With 18mm plywood I made a circular saw track guide jig. fortunately it works perfectly. I'm pleased with that. But 18mm plywood was too thick to cut thicker boards. It sacrified too much thickness. So I re-made a sled with 12mm. I recommend you make the jig with thinner or same wood of 12mm. This video is original and hasn't been changed with modified one. Sorry about that and please forgive me.
Anyway I would like you to enjoy watching. Thanks a lot.