Resolving Stitch Issues

The following issues are commonly seen and discussed across the internet and social media.  For the sake of this reference material, we will assume that the customer has experience with setting the proper tension.  There are many videos that discuss this so we will not be covering it here.  Everyone has a bad day and can forget to check these common causes.

1. Skipped Stitches - Needle makes a whole but does not make a stitch.
2. Long Stitches - Needle does not go down when expected, leaving no whole and a long stitch.
3. Looping on the Bottom - Almost always the top thread being outside of the tension disks.
4. Shredding/Breaking Thread - Sharp edges in the thread path, bad thread path, or wrong needle size for thread.
5. Inconsistent Tension - An interesting topic.
6. Jagged Stitches - noticed going front to rear in vertical line.

THIS IS NOT AN OFFICIAL HANDI QUILTER DOCUMENT.  All information contained in this document are the responsibility of MK Quilts.  Recommendations for changes should be emailed to info@mkquilts.com.

SKIPPED STITCHES - Won't Pickup the bobbin thread

1. Have you replaced the needle?
   The "every quilt deserves a new needle" is specious.  (Look it up.)  That being said, it is a good place to start when when troubleshooting.  Make sure the needle is the correct type and gauge for the thread you are using.  The groove in the needle needs to fit the thread.  https://www.superiorthreads.com/education/thread-weight
2. Is the needle in backwards?  Groove should be to the front, concave eye to the rear.
   Everyone will do this at least once.  Avoid the embarrassment.  Triple check by running your finger nail down the front groove of the needle.
3. Is the needle inserted straight and all the way to the top in the needle bar?
   If the needle is too long due to not being fully inserted in the needle bar, it will throw off the timing.
4. Is it skipping a lot, or only occasionally in one direction?
   Many machines will get 'a little out of time' and only skip in certain situations such as going right to left and basting.  If you have cleaned the hook and basket by taking off your needle plate and checked everything else, you are likely looking at a timing issue. 
5. In very old machines, the needle bar brass bearings can wear.  These can only be replaced at the factory.  This should be your last concern as we are normally talking about machines that are over 80 million stitches.  An un-serviced machine may see this sooner due to a lack of oil.
6. Did you have an "unfortunate incident" like a needle breaking?
   Resetting the timing on a machine is not a warranty issue.  When set properly, the timing on a machine will not change without a physical event happening to jar the Hook & Basket so that is moves on the shaft.  Watch the MK Quilts 'Checking the Timing' video and save up to purchase the timing tools.  Each service manual has good photos and instructions on how to do timing.  It does take practice and skill, but does not require opening the machine.
7. Is the hopping/presser bar still moving and holding the fabric down as the needle comes up?
   One common problem occurs when a hopping foot gets caught under a seam and it gets pulled from the internal mechanism.  It is spring loaded and should snap down without banging hard on the needle plate.  If the hopping foot is not articulating as expected, it likely needs to be popped back into place by opening the machine.  This is best done by a technician, but could be done with remote technical assistance.
8. Is your hopping/presser foot at the right height?
   Many experienced longarmers will raise their hopping foot on very thick quilts and then forget to reset them.  The hopping foot is spring loaded and almost never needs to be adjusted in this way.  The hopping foot should barely touch the needle plate when the needle is in its lowest position.  Anything more than a business card worth of space could lead to stitch issues.
9. Time to check the timing and Needle bar height.

Long Stitches - no hole

Long Stitches are almost always due to the encoders and stitch regulation.  Please review the Resolving Machine Issues guide for troubleshooting this issue.

Needle Breaks

Needles rarely break.  When they do, you were likely due to an unfortunate event.  You may want to remove your needle plate and make sure the needle did not strike the Hook & Basket causing any sharp edges.  If part of the needle jammed into the H&B, the machine is likely going to be out of time.  So removing and inspecting the H&B is recommended.  (This requires timing to be performed.)
These are common causes of needle breakes...

1. Needle strike to ruler, pin, scissors, or other foreign object.
2. Striking needle plate due to bumping needle with ruler while stitching.
3. Needle not inserted to the top of the needle bar or not tightened leading to it falling off into the H&B.
4. Incorrect needle system for machine.  HQ machines use a 134 needle.
5. Timing is out due to a previous incident, causing needle to strike H&B.
6. Basket (part of H&B) spinning due to stop finger out of position.  (After timing/maintenance.)

Thread Shredding, Fraying or Breaking

1. Ask yourself what has changed.  Quilt fabric, batting, thread, pattern, tension...   If there was not an incident to knock out timing, it is likely something that changed or dirt on the hook & basket. 
2. Inspect all thread guides in upper threading area, stirrup, edge of ring light if you have an Avante, needle bar thread guide, needle plate hole, and the holes in any of the plastic specialty presser feet for nicks or grooves that have been created by thread friction.
3. Check that the take-up spring on the tension mechanism is NOT hitting the stirrup - bent bar tread guide.  Take up springs can deform and strike the bar, breaking thread and causing tension issues. 
4. Incorrect size needle (or needle system) for the thread being used (you may need to go to next size larger); needle inserted incorrectly.  Have you changed thread or needle type?
5. Look for burr on the needle and/or the hook (especially if you have had an “unfortunate incident”.)
6. Inspect and remove any lint in the thread guides, tension discs, bobbin case/spring. 
7. Upper thread tension too tight.
8. Old or poor quality thread.   
9. Poor quality fabric or fabric stretched too tightly.
10. Put on a new sandwich of fabric and batting.  If the shredding persists, swap out the thread on top an bottom for a different spool.  Some lots of thread can be defective.
11. Have your machine re-timed even if it does not look out of time, cleaning the Hook & Basket very well while it is out of the machine.  This has resolved several instances of random shredding without finding another cause.
12. Replace the Hook and Basket.  This is an expendable item that is not covered under warranty.  Keeping it well oiled is necessary for reducing wear.  However, excess oil will weaken thread and lead to breakage.  Stitch off slowly in the batting after oiling until oil is distributed.

Tension Issues

**ALWAYS SET YOUR BOBBIN TENSION FIRST

1. Top thread lays flat on fabric
   1. Upper tension dial too tight
   2. Check for lint in upper tension discs, bobbin tension spring, and under bobbin backlash spring
   3. Is the machine threaded incorrectly
   4. Poorly wound bobbin
   5. Thread not in bobbin tension spring
   6. Bobbin tension not set correctly
2.  Bottom Thread Lays Flat
   1.  Upper thread tension is too loose
   2. Lint in bobbin tension spring
   3. Poorly wound bobbin
   4. Thread not in bobbin tension spring
   5. Bobbin tension not set correctly
3.  Bottom Loops
   1. Top thread tension set too loose
   2. Thread is not flossed in top tension discs
   3. Machine not threaded correctly
   4. Burr on hook and basket - clean and inspect
4.  Inconsistent Tension
   1.  Poorly wound bobbin:  this can be the result of winding too fast.  The thread can stretch and the tension is so tight that it collapses the inner core of the bobbin and it becomes concave on the top of the bobbin.  This bobbin is no longer a good bobbin and needs to be discarded.  A bobbin can have a “sloppy” wind if it jumps out of the tension discs, the tension is too loose, or if the wind is uneven because the pigtail needs to be adjusted.  (See your bobbin winder user manual for more detailed information).
   2. Bobbin case worn out and has a weak spring→replace with new bobbin case or spring.
   3. Backlashing: Be sure spring is inserted into bobbin case correctly with cone elevation facing up and notches of spring seated properly.  Do not flatten spring.  When the bobbin is in the bobbin case it should sit a little higher than the edge of the bobbin case and you will be able to depress it slightly with your finger.
   4. Tension Assembly: Check to be sure there is no thread or debris caught in the tension discs.  Check to be sure that the tensioner is functional by increasing and decreasing the amount of tension and watching the numbers on your screen change accordingly.
   5. Thread guides shredding, but not breaking thread which leads to a link obstruction.  Floss all thread guides and examine for ANY grooves or rough surfaces.
   6. Check the “levelness”, both vertically and horizontally, of your table.

Jagged Stitches

After an extensive investigation with Handi Quilter and MK Quilts, we believe that a front to back vertical stitch will look jagged due to the thread alternating which side of the needle it is pulling the thread from.  Simply turn the needle to a 5:30 position so that the thread routinely goes down the same side of the needle on front to back vertical stitches.

Details
Testing was done varying these parameters...

1. Top and bottom tension
2. Fabric type
3. Fabric angle 
4. Batting thickness
5. Needle bar assembly alignment
6. Needle type
7. Needle angle
8. Stitches per Inch

Our conclusion was that if a machine is more perfectly aligned than other machines, the thread will randomly pass down the right or left side of the needle as it pulls thread when stitching a straight vertical stitch toward the back.  The top thread is normally threaded from the front of the needle, so if the previous stitch is in front of the needle the thread will pull around the needle on one side or the other.  The thread enters the next stitch hole at a different angle leading to the appearance of the jagged stitch.  Thread tension and type can affect this stitch, but we found that only the angling of the needle assures a perfect front to back vertical stitch.