Thanks, I was tempted to take you up on your offer, but after reading the manual it turned out to be several things, including the top part not threaded properly. Also wrong:

• Bobbin inserted backwards
• Bobbin tension too high
• Top thread was catching on the slit in the spool which you tuck the thread into when you're done - I need to get those long, slender machine spools instead of the hand-sewing spools.
• The dial to set the speed with which the cloth travels through the foot was set to zero, so the cloth was just sitting there

All of those things fixed, I have now successfully hemmed my first pair of cutoffs. Yee-ha!

You can still come over and meet the cats...