On Thu, 7 Aug 2008 20:09:49 -0700 (PDT), "nailshooter41@[EMAIL PROTECTED]
"
<nailshooter41@[EMAIL PROTECTED]
> wrote:
>On Aug 7, 7:23 pm, Robatoy <Counterfit...@[EMAIL PROTECTED]
> wrote:
>
>> The drawback, of course, is that when you use biscuits to make a
>> panel, you can see the telegraphed shape of the biscuit after you sand
>> and finish the panel.
>
>No kidding... I haven't had that happen but once. Are you seeing this
>on a particular kind of wood or some size of glue up?
>
>I know there are those that have this problem all the time, but I also
>know that you undoubtedly buy the good biscuits and are careful (as
>you cautioned above) about the installation technique.
>
>I may not have this problem because 1) I am lucky! or 2) I dry fit the
>biscuits before I put them in the glue. If they don't slip in and out
>with just a little friction, they don't get used.
>
>I only use the PC biscuits (I see you use Lamello) and quit using the
>"bag o' biscuits" when a great deal of them didn't fit right, weren't
>****pped properly (sealed containers) and they were crumbly.
>
>Remember when companies like PC had actual, live tool reps, not 23
>year old guys with degrees in marketing that simply filled out
>customer orders?
>
>I went to a "PC Days" thing they had at Woodcraft many, many years ago
>and he told me their were three things that screwed up biscuit joinery
>(certainly not saying here that you are doing any of these!):
>
>- Folks don't use enough biscuits (at 0.03 a whack, that one made me
>LMAO)
>
>- They don't get the depth right (addressed by you)
>
>- And they don't store the biscuits properly
>
>According to the guy, the reason sPC went to the little clear bottles
>was to cut down on breakage, but more im****tantly keep the moisture
>out of the biscuits. Swelling of the biscuits was a known problem and
>PC apparently got a ton of them back as returns.
>
>His opinion was that if you have to tap a biscuit in, it is too
>tight. He swore that tight biscuits (don't even go there,
>buddy... ;^) ) were the problem that caused their shape to be
>reflected through the wood due to their expansion when hit with the
>glue.
>
>Your thoughts?
>
>Robert
Not to jump in but let's remember that a properly conceived biscuit is
cut in section more or less at the point between quartersawn and
plainsawn.
The natural expansion properties of such a biscuit make it expand in a
predictable manner that does not transmit the expansion line to the
face, if the face is more than 2X away from the thickness of the
biscuit, which it should always be. This holds true for both
laminated and solid goods.
Where I have seen bumps in the joint line they have invariably been
the result of positioning of the biscuit too close to the face, or to
using poor quality biscuits.
I use an antique Lamello Top 10 and always use the Lamello plates. I
bought a couple of tubes of the PC variety and found that they did not
mike out to a consistent thickness. I also found that too many of the
plates were flatsawn, or close to flatsawn, and that made them
unacceptable.
I keep my unused plates in a container with several SilicaGel bags
that help keep the moisture content down to less than 4%. I also
throw in a cheap hygrometer ($6.00) to make sure that moisture is not
an issue.
Your friend is right about tapping the plates in; they are no good if
they need more than a gentle push to insert them.
Lamello used to have standards on their website to let you know if the
biscuits had gone out of spec.
Regards, Tom.
Thos. J. Watson - Cabinetmaker
http://home.comcast.net/~tjwatson1/
tjwatson1ATcomcastDOTnet
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