I've been chasing my tail trying to find the right place (/person) to cut up
some ¼", ½", & ¾" plywood so I can make some built-in cabinet drawers with
front lock joints, rear dados (or even possibly rabbet and dados), and
grooved bottoms.

I learned that Baltic Birch (BB) is a company and their products are .750"
if you buy 3/4". Same for 1/2" = .5"

I understand that if you are lucky enough to be using BB you can use a 1/2"
straight bit to cut dados to join a 1/2" rear into a 1/2" side drawer joint,
and the product will slide in with little (sanding maybe?), or no adjustment
for a TIGHT dado joint.

But it looks like I'll probably not be so lucky as to be getting BB cut up,
so I need to know what to do with the ¼"(double flute straight, & double
flute upspiral), ½"(double flute mortising-plungable) straight router bits I
have to deal with the fact that the plywood pieces I have cut to the right
sizes will not be ½", but likely say 1/16" or 1/32" less than .5". They are
titanium carbide bits and brand new, so I assume great cutting performance.



HERE IS MY QUESTION

I have a router table and I need to know how to make a TIGHT dado for
nominal ½" birch (not BB) plywood pieces. If I used my ½" straight bit the
joint would not be tight. I guess I could use my ¼" bit and move it over to
the right width; say 15/32". Or should I ensure I buy BB (.5") in the first
place, so I only have the ¼" depth to deal with in my routered dados. I am
not a practiced woodworker, but I do have knowledge of cnc machining in
metal, and know how to use woodworking tools. What am I looking at layering
wise? Two width cuts and three depth, and in what order?

Freud's router bit catalog lists 3/8", 7/16", and ½" straight bits only in
that order. Do I need another bit greater than my 1/4"s, & which one?

Whoops, Freud have a 15/32" "undersized plywood" bit on the next page. Is
this what I need. Is all undersized plywood the same under-size, and should
one setup produce a TIGHT joint?

END QUESTION

For the ¼" bottom grooves, I am assuming that it is fine to use a 1/4"
straight bit for the ¼" nominal bottom plywood, because it will be floating
(and expanding/contracting) in this groove anyway, and only supporting.

For the front lock joint I will be using my table saw, and will have to deal
with a 1/8" thick combination blade to make the ¼" wide cuts. To be dealt
with later.... I do not want to buy a stacking, or wobble blade, really; may
not keep the TS.

"bent" wrote in message

Whoops, Freud have a 15/32" "undersized plywood" bit on the next page. Is
this what I need. Is all undersized plywood the same under-size, and
should
one setup produce a TIGHT joint?

Freud and most every good router bit has them. www.infinitytools.com
www.routerbits.com are good sources.


END QUESTION

For the ¼" bottom grooves, I am assuming that it is fine to use a 1/4"
straight bit for the ¼" nominal bottom plywood, because it will be
floating
(and expanding/contracting) in this groove anyway, and only supporting.

Yes,


For the front lock joint I will be using my table saw, and will have to
deal
with a 1/8" thick combination blade to make the ¼" wide cuts. To be dealt
with later.... I do not want to buy a stacking, or wobble blade, really;
may
not keep the TS.

You may want to consider this:
http://www.infinitytools.com/products.asp?dept=1059

bent wrote:

I've been chasing my tail trying to find the right place (/person) to cut up
some ¼", ½", & ¾" plywood so I can make some built-in cabinet drawers with
front lock joints, rear dados (or even possibly rabbet and dados), and
grooved bottoms.

I learned that Baltic Birch (BB) is a company and their products are .750"
if you buy 3/4". Same for 1/2" = .5"

I understand that if you are lucky enough to be using BB you can use a 1/2"
straight bit to cut dados to join a 1/2" rear into a 1/2" side drawer joint,
and the product will slide in with little (sanding maybe?), or no adjustment
for a TIGHT dado joint.

But it looks like I'll probably not be so lucky as to be getting BB cut up,
so I need to know what to do with the ¼"(double flute straight, & double
flute upspiral), ½"(double flute mortising-plungable) straight router bits I
have to deal with the fact that the plywood pieces I have cut to the right
sizes will not be ½", but likely say 1/16" or 1/32" less than .5". They are
titanium carbide bits and brand new, so I assume great cutting performance.



HERE IS MY QUESTION

I have a router table and I need to know how to make a TIGHT dado for
nominal ½" birch (not BB) plywood pieces. If I used my ½" straight bit the
joint would not be tight. I guess I could use my ¼" bit and move it over to
the right width; say 15/32". Or should I ensure I buy BB (.5") in the first
place, so I only have the ¼" depth to deal with in my routered dados. I am
not a practiced woodworker, but I do have knowledge of cnc machining in
metal, and know how to use woodworking tools. What am I looking at layering
wise? Two width cuts and three depth, and in what order?

Freud's router bit catalog lists 3/8", 7/16", and ½" straight bits only in
that order. Do I need another bit greater than my 1/4"s, & which one?

Whoops, Freud have a 15/32" "undersized plywood" bit on the next page. Is
this what I need. Is all undersized plywood the same under-size, and should
one setup produce a TIGHT joint?

END QUESTION

For the ¼" bottom grooves, I am assuming that it is fine to use a 1/4"
straight bit for the ¼" nominal bottom plywood, because it will be floating
(and expanding/contracting) in this groove anyway, and only supporting.

For the front lock joint I will be using my table saw, and will have to deal
with a 1/8" thick combination blade to make the ¼" wide cuts. To be dealt
with later.... I do not want to buy a stacking, or wobble blade, really; may
not keep the TS.



Either buy plywood bits (a set of odd size router bits for undersized
sheet stock) or get a good dado blade set for your TS. Or get both.
(The one who dies with the most tools wins.)

Dave

w/r/t lock joint or mitre lock joint router bits, would you recommend one
over the other. I'll have 1/2" or ~1/2" sides and 3/4" or ~3/4" fronts. Is
one any stronger than the other. I have already read the setup of the mitre
lock so far. Not planning any overlay

Whoops, Freud have a 15/32" "undersized plywood" bit on the next page.
Is
this what I need. Is all undersized plywood the same under-size, and
should
one setup produce a TIGHT joint?

Freud and most every good router bit has them. www.infinitytools.com
www.routerbits.com are good sources.


Infinity has a 31/64" straight bit. Do I need to borrow a caliper? - I lost
my Mitutoyo.

ok, so what is it like to try to get a 1/4" wide by (I'm gonna say 1/4" deep
cut b/c I don't feel like digging out notes) out of a 1/8" wide combination
table saw blade in order to make a lock joint?L

I would not buy a dado blade if you are using only 1/4in dado. I would just
make two passes with my 1/8in blade.

Here is a link showing how to make the joint with a table saw.

http://www.diynetwork.com/diy/hi_too...219278,00.html

Dave Paine.

"bent" wrote in message
...
ok, so what is it like to try to get a 1/4" wide by (I'm gonna say 1/4"
deep
cut b/c I don't feel like digging out notes) out of a 1/8" wide
combination
table saw blade in order to make a lock joint?L

"bent" wrote in
:

I've been chasing my tail trying to find the right place (/person) to
cut up some ¼", ½", & ¾" plywood so I can make some built-in cabinet
drawers with front lock joints, rear dados (or even possibly rabbet
and dados), and grooved bottoms.

I learned that Baltic Birch (BB) is a company and their products are
.750" if you buy 3/4". Same for 1/2" = .5"

I understand that if you are lucky enough to be using BB you can use a
1/2" straight bit to cut dados to join a 1/2" rear into a 1/2" side
drawer joint, and the product will slide in with little (sanding
maybe?), or no adjustment for a TIGHT dado joint.


Another alternative in some cases it to use a smaller dado, say 3/8" for
your nominal 1/2" ply. You'd then need to rabbet the play to create a
tongue 3/8 thick which would then fit tightly into the dado.

bent wrote:

I've been chasing my tail trying to find the right place (/person) to cut up
some ¼", ½", & ¾" plywood so I can make some built-in cabinet drawers with
front lock joints, rear dados (or even possibly rabbet and dados), and
grooved bottoms.

I learned that Baltic Birch (BB) is a company and their products are .750"
if you buy 3/4". Same for 1/2" = .5"

I understand that if you are lucky enough to be using BB you can use a 1/2"
straight bit to cut dados to join a 1/2" rear into a 1/2" side drawer joint,
and the product will slide in with little (sanding maybe?), or no adjustment
for a TIGHT dado joint.

But it looks like I'll probably not be so lucky as to be getting BB cut up,
so I need to know what to do with the ¼"(double flute straight, & double
flute upspiral), ½"(double flute mortising-plungable) straight router bits I
have to deal with the fact that the plywood pieces I have cut to the right
sizes will not be ½", but likely say 1/16" or 1/32" less than .5". They are
titanium carbide bits and brand new, so I assume great cutting performance.



HERE IS MY QUESTION

I have a router table and I need to know how to make a TIGHT dado for
nominal ½" birch (not BB) plywood pieces. If I used my ½" straight bit the
joint would not be tight. I guess I could use my ¼" bit and move it over to
the right width; say 15/32". Or should I ensure I buy BB (.5") in the first
place, so I only have the ¼" depth to deal with in my routered dados. I am
not a practiced woodworker, but I do have knowledge of cnc machining in
metal, and know how to use woodworking tools. What am I looking at layering
wise? Two width cuts and three depth, and in what order?

Freud's router bit catalog lists 3/8", 7/16", and ½" straight bits only in
that order. Do I need another bit greater than my 1/4"s, & which one?

Whoops, Freud have a 15/32" "undersized plywood" bit on the next page. Is
this what I need. Is all undersized plywood the same under-size, and should
one setup produce a TIGHT joint?

END QUESTION

For the ¼" bottom grooves, I am assuming that it is fine to use a 1/4"
straight bit for the ¼" nominal bottom plywood, because it will be floating
(and expanding/contracting) in this groove anyway, and only supporting.

For the front lock joint I will be using my table saw, and will have to deal
with a 1/8" thick combination blade to make the ¼" wide cuts. To be dealt
with later.... I do not want to buy a stacking, or wobble blade, really; may
not keep the TS.



the closest I can come to 1/2" BB, is 12 MM. Are you sure you are
getting BB that is exactly ONE HALF inch thick?

Dave

Another alternative in some cases it to use a smaller dado, say 3/8" for
your nominal 1/2" ply. You'd then need to rabbet the play to create a
tongue 3/8 thick which would then fit tightly into the dado.

So thats why one would do that (me).

And apparently gluing surface is king.

the closest I can come to 1/2" BB, is 12 MM. Are you sure you are
getting BB that is exactly ONE HALF inch thick?

Dave

No, but I understand (since like weeks ago) this is one thing you can say
about Baltic Birch.

BB is always singled out. For plys, thickness, strength. It comes from one
place and/or one source.

|12mm| is less than |1/2"| by about 14 thou. I always remember that one
1/32" is approximately 1/33". 32s or 33s, who cares. And I know 1/33
divided by 1/33 is .99999... (1.0000...). So a 1/32" (1/33") descrimination
is like .033..."

14 thou is less than one half of 1/32". Less than a 1/64". Actually it is
1/7257143152"

Pretty good size, but will it fit? Maybe for a bottom. A 3-ring piece of
paper is about 3 thou. Five pieces may just hold the weight of itself from
falling out. I bet you the entire combined tolerance of the 75, 000
thousand machined parts in a Stealth fighter is less than that.

I haven't measured any sheets. I bet they are all different from each
other. Freud has an undersized plywood bit of 15/32". Infinity 31/64".
One guy said to use a sharpening service and a 1/2".

I love going to Home Depot and determining if you'll have to reverse
engineer your project when some guy sets your cut once on the wrong line.
He tells you if you're cutting an 8 foot long piece of ply four times
combined it's gonna be off by the thickness of the material. You ask, and
he says no problem. So he takes the first cut, lays out the tape measure and
exclaims PERFECT. Perfectly closer to the next closest line. Thats a buck.
Do you want the next fifteen?

I figured the panel saw out. For cutting horizontally there are two
platforms, and two reference rules. The rules don't move. One is to the
lower rest, the other to the upper rest, depending on the width of the sheet
and convenience. Absolute dimentions from bottom to top. No adding or
subtracting. No factoring in the blade. Because of gravity I draw all my
rips from bottom to top. The machine isn't set to measure the other way.
Maybe some employees would assume a perfect 48" and subtract if a drawing is
made that way. All dimensions should be contiguous, not combined, because
the top piece is removed after each cut. The thickness of the blade is zero
set. The rule never moves. 1/8" is set when the machine is built. That
is, with the needle pointer at 15-15/16", thats what you get. If you were
resting on the lower platform, say 30" away, use the other rule. It is
offset by 30" It would read 15-15/16", The machine cuts straight as an
arrow and perfectly normal.
With vertical cuts, the blade is slid over to a lock position and rides up
and down. The wood is slid side to side to a stop block. Accuracy of
consecutive cuts just depends on moving the wood over to lightly touch the
stop block. The rule for the stop block starts at zero and works both ways.
The blade is accounted for, the rules origins start .250" appart (two 1/8"
saw kerfs). The stop block is a steel fixture with a cam clamp that rides
on a rail. It is a bit figetty, but done firmly and right its all over.
The V and H rules are the same. and the indicating pointers are the same.
There is no paralax error to worry about. Pointer to rule is a fractions of
a millimeter. White steel rule with black graduations. Black spring steel
pointers. There is no operational errror introduced.

"bent" writes:


[...]


|12mm| is less than |1/2"| by about 14 thou. I always remember that one

No. 1/2"=12.7mm, 1/2"-12mm=.7mm approx 28 thou approx 1/36"

--
Dr. Juergen Hannappel http://lisa2.physik.uni-bonn.de/~hannappe
Phone: +49 228 73 2447 FAX ... 7869
Physikalisches Institut der Uni Bonn Nussallee 12, D-53115 Bonn, Germany
CERN: Phone: +412276 76461 Fax: ..77930 Bat. 892-R-A13 CH-1211 Geneve 23

ya. so a dozen sheets. I was using the decimal remainder from a 6mm vs.
1/4 BBvc pw source I found today for drawer bottoms

You'd loose that bet. You'd be surprised at how sloppy most of the
tolerences of aircraft parts are. +- .030 is common.
"bent" wrote in message
...
I bet you the entire combined tolerance of the 75, 000
thousand machined parts in a Stealth fighter is less than that.

On 12/13/2005 9:53 PM CW mumbled something about the following:
You'd loose that bet. You'd be surprised at how sloppy most of the
tolerences of aircraft parts are. +- .030 is common.
"bent" wrote in message
...
I bet you the entire combined tolerance of the 75, 000
thousand machined parts in a Stealth fighter is less than that.

Especially on a stealth plane such as the SR-71 Blackbird. The
component parts of the Blackbird fit very loosely together to allow for
expansion at high temperatures. At rest on the ground, fuel leaks out
constantly, since the tanks in the fuselage and wings only seal at
operating temperatures.

--
Odinn
RCOS #7 SENS BS ???

"The more I study religions the more I am convinced that man never
worshiped 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 to reply

You are confusing tolerance (allowable variation from the ideal) with
designed fit. They are not interchangeable though they each have a bearing
on the other.

"Odinn" wrote in message
...
On 12/13/2005 9:53 PM CW mumbled something about the following:
You'd loose that bet. You'd be surprised at how sloppy most of the
tolerences of aircraft parts are. +- .030 is common.
"bent" wrote in message
...
I bet you the entire combined tolerance of the 75, 000
thousand machined parts in a Stealth fighter is less than that.

Especially on a stealth plane such as the SR-71 Blackbird. The
component parts of the Blackbird fit very loosely together to allow for
expansion at high temperatures. At rest on the ground, fuel leaks out
constantly, since the tanks in the fuselage and wings only seal at
operating temperatures.

--
Odinn
RCOS #7 SENS BS ???

"The more I study religions the more I am convinced that man never
worshiped 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 to reply

On 12/14/2005 8:55 PM CW mumbled something about the following:
You are confusing tolerance (allowable variation from the ideal) with
designed fit. They are not interchangeable though they each have a bearing
on the other.

"Odinn" wrote in message
...
On 12/13/2005 9:53 PM CW mumbled something about the following:
You'd loose that bet. You'd be surprised at how sloppy most of the
tolerences of aircraft parts are. +- .030 is common.
"bent" wrote in message
...
I bet you the entire combined tolerance of the 75, 000
thousand machined parts in a Stealth fighter is less than that.
Especially on a stealth plane such as the SR-71 Blackbird. The
component parts of the Blackbird fit very loosely together to allow for
expansion at high temperatures. At rest on the ground, fuel leaks out
constantly, since the tanks in the fuselage and wings only seal at
operating temperatures.

I'm easily cornfused, what's new

--
Odinn
RCOS #7 SENS BS ???

"The more I study religions the more I am convinced that man never
worshiped 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 to reply