Stan wrote:
Help! I've been building a dining room table that is 5ft square made of
hard maple. I've followed the directions in my FWW mags and books to
the letter. I've alternated the grain but with the climate change, my
table top has curled up ALOT. Now there are 4 separate areas where the
6inch wide boards, which were biscuited, glued, and clamped, have
become separated at the ends, perhaps 1 to 4 inches into the table from
the edge. A gap exists between 1/16 and 1/8". Now what? The only
thing I can think of is to somehow get glue back in this tiny crack and
then re-clamp. Please offer me your good suggestions. Thanks,
-Clueless


Stan:

People would need a lot more information to help.

How thick is the wood?
What type of glue?
How much climate change? What was the humidity change -- best guess...
Kiln dried wood? Air dried? (And if so how long (i year per inch?)...)
Did you let the wood sit in your workshop before you cut and glued? How
long if so?
How long did it take to come apart? Immediately, a week?
Is it (was it) installed in the frame of the table or just sitting out
somewhere...



It does sound like a moisture/humidity issue -- not that I have ever
made this kind of mistake -- just heard about it. :-))

I think my maple table is narrower boards.

You'll get lots of opinions...


--
Will
Occasional Techno-geek

Boards are 1-1/8" thick. Glue is Titebond III. Current measurement in
my shop is ~40% Rh and in the winter it was in the 20s but it has gone
higher in the past week. Wood was supposedly kiln dried but probably
sat in an open door barn for years. It sat in my shop for months
before planing and sat there for months after being planed and jointed
before I glued it up. I noticed a very slight crack weeks ago but just
noticed the big ones yesterday, along with the severe curling. It is
just sitting out on my work bench.
Stan

Stan wrote:
Boards are 1-1/8" thick.

Glue is Titebond III.

Current measurement in
my shop is ~40% Rh and in the winter it was in the 20s but it has gone
higher in the past week.

Wood was supposedly kiln dried but probably
sat in an open door barn for years. It sat in my shop for months
before planing and sat there for months after being planed and jointed
before I glued it up.

I noticed a very slight crack weeks ago but just
noticed the big ones yesterday, along with the severe curling. It is
just sitting out on my work bench.
Stan


Stan:

Hope you see George's answer by now.

Also - I think you are saying that you glued it and it sat for "quite a
while"???

BTW -- Seasonal change is what you mean. (Climate is long term... :-) ) FWIW

After you look at George's response think about.... Is it possible that
you had a number of factors at work?

A) it was "too cold"
b) Clamped too hard (Just tight enough to squeeze excess glue is best
b) The glue was old or bad or maybe not quite as good as possible...
c) A quick moisture change along with the above

It seems like "too much" of a failure considering that you tried to take
reasonable care.

Maybe your timing on the gluing was just terrible -- i.e. way too cold
--- and then the seasonal change hit and you got too much stress.

Also -- If I cannot immediately smooth and finish these types of pieces,
I have taken to sealing the wood ends quickly after gluing up long
pieces -- just to make sure that "rapid" humidity changes don't cause
problems.



--
Will
Occasional Techno-geek

Will,
When I glued it up was in the middle of winter (very cold here near
Lake Ontario), but we experienced a couple of days of warm (above 60F)
weather so I took my chance and glued up. The harsh cold that followed
may have caused stress. The glue was brand new. I may have clamped
too hard.

I'm thinking about either taking a syringe or a small pump with a
needle that is used to inflate balls and tires and putting glue into
it, inserting the needle in the crack, and then pumping in the glue and
then clamp. Another thought is to drill a small hole from the side or
bottom and insert the glue enough to spread it around and then
re-clamp.
Stan

Stan wrote:
Will,
When I glued it up was in the middle of winter (very cold here near
Lake Ontario), but we experienced a couple of days of warm (above 60F)
weather so I took my chance and glued up. The harsh cold that followed
may have caused stress. The glue was brand new. I may have clamped
too hard.

I'm thinking about either taking a syringe or a small pump with a
needle that is used to inflate balls and tires and putting glue into
it, inserting the needle in the crack, and then pumping in the glue and
then clamp. Another thought is to drill a small hole from the side or
bottom and insert the glue enough to spread it around and then
re-clamp.
Stan


I am about 70 KM north of Lake Ontario so I understand. Brrr! We get
large temp and humidity swings as well. During the winter my wooden
planes closed up on the blades. Had to widen the mouths. 20% humidity as
I recall.

My recommendation is to take the other posters recommendations very
seriously.

Rip it down the glue line and do a complete re-glue. An afternoons work
and you should be out of the problem. I suspect that it will not clamp
tight right now. You can test to see. Never had any luck myself with
what you are suggesting. Also -- when you separate the pieces you may
find that a piece is twisted -- then the problem would be obvious.

If you can see a gap in an otherwise beautiful table in a couple of
years it will just p**s you off no end. LOL

Maybe George will also say something -- he seems to know what he is
doing... :-)


--
Will
Occasional Techno-geek

"WillR" wrote in message
.. .
Stan wrote:
Help! I've been building a dining room table that is 5ft square made of
hard maple. I've followed the directions in my FWW mags and books to
the letter. I've alternated the grain but with the climate change, my
table top has curled up ALOT. Now there are 4 separate areas where the
6inch wide boards, which were biscuited, glued, and clamped, have
become separated at the ends, perhaps 1 to 4 inches into the table from
the edge. A gap exists between 1/16 and 1/8". Now what? The only
thing I can think of is to somehow get glue back in this tiny crack and
then re-clamp. Please offer me your good suggestions. Thanks,
-Clueless


Stan:

People would need a lot more information to help.

How thick is the wood?
What type of glue?
How much climate change? What was the humidity change -- best guess...
Kiln dried wood? Air dried? (And if so how long (i year per inch?)...)
Did you let the wood sit in your workshop before you cut and glued? How
long if so?
How long did it take to come apart? Immediately, a week?
Is it (was it) installed in the frame of the table or just sitting out
somewhere...



Thickness - immaterial as long as acclimatized
Glue - Certainly
Humidity change - had to sometime, will again
Kiln/Air dried - immaterial, so long as it _was_ dry
Acclimatized - possible problem if it wasn't stickered, leaving some wood
much wetter
Speed of Self-Destruction - possibly significant


When you say 4" from the ends of the glueups - assuming glueups, no
breadboard - then I tend to think that the biscuits are centered about inch
five, and you've had glue failure. If it were cold when you glued up, you
might have problems. If things have become damp since, especially if the
parts that have separated have been near the floor where it changes most,
might also have a problem. If boards were poorly joined and squeezed into
submission, especially hard maple, which doesn't soak up glue much, could
also be a player.

Now, if the wood was inadequately acclimatized, you might have some problems
as well. Tension relief on the drying boards might have pulled them away
from the others - but only if the glue failed.

Alternating "smiles" are really not important. More important is broad to
broad grain, quarter to quarter.