Step 1: Go shopping!
1 pine strip (1.8m long) and 22mm x 22mm.
4 x bolts (70mm x 6mm) with their accompaning nuts.
a drill (with 6mm bit).
mesh ( i've sourced mine from screenprinting suppliers and is a 55 mesh count)
Step 2: Cutting and drilling
i've used 2 x 45mm pieces and 2 x 35mm pieces (this is just my preferred measurements)
each piece will have a hole drilled through the side, and on the other end, into the middle.
the depth of the middle hole should be about 20mm
Step 3: The lay-out
in other words, the corners will be overlapping, not square.
this is best described by looking at the diagram.
each corner is connected by the bolt, then nut, and glued into the hole.
at this stage the nut will be tightened away from the glued hole.
allow to dry
Step 4: Mind the gap
then tap the ends of the pine strip closer so that the bolts are protruding on the outside.
now your frame should be square and the corners seperated by the nuts.
Step 5: Attaching the mesh screen
its not necessary to try pull it tight while attaching.
the nuts will do that for you later.
use wood glue to ensure an even stronger fit.
allow to dry.
nearly done! maybe time for a cold beer, never drink beer and handle a drill at the same time, instructable on how to stem blood flow from a drill wound at a later stage