Hello experts,
I am new to woodworking and am trying to make a picture frame clamp, which calls
for 4 identical jaws or L-blocks with a 90 degree interior angle. The blocks
will each be cut from 3/4" stock 2"x2" square. I can either cut out the angles
first or cut out the 4 square blocks followed by cutting the interior angles
(which is preferred?)
What's the best method and tool to use to create these 4 identical 90 degree
L-shaped blocks? I guess what is more important is the exact 90 degree cut than
the shape or sizes of the 4 pieces. The 2 cuts are 1" into the block.
The tools I have at my disposal are: table saw, band saw, compound mitre saw,
and a router. If using the table saw, I would prefer clean cuts where the table
saw blade does not "run" or cut into the wood beyond the interior corner. I
tried making multiple passes using my table saw by raising the blade up 1" but
found out my blade leaves a curved cut at the top (is this what you use a dadoe
blade for, which I don't have yet?)
Do I need a jig to accomplish this, or is there a good trick to doing this?
Thanks for any help on this. My wife has been waiting patiently for me to finish
my custom frame project, which I'm all set and ready to glue. Just missing the
clamp!
Cheers,
-Win
Win wrote:
>
> Hello experts,
>
> I am new to woodworking and am trying to make a picture frame clamp, which calls
> for 4 identical jaws or L-blocks with a 90 degree interior angle. The blocks
> will each be cut from 3/4" stock 2"x2" square. I can either cut out the angles
> first or cut out the 4 square blocks followed by cutting the interior angles
> (which is preferred?)
>
> What's the best method and tool to use to create these 4 identical 90 degree
> L-shaped blocks? I guess what is more important is the exact 90 degree cut than
> the shape or sizes of the 4 pieces. The 2 cuts are 1" into the block.
>
> The tools I have at my disposal are: table saw, band saw, compound mitre saw,
> and a router. If using the table saw, I would prefer clean cuts where the table
> saw blade does not "run" or cut into the wood beyond the interior corner. I
> tried making multiple passes using my table saw by raising the blade up 1" but
> found out my blade leaves a curved cut at the top (is this what you use a dadoe
> blade for, which I don't have yet?)
>
> Do I need a jig to accomplish this, or is there a good trick to doing this?
>
> Thanks for any help on this. My wife has been waiting patiently for me to finish
> my custom frame project, which I'm all set and ready to glue. Just missing the
> clamp!
>
> Cheers,
>
> -Win
Cut your blocks to size. Mount a sacrificial face to your mitre guage,
clamp a stop block to it set at whatever width you want the legs to be,
raise the blade to your depth of cut and holding the blocks vertically
against sacrificial face make your cuts. Bingo-bang done.
Scott
--
An unkind remark is like a killing frost. No matter how much it warms
up later, the damage remains.
I made something similar for what others might call a pitiful cabinet
door clamping mechanism (Worked fine for me, though.)
I used 2" thick board so that I could more easily clamp from the sides
as well as the tops without my clamps fighting each other.
I took a 2" X 12" X 6' and measured in 11 1/2" inches to make a
square. Then I drew a concentric square (My high school geometry
teacher would love my bastardization of that term) that was 9 1/2" X 9
1/2". I set up my router with a straight edge guide and a 3/4"
straight bit and a 3/4" depth of cut (I was using these for 1" pine
boards). I roughty routed out the innerds of the inner square,
starting at the center and working my way out. After I had gotten a
good chunk cleared without getting too close to the edge, I clamped
down my stright edge router guide and carefully routed the inner
square's edge without crossing over the sides of the corner. I was
left with a rounded-corner square. I used a chisel to square off the
corner, double checked with a metal square. After that, it was three
cuts of the circular saw and I had four perfectly size corner clamp
fixtures.
After all of that, I decided I couldn't do without dust collection
anymore :)
Jay
To reply, replace junk with jay
I'd personally use the bandsaw, but my real reason for replying is to
give you some alternative ways of thinking about this.
It sounds like you want exact 90 degree corners on the blocks so they
will square your picture frame. If you measure diagonally across your
frame you can easily adjust your clamping pressure until the diagonal
dimensions are equal rather than relying on the clamping blocks. In
fact, you should measure the diagonals regardless of how you clamp the
frame. When the diagonals are equal the frame has to be square, or more
accurately the corners of the frame have to be 90 degrees. Therefore,
you don't need an exact 90 degree block when clamping. With that said,
I'd still want the blocks to be as close to 90 degrees as possible.
I don't understand why you're concerned about the tablesaw cut extended
past the corner. Raise your blade up as high as possible, use something
bigger than a 2x2 block and cut away until the cut on the top of the
block reaches your mark. Yes, the bottom of the block will have a cut
line beyond the corner, but big deal; it's only a clamping block. If
you use plywood for the block it'll be even less of an issue.
Another way of ensuring the picture frame is square would be to use an
L-shaped jig. Just screw two boards onto a piece of plywood. Be
careful and make sure you get the two boards exactly 90 degrees to each
other. Then just slide your picture frame into the corner and you know
the frame is square. Then you can clamp across the frame. I'd still
measure the diagonals as mentioned above to ensure it's square.
--
Larry C in Auburn WA
<snip of Win's clamping dilemma>
Win wrote...
> Hello experts,
ex - former
spurt - a drip under pressure
expert - a former drip under pressure
(G)
> I am new to woodworking and am trying to make a picture frame clamp,
> which calls for 4 identical jaws or L-blocks with a 90 degree interior
> angle. The blocks will each be cut from 3/4" stock 2"x2" square.
<snip>
> Do I need a jig to accomplish this, or is there a good trick to doing this?
Note that when you cut an L-block out of a solid piece of wood, the two
legs won't have equal strength if the cuts are perpendicular or parallel
with the grain. The side with short endgrain will be very weak. You would
be slightly better off to cut them at a 45-degree angle to the grain.
Secondly, instead of an L out of the corner, you can have even more
strength by cutting a V out of the side of a block, like in this nifty
ASCII diagram:
-----
| /
| /
| \
| \
-----
That interior angle should be 90 degrees -- so much for nifty ASCII
diagrams... BTW, the grain should be going up and down in that picture.
With this geometry the work can be clamped along the diagonals, using
only two clamps instead of four. The direct diagonal control also makes
it easier to square the frame.
Since the blocks are so small, all your cuts for the L's can be
accomplished safely and accurately using a crosscut sled on the tablesaw
with the blade tilted to 45 degrees. If you don't already have your
crosscut sled, now is the time to make it. You'll wonder how you ever got
along without one.
Cut your blocks 3" square or 3" long x 2" wide instead of 2"x2" because
the diagonal of a 2" square is almost 2-7/8". Clamp a stop block on the
crosscut sled fence about 2-7/8" from the kerf. Raise the blade so almost
2" projects above the sled (measure along the blade, not vertically).
Butt the first block against the stop, cut, flip the block and cut again.
Raise the blade just enough to finish the inside corner of the V, and
then cut the remaining blocks.
If you still really want to make L-shaped blocks, then the crosscut sled
is still the right tool for the job, but you may need to clamp the
workpiece to the sled fence to keep your fingers...safely away from the
blade.
If you don't have a crosscut sled and really don't want to make one (just
yet), then bolt a board to your miter gauge and use that.
Cheers!
Jim
Andy Dingley <[email protected]> wrote in message news:<[email protected]>...
> On 9 Dec 2003 22:52:28 -0800, [email protected] (Win) wrote:
>
> >I am new to woodworking and am trying to make a picture frame clamp,
>
> I used MDF, cut with a knife and fork (probably the bandsaw).
>
> The angle isn't critical. It's probably best to use about 92° anyway,
> just to get pressure right on the corner. This thing is a clamp, not a
> jig. You need to put the squareness in by some other means, not just
> squeezing the corners.
>
> My clamps are 2" disks, with a string groove around the edge, and a
> missing quadrant. Coat of wax stops the glue sticking. _Hot_ hide glue
> is good for framing, or Titebond - because both have good initial
> tack. Make a dozen - if you're doing frames, you're often doing
> several.
> .
Thank you everyone for your valuable input, tips, and ideas. This is all
really useful and have given me a new "angle" on how to look at this problem.
Regards,
-Win
On 9 Dec 2003 22:52:28 -0800, [email protected] (Win) wrote:
>I am new to woodworking and am trying to make a picture frame clamp,
I used MDF, cut with a knife and fork (probably the bandsaw).
The angle isn't critical. It's probably best to use about 92° anyway,
just to get pressure right on the corner. This thing is a clamp, not a
jig. You need to put the squareness in by some other means, not just
squeezing the corners.
My clamps are 2" disks, with a string groove around the edge, and a
missing quadrant. Coat of wax stops the glue sticking. _Hot_ hide glue
is good for framing, or Titebond - because both have good initial
tack. Make a dozen - if you're doing frames, you're often doing
several.
.
--
Die Gotterspammerung - Junkmail of the Gods