Pattern cutting on a table saw is an easy and fast way to produce lots of identical parts. I’ve used this technique to make parts for everything from bird houses to Adirondack chairs. Get started by making the fence.
Make the pattern fence using a vertical piece that is 1-3/4” wide and a horizontal piece that’s 3” wide, glue and screwed together. I used 1/2” mdf, but 3/4” thick material would work as well. They need to be nearly as long as your table saw fence.
Choose the right blade. In most cases, when pattern cutting, you’ll do a little ripping and a little cross cutting. For that reason I prefer a 40-tooth ATB (alternate top bevel) blade. It does both types of cuts well.
Set the blade height. With the saw unplugged, set the height of the blade so the bottom of the gullet (the valley between the teeth) is even with the top of the material you’ll be cutting.
Set up the fence by clamping it to your table saw fence high enough to clear the top of the blade. Set its left/right position so the edge of the fence projects slightly past the face of the blade. This is easier to feel than it is to see. The more the fence projects past the blade, the more waste you’ll have outside your pattern.
Fasten the pattern to your material using double-faced tape (see Sources). The material may need to be rough cut close to the pattern size so that it can slip under the horizontal part of the shop-made fence without hitting the table saw fence. The pattern has to be made from material thick enough to allow the pattern to ride on the edge of the pattern fence and not slip under it. 1/2” thick pattern material should work, but double check against your setup.
Make the first cut by allowing the pattern to ride against the edge of the pattern fence. Use a push pad to maintain a good grip and keep the pattern and fence edges in contact.
Complete the cuts, following the pattern edges as required.
Watch for kick back potential. The offcuts can get caught under the pattern fence, between the blade and the table saw fence. Stop, unplug the saw and use a dowel or piece of scrap to push the offcuts all the way through and clear of the blade.
The completed piece will be slightly larger than the pattern. How slightly depends on how you position the pattern fence relative to the blade. The more it projects past the blade, the bigger “slightly” becomes.
At this point you can flush trim the material to the pattern using a flush trim router bit. Or, when you make the pattern, take the offset into account and allow the table saw cut to be your final cut.
Double sided tape
All Woodworking Articles, One Great Tip