Will go through the guidebook to troubleshoot but are there general rules regarding sewing ripstop we should start with?  We've gone thru various upper thread tensions - getting closer to a good zigzag stitch but it's still skipping some stitches and puckering. Works fine with other fabrics.  Should we experiment with the presser foot tension knob? 

1. Make sure the needle is in correctly. The scarf must be directly to the right (flat area above the eye of the needle).

2. Make sure the needle is all the way up. Look through the view hole to be sure it is topped out.

3. Use V-30 or V-46 thread.

4. Use basting tape in the seam for testing. It will greatly help with the puckering. Reduce tension until the knot is visible on the bottom and then slowly tighten until the knot is just buried.

5. Reduce presser foot tension until it is almost completely off. In fact it will come loose and fly off if you are not careful. When it does come off just thread it back in about three turns.

We tried everything suggested but the puckering was always a problem.  We are going to use an old home machine - seems to handle the ripstop fabric just fine.  The Ultrafeed is great for heavier Dacron projects though.

Thanks!