>First: Verify your needle is a 15x1, or if your using a Singer needle a 2020. Also check the original needle for type. Something caused those burrs and it could have been hitting the bobbin case too.
>Second: Make sure the grove the needle fits in is clean of gunk and debris so you can get the needle all the way up.
>Third: Make sure the bobbin case is all the way in correctly. The finger must point up and be inserted between the two square parts on the underside of the needle plate.
>Forth: If all of these things don't show anything then perhaps the needle bar is set too low or bent. At that point you might need the help of a sewing machine mechanic.
When you do all this turn the hand wheel by hand and watch what's happening. Don't power it up until you're sure you've got this sorted out.
Joe