push foam up against the soundboard.
    I had a client once who laid a piece of felt directly on the speaking string area. Worked surprisingly well.
    Paul McCloud
    San Diego


    David Love:

    I think 20% would be fine in this case although I'm curious what product you would use in this case to increase damping.

    Those who use the electric knife to cut this stuff, how well does that work?

    thanks for the input all.

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


  • 11.  RE: Foam baffles

    Registered Piano Technician
    Posted 06-09-2021 00:26
    Thanks Paul

    Any idea as to approximate square footage you need to cut all these sections?  

    D

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


  • 12.  RE: Foam baffles

    Registered Piano Technician
    Posted 06-09-2021 01:01
    Hi David:
    I purchased this stuff many years ago, and I don't remember what the size was. I imagine two or three 2 X 4' sheets would suffice, obviously depending upon the piano size. I was doing small baby grands where the client had a player system installed and wanted to damp down the volume. Honest, I can only guess how much you'd need.
    Here's a company that markets acoustic foam, pretty cheap:
    https://www.thefoamfactory.com/acousticfoam/acousticfoam.html. Not quite as good as Auralex, but almost. With Auralex, you're paying mostly for the name.

    Best,
    Paul


    David Love

    Thanks Paul

    Any idea as to approximate square footage you need to cut all these sections?

    D

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



    Original Message


  • 13.  RE: Foam baffles

    Member
    Posted 06-07-2021 10:29
    you can make a pattern by tracing the lid as you would if you needed to have a string cover made. Use that paper pattern and tack it under the piano after you cut off the large piece the keybed and trap works use. then outline all of the openings between the beams. use a long nosed pattern mark from www.fastcap.com to mark your foam baffles and cut away with a carving knife . Certain types of shears can be used to cut foam but regular scissors are likely to fail.

    I am making custom foam inserts for all of the tools I store in tool cabinet drawers. I bought the pen and some other tools from either Woodcraft or Rockler. Both places are worth checking out

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    James Kelly
    Owner- Fur Elise Piano Service
    Pawleys Island SC
    843-325-4357
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    Original Message