I got my first scroll saw last night. It was the ridgid model ss1650. I like all it s features and it does not appear to vibrate to badly. I do have some questions? When I first turn it on it is slow to start moving at any speed, is this normal? The biggest concern though is that when it running it sound like it is throwing a rod (best way i can describe it. I checked the underside and it appears to be clear of any items to hit. The noise sound like it coming from the motor housing. Any idea's ?