To the answer is in your travel. If you put the bit in the chuck and you measure its length it must be 1-1/2" or better to start. Now without the project piece there pull the handle down as far as you can with no stop detent holding you back. Should be a free fall. Now as you hold that there raise the table so that blade touches your sacrificial piece. Now let the arm back up Now measure the distance between the tip of the bit and the top of your sacrificial piece. If it measure and it should, over 1-1/2" means you have enough travel in the quill to do your operation. Now lower the table with the sacrificial piece still on it and insert your project piece between the bit and the table with as little space in between as possible. You are now good to go. I believe your travel is not allowing enough because you set the distance between the bit and project piece as too much before it enters the piece. Narrow that space up and it has to work. But if that bit is sliding up the chuck then you have other problems. But that is where your mystery is. Good luck.