>The biscuits do absolutely nothing as far as strength is concerned
But they sure make it a lot easier to align the boards...
This comment is typically made about biscuits. Most often when referring to
gluing together a top etc.
Saying this too often will eventually give the idea to the newbie that there
is no reason to own a biscuit joiner. Biscuits can successfully replace M&T
joints in many places. They are faster $$$$ and easy to make etc. They are
most useful when making kitchen cabinet boxes, face frames etc.
Don't be misled as to how worthless biscuits are! They can be your friend
$$$$$!
--
Rumpty
Radial Arm Saw Forum: http://forums.delphiforums.com/woodbutcher/start
- - - - - - - - - - - - - - - - - - - - -
"SonomaProducts.com" <[email protected]> wrote in message
news:[email protected]...
> Here are two scientifc studies.
>
> http://journals.tubitak.gov.tr/agriculture/issues/tar-04-28-5/tar-28-5-2-0311-1.pdf
>
> http://www.woodworking.org/WC/GArchive98/1_17ring.html
>
> The first is about biscuits in corner joints of Particle Board and MDF
> furniture. It basicially says Biscuits actually weaken the joint so
> wider spacing of biscuits leavs more room for edge gluing.
>
> The second is a study in solid wood, replacing tenon joinery for entry
> type door frames. In this case they show how going to 3 biscuits is
> actually nearly as strong as a tenon in Pine. The most interesting
> facts from this study are that putting the biscuit deeeper in the edge
> grain side is more effective (see how the joist fail by tearing the
> edge grain) and that the gap at the bottom of the slot is another weak
> point so poly glue might be better, as it fills gaps better (still not
> good). Epoxy might be best huh?
>
Both studies make sense. Biscuits significantly increase the glue surface.
In solid wood that makes it stronger. In particle board that makes it
weaker.
Agreed. I use biscuits all the times (well, almost), especially when
the goal of the project is the "end product". Frankly, I feel that
other joineries like dovetails, through tenons, box joints, etc. are
pretty much "just for show" rather than the necessity in many
applications (except for reproduction work.)
I guess I'm going to get heat by saying this ..
Here are two scientifc studies.
http://journals.tubitak.gov.tr/agriculture/issues/tar-04-28-5/tar-28-5-2-0311-1.pdf
http://www.woodworking.org/WC/GArchive98/1_17ring.html
The first is about biscuits in corner joints of Particle Board and MDF
furniture. It basicially says Biscuits actually weaken the joint so
wider spacing of biscuits leavs more room for edge gluing.
The second is a study in solid wood, replacing tenon joinery for entry
type door frames. In this case they show how going to 3 biscuits is
actually nearly as strong as a tenon in Pine. The most interesting
facts from this study are that putting the biscuit deeeper in the edge
grain side is more effective (see how the joist fail by tearing the
edge grain) and that the gap at the bottom of the slot is another weak
point so poly glue might be better, as it fills gaps better (still not
good). Epoxy might be best huh?
BW
I agreed with you on the M&T for chairs and tables, that's why I wrote
"many applications" not "all applications". But I think I should be
more clear; I was thinking about dovetail joints for a jewelry box or
drawers in a side table that get opened a few times a week.
It's like shooting birds with missiles..
toller wrote:
> "SonomaProducts.com" <[email protected]> wrote in message
> news:[email protected]...
<snip>
> Both studies make sense. Biscuits significantly increase the glue surface.
> In solid wood that makes it stronger. In particle board that makes it
> weaker.
How does increasing glue surface in pb make the joint weaker?
Curiously,
H.
A few years ago Norm was using more biscuits than Uneeda could bake.
(We old timers know the reference here :)) Then someone said he wasn't
too keen on them lately because of "swelling problems" or somesuch.
What is his position now?
Biscuits sure beat a butt joint but I personally think they sometimes
make panel alignment more complicated. Perfect alignment during glue
drying can be had with clamps and cauls.
FoggyTown
I'm torn,
Yes they add stregnth...no they don't add stregnth. What's a poor
newbie to do. I was planning a coffe table with a shelf. As I don't
have the skills to do a good M&T yet and I don't want to waste wood
(makore), I thought I would use biscuits on the stretchers between to
legs. I'm concerned about the amount of shear the joint will be able
to handle with the weight of the wood and 100 of SWMBO's magazines
piled on the shelf (I'm not concerend about the table top as it is
supported by the legs).
I think I've determined that I shouldn't use the biscuits and should
just keep practising my M&T's tell I get it right. Thoughts?
BobS <[email protected]> wrote:
> Ahhhhhhhh yup (heat that is...;-)
>
> There was an article a couple of years back in one of the trade mags, plus
> there's a ww site (that I can't find at the moment - but will try if needed)
> that ran a test on the various types of woodworking joints. From dowels to
> variations of the M&T and the test included biscuits.
>
> Certainly you can use them for joinery but if good strength is necessary for
> the joint - then biscuits are a poor choice. A rail and stile cabinet door
> doesn't have or need much strength in it's joints in a typical cope and
> stick construction but make that a deeper M&T joint and it is one of the
> strongest joints available. A biscuit added to a butt joint (rail to stile
> for instance) certainly adds some strength (end-grain to long-grain glue
> joint) but it was not much according to the test results as I recall.
I remember an article in Fine Woodworking where they tested the strength
of various jointing methods and biscuits were one of the strongest
joints...
Here is is, it was in the April 2001 issue:
https://www.taunton.com/store/shoppingcart/ssl/tplus.asp?GoToOnSuccess=/
store/shoppingcart/online_selection_validation.asp
I have it somewhere in paper form but can't find it at the moment.
--
mare
On Sun, 29 May 2005 16:29:44 GMT, jo4hn <[email protected]> wrote:
<snip>
>Didn't somebody here come up with some study that proved that biscuits
>in a joint are actually stronger than glue alone? Or is age causing a
>brain fart?
> twitch,
> jo4hn
I recall Fine Woodworking published a study of various
(non-mechanical) joints. Mortise and tenon was the strongest and when
it failed, it did so slowly. The joint held together by biscuits was
surprisingly strong as a T-joint but when it failed, it did so without
much warning. For an edge-to-edge joint, biscuits add a little
additional strength over a plain butt joint. Biscuits work
exceptionally well with MDF and chipboard where other types of joints
often fall short. A butt joint is the weakest of all as there is less
glue surface area. It is the glue-surface area that effects overall
strength, and since bicuits increases glue area it adds strength,
similar to a spline.
On Fri, 27 May 2005 12:52:41 -0400, "Rumpty" <[email protected]> wrote:
>>The biscuits do absolutely nothing as far as strength is concerned
>But they sure make it a lot easier to align the boards...
>
>This comment is typically made about biscuits. Most often when referring to
>gluing together a top etc.
>
>Saying this too often will eventually give the idea to the newbie that there
>is no reason to own a biscuit joiner. Biscuits can successfully replace M&T
>joints in many places. They are faster $$$$ and easy to make etc. They are
>most useful when making kitchen cabinet boxes, face frames etc.
>
>Don't be misled as to how worthless biscuits are! They can be your friend
>$$$$$!
I'm far from an expert, but for me, biscuits replaced dowels... I'm probably the
only one in the world that can use precision power tools, a dowel jig and a
drill press, and still not have parts line up.. *g*
mac
Please remove splinters before emailing
On Tue, 31 May 2005 17:42:26 -0400, Odinn <[email protected]> wrote:
> I have a friend, who when given a marked board and a chop saw and the
> board placed there by the carpenter/cabinet builder/whatever, who will
> ALWAYS come up with a short board. We don't allow him to assist in
> anything that requires cutting, drilling, screwing, etc. He's only
> allowed to hand us the lumber or screws or whatever.
We built an addition in our fire department a year or three ago, and I
scheduled a work-day on a saturday to get some help. I was amazed that
more than a couple of the guys _could not measure_. Boards were coming
up plus or minus 1/4 inch, I have no clue WTF they were doing but I gave
'em something less technical to do.
CrackedHands wrote:
>
> I agreed with you on the M&T for chairs and tables, that's why I wrote
> "many applications" not "all applications". But I think I should be
> more clear; I was thinking about dovetail joints for a jewelry box or
> drawers in a side table that get opened a few times a week.
>
> It's like shooting birds with missiles..
Well, there's such a thing as aesthetics in design, too, I've heard....
:)
hylourgos wrote:
>
> toller wrote:
> > "SonomaProducts.com" <[email protected]> wrote in message
> > news:[email protected]...
> <snip>
>
> > Both studies make sense. Biscuits significantly increase the glue surface.
> > In solid wood that makes it stronger. In particle board that makes it
> > weaker.
>
> How does increasing glue surface in pb make the joint weaker?
>
It doesn't...it's a misinterpretation of the results of the test...
In the MDF joint, the thickness of the remaining material around the
biscuit slot was insufficient given the strength of MDF. Wood w/ its
continuous fibers isn't subject to same problem.
mac davis wrote:
> On Fri, 27 May 2005 12:52:41 -0400, "Rumpty" <[email protected]> wrote:
>
>
>>>The biscuits do absolutely nothing as far as strength is concerned
>>
>>But they sure make it a lot easier to align the boards...
>>
>>This comment is typically made about biscuits. Most often when referring to
>>gluing together a top etc.
>>
>>Saying this too often will eventually give the idea to the newbie that there
>>is no reason to own a biscuit joiner. Biscuits can successfully replace M&T
>>joints in many places. They are faster $$$$ and easy to make etc. They are
>>most useful when making kitchen cabinet boxes, face frames etc.
>>
>>Don't be misled as to how worthless biscuits are! They can be your friend
>>$$$$$!
>
>
> I'm far from an expert, but for me, biscuits replaced dowels... I'm probably the
> only one in the world that can use precision power tools, a dowel jig and a
> drill press, and still not have parts line up.. *g*
>
I have a friend, who when given a marked board and a chop saw and the
board placed there by the carpenter/cabinet builder/whatever, who will
ALWAYS come up with a short board. We don't allow him to assist in
anything that requires cutting, drilling, screwing, etc. He's only
allowed to hand us the lumber or screws or whatever.
--
Odinn
RCOS #7
"The more I study religions the more I am convinced that man never
worshipped anything but himself." -- Sir Richard Francis Burton
Reeky's unofficial homepage ... http://www.reeky.org
'03 FLHTI ........... http://www.sloanclan.org/gallery/ElectraGlide
'97 VN1500D ......... http://www.sloanclan.org/gallery/VulcanClassic
Atlanta Biker Net ... http://www.atlantabiker.net
Vulcan Riders Assoc . http://www.vulcanriders.org
rot13 [email protected] to reply
Ahhhhhhhh yup (heat that is...;-)
There was an article a couple of years back in one of the trade mags, plus
there's a ww site (that I can't find at the moment - but will try if needed)
that ran a test on the various types of woodworking joints. From dowels to
variations of the M&T and the test included biscuits.
Certainly you can use them for joinery but if good strength is necessary for
the joint - then biscuits are a poor choice. A rail and stile cabinet door
doesn't have or need much strength in it's joints in a typical cope and
stick construction but make that a deeper M&T joint and it is one of the
strongest joints available. A biscuit added to a butt joint (rail to stile
for instance) certainly adds some strength (end-grain to long-grain glue
joint) but it was not much according to the test results as I recall.
The dovetail makes a good strong joint for many applications where
pull-apart strength is a necessity - such as in drawers. Yes, other joinery
can be used but I would disagree with your statement about being "just for
show". You only need to look at some of the works by Sam Maloff and look
closely at the joints he uses in his chairs for instance. Not much to see
unless you pull it apart or see it before it's assembled but they're
dovetails and M&T's and nothing shows. He uses them for strength and does
not draw attention to them.
Bob S.
"CrackedHands" <[email protected]> wrote in message
news:[email protected]...
> Agreed. I use biscuits all the times (well, almost), especially when
> the goal of the project is the "end product". Frankly, I feel that
> other joineries like dovetails, through tenons, box joints, etc. are
> pretty much "just for show" rather than the necessity in many
> applications (except for reproduction work.)
>
> I guess I'm going to get heat by saying this ..
>
On 31 May 2005 22:02:52 GMT, Dave Hinz <[email protected]> wrote:
>On Tue, 31 May 2005 17:42:26 -0400, Odinn <[email protected]> wrote:
>
>> I have a friend, who when given a marked board and a chop saw and the
>> board placed there by the carpenter/cabinet builder/whatever, who will
>> ALWAYS come up with a short board. We don't allow him to assist in
>> anything that requires cutting, drilling, screwing, etc. He's only
>> allowed to hand us the lumber or screws or whatever.
>
>We built an addition in our fire department a year or three ago, and I
>scheduled a work-day on a saturday to get some help. I was amazed that
>more than a couple of the guys _could not measure_. Boards were coming
>up plus or minus 1/4 inch, I have no clue WTF they were doing but I gave
>'em something less technical to do.
murphy says that the wider the board, the more likely someone who doesn't know
better will measure diagonally..
mac
Please remove splinters before emailing
On 1 Jun 2005 07:34:53 -0700, "mrcomp_ca" <[email protected]> wrote:
>I'm torn,
>
>Yes they add stregnth...no they don't add stregnth. What's a poor
>newbie to do. I was planning a coffe table with a shelf. As I don't
>have the skills to do a good M&T yet and I don't want to waste wood
>(makore), I thought I would use biscuits on the stretchers between to
>legs. I'm concerned about the amount of shear the joint will be able
>to handle with the weight of the wood and 100 of SWMBO's magazines
>piled on the shelf (I'm not concerend about the table top as it is
>supported by the legs).
>
>I think I've determined that I shouldn't use the biscuits and should
>just keep practising my M&T's tell I get it right. Thoughts?
I don't know if this will help, but it helped me...
when I got my 1st biscuit jointer, I made a sample frame out of 1/3 fir, using a
#10 biscuit in each corner and titebond III...
I let it sit a few days, then put it in the vice and started applying a r9ocking
motion to it like a bookcase or cabinet might get when moved...
It took a while, but I got all 4 corners loose, and every one broke the wood
around the joint, not the biscuit.. those lil' suckers really glue in there!
mac
Please remove splinters before emailing
mac davis wrote:
> On Fri, 27 May 2005 12:52:41 -0400, "Rumpty" <[email protected]> wrote:
>
>
>>>The biscuits do absolutely nothing as far as strength is concerned
>>
>>But they sure make it a lot easier to align the boards...
>>
>>This comment is typically made about biscuits. Most often when referring to
>>gluing together a top etc.
>>
>>Saying this too often will eventually give the idea to the newbie that there
>>is no reason to own a biscuit joiner. Biscuits can successfully replace M&T
>>joints in many places. They are faster $$$$ and easy to make etc. They are
>>most useful when making kitchen cabinet boxes, face frames etc.
>>
>>Don't be misled as to how worthless biscuits are! They can be your friend
>>$$$$$!
>
>
> I'm far from an expert, but for me, biscuits replaced dowels... I'm probably the
> only one in the world that can use precision power tools, a dowel jig and a
> drill press, and still not have parts line up.. *g*
>
I beg to differ.
>
>
> mac
>
> Please remove splinters before emailing
--
Will
Occasional Techno-geek
"jo4hn" <[email protected]> wrote in message
news:[email protected]...
> Rumpty wrote:
>>>The biscuits do absolutely nothing as far as strength is concerned
>>
>> But they sure make it a lot easier to align the boards...
>>
>> This comment is typically made about biscuits. Most often when referring
>> to
>> gluing together a top etc.
>>
>> Saying this too often will eventually give the idea to the newbie that
>> there
>> is no reason to own a biscuit joiner. Biscuits can successfully replace
>> M&T
>> joints in many places. They are faster $$$$ and easy to make etc. They
>> are
>> most useful when making kitchen cabinet boxes, face frames etc.
>>
>> Don't be misled as to how worthless biscuits are! They can be your friend
>> $$$$$!
>
> Didn't somebody here come up with some study that proved that biscuits in
> a joint are actually stronger than glue alone? Or is age causing a brain
> fart?
> twitch,
> jo4hn
jo4hn, your brain is working just fine. There are numerous studies of
biscuits and joint strength. You might start, as I just did, by Googleing
with[ "biscuit joinery" joint strength study] in the search criteria[just
use what is in brackets]. You can find more if you massage the search words
a bit.
Larry
--
Columbia, MO
www.llhote.com
"Rumpty" wrote in message
> >The biscuits do absolutely nothing as far as strength is concerned
> But they sure make it a lot easier to align the boards...
>
> This comment is typically made about biscuits. Most often when referring
to
> gluing together a top etc.
But a comment not necessarily "typically made" by anyone who knows what
they're talking about. On long grain to long grain glueups, like on the
table top in your quoted text first above, the quote is basically correct
with regard to both "strength" and "alignment".
... you did you just want an argument, right? ;)
--
www.e-woodshop.net
Last update: 5/14/05
Loose tenons. Google Beadlock.
"mrcomp_ca" <[email protected]> wrote in message
news:[email protected]...
> I'm torn,
>
> Yes they add stregnth...no they don't add stregnth. What's a poor
> newbie to do. I was planning a coffe table with a shelf. As I don't
> have the skills to do a good M&T yet and I don't want to waste wood
> (makore), I thought I would use biscuits on the stretchers between to
> legs. I'm concerned about the amount of shear the joint will be able
> to handle with the weight of the wood and 100 of SWMBO's magazines
> piled on the shelf (I'm not concerend about the table top as it is
> supported by the legs).
>
> I think I've determined that I shouldn't use the biscuits and should
> just keep practising my M&T's tell I get it right. Thoughts?
>
Biscuits will work well on the stretchers and also on the apron to leg
joint. If your apron is approx. 4" a #20 should be used, but an S-6
biscuit works best. http://csaw.com/beechbiscuit.html
--
Rumpty
Radial Arm Saw Forum: http://forums.delphiforums.com/woodbutcher/start
- - - - - - - - - - - - - - - - - - - - -
"mrcomp_ca" <[email protected]> wrote in message
news:[email protected]...
> I'm torn,
>
> Yes they add stregnth...no they don't add stregnth. What's a poor
> newbie to do. I was planning a coffe table with a shelf. As I don't
> have the skills to do a good M&T yet and I don't want to waste wood
> (makore), I thought I would use biscuits on the stretchers between to
> legs. I'm concerned about the amount of shear the joint will be able
> to handle with the weight of the wood and 100 of SWMBO's magazines
> piled on the shelf (I'm not concerend about the table top as it is
> supported by the legs).
>
> I think I've determined that I shouldn't use the biscuits and should
> just keep practising my M&T's tell I get it right. Thoughts?
>
"mrcomp_ca" <[email protected]> wrote in news:1117636493.789674.223330
@g14g2000cwa.googlegroups.com:
> I'm torn,
>
> Yes they add stregnth...no they don't add stregnth. What's a poor
> newbie to do. I was planning a coffe table with a shelf. As I don't
> have the skills to do a good M&T yet and I don't want to waste wood
> (makore), I thought I would use biscuits on the stretchers between to
> legs. I'm concerned about the amount of shear the joint will be able
> to handle with the weight of the wood and 100 of SWMBO's magazines
> piled on the shelf (I'm not concerend about the table top as it is
> supported by the legs).
>
> I think I've determined that I shouldn't use the biscuits and should
> just keep practising my M&T's tell I get it right. Thoughts?
>
I'm not sure of your table design, and so cannot comment on that,
however:
Dowels are still considered 'old school' at some of the 'fine
woodworking' programs of note. And that is a term of pride, son.
For those without a wizened old mentor, you might look at the Miller
Dowel system, as a means of making a strong, beautiful, repeatable
joint. I haven't tried it yet, but several of my experienced
woodworking friends in analog life have, and speak of it with high
regard.
I have used traditional dowels, with good results, and would do so
again. And I built bathroom vanity drawers with rabbets and biscuits in
the project currently on my bench, because my dovetail jig would not
accomodate the thick stock I had already cut to less than jointer
length. And I didn't want to hand cut DTs for 8 drawers in a bathroom.
Just a thought. No financial interest, etc.
Patriarch
Rumpty wrote:
>>The biscuits do absolutely nothing as far as strength is concerned
>
> But they sure make it a lot easier to align the boards...
>
> This comment is typically made about biscuits. Most often when referring to
> gluing together a top etc.
>
> Saying this too often will eventually give the idea to the newbie that there
> is no reason to own a biscuit joiner. Biscuits can successfully replace M&T
> joints in many places. They are faster $$$$ and easy to make etc. They are
> most useful when making kitchen cabinet boxes, face frames etc.
>
> Don't be misled as to how worthless biscuits are! They can be your friend
> $$$$$!
Didn't somebody here come up with some study that proved that biscuits
in a joint are actually stronger than glue alone? Or is age causing a
brain fart?
twitch,
jo4hn
Lawrence L'Hote wrote:
> "jo4hn" <[email protected]> wrote in message
> news:[email protected]...
>
>>Rumpty wrote:
>>
>>>>The biscuits do absolutely nothing as far as strength is concerned
>>>
>>>But they sure make it a lot easier to align the boards...
>>>
>>>This comment is typically made about biscuits. Most often when referring
>>>to
>>>gluing together a top etc.
>>>
>>>Saying this too often will eventually give the idea to the newbie that
>>>there
>>>is no reason to own a biscuit joiner. Biscuits can successfully replace
>>>M&T
>>>joints in many places. They are faster $$$$ and easy to make etc. They
>>>are
>>>most useful when making kitchen cabinet boxes, face frames etc.
>>>
>>>Don't be misled as to how worthless biscuits are! They can be your friend
>>>$$$$$!
>>
>>Didn't somebody here come up with some study that proved that biscuits in
>>a joint are actually stronger than glue alone? Or is age causing a brain
>>fart?
>>twitch,
>>jo4hn
>
>
> jo4hn, your brain is working just fine. There are numerous studies of
> biscuits and joint strength. You might start, as I just did, by Googleing
> with[ "biscuit joinery" joint strength study] in the search criteria[just
> use what is in brackets]. You can find more if you massage the search words
> a bit.
> Larry
>
I published a note to a fine wood working book at one time. Some other
person posted the FWW Magazine article, and then a follow-up article I
believe.
See Practical Design -- Solutions and Strategies
From FWW
Article Choosing the Strongest Joinery for Doors
Page 52
Rail & Stile type joint.
Dowel -- 1800 lbs.
Loose Tenon & M&T 2500 Lbs.
Two Biscuits 2700
Three Biscuits 2900
I think the test was redone with slightly different results -- but not
significant for most applications.
--
Will
Occasional Techno-geek
On 28 May 2005 18:20:15 -0700, "hylourgos" <[email protected]> wrote:
>
>
>toller wrote:
>> "SonomaProducts.com" <[email protected]> wrote in message
>> news:[email protected]...
><snip>
>
>> Both studies make sense. Biscuits significantly increase the glue surface.
>> In solid wood that makes it stronger. In particle board that makes it
>> weaker.
>
>How does increasing glue surface in pb make the joint weaker?
>
>Curiously,
>H.
I betcha it has more to do with the material <removed> by the
cutter....
"mrcomp_ca" <[email protected]> wrote in message
>
> Yes they add stregnth...no they don't add stregnth. What's a poor
> newbie to do. I was planning a coffe table with a shelf. As I don't
> have the skills to do a good M&T yet and I don't want to waste wood
You're going to have to make up your own mind, but consider this. There's a
great deal of woodworkers out there (and here) that own and use biscuit
joiners. I'm one of them. I'd wager that most of owners of these machines
use them for edge joining boards to make wider panels just like the one
you're considering. If these panels were prone to easy failure or extremely
difficult to construct with the aid of a biscuit joiner, there would be a
whole lot of screaming going on. There isn't. Need I say more?
On Tue, 31 May 2005 14:17:34 -0400, WillR <[email protected]>
wrote:
<snip>
>> I'm far from an expert, but for me, biscuits replaced dowels... I'm probably the
>> only one in the world that can use precision power tools, a dowel jig and a
>> drill press, and still not have parts line up.. *g*
>>
>
>I beg to differ.
>
>
damn, Will.. we're just too much alike.. rofl
mac
Please remove splinters before emailing
On Sun, 29 May 2005 09:37:46 -0500, Duane Bozarth <[email protected]>
wrote:
>hylourgos wrote:
>>
>> toller wrote:
>> > "SonomaProducts.com" <[email protected]> wrote in message
>> > news:[email protected]...
>> <snip>
>>
>> > Both studies make sense. Biscuits significantly increase the glue surface.
>> > In solid wood that makes it stronger. In particle board that makes it
>> > weaker.
>>
>> How does increasing glue surface in pb make the joint weaker?
>>
>
>It doesn't...it's a misinterpretation of the results of the test...
>
>In the MDF joint, the thickness of the remaining material around the
>biscuit slot was insufficient given the strength of MDF. Wood w/ its
>continuous fibers isn't subject to same problem.
I know a fella who does great work making box frames using MDF. He uses a Dremel
as a slot cutter and fast setting epoxy and pennies for alignment.
"Upscale" <[email protected]> wrote in message
news:[email protected]...
>
> "mrcomp_ca" <[email protected]> wrote in message
>>
>> Yes they add stregnth...no they don't add stregnth. What's a poor
>> newbie to do. I was planning a coffe table with a shelf. As I don't
>> have the skills to do a good M&T yet and I don't want to waste wood
>
> You're going to have to make up your own mind, but consider this. There's
> a
> great deal of woodworkers out there (and here) that own and use biscuit
> joiners. I'm one of them. I'd wager that most of owners of these machines
> use them for edge joining boards to make wider panels just like the one
> you're considering. If these panels were prone to easy failure or
> extremely
> difficult to construct with the aid of a biscuit joiner, there would be a
> whole lot of screaming going on. There isn't. Need I say more?
>
>
Biscuits do add *some* structural strength, (long grain to long grain but
the total surface area of the biscuits is probably minimal compared to the
surface are of the boards to be glued. However one good reason to use them,
is that they stabilize the joint during glue up. Using modern glues, it's
been demonstrated time and time again that in long grain to long grain glue
joints, it's usually the wood itself that will fail before the glue joint
fails. While the biscuits probably don't add all that much to the strength
of the joint, they will aid dramatically in producing a perfectly flat
surface after gluing, (or one that needs minimal sanding). By always
cutting the biscuit slots from the top of the boards, this will account for
any minor variations in the width of the boards. If the application was so
extreme that wood failure is a possibility, (i.e. grandsons using a coffee
table as a launching platform to jump to the couch <G>) I wouldn't depend on
biscuits or dowels, but would cross brace the wood from the backside, maybe
even to the point of laminating a hardboard on the back. (Either that, or
traumatizing a grandson for life).*
However, I have used biscuits, with a good deal of success in strengthen end
grain to end grain on cabinet faceframes. In this particular instance, even
a single biscuit would almost double the glue surface. And if you're trying
to mount the face frames without nail holes, using biscuits to align the
faceframe to the cabinet carcass while the glue dries is invaluable.
IMHO, biscuits are normally an acceptable substitute for dowels, in most
instances. Most doweling jigs exactly center the holes in the boards and if
the boards aren't exactly the same thickness, this can produce minor, but
extremely annoying variations on the surface. Doweling jigs can be shimmed
to offset the holes, but you're really getting touchy here.
Just chatting. Not preaching.
James....
*Two weeks ago, a grandson of mine was using a lower cabinet door (walnut)
to climb on the kitchen cabinet to get to the cookies. The joints, nearest
the hinges failed, on the door. I was able to fix the door, and I'm
confident the repaired door will hold up just fine.
My grandson has a new found respect for Grandma's cabinets, too. One down.
Three to go.
On 1 Jun 2005 07:34:53 -0700, "mrcomp_ca" <[email protected]> wrote:
>Yes they add stregnth...no they don't add stregnth. What's a poor
>newbie to do.
Consider the biscuits to be first glued into the wood. I.E. suppose
them to be an integral part of the wood, being embedded in it. Now
examine the cross-section [edge-on] of the biscuits and the wood. The
area of wood far exceeds that of the biscuits. When glued, the area
of wood glued edge to edge far exceeds that of the biscuits in the
cross-sectional view. That is, the amount of glue on the wood to wood
area is the major factor in the gluing.
Look at the material used for biscuits. If it was steel, then it
would help strengthen the joint in that it would be less likely to
flex and so break, even at a slight distance from the joint within the
dimensions of the biscuit. The biscuit material is relatively so weak
that it does nothing of any consequence like that.
The biscuits help line up the material. Keep using them for that
purpose. I think they do a great job of that.
Now, this topic has been beaten to death over and over, so let's leave
it be and concentrate on more important topics like Antivirus
software, whether or not you need to learn AutoCad before you learn to
use a hammer, and religion B.S. and the other interesting OT redneck
discussions that fill this forum.
>A rail and stile cabinet door
doesn't have or need much strength in it's joints in a typical cope and
stick construction but make that a deeper M&T joint and it is one of the
strongest joints available
Double stack your biscuit and you have the strongest joint.
--
Rumpty
Radial Arm Saw Forum: http://forums.delphiforums.com/woodbutcher/start
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"Rumpty" <[email protected]> wrote in message
news:[email protected]...
> >The biscuits do absolutely nothing as far as strength is concerned
> But they sure make it a lot easier to align the boards...
Actually when used properly they add great strength to a mitered joint and
or or butt joints.
Rumpty wrote:
>>The biscuits do absolutely nothing as far as strength is concerned
>
> But they sure make it a lot easier to align the boards...
>
> This comment is typically made about biscuits. Most often when referring to
> gluing together a top etc.
>
> Saying this too often will eventually give the idea to the newbie that there
> is no reason to own a biscuit joiner. Biscuits can successfully replace M&T
> joints in many places. They are faster $$$$ and easy to make etc. They are
> most useful when making kitchen cabinet boxes, face frames etc.
>
> Don't be misled as to how worthless biscuits are! They can be your friend
> $$$$$!
>
> --
>
> Rumpty
>
> Radial Arm Saw Forum: http://forums.delphiforums.com/woodbutcher/start
>
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I built my workbench base with wedged tenons and I don't think I'd feel
safe having replaced them with biscuits. That being said, biscuits do
have their place. As a matter of fact, I did use them on the workbench
top to attach the aprons slightly offset at the top and then planed them
flush. That's one use for a biscuit that most other joinery can't do.