I have a Janome 1600 on the Little Gracie II - Your statement about the needle not having a flat side really throws me for a loop because the needles that came with my machine do have the flat side. These are Organ brand which are HLx5 and according to articles I have read, this needle is made for the Janome 1600P.
I haven't had the machine very long and have not tried any other brand of needle yet, but even the manual shows it uses flat sided needles.
stitchfancy
Originally Posted by rhondakp
I have the Janome 1600 on a Grace Pro frame. When I have problems with the top thread breaking it has always been that the needle isn't in the correct position. Since the needles don't have a flat side to guide you on position, sometimes you have to play around with the needle. When looking at your machine on the frame, the needle would usually be in the 6 o'clock position. Sometimes you need to move it slightly to the 5:30 position. I use Organ sharp needles all the time and the only thread I have had problems with was the water soluble. Hope this helps.