A quick built from scrap basic router table to cut discs of a single size.
Messy as it has no facility for dust collection and not overly safe as it has no guards but it works.
Step 1: First Moves
First I checked I had a cutter that would pass through one section of furniture board (particle/ chip board with smooth plastic facing) and over half way through a second. I then removed the plastic sole plate from the router and used it as a template to mark the position of the needed holes on a piece of furniture board. In this case a salvaged shelf. drilled clearance holes for the mounting screws and counter sink them.
Step 2: Bolt It Together
Using long countersunk machine screws bolt the router firmly to the base.These have to match the sole plate holes of the router in my case they are M4
I had intended cutting the bit hole with a hole saw but couldn't find it. so I fitted a 3/4" bit in the router before I bolted it down. It was at this point I discovered the 4 mounting holes were not symmetrical placed. A minor inconvenience this time but it placed the power switch less convenient than I'd have liked.
Step 3: Bore the Cutter Hole
Remember I fitted a 3/4 bit before I bolted it down. that was because without a hole in the board for the cutter there is no way to change them. With the board supported so the cutter won't dig into anything turn on the router and use the plunge facility to bore the cutter hole.
Step 4: Drill the Axel Hole.
At this point the router is unplugged. I changed the 3/4" bit for a 1/2" one and locked the plunge mechanism at its maximum depth. knowing I need 8" discs I measured 4" from the tip of the cutter and drilled a 6mm hole for my axle bolt. I just happened to have a long M6 bolt, large wing nut and a wide washer to spread the load laying around.
Step 5: Operation
I firmly clamped the board to my old work bench. Unfortunately the jaws don't open wide enough to accommodate the router body the way I orientated it. I drilled a 6mm hole in the board I was cutting my disc from just over 4" from the edges. then with the router running I fed the board into the cutter until the axle holes lined up. I switched off the router bolted down the board I was cutting to the table top. switched the router on and rotated the board into the cutter, the cutter wasn't actually long enough to cut the board in one pass so I turned it over and re did the cut. Repeat on more boards until you have all the perfectly circular discs you need with a central axle hole. If you took enough care in your marking and drilling they should be exactly the right diameter to.
Step 6: Make the Instuctabtle
Feeling quite happy with my work I thought. Mmmm perhaps someone else could use this Its not a new idea and it has probably been done and documented better but just in case as I was taking it apart to put away I staged photos of the construction process.