Hey everyone, thanks for your interest and advice. The screw is two fold, it does secure the motor as well as provide a specific location for rubber bands. In the amount of time I've been using this machine I can't say that I've noticed any wobble from the cam. I will tell you that when using regular tubes and needles there is a bit of spitting due mostly to the way the cam is set up, so there's that. Again, I really did have the T Tech system in mind while creating this. Oh and just FYI the Hawk cartridges DO NOT WORK with this machine, they are too stiff and mess with the cam. The stroke length is about 4mm and is not adjustable. I found that for this cam set-up and using the T Tech system this length worked best. I will be posting videos a little later today for sure. There is noise from the motor/cam but I haven't found that it's helpful to the machine and artist relationship. Thanks again gang.