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Old 07-06-2007, 02:43 PM   #5
bobj3
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Hi Rich

The bearing on router bits,,, it's just fence so to speak, that said, make a fence like the one below, this will work a guard and let do your concave curve pass easy and safe...just ease into the bit and once your on push your stock around the guide...the guide will act like a start pin and let you get on the bit
safe and let stay ,hardwood be best for the guide/jig but it can be plywood or MDF....

The bits below also work great for what you want to do...
Making toys

Train Track Router Bits
http://www.mlcswoodworking.com/shops...ack_bit_anchor


=================


Quote:
Originally Posted by imrichb
I'm trying to cut a semi-circular groove along the edge of a piece, pictured in the attached. I can do this easily along a straight edge using my router table and a round nose bit. The challenge is that I'd like to do this along an edge that is curved (and to make it more challenging, a concave curve).

Any advice? I had thought maybe I could use a 3/4" ball cutter bit with a 1/2" bearing around the shank to guide it along the edge of the workpiece, but unfortunately I can only find a ball cutter bit of that size with a 1/2" shank, meaning that I can't put a bearing around it.

(In case you're curious, this is for a children's toy I am working on. The groove will essentially form a track for a marble to run down.)

Thanks in advance!

Rich
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groove-edge-curved-piece-bit-guard.jpg  
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Last edited by bobj3; 07-06-2007 at 03:08 PM.
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