I have this exact machine, and had a lot of problems at first...Here are some links to threads I posted here, some have pics of things that helped me...One big thing is the free motion foot that came with the machine does not fit it...meaning it is totally off on size, one of my posts has a pic of what I mean...also I ended up ordering a 2nd bobbin case...that way I have one that I turn the screw on to tighten/loosen tension as needed..and the other one I leave at default (or the way it came...lol)..
Here are the links:
http://www.quiltingboard.com/main-f1...t-t152166.html
http://www.quiltingboard.com/main-f1...e-t152998.html
http://www.quiltingboard.com/main-f1...s-t153464.html
http://www.quiltingboard.com/main-f1...0-t153683.html
If you have any other questions, please feel free to pm me...it took me a while to get used to this machine, but now I do love it, especially for piecing, the pin feed really helps, and my fmq is getting better, but that is on me, NOT the machine..
. I did just buy the Janome Horizon 7700, mainly because my 1500 is straight stitch only...and I wanted as large a bed as I could afford on a domestic machine that has other stitches...haven't had a chance to try her out yet, tho...
Take care,
Kif