I quilted on an HQ16 for about 3 yrs. What a workhorse! Just recently I discovered a online tutorial about tensions for track mounted machines.
http://www.youtube.com/watch?v=Q1mRhcquZTM Jamie Wallen and Taking the stress out of longarm tensions. Good for any machine with a hopping foot. If this link does not work, PM and I will email it to you.