Glue cleanup on Ribs

[Overs Pianos]

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Dale, Terry and all,

For the board we just glued up last week for piano no. 4, we used 
Titebond Extend with the vacuum press (the very first sound board to 
be assembled in this press). We left it in the press for nearly an 
hour before taking it out to clean up.

Since I was somewhat worried about having insufficient glue for a 
good joint between the ribs and the panel, I applied the glue a 
little thicker with the roller, when compared to the amount applied 
to the sound board test strips over the month before. So for most 
ribs there was a glue bead which required cleaning up. Fortunately, 
the Titebond bead remained quite milky even though the ribs were 
quite firmly glued to the panel. We used a sharp chisel to remove the 
bulk of the bead, then a 50/50 water metho mix for cleaning away the 
remaining glue. The metho mix improved slightly the ability to soften 
the glue for its removal with a scraper. Furthermore, the metho 
prevented any blue-stain problems from developing during the cleanup.

By the way, regarding the moisture content of the panel prior to 
gluing, after some experimentation we decided to take it down to only 
7%. With a laminated panel, there is minimal dimensional change with 
moisture content variation. For those who are inclined to use the 
more predictable and reliable RC type of sound board construction, 
the laminated panel would seem to be an excellent choice. It must 
surely produce sound boards with superior tuning stability 
characteristics, and I can see no tonal disadvantages through using 
laminated over solid panels.

There was some discussion earlier this year about the possibility of 
fully floating the ribs (ie. having them finish out on the sound 
board panel before they reached the inner rim) when using laminated 
panels, since the panel would be resistant to splitting (Del wrote a 
couple of good posts on the topic). After considering the options, I 
decided in this instance to err on the side of caution by running the 
ribs fully out over the inner rim. Actually, this choice also 
assisted gluing the panel together in the vacuum press, since the 
full length ribs (which were feathered after being glued) were able 
to support the panel right out to the edges of the panel.

In the case of this piano, the ribs will not be notched into the 
inner rim as is usual. Instead, we have glued perimeter hardwood 
spacers to the panel in between the ribs to elevate the feathered 
ribs to just above the inner rim. This method of sound board 
installation was used previously by Welmar/Marshall & Rose in their 
grand pianos. The technique is particularly advantageous in instances 
where one is joining the inner and outer rims before gluing in the 
belly, since it eliminates the necessity of cutting rib notches into 
the inner rim prior to fitting the board. Furthermore, it becomes an 
easy matter to revise the rib layout should you wish to modify the 
sound board design at a later stage.

There are probably a 100 other approaches besides the above, but for 
what its worth.

That's a very nice tool in the link below Terry, and an excellent idea indeed.

Best,

Ron O.

>For occasions where dried glue squeeze-out is present, perhaps a 
>"SMALL CHISEL PLANE", such as the one available from Lie-Nielsen, 
>would do the trick. 
><http://www.lie-nielsen.com/tool.html?id=97-1/2&cart=1064226782381>http://www.lie-nielsen.com/tool.html?id=97-1/2&cart=1064226782381
>
>Terry Farrell
>
>----- Original Message -----
>From: <mailto:Erwinspiano@aol.com>Erwinspiano@aol.com
>To: <mailto:pianotech@ptg.org>pianotech@ptg.org
>Sent: Saturday, September 20, 2003 1:00 AM
>Subject: Glue cleanup on Ribs
>
>   For those of you who are pressing your own soundboards I'd like to 
>compare notes as to how you all go about cleaning up the glue 
>squeeze at the glue joints. I've done it two ways.
>     I've  used a go- bar deck and currently a fire hose neumatic 
>press. Cleanup with a go-bar deck as you go is easy because of 
>access but with a pneum. press the 2 by 6s are in the way. It's 
>possible just awkward and have done it alot.
>     I've typically taped off the rim and rib glue jointson the 
>bottom of the board, pinned the ribs to the board, then I tape over 
>the rib ends before spraying on a coat of shellac. I find that this 
>makes glue cleanup easier and resist moisture absorption 
>I've usually have used cold hide glue and tried to limit the glue 
>squezze out. Then I wipe it up/off with damp/dry paper towells.
>   I recently used tight bond 2 to glue up ribs on a S&S B.  I waited 
>till the glue squeeze beads jelled. After about 4 hr.s a sharp 
>chisel was used to cleanup the excess(which was like strings of 
>rubber) but I was un happy with the minor damage to the panel. A 
>final sanding and one more coat of shellac is applied before final 
>finish but.....
>     The upside to hide glue is ease of cleanup. The down side is 
>using some moisture in cleanup as  the board is ribbed which can be 
>moderated by drying the board a bit more before pressing.
>    I like the idea and strength of the tight bond 2. It does not 
>cleanup as eaily with the towell method however.
>     Ideas?
>      Dale Erwin


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