hello I'm Simon welcome to my workshop, and in this video I'm going to be making a circle
cutting jig for my router table.
I've been cutting a lot of circles lately so decided it has high time to build a proper
jig.
Now most circle cutting jigs I've seen are for hand held routers, the work piece is clamped
and the router moves around the workpiece in a circle. But with a router table the router
is fixed, so the jig needs to move the workpiece rather than the tool, and I found a simple
design so thought I'd give it a go.
The jig uses a single piece of 18mm ply for the track and a small piece of hard wood for
the carriage, the dimensions are arbitrary but the track wants to be about 1 and a half
to 2 inches wide and a little longer the the maximum radius you think you will cut.
I cut this out on my MFT style workbench using my track saw and speed square for support.
... Let me explain what I'm doing here, I want to route a grove down the centre of this
piece of wood. Ive use my router depth gauge to set the blade so the centre of the blade
should be where the centre of the wood is, i need to route this, probably going to do
it 9mm maybe 10 mm deep, and I've set the router blade at the moment to just under 1mm
and ill go up in 1mm increments so i don't put to much stress on the blade, there nowhere
for the dust to go other than down, so that's all set up lets get routing.
I made some marks on the router table so I'd know where to start and stop and took a few
passes altering the depth as I went.
I then drilled a pilot hole the same size of the router bit, fitted this over the bit
on the router table and cut a slot the length of the groove I'd previously cut.
To complete the Track, I raised the bit and cut a groove in the end.
I then found a piece of hardwood for the carriage and roughly cut it to size using my band saw,
then I fitted an M6 threaded insert into it.
I then trimmed the end of the ferrule flush with the wood.
and using my belt sander I sanded the part and rounded off the ends.
I then drilled a 2.5mm hole in the carriage, this will hold the pin that secures the jig
to the workpiece.
And to make the pin I used a cheap Chinese drill bit, these drill bits seduced me with
their price but they really are useless, as well as cutting them easily with the hacksaw
they also bend, something I've never seen a drill bit do before.
The carriage now complete, all that is left is to make the knob, I'm using one I salvaged
from an old black and decker worktop router table.
And that is basically it. To cut a circle you first drill a 2.5mm hole where you want
the centre to be.
now, in beam compass mode you can draw your circle, and rough cut it on the band saw,
finally finishing it on the router table.
The router bit is a flush cut bit, so has a bearing on the top, this fits in the notch
we cut out of the jig, it's then just a matter of turning the workpiece, note I started turning
it the wrong way before correcting myself. even so I got a perfect circle at the exact
radius I needed for my next project, to find out what I'm making remember to subscribe.
...well i hope you enjoyed this video as much as i enjoyed making it, if you did then please
leave a thumbs up and I'd love it if you subscribed, and as always if you've got any questions
just leave them in the comments and ill answer them as soon as possible. Well that's it for
now, thanks for watching and I'll see you in my next video.