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Re-veneering front arm curves

  • 1.  Re-veneering front arm curves

    Posted 11-12-2020 15:07
    Anyone have any suggestions on re-veneering the curved front arms of a grand, you know, the part of the arms at the keyboard end, where the veneer is often damaged or completely missing. I have escaped having to do this with veneer, as most of my refinishing, has been black. With black, I just strip the damaged veneer and coat the arm with epoxy. Can't do that on a clear wood finish. I have tried clamping veneer previously with a  custom curved caul, but the adhesion was not good. Its a hard nut to crack I think, otherwise this place would not be such a common site for veneer failure. Any suggestions appreciated.

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


  • 2.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-12-2020 16:13
    Hi Jim-

    I would try traditional hammer veneering using hide glue. It has worked well for me in the past.

    ------------------------------
    David C. Brown RPT
    Garland TX
    tunermandb88.com
    ------------------------------



  • 3.  RE: Re-veneering front arm curves

    Posted 11-12-2020 16:39
    Well, I guess I'm going to learn a new skill. Never done this before.  Any pointers?

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



  • 4.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-12-2020 18:00
    I'll send along some pics of my tools. Really just a veneer saw and a home made hammer. Peter's idea of cross banding is good except you are already applying the face veneer at a 90 degree angle to the groundwork since you are doing it across the rim plies. Couldn't hurt though. Never done it with Titebond. 

    YMMV

    ------------------------------
    David C. Brown RPT
    Garland TX
    tunermandb88.com
    ------------------------------



  • 5.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-14-2020 12:38
    Jim- Here are a few images of my tools. The hammer was made for me by a friend many years ago.The saw is just an off the shelf veneer saw with the kerf/set ground away to a knife edge. I have done much veneering with just these tools. Hide glue brushed on the ground work or cross banding, follow with an iron to liquify the glue and immediately hammer the veneer down. There will be lots of squeeze out and you won't think it will ever clean up but it does. Glue sizing the ground work can help adhesion as does a warm shop but it will usually hammer flat on the first pass. I have done whole lids this way, book matching as I go.A little harrowing the first time but after doing several practice pieces it went pretty smoothly. Including a book cover that show the process a bit.



    ------------------------------
    David C. Brown RPT
    Garland TX
    tunermandb88.com
    ------------------------------



  • 6.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-12-2020 16:40
    Hi Jim,
    Would a vacuum bag be an option for you?

    All the best,
    Jon






  • 7.  RE: Re-veneering front arm curves

    Posted 11-12-2020 17:27
    maybe with west system tape on membrane. Can't get a bag around the whole part. I just read up on hammer veneering...that seems to have a prayer. I think the type of veneer would be key, as they make "flexible veneer now for these kinds of aggressive interior curves.

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



  • 8.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-12-2020 18:03
    My source for veneers-

    https://www.constantines.com/veneer.aspx


    ------------------------------
    David C. Brown RPT
    Garland TX
    tunermandb88.com
    ------------------------------



  • 9.  RE: Re-veneering front arm curves

    Posted 11-13-2020 19:24
    I do 2 layers of cross laminated veneer. Than bend it on violin rim bending iron. 2” pipe with torch inside will work. Than clamp with custom made caul. Caul covered with 1/4” thick foam.

    Alexander Brusilovsky




  • 10.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-12-2020 17:35
    Traditional hammer veneering is a little involved to explain. There are YouTube videos on it though. I have done it numerous times. I have also used the following which I learned from Webb Phillips:

    Use titebond, coating both surfaces with two coats each and allow it to dry, not thoroughly but well beyond the point of tackiness. Then apply using an iron for the flat surfaces, and a heated metal rod stock (at least 3/4" in diameter...bigger is better) for the curved surfaces, the glue will fuse to itself and form an extremely strong bond. Obviously alignment is critical because you only get one shot at it...

    Wear heavy gloves (for obvious reasons). Another thing I would advise is crossbanding. SS never did that (relying on thick veneer) and that is one reason their cheeks fall apart. 

    Pwg

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



  • 11.  RE: Re-veneering front arm curves

    Posted 11-12-2020 20:31
    crossbanding on a curved arm?

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



  • 12.  RE: Re-veneering front arm curves

    Posted 11-12-2020 22:48
    What is the purpose of the cloth mesh that was under the .040" veneer on the arms?  Is that to allow for differential expansion of the vertical plies in the rim. If so, it doesn't work as well as the other laminations in the rim. It seems like there is really no way to assure a long term bond on this area, even if it weren't curved, as there is no way to avoid the differential expansion. Does that make any sense?

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



  • 13.  RE: Re-veneering front arm curves

    Posted 11-12-2020 23:46
      |   view attached
    Hot hide glue, soak the veneer in warm water to make it more pliable before installing with a curved caul. Done it many times.

    I still have the special one-off cauls for the cheeks of an 1889 Chickering. The veneer curved at the bottom of the cheek too.
    I re-veneered the top of the stretcher too, big area...  20 years and still sticking.

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
    ------------------------------



  • 14.  RE: Re-veneering front arm curves

    Member
    Posted 11-13-2020 08:56
    Years ago(1996 NEECSO in Portland, ME),
    Andre Bolduc taught his method using wood glue & an iron.
    You can steam the veneer to the approximate shape.
    Coating both sides with wood glue & allowing it to dry
    creates a "contact cement" type bond when heated.
    To heat the curved surface,
    he made a "rolling pin" out of steel with two wood handles.
    He heated the pin with his wife's iron
    & proceeded to iron the veneer into place.


    --
    John Gallen,
    (860)428-6045 CELL
    Production Supervisor: Brooks, Ltd. Piano Parts, LLC
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  • 15.  RE: Re-veneering front arm curves

    Posted 11-13-2020 09:39
    There is an article in the 2006 Journal that addresses this question.

    ------------------------------
    Floyd Gadd
    Regina SK
    306-502-9103
    ------------------------------



  • 16.  RE: Re-veneering front arm curves

    Posted 11-13-2020 09:40
    Make that February 2006.

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    Floyd Gadd
    Regina SK
    306-502-9103
    ------------------------------



  • 17.  RE: Re-veneering front arm curves

    Posted 11-13-2020 10:01
    The November 2003 Journal features a more detailed article by Webb Phillips that addresses the subject. He describes using hot rollers, as mentioned above.

    ------------------------------
    Floyd Gadd
    Regina SK
    306-502-9103
    ------------------------------



  • 18.  RE: Re-veneering front arm curves

    Posted 11-13-2020 10:24
    poop...my PDF disc only goes up to 1999. Can we access back journals on the PTG website somewhere?

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



  • 19.  RE: Re-veneering front arm curves

    Posted 11-13-2020 12:11
    Yes. Is this year, you can access everything from 1979 to the present right here  Look for Journal under communities.

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    Floyd Gadd
    Regina SK
    306-502-9103
    ------------------------------



  • 20.  RE: Re-veneering front arm curves

    Posted 11-13-2020 12:38
    I looked there,  but 2003 shows no documents. There are pdfs back to 2008 but it seems to stop there. Are you viewing it off the website right now?

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



  • 21.  RE: Re-veneering front arm curves

    Posted 11-13-2020 13:21
    I'm working on my desktop computer.  When I click 2003 on the left side, the number 2003 appears on the right side of the screen.  When I click on that right-hand 2003, the pdfs appear on the left.

    ------------------------------
    Floyd Gadd
    Regina SK
    306-502-9103
    ------------------------------



  • 22.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-13-2020 13:06
    Jim,
    First you need to make the veneer more pliable in order to bend around the curve. That can be done by wetting or steaming the veneer and then clamping with a caul which matches that curve exactly. The hardest part is making the caul to match. Typical glues for woodworking can be used once you have a good clamping method.

    There are pliable veneers sold but the likelihood of matching what is out there to your specific piano is slim to none.

    Jeannie Grassi
    PTG Registered Piano Technician
    206-842-3721
    grassipianos@gmail.com




  • 23.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-13-2020 13:50
    Jim,

    Which curve are we talking about...the single swooping curve of the early 20th century, or the multi-humped curve of the Victorian era?

    Pwg

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



  • 24.  RE: Re-veneering front arm curves

    Posted 11-13-2020 14:52
    single swoop...20's L

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



  • 25.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-13-2020 15:40

    Hi, Jim

    I haven't replaced the entire veneer for a cheek, and my possible approach would probably require you to try the technique on some kind of dummy case part made of scrap, a few times.

    Back when I was writing for the Journal (about 1977) my first article was about the effect which could be obtained by mixing white glue (or carpenters glue) with water thin CA glue.

    For this job, the benefit would be very fast set up time, combined with what can often be quite a strong bond.

    My own experience with this has been when the veneer was all there, but the glue had failed so it was loose till about half way up the arm. I took a fairly thin thickness gauge (from a set used to work on car valves), put some white glue on it, both sides, and ran it up between the veneer and the case, repeating till I had a reasonably even coat on the whole surfaces. Then, harder, having cleaned off the thickness gauge very carefully, I put dots of CA glue on one side of it, pulled the veneer slightly up, and slide the thickness gauge along the upper portion, near where the veneer was still glued down. Having removed the gauge, I pressed the part with the CA under it against the case till it set (a few seconds), then cleaned the thickness gauge again, added more, and gradually worked down to the front in a couple more stages.

    The point being, for veneer which is still attached but loose, on a case part which cannot be clamped, once the two glues interact with each other, a strong reaction occurs. You can even feel the heat through the veneer as you press it. It's not too hard to press the veneer into the curve for long enough, using both hands.

    Well, it might be of dubious merit as a technique for this particular problem, but it would have the advantage of being unlike anything else you could try. It does take very little time, and if the results are not good, carefully prying with a thin piece of metal (like the thickness gauge) will allow you to remove the part and try again, if done in the first few minutes after gluing it down. Removing the glues after taking the veneer back off might offer some difficulty.

    Same thing with ivories -- if one goes on crooked (with the white glue on the keystick and the dots of CA on the back of the ivory), it is possible to take a thin knife and slide it back off. After 1/2 hour that would be harder to do, and the next day one would risk cracking the ivory.






  • 26.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-13-2020 18:44
    Piece of cake. Still recommend using crossbanding underneath. Today's veneers are much thinner than what they used back then.  Do the vertical front face first, then overlap with the top curved one, then the top vertical overlapping that, first with cross banding (you can use the exact same stuff for that or poplar, just 90° to the decorative top piece), trim and repeat with the final veneer. 

    With hammer veneering you coat both sides of the veneer with glue, the top side lubricated the hammer action. It also makes the veneer flexible and keeps it from curling since you have same moisture on both sides. 

    Pwg

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



  • 27.  RE: Re-veneering front arm curves

    Posted 11-13-2020 21:02
    I don't get the cross laminated part, because the 1st lamination will be long grain the length of the curve...and the veneer doesn't really like to bend tight radii along the grain. The top layer was grain perpendicular to the length of the arm, so I can see that bending well.

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



  • 28.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-13-2020 22:28
    With thin veneer it's not that hard. Crossbanding lends stability to the top veneer. The original was probably about 1/20" thick (or thicker). What you will be using is probably closer to 1/30" or thinner. I have sometimes used 1/40" mahogany as crossbanding. Very easy to bend once it's wet. Standard cabinetry protocol. 

    Pwg

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



  • 29.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-14-2020 07:15
    Jim,

    You are correct about the long grain piece not liking to bend well. This is likely why SS did not do it, as it would at least double the amount of time and labor needed for that job (they did of course crossband all their large flat pieces since these move A LOT with seasonal change). Likely they concluded that since their rim construction was super solid, the didn't need to worry about crossbanding, and it would easily last the 40 year design lifespan they intended. 

    Kevin Hancock Refinisher Extraordinaire in MD was the one who taught me about this. I have done it ever since. It just adds an extra layer (like a shock absorber) of insurance for that nice piece of mahogany or walnut or whatever that you're going to put on there. 

    Pwg

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



  • 30.  RE: Re-veneering front arm curves

    Posted 11-17-2020 17:53
    So many ideas have been shared here...thanks.

    Here's another, from Craig Hair and Richard Blais at Hampshire piano. They do piano conservation work. They tried numerous techniques and finally settled on a caul type technique that solved the problem that arises with cauls. The problem is that the radii of the cauls has to  match the raidus not of the arm but of the arm plus the veneer(s). If not, the caul fit will not be an real cope and pattern, and there will be gaps in the pressing. I had this problem the first time I tried using a caul. So, here is their technique, which they shared privately, but okay'd me to share on the website:

    "Hey Jim, gluing veneer on these curved surfaces was problematic, until a wooden cauld rough cut, "band saw" was pressed into place with layers of paper wet with water and a little glue to make it sticky.
    The paper mache is layered to the thickness of the veneer and a little wider than the area.
    When the paper mache is the proper thickness of the veneer to be pressed on it is important to include the paper thickness of the glue barrier that will be used when pressing on the veneer to be used.
    In this case the "arms" then this wet sticky paper is laid in place of the veneer, the glue makes for it staying in place. The wooden cauld is buttered very thinly with bondo, then the cauld is clamped in place, on to the paper mache squishing the excess bondo out the sides.
    When the bondo sets, and is not completely hardened, remove the clamp, the paper mache which was in place of the veneer will let go and can be discarded, leaving the perfect contoured surface, to match the veneer thickness when curved. And now is the time to trim excess plastic from sides of the cauld.
    The veneer can now be pressed without gaps in the curvature, of course a paper between cauld and veneer.
    The same thing has to be done on both sides, because they are never perfectly the same,----gaps usually occur, soooo. the same wooden cauld can be used for both sides. And the bondo can be removed with a heat gun or torch, about 180 deg, or so and it gets very soft to be able to remove it easily. "chizel"
    Should you decide to go this route ----then I would be glad to help.
    It makes for a good solid jointing, also we probably have vintage veneer here to match, there is no way in hell match this with newly acquired material, without a little color magicianship.
    Be well!"

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



  • 31.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-17-2020 22:19
    This papier mache system sounds good to me. I will try it.
    Has anyone tried sand bags and a caul? I have had good success with sand bags and weights as well as cauls on difficult surfaces.
    Nancy Salmon






  • 32.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-17-2020 23:30

    very clever






  • 33.  RE: Re-veneering front arm curves

    Posted 11-18-2020 07:02
    In a field veneer repair on curved cheeks, I cut two pieces of plywood to the curve. I clamped them to the inside and outside of the arm. Then I inserted push pins every 10 mm or so along the curve. I used old credit cards. (cut to the width) to press against the glueing veneer. Then, I strung rubber bands across the cheek between the push pins.  I have since deleted the photos. It work very well and the veneer is still holding after about ten years.

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
    ------------------------------



  • 34.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-18-2020 10:47
    Pretty cool idea...yes.

    If though (in the future), in anticipation of the repair, you make your cauls BEFORE removing the original veneer, you have your real world pattern already in the bin. In addition, if you construct it such that it is slightly flexible (cutouts in strategic places) and line it with cork, you will have a reasonably re-useable caul as well. 

    Pwg

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



  • 35.  RE: Re-veneering front arm curves

    Posted 11-18-2020 11:10
    The thin plastic cards conform to the curve and do not get stuck to the surface.
    The plywood is roughly cut to match the curve since its only job is to anchor the pins.

    ------------------------------
    Regards,

    Jon Page
    mailto:jonpage@comcast.net
    http://www.pianocapecod.com
    ------------------------------



  • 36.  RE: Re-veneering front arm curves

    Registered Piano Technician
    Posted 11-18-2020 18:41
    This may be useful for this application. I've been experimenting with using thermoplastics for making ad hoc molds and forms. PVC is ubiquitous, being used for most of the white plastic bottles (like bleach bottles) we have around the house. I've been cutting and saving the larger ones as sheets, 5 gallon bucket material works too. They get soft quickly with a heat gun. This could possibly be a quicker replacement for the paper mâché forms etc.

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    Steven Rosenthal
    Honolulu HI
    808-521-7129
    ------------------------------