|Project by vrice||posted 10-10-2015 06:59 PM||1114 views||6 times favorited||1 comment|
I’m starting a project needing a bunch of MDF circular plates (Stumpy's WS3000 Deluxe Sharpening System). So I needed a good circle cutting jig. Given I have researched this in the recent past, here on LJ and elsewhere, I took that knowledge (several good ones posted here on LJ) and the PARTS I HAD ON HAND and put together this jig in about 30 min. And it works great.
The idea I chose was to make use of a leftover piece of t-track as the adjustable element of the jig. I just cut a dado to hold the t-track, UPSIDE DOWN. This dado was positioned so the pivot point on the t-track is even with the cutting edge of the blade. This should prevent any binding when cutting. Then drilled a couple of holes to allow two T-slot bolts to pass thru. I used two, instead of one, to prevent this bar from pivoting, under the weight of the piece being cut, on the one bolt, plus I had plenty of bolts and knobs.
Then I trimmed this piece of t-track so one of the mounting holes was about one inch from one end. I took a wood screw that is just slightly too large for the hole and forced it in. This t-track aluminum easily submitted to the torque in driving the screw in. This made it quite tight. Just for good measure I put some CA glue under the screw head prior to driving it in. Then I ground down the screw tip so what was left was blunt and protruded about 1/2”. This requires a 3/16” hole for mounting the piece to cut.
Lastly I attached a piece of walnut I had previously milled for miter bar service and added a stop on the front edge that hits the front of the saw table as you slide the table into the blade.
That’s it. Works like a charm. This thing will cut circles from 3” Dia to 6’ Dia. The base reaches from the left edge of the bandsaw table to well pass the right edge. This serves two purposes. One guarantees the sawdust is forced to go out the dust collection port. Second easily allows me to clamp the left edge to the bandsaw table when cutting large circles. This prevents the whole thing from tipping under the weight of the piece being cut.
-- Vic Rice