Use Your Router as a Biscuit Joiner
Recently I picked up a biscuit cutter set from Dimar Canada (photo 1) and couldn’t wait to give it a try.
Many projects need some form of joint. Biscuits not only hold projects together but also make aligning your stock very easy. The kit as pictured is set up for standard #0, #10 and #20 biscuits. It comes with: a 1/4” or 1/2” shank; a 5/32” slot cutter; three sizes of bearings for the different size biscuits; and a sample of each biscuit.
To assemble the kit for routing, first you must choose the proper size bearing for the biscuit that you require. The large bearing is for the #0 biscuits, medium for #10 and small for #20.
Photo 2 shows how to assemble the cutter and bearing to the shaft. I used using the #10 biscuit bearing for my cuts.
Now that you have chucked up the cutter you must align it to the centre of your stock. Set up you router fence and isolate your bearing flush with the edge of your fence. Using a test piece, mark the centre of your board. Now align the centre of the carbide to the centre line that you have drawn (photo 3).
Test this set up by cutting a small groove into your stock (photo 4). Now flip the board over and check to see if the cutter goes into the slot from the other side (photo 5). If it doesn’t slide right into the slot, you are half the distance off. Either raise or lower your cutter half of the distance that you are off and run another test.
You are now ready to start cutting your biscuit slots. If you simply press your stock into the cutter you will find that the depth is right but the length is too short (photo 6). To compensate for this you must start your cut and then move your stock across the cutter to get the right length. The safest way to do this is to have stops on your fence (photo 7). Press your stock against the rear stop, pivot into the cutter and slide the board forward to the front stop. Now pivot off the cutter.
Guidelines to proper insertion of the Arbor into the Router Collet
Insert the Arbor all the way into the collet, and pull it back to the maximum so that it is more than the diameter of the Arbor. For example:
If you use 1/4” shank arbor, maximum pull back after shank has been fully inserted into collet, is 1/4”.
If you use 1/2” shank arbor, maximum pull back after shank has been fully inserted into collet, is 1/2”.
The DIMAR bit may be run at the max RPM of your router machine.
If you find that the groove produced is too wide for the biscuits provided, stop using the machine and check your router machine and router bit for run-out.
After extensive usage, the carbide tipped groover (fly cutter) will need to be resharpened by a qualified person.
Use only brand name, quality wood biscuits made of Beech wood. They will be stronger, consistent in thickness and will ensure proper assembly and ease of use.