The repairman said that the knife blade is "problematic" on the 2140. Some people don't worry to get them fixed at all, but I like to have it. Saves crawling under the middle of the quilt to cut the bobbin thread! However I did manage to embroider a design today without too much trouble, now that I recongize the knife will not cut the thread before it jumps to another section. Thanks to all for flowers and concern. V.