"MJ" wrote in message
...
Some of the responses have indicated
that I failed to give more detail.

Hopefully, this will help.

I want to build a grid of interlocking pieces
of plywood (3/4"). Each long piece in the grid
will be 4 feet long, the cross piece is also 4 feet.
The height of all the pieces is 4 inches. On top
of this, I'll put a sheet of 3/4 ply. I don't need to
make the top super flat as in a torsion box just
ok will do. The idea is that I'll be able knock
this down when I need to, which I expect
could happen over time. Want to end up
with a grid 4 feet by 4 feet.

I was thinking of a grid of three pieces in length and 5
cross pieces with one at each end.

The interlocking slots need to be all the same
depth, width and in the same spot on each corresponding
pieces (each cross piece needs to be identical, each
long piece the same).

I was thinking of a dado cut, but just not sure if
an 8" dado would cut that high, and to be sure of
consistently in the slots, I'd would have to gang
the pieces together. Seems to be a bit of
over engineering.

You only have to cut 2" deep. Stack and clamp all the length pieces & cut
slots. Do same for width. Precision relationship between slots is not
needed, as long as the pieces are stacked and clamped.

Seems like you would also want a bottom on the box to keep everything
together if you move it. Sounds like you would just arrange the crate on the
bottom, screw on the top, flip, and screw on the bottom.


I was thinking of making a template out of MDF or
ply. A router could be used to ride the template and
cut out the slots.

Are you thinking about running a router bit 2" deep into a slot? A bit
capable of that might cost as much as the BCT gizmo - maybe more. Cutting on
the face of the strips leaves you with the rounded end issue.

I'd use the dado. Simpler.


Someone suggested to me use of a jigsaw, but
I really want super straight cuts and each to
be the same. Not sure if the jigsaw is the right
tool for this job.

It's not.


I looked at the Kerfmaker - nice tool, but am
barely able to afford to buy MDF these days
then another tool. Besides, it looks like
it's better for a tablesaw, then a router.

But you do have a table saw, right? For the dado set?

BCT stuff is very well made, but obscenely expensive.


Hope that helps.

MJ



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National Socialism showed what can happen when very ordinary people get
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Anthony Burgess