Finding Half Of Your Material Thickness!
Need to cut half way through your material to make a perfect rabbet joint? Here’s a simple method for finding the center.
Finding The Center Line
Lay your material next to the rabbet bit in your table mounted router. Raise the rabbet bit to what you think is center.
Making The Test Cut
Clamp a table fence in place over the bit, be sure to isolate the bearing so it is flush with the fence.
Note: Any time you mill material for a project you should be sure you have extra pieces to use for testing.
Run one corner of your test piece into the bit approximately 3/4”, flip the material over and run the same corner into the cutter again.
Results Of The Cut
Now look at the cut.
Three things can happen.
1) You can be right on and the two cuts meet exactly.
2) You can be too high and there will be a notch between the two cuts.
Solution: lower the bit half the distance of the notch.
3) You can be too low and there is a feather of material between the two cuts.
Solution: raise the bit half the size of the feather piece.
Why Is It Important?
When you make a rabbet, dado or groove it is best to make these cuts at half the thickness of your material.
First, it maintains the strength of the material with maximum gluing strength.
Second it is easier to compute the sizing of materials.
Finally, if it becomes a habit, you never have to remember what you did for the last cut because it is a standard that you follow.