|Forum topic by mileskimball||posted 04-11-2013 06:29 PM||664 views||0 times favorited||9 replies|
04-11-2013 06:29 PM
I’m trying to mill some pieces of tight-grained cedar for parts of a traditional paper-making mold, and so far I’m stumped at getting consistent results.
Here’s what I’m aiming at:
The part is a support bar that holds up the wire mesh – there will be fifteen of them, and they need to be really consistent. As you can see, it has an airfoil shape (thin edge up), but with a dowel-tenon end that inserts into a hole drilled in the side of the mold. The whole mold will look like this:
In a row like this, the airfoil shapes create a venturi to suck the water out of the bottom of the mold (pretty smart for something designed 500 years ago!)
I’ve been able to mill the airfoil shape with a combination of a router and a table saw – I use a beading bit on a 7/8” thick plank to form a bead, then rip the plank at an angle to form first one side, then the other side of the airfoil.
But forming the dowel tenon has been a challenge. I’ve tried cross-cutting on the TS to form the shoulder and create a flat bottom of the dowel, then just whittling to get it round – works, but slow and inconsistent. I’ve also tried a hollow auger – it was too easy to snap the dowel off, the cedar being pretty brittle. Same thing using a plug cutter. A log-style tenon cutter wouldn’t work—they make curved shoulders, and I need the shoulders to be flat.