I have a problem with my scroll saw and I was wondering if any of you had the same problem. My scroll saw (Dewalt DW788) started knocking pretty bad. I found a solution on Rick Hutcheson's web site for the same description, but it didn't fix my problem. Since it was out of warranty, I decided to take a chance and open it to see if I could find the problem. What I found was that the "Con Rod Assembly" (the link between the motor and the rocker arm) was coming apart. The link was coming off of the bearing. The only reason it wasn't completely off, was that it was still attached to the rocker arm and actually cut into to rocker arm. I knocked it back in place and that fixed it, but it eventually works itself back off and I have to take it apart again. Sorry, it's a little long but I just wanted to know if anyone else found this problem.
I helped a friend with the same problem. The bolt came out of the arms that go to the front. We put some lock tight on the bolt before assembly, hopefully that will solve the problem.