Originally Posted by
minibarn
I find that my 15-91 does not sew through thick layers well at all. It will stop altogether and I have to all but force it too go, sometimes it will most times it won't.
I wonder if it would improve with a bit of cleaning, oiling, and greasing? Maybe a motor service? There are stories of how the basic 15 will stitch through tin cans with out hesitating. I don't know the potted motor well at all, but there are a few here who swear it's the best on their 15 or 201, and is one of those models that should stand up to anything you can fit under the presser foot.