The thickness of the vein is up to you. If it seems to thin, go over it with a thicker blade or, even a spiral blade. I would recommend you try it on some scrap wood before attempting on your work piece. You can always make it thicker, but you can never make it thinner. If you are careful, it’s easier to back the blade out while the saw is running. If the blade doesn’t want to back out, it’s ok to stop the saw and remove the blade. This is where a saw with a lifting top arm comes in handy. Just loosen the bottom blade clamp, and raise the arm.