New to making dovetails...using bandsaw (yes, cheating). Directions for
dovetails, bandsaw or not, is they are cut at an angle to the face.
Is the purpose of this so the joint locks together or just for looks? Seems
like a 90 degree cut, for both pins and tails, would be fine for a "low
load, light stress" situation...
Dovetails are cut the way they are for strength reasons. The sort of joint
you describe is commonly called a box joint. It is almost as strong but
many people think it is not as attractive.
"Chris Carruth" <[email protected]> wrote in message
news:[email protected]...
> New to making dovetails...using bandsaw (yes, cheating). Directions for
> dovetails, bandsaw or not, is they are cut at an angle to the face.
>
> Is the purpose of this so the joint locks together or just for looks?
Seems
> like a 90 degree cut, for both pins and tails, would be fine for a "low
> load, light stress" situation...
>
>
>
A dovetail is just that-- been used for many years. If cut properly,
they lock together quite nicely with a minimum of glue.
"like a 90 degree cut, for both pins and tails, would be fine for a
"low
load, light stress" situation..."
The description above is for box joints -- easy to do on the TS with a
simple jig don't bother with the bandsaw on these. Either will work,
dovetails are more elegant.
For a low load light stress situation you can use simple rabbets & glue
with nails- particularly if you don't care what they look like & have a
lot to make. You could also look at the drawer lock mitering bit for
routers (never used one), but the result looks interesting in the
catalogs.
"Chris Carruth" <[email protected]> wrote
: New to making dovetails...using bandsaw (yes, cheating). Directions for
: dovetails, bandsaw or not, is they are cut at an angle to the face.
:
: Is the purpose of this so the joint locks together or just for looks?
Seems
: like a 90 degree cut, for both pins and tails, would be fine for a "low
: load, light stress" situation...
The chief value of the interlocking feature of dovetails is that it greatly
assists assembly at glueing up time.
For information about the strength in relation to the splay angle, please
look at my web site - Dovetailing Detailed - Dovetail Angles.
Jeff G
--
Jeff Gorman, West Yorkshire, UK
Email: username is amgron
ISP is clara.co.uk
www.amgron.clara.net
toller wrote:
> A dirty little secret is that with modern glue, butt joints are all
you
> need. Anything more sophisticated is purely for looks and the
builder's
> satisfaction.
>
> Don't believe it? Make some butt joints, let them dry for 48 hours,
and try
> to break them apart. The wood will tear out before the joint fails.
Okay,
> other joints may be even stronger, but so what; isn't that adequate?
Just because the wood might tear out before the glue doesn't mean the
joint is just as strong. When a butt joint tears out, it tears out on
the piece with the end grain showing, and the tear is with the grain.
If you make a box or dovetail jig, the ONLY way to break the joint is
to break it against the grain. It is MUCH strong.
"toller" <[email protected]> wrote in message
news:[email protected]...
>A dirty little secret is that with modern glue, butt joints are all you
>need. Anything more sophisticated is purely for looks and the builder's
>satisfaction.
>
> Don't believe it? Make some butt joints, let them dry for 48 hours, and
> try to break them apart. The wood will tear out before the joint fails.
> Okay, other joints may be even stronger, but so what; isn't that adequate?
>
> That said, on a recent project I mismeasured and didn't have enough wood
> for anything but a butt joint (I pocket screwed them because the inside
> wasn't visible) Everytime I pass it (a dog food station) I get a little
> upset at how ugly it is. The only thing stopping me from rebuilding it is
> that no one else sees the problem.
The glue is not the problem. It is the weakness of the wood that you are
trying to over come in a stronger joint.
Leon wrote:
snip
> The glue is not the problem. It is the weakness of the wood that you are
> trying to over come in a stronger joint.
You use GLUE to hold things together? What if you want to take
the thing apart later? GLUE!?
Seriously, aside from the mechanical strength of a dovetailed
joint, through & half blinds are self squaring, something you
don't get with box/finger joints. That keeps things from racking.
I've made a seven overlay drawer unit under my drill press.
Half blinds on the front, throughs on the back - no glue.
Been using those drawers for a couple of years and they
work fine - without ANY glue.
Have also made a handful of chisel racks, some with box/
finger joints and some with through dovetails. By not gluing
them, it's easy to modify them as my chisel collection/obsession
grows.
charlie b
<[email protected]> wrote in message
news:[email protected]...
>
> toller wrote:
>> A dirty little secret is that with modern glue, butt joints are all
> you
>> need. Anything more sophisticated is purely for looks and the
> builder's
>> satisfaction.
>>
>> Don't believe it? Make some butt joints, let them dry for 48 hours,
> and try
>> to break them apart. The wood will tear out before the joint fails.
> Okay,
>> other joints may be even stronger, but so what; isn't that adequate?
>
> Just because the wood might tear out before the glue doesn't mean the
> joint is just as strong. When a butt joint tears out, it tears out on
> the piece with the end grain showing, and the tear is with the grain.
>
> If you make a box or dovetail jig, the ONLY way to break the joint is
> to break it against the grain. It is MUCH strong.
>
I didn't say it was just as strong; in fact I stated that other joints were
stronger. Its just that a butt joint is often strong enough.
Addressing the OP's issue, it would be unusual to fine a situation where box
joints were not strong enough. I just made some box-jointed boxes out of
3/8" wood and, just for fun, found I could stand on the setup pieces without
breaking. Yes, a dovetail is stronger still, but usually the only reason
for using it is appearance.
"Chris Carruth" <[email protected]> writes:
> New to making dovetails...using bandsaw (yes, cheating). Directions for
> dovetails, bandsaw or not, is they are cut at an angle to the face.
>
> Is the purpose of this so the joint locks together or just for looks?
It looks good.
It also provides strength without requiring glue.
Over time, glues (especially old ones) weaken.
Dovetails are very good for drawers, because it resists coming
apart when something heavy hits the back wall.
> Seems
> like a 90 degree cut, for both pins and tails, would be fine for a "low
> load, light stress" situation...
Yup. Many old "practical" boxes use the machine-cut box joints.
But old drawers with box joints come apart.
--
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A dirty little secret is that with modern glue, butt joints are all you
need. Anything more sophisticated is purely for looks and the builder's
satisfaction.
Don't believe it? Make some butt joints, let them dry for 48 hours, and try
to break them apart. The wood will tear out before the joint fails. Okay,
other joints may be even stronger, but so what; isn't that adequate?
That said, on a recent project I mismeasured and didn't have enough wood for
anything but a butt joint (I pocket screwed them because the inside wasn't
visible) Everytime I pass it (a dog food station) I get a little upset at
how ugly it is. The only thing stopping me from rebuilding it is that no
one else sees the problem.