I glued up a panel of spruce using TBIII. It has been stored inside for 20
years (the first 18 as part of a neighbor's staircase) so it is dry.
When I trimmed the ends, the pieces fell apart. That has never happened to
me in the hundreds of hardwood panels I have done, so I was very surprised.
Each side has glue on it, but it just didn't hold.
I clamped the panel to a table and pushed down on it and the joint opened
up. I think it is only held together by the three biscuits I put in. Now I
wish I had used four!
What caused this? I glued up some pine before and it did fine; is it
something about spruce?
I have a very thin glue/chalk (Captain Tolley, if you have never heard of
it, it is great product) and laid some in while opening up the joint a hair.
Now I am gently clamping and hoping I can salvage these panels. I will know
in a few hours.
Those would be my first questions, with special emphasis on how old the
glue was, and how it had been stored. Also as suspicioned above, in
my experience, cold weather makes proper adhesion much more difficult.
Way down south here we don't have the luxury of all the hardwoods at
our disposal, so in the early day of building we had a lot of spruce
and pine used. When properly prepared (just like any other wood;
clean, joined properly, etc.) I have found that he glue joint was
actually stronger than the wood.
everything was maybe 65 degrees.
I used it a couple days ago for 4 viraro panels under the same conditions,
and they are perfect; well, at least the cutoffs held together normally, so
I trust they are perfect.
Something ain't right ...
Only you can make the decision, but, if it's an important project, and
considering what happened to your cutoff ends, I would give some serious
thought to re-ripping the glue lines on the TS and re-gluing the panels. You
can easily re-cut your biscuits in the same slots if you don't have room for
Much easier now if you're in the glue-up mode, than at some future date.
BTDT ... more than once. Good luck in any event.
it apart, and clamped it. The cutoffs from the other side seem pretty good
with the new glue (I cut one end and stopped in distress when the cutoffs
But no, I don't trust it. I stuck a bunch of pocket screws in to be sure.
They are shelves in a table going behind the couch, so there won't be much
of any load and will never be seen. Between the biscuits and the pocket
screws it has to be good.
I just wish I knew what caused the problem; it had to be something about the
spruce. I guess I will play around with some of the spruce scraps. Or
maybe I will see how good TB's customer service is.
Did you re-joint the edges of those 20 year old boards before gluing? Wood
that sits too long (and 20 years is plenty long) often won't take glue. A
quick test is to put a drop of water on the edge. If it stays beaded up
like the board was waxed.... not a good sign.
Hope that helps. Otherwise, I've nothing. It's a mystery.
Even that may not be enough with a resinous wood like spruce. Water-based
glues will find no way in, even on surfaces minimally joined, a process that
produces some heat and flow on a machine, and lotsa drag on a plane.
I am dying it with a water based dye to "match" the viraro top I am putting
on, and it stains okay; so it will take some water. Maybe just not enough
for a glue bond.
(I am building a couch table; the only thing that will ever be seen is the
top, so I am using up some spruce for the legs and shelves; as much to get
rid of it as to save money.)
OK, I'm slow on the uptake--I finally figured out what "TBIII" is... :)
I would think it _should_ work fine. There are a lot of different
woods that could be sold under the general moniker of "spruce" and some
are more resinous than others. I can't think of any specific spruce
I've used TB III w/, but have with a lot of pines and other "white
woods" which typically are mixtures of spruce/hemlock/??? and also w/
Doug fir with no real problems.
I did a quick look on the Titebond site and didn't find any
proscription against spruce or other similar woods. It does point out
in general application notes for TB III that soft woods do need lower
clamping pressures as opposed to hardwoods, so there is that variable
to consider. Also, it does note that for oily or high in tannic acid
to use a wipe of acetone before gluing to provide a clean surface for
adhesion. Might investigate those factors.
There is a technical service link to them at the site as well. If
nothing else is uncovered, might be worth a query w/ the problem. Will
be most interested to learn what you learn (as I'm sure, most other
regulars will be, too)...
Resins are waterproof. They're also prone to migrate to the surface over
time, as all who've had them bleed through a finish can testify. As
indicated in my post, _might_ be a problem, even for wood given a thin pass
over the jointer to freshen the edge.
Let me reiterate - this is speculation, just as the age of the glue and the
temperature of the surroundings have been speculation. The makers of the
glue properly caution against excessive clamping pressure, as this will
compress the dampened fibers of softwoods like squeezing a sponge.
Still didn't hear what kind of glue which would be interesting to
Other possibilities could include excessive clamping pressure resulting
in too much squeeze out or not enough glue to begin with.
Oh, another thought--not a polyurethane glue, perchance? They rely on
moisture for a cure and 20 yr old material might be really, really dry
on the surface and not get a good "cure".
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