Glue for laminated rib construction

[Farrell]

> Terry...regarding the color of the Unibond, have you tried controlling 
> glue line
> color by using different colored catalysts, which Vacupress supplies? I 
> use the
> dark catalysts for mahogany. There is a light catalyst for light 
> woods...but
> maybe that's what you've already tried. Don't know if there are more than 
> 1
> light catalyst.

Yup. I use their "white" catalyst when laminating spruce and maple. The 
"white" catalyst is YELLOW in color! Better than dark red/brown for sure, 
but really quite yellow. Like I say though, it doesn't bother me - rather it 
has a very functional appearance.

Terry Farrell

----- Original Message ----- 
From: <jimialeggio5 at comcast.net>
To: <pianotech at ptg.org>
Sent: Thursday, October 11, 2007 9:17 AM
Subject: Glue for laminated rib construction


> I"ve used both the Uni-bond 800 UF and Gorilla glue for all kinds of 
> laminations
> curved and otherwise. Both perform under exterior high moisture conditions 
> and
> sun cycling with no creep.
>
> Of the 2 I like the polyurethane for its machinability in secondary 
> operations.
> Its often my favorite choice for this reason, even though it is a pain to
> spread. ---An 8" very flexible drywall knife wiped cross grain helps move
> this part along considerably.
>
> I really like the Uni-bond 800 for the ease of getting the glue spread on 
> a
> bunch of laminations very quickly. I also really like its rigidity, 
> especially
> on curved laminations. Its only real down side from my perspective is it 
> is
> really hard on knives for secondary operations. I only use it where 
> secondary
> planing/jointing/shaping operations will be performed by carbide tooling. 
> I
> and haven't noticed any clogging issues on the drilling front.
>
> Terry...regarding the color of the Unibond, have you tried controlling 
> glue line
> color by using different colored catalysts, which Vacupress supplies? I 
> use the
> dark catalysts for mahogany. There is a light catalyst for light 
> woods...but
> maybe that's what you've already tried. Don't know if there are more than 
> 1
> light catalyst.
>
> Dale...the Unibond does have some out-gassing to it during use. I'm pretty
> sensitive to these things, but it doesn't seem to irritate my 
> sensitivities.
>
> I agree will you, Dale about epoxy...I never use it for anything other 
> than
> fixing boo-boo's, and very occasional minor structural gap filling.  It 
> really
> wants a thick glue line...for this reason I will not use it on joinery.
>
> As a side note, in the historic preservation field, in the late 80's early 
> 90's
> epoxy was embraced as a cure all for all kinds of difficult, skill 
> intensive
> repair issues in buildings. Since then, much time hase been spent fixing 
> failed
> epoxy work...mostly with close fitting goints replacing the monolithic 
> epoxy
> constructions.
>
> Jim I
>
>
>
>
> Even clamping pressure would concern me also. I not suggesting that you 
> can't
> successfully use Bolduc glue for a pinblock. For building pinblocks, 
> because of
> the clamping issue, I use either epoxy or 2-part urea-formaldehyde (UF)
> adhesive. The UF is water cleanup. It cures rock hard and can fill any 
> size gap.
> No actual clamping pressure is required (just like epoxy) - you really 
> only
> clamp to position things and so that you don't have more glue than wood.
>
> The UF adhesive I use is Unibond 800 
> http://www.vacupress.com/veneerglue.htm
> Very easy to use.
>
> You can also use the UF for ribs - although it leave a yellow glue line. 
> Doesn't
> bother me, but it is yellow.
>
> I've also used Bolduc and Titebond Extend for laminating ribs. Both work 
> well. I
> have had a few slabs of ribs change curvature while the wood MC 
> equilibrates
> with the shop. No real big deal, but if you use these water-based glues I 
> simply
> suggest waiting a week or two before using them - recheck the radius to be 
> sure
> of what you have. The UF avoids this concern (real or imagined).
>
> Terry Farrell
>  ----- Original Message ----- 
>  I've used the Bolduc glue for pinblock lamination for several years when 
> I'm
> oversizing them or building up multi-level blocks. The only issue for me 
> is even
> clamping pressure and the size of the panels that I've been working with 
> since I
> don't have a full soundboard press system (still buying them from Andre 
> with
> nary a complaint other than I ache to be making them myself :-). I don't 
> see why
> it wouldn't work with rib stock laminates as well. As I recall, Andre told 
> me
> several years ago when I was interviewing him for the Journal that he uses 
> his
> own glue for the pinblocks he makes as well. You might ask him.
>
>  Paul
>
>
>
>
>
>  -----Original Message-----
>
>    Belly heads
>    I've been gluing up my own laminated rib stock & my pinblocks.  I 
> won't use
> epoxy because it too is toxic to my body & expensive.  I'm open for 
> suggestions.
>     I need to glue up a bunch of ribs  tomorrow.  I like th Bolduc for my
> pinblocks & bridge cap applications because it doesn't clog drill bits or 
> have
> adverse affects on tuning torque.  I believe Andre usu to glue up his own 
> blocks
> & panels.
>    Any help?
>    Thanks
>    Dale
>