sewing machine ii 

parts of a sewing machine

1. bobbin winder- holds bobbin while putting thread on it

2. feed dog- moves fabric along under presser foot

3. hand wheel, allows the worker to lift and lower the needle by hand

4. needle clamp- holds needle in place

5. presser foot- holds fabric in place while stitching

6. presser foot lever- raises and lowers the presser foot

7. reverse button- allows the machine to perform backstitch

8. spool pin- holds the top thread

9. stitch length control-adjusts length of stitches

10. stitch pattern control- allows the selection of stitches

11. stop motion screw- when loosened it stops movement of the needle.

12. take up lever- allow upper thread to move and down

13. tension disc- controls tension of the thread

14. thread guide-directs thread from the spool pin to the needle

15. throat plate-covers are around feed dog

common machine faults

1. stitches not interlocking - needle inserted backwards

2. fabric not moving when stitching - fabric is too thick or beginning too close to edge

3. thread breaking - tension too tight or needle is incorrectly inserted

4. missing stitches - needle is bent or material is being pulled

5. loops on under side - loose top thread

6. loops on top side - loose bobbin thread or loose tension

7. fabric puckering - tension too tight or blunt needle

8. needle not moving - stop motion screw is not set for motion

9. needle breaking - loose presser foot or loose needle.