Terry, Thanks for your reply. Yes, I did hand drill. Although the drill felt pretty tight in the hole when bottomed out I suppose that could be it. But it seems more likely the dowel was undersized as you suggest. I will put a micrometer on the remainder when I get home tonight, just to satisfy my curiosity. The dowel was purchased at Home Depot, and was advertised as "hardwood;" I assume perhaps maple. Where does one get a red oak dowel? Paul Milesi, RPT Washington, DC (202) 667-3136 E-mail: paul at pmpiano.com Website: http://www.pmpiano.com > From: Terry Farrell <mfarrel2 at tampabay.rr.com> > Reply-To: <pianotech at ptg.org> > Date: Fri, 30 Apr 2010 16:06:27 -0400 > To: <pianotech at ptg.org> > Subject: Re: [pianotech] Glue Strength for Pedal Lyre Repair > > Paul - Thanks for posting the pics - worth a zillion words. I have > found that it is not common to get a perfectly clean break in a piece > of wood like this. Typically there will be enough irregularities and > splinters that make a perfect fit impossible. In all honesty, from > looking at your pics, the break does appear fairly clean - maybe the > pieces did mate up just about perfectly. In that case, wood glue > should work. However, I would always use epoxy on a break such as > this. Wood glue is not strong at all when it has to bridge any gaps. > Appropriate epoxy is very strong that way. I just chisel off the > irregularities and splinters and then epoxy together - that way you're > guaranteed a super-strong repair - and with the lyre, you certainly > want that. > > Regarding the loose dowels. If you hand drilled, that is likely a good > part of the reason. Another is maybe the dowel is slightly undersized. > What kind of wood was the dowel? Yes, you do want a tight fit for wood > glue. Here again, I would drill the hole oversize, use a RED OAK dowel > (super strong and porous for epoxy to grip) and epoxy it in place > using the West System two step bonding method (same for the block). > That will give you the strongest possible repair. > > Wood glue (Titebond) has it's place, and it could work well here, but > it wouldn't be my first choice. > > Terry Farrell > > On Apr 30, 2010, at 11:38 AM, Paul Milesi, RPT wrote: > >> Many thanks to all who contributed to my education the past couple >> of days! >> I ended up gluing the two original top block pieces together, >> clamped for 24 >> hours, then drilled and inserted three 1/2" hardwood dowels. >> Finally, I put >> a little stain on the dowel ends to blend them with the lyre finish >> (refinished years ago by somebody else). >> >> While aware of Steinway lyre construction using posts and wedges, I >> thought >> it best not to remove remaining top block piece from posts or remove >> the >> wedges. I felt re-inserting wedges after gluing the top block might >> split >> my glue joint open again. I just tried to take advantage of the wide >> surface area between the two pieces to achieve a good glue joint. >> >> Question about the doweling: When I drilled the 1/2" holes, my >> dowels were >> a little lose, not a tight fit that needed to be pounded or squeezed >> in. I >> assume with enough glue, this is OK? When I use hammer shanks for >> wood >> filler, the shanks are generally tight in the hole I've drilled. >> Not sure >> why these turned out differently. If anybody reads this paragraph, >> I'd sure >> appreciate insight into whether tight fit is necessary, and how to >> best >> achieve it. Thinking about this because I know clamping a glue >> joint is so >> important. >> >> Pix attached. >> >> Paul Milesi, RPT >> Washington, DC >> (202) 667-3136 >> E-mail: paul at pmpiano.com >> Website: http://www.pmpiano.com >> >> < >> P4280230 >> .jpg >>> >> <P4280232.jpg><P4300235.jpg><P4300238.jpg><P4300237.jpg><P4300243.jpg> > >
This PTG archive page provided courtesy of Moy Piano Service, LLC