Common Reasons for Sewing & Embroidery Machines to Malfunction
Needle Breaks
Needle is inserted incorrectly
Needle clamp screw is loose
Bent needle being used
Upper or lower threading is not correct
Upper thread tension is set too tight/high
Needle and/or thread for fabric being sewn is not correct
Material pulled and/or moved excessively during sewing
Incorrect spool cap
Wrong combination Needle/Thread/Material used
Wrong presser foot being used for application
Bobbin Case (Inner Rotary Hook) not inserted correctly
Loops on top or bottom of fabric during sewing
Upper or lower thread tension not set correctly
Upper or lower threading is not correct
Incorrect bobbin being used
Bobbin is not inserted properly
Threading is out of tension
Missed take up lever when threading
Upper thread breaks
Upper threading is not correct
Upper thread tension is set too high/tight
Upper thread is too large for the needle eye
Needle is inserted incorrectly
Incorrect spool cap
Shuttle Hook/Inner Rotary is not installed correctly
Incorrect bobbin being used
Lower thread breaks
Lower thread could be entangled in shuttle
Lower thread tension is set to high/tight
Lower threading is not correct
Shuttle Hook/Inner Rotary is not installed correctly
Incorrect bobbin being used
Burns on the needle plate
Skips stitches
Needle is not sharp and/or straight
Needle is inserted incorrectly
Needle and/or thread for fabric being sewn is not correct
Upper or lower threading is not correct
Machine runs slow and/or noisy
Machine may require cleaning or lubrication
Lint and/or debris may be caught in shuttle and/or feed dog assemblies.
Upper or lower threading is not correct
Shuttle Hook/Inner Rotary Hook is not installed correctly
Belt is too tight or too loose
Material tends to Pucker during Sewing/ Embroidering
Upper or lower thread tension is set too high/tight. (Tight tensions, Adjust for garment and thread type. Polyester thread will stretch during sewing especially if tensions are too tight. After the stitching is complete, the thread returns to its original length puckering the garment.)
Upper threading is not correct
Thread may be caught or is catching on something
Lower thread is unevenly wound on bobbin
Incorrect bobbin being used
Improper hooping tensions. (Hoop sturdy, woven fabrics tightly: Loose hooping will cause the fabric to bunch up under the stitching. Hoop soft knits tautly using a stable backing: over stretching will cause it to look puckered when the hoop is removed.)
Design densities are too heavy. (Too many stitches in an area pull fabric causing it to look puckered. Decrease the design slightly (5%-10%)
Dull needle. (Dull needles push the fabric down instead of pushing between or piercing the weave. Replace needle.)
Column stitches are too long. (Re-digitize as fill stitching or multiple rows of column stitching.
Design Out Of Register
Loose hooping. (Re-hoop being careful not to pull stetch fabric out of shape in an attempt to hoop tightly)
Unstable fabric. (Use more or heavier backing. For more stability use an adhesive spray to fix backing to garment.)
Design digitized incorrectly. (The design may need more pull compensation or underlay to accommodate stretchy or high – napped fabrics.)
Needle Cuts or Holes in Garments
Dull Needle. (Replace needle. Dull needles have a difficult time getting through the garment causing some fabrics to tear.)
Wrong needle point type. (Sharp and round point needles can cut some knits. Use ball point.
Delicate fabric. (The simple penetration of the needle will cut some delicate fabrics. Soften the impact by using topping.)
Thread Breaks
Improper threading. (Re-thread machine assuring thread goes through all guides order.
Too much or incorrect adhesive spray. (Use only adhesives designed for embroidery applications. Excessive adhesive build-up on needles causes them to drag and break thread. Replace needle after using adhesive spray.
Stitch length too short. (Slowing down machine helps. Increase stitch length)
Stitching over stitching. (Reduce density in the overlay. Avoid more than 2 layer of thread)
Old dry thread, (Replace thread. Thread becomes brittle with age and prolonged exposure to light, air, and heat. Store thread in cool dark place.
Excessive Friction (Increased friction between the needle and thick or abrasive fabrics or backing with excessive chemical coatings. Reduce machine speed.)