Woodworking jigs

[SAISAY]

I have just made up a circle/oval cutter for my router.
Instead of making it in wood I made it in perspex. No expansion/retraction from the humidity up here in the north.
When I go to0 Cairns I visit a perspex fabricator and collect all his scraps.
I also made a small right angle to gauge the blade to the worktable.
At the moment I am working on a mitre guide that will allow me to go beyond 45 degree angles.
Little Wolff

[munruben]

I like the idea of a mitre jig that will go past 45deg

[Pusser]

Photos/sketch please.

[joe greiner]

Good score on your scrap perspex source, LW. Never have enough of that stuff, do we?

Here's a circle cutter that doesn't impose a penalty on bit projection the way an auxiliary base plate does:

http://www.woodworkforums.ubeaut.com...ad.php?t=50372

Couldn't make a true oval with it, though. Perhaps an almost-oval with four centres like isometric circles are drawn.

Joe

[Rocker]

I like the idea of a mitre jig that will go past 45deg

Sorry for the highjack; but here is a jig that enables a mitre gauge to go beyond 45 degrees. A triangular jig with a 25 degree angle will enable mitres to be cut with angles between 20 and 45 degrees.

Rocker

[SAISAY]

Here is the first circle/oval jig that I made.<o></o>
Sorry I am not into techno speek.<o></o>
It is all made in Perspex and can be attached to the router as well as the jigsaw with a replacement base.<o></o>
First I cut 1 square piece in 6 mm Perspex and 8 pieces ¼ size of the large one..<o></o>
The 8 smaller pieces were glued together to make 4 pieces. These 4 pieces was cut on two sides at 10° on the bandsaw. I found that easier that routering them with a dovetail bit.<o></o>
I cut a rectangular piece 20 mm wide and also angled the long sides 10° then cut it into 4 pieces.<o></o>
The corner pieces were glued onto the larger piece using the small rectangular pieces as spacers. When the glue was dry I cut it into a circular piece.<o></o>
I cut 2 of the rectangular pieces 25mm long, drilled a hole in the centre and glued a steel pin into the hole.<o></o>
I cut a piece of Perspex the shape of the router base with a rectangular extension in one side and another 500 mm x 100 mm, then cut a 6 mm slot in the centre of this piece 25 mm from either end. Then I tapered it.<o></o>
To make the jig adjustable I drilled the centre out of 2 bedbolts, made 2 disks to sit on either side on the long piece and a wingnut on top to secure them in the slot.<o></o>
Instead of needing an extra long router bit, I made a piece of Perspex the same height as the distance from the workpiece to the bottom of the tongue. This got screwed to the rectangular extension on the base and to the tongue.<o></o>
I want to use this jig for round and oval picture frames so I can secure the jig to the workpiece with 2 countersunk screws in the jig.<o></o>
But, if I want to make, say, a tabletop and do not want screwholes in the centre, I secure the jig to the workpiece with doublesided carpet tape.<o></o>
To use the jig, it is placed on the workpiece and the hollowed out bedbolts placed on the pins.<o></o>
The router is placed on the shorter axis using the bolt closest to the router, the on the longer axis using the bolt furthest away from the router. No need for complicated measurements.<o></o>
I am working on another jig for smaller jobs but haven’t written up the destructions as yet.
Little Wolff
<o></o>Additional info:
In the other end of the slotted tongue I drilled a hole and inserted a rubber grommet the size of a pencil. By reversing the shorter and longer axis, I can draw perfect circles and ovals then cut them out on the bandsaw or scroll saw.
<o></o>

[Pusser]

Very nice work and good pics.

[munruben]

Thanks for that LW very interesting.