(4) Pairs of 48"
(4) Pairs of 36"
(4) Pairs of 24"
That should do.
Here's a quick explanation of how they work. You put an F-style clamp on each end with the cambers facing each other. By clamping the far end until the wood touches, you'll be flattening out the curves in each caul, thus applying even pressure along the length of the cauls, thus keeping the boards you are clamping flush to one another.
Sorry for the lack of photos of the build process, but it's pretty straightforward.
- Buy 8/4 Lumber, preferably something stiff. Maple or Oak are good candidates.
- Rip to 1-3/4" width
- Cut to length
- Draw an arc on one of each length, according to the specs on Lee Valley's site
- Draw lines every 6" down the length of the board
- Use the jointer to work your way down to the curve, using those 6" lines as reference points to maintain symmetry
- Trace the curve you just made onto the other boards, repeat steps 5 & 6
- When the curves are done, run a dado down the middle of the flat side opposite the arc (just to make it easier for the router)
- Then run the T-Slot at the router according to the specs on Lee Valley's site
- Use a card scraper and sandpaper to smooth everything out
- Drill a through-hole at one end and run some paracord through it for a hang loop
- Wax 'em up
- Find somewhere to hang 'em
$358 for (4) Pairs of 48"
$278 for (4) Pairs of 36"
$190 for (4) Pairs of 24"
= $826 total
I spent $150 for the lumber and $47 for a Whiteside T-Slot router bit.
= $197 total + 2 or 3 afternoons
More than I intended on spending, but these will come in quite handy during table top glue-ups of any size.