As you know, puzzle pieces have complicated checkouts. Making these checkouts accurately and safely, we need a jig called a sled.
Here is a sled that Juno made and the next picture is a dado* cutter.
As the next picture shows, if there is no cover the dado cutter can be touched easily and it's really dangerous.
The next safety measure to show you is a stopper. (see the blue circle in the picture)
In case of pushing the sled too far back, even if there is the safety cover, the dado cutter comes out and there's a possibility to touch it by accident. This board on the back end of the table saw acts as a stopper and you may not push the sled too far. Another point is to keep the sled moving the distance it needs. If it can cut the pieces as they are needed, it is not necessary to push the sled a lot further.
The next attachment is the panel which is fixed on the back end of the sled (see the green circle in the picture). As I wrote, the dado cutter turns at high speed and it scatters sawdust and debris. It is not often but sometimes the tip of the blade breaks and small metal piece might fly toward you at high speed. This panel prevents these things from flying.
The last trick to introduce is this small rectangular block with a handle.
This block is for holding puzzle pieces stably and also works to prevent touching the blade.
As you see, the dado cutter is just underneath these puzzle pieces. The blade is so close to fingers and it is extremely dangerous to hold these pieces by hand, therefore it is turned by using the holding block.
Juno makes holding blocks in conformity to a thing to make.
See you next time!
Yukari
*Dado: A kind of wide checkout. It is commonly used by burr puzzles.