Reply To: Cutting a circular depression – how to?
Welcome! / Forums / General Woodworking Discussions / Woodworking Methods and Techniques / Cutting a circular depression – how to? / Reply To: Cutting a circular depression – how to?
Hi Keith,
Done this using a power router, a circle guide, and a suitable guide bushing and router bit. I’ve had two problems with this method.
1. Finding a suitable circle guide. UJK offers a plastic board with pre-cut holes, but not beyond 85 mm in diameter. So I have used holesaws, as Ecky suggested, to cut out the guides from.
2. Some guide bushing dimensions (the more useful ones) are not available in metrics, but that can be overcome by cutting your own guides
One should be able to get to what you want by using:
a) holesaw set to 114 mm to cut the wider circle guide, a 24 mm guide bushing, a 6 mm cutting router bit to create the 96 mm wide hole
b) holesaw of 58 mm for the other circle guide, and same guide bushing and bit, to create the 40 mm hole
c) The circle guides need to be of same length and width, with the corners cut off from the one with the 58 mm hole
d) Centre the 58 mm piece on top of the 114 mm, and secure it with screws
e) Put the two on top of the workpiece, and clamp the free corners of the 114 mm to the workpiece
f) Rout the smaller hole in two goes of 5 mm each.
g) Unscrew the upper circle guide, which should leave the wider centred, and route the 5 mm depth.
The routing will produce loads of dust that will be blocked by the guides. Having an excavator attached to the router or a very frequently used vacuum cleaner, is more or less necessary.
Attached is a too didactic .pdf made for someone with no insight into woodworking.
https://www.axminster.co.uk/armeg-adjustable-hole-cutter-40-to-200mm-952812
An alternative method could perhaps be to laminate three pieces together: one being the bottom, the next the 40 mm hole one, and on top the 96 mm. The holes could probably be cut with a coping or fret saw.?
[attachment file=”600903″]
- This reply was modified 5 years, 1 month ago by Sven-Olof Jansson.
- This reply was modified 5 years, 1 month ago by Sven-Olof Jansson. Reason: Addition