The Sewing Place

Overlocker l/h needle thread problem


Overlocker l/h needle thread problem
« on: October 02, 2017, 16:39:26 PM »
I have a Brother 1034D which has previously worked fine (4 thread, 2 needle). I recently tried some stitch/seam variations as detailed in the manual, some of which meant I only needed one of the 2 needles threaded.

Having re-threaded I now find that the left-hand needle thread sometimes slips from behind the thread guide above the needles and round to the left. When this happens the thread simply creates a long loop along the fabric instead of stitches through the fabric.

I have checked the tension and re-threaded carefully twice.

Has anyone got any suggestions of how to cure this? Might it be worth changing the needles?


Re: Overlocker l/h needle thread problem
« Reply #1 on: October 02, 2017, 20:51:13 PM »
I presume you've threaded the needles in the correct order?  Is it left hand one first?  If so did you re-thread the other again after that one broke?  And does it do it with different thread?


Re: Overlocker l/h needle thread problem
« Reply #2 on: October 02, 2017, 21:38:26 PM »
Isn't the normal threading order from right to left - that is right to left as you face the machine? Not sure if that's the problem though.
'One should either be a work of art, or wear a work of art.' Oscar Wilde


Re: Overlocker l/h needle thread problem
« Reply #3 on: October 02, 2017, 22:21:07 PM »
I suspect that the thread hops out of the last thread guide after a stitch or two has skipped.

Starting over with two new needles is the best place to start.
When using two needles they should be the same size and type, 2 x 12s or 2 x 14s, sharps, stretch, or ELX705 etc.
(size 14 is the biggest size that can be used safely on a domestic overlocker unless adapted)

When the loopers go across the needles to pick up a loop of thread, the tolerances are small.  Even a very slightly bent needle can widen that gap just enough for the looper(s) to miss catching the loop which results in a skipped stitch.

Some other reasons for skipped stitches can be -

On a 1034D both needles are secured by one needle clamp screw.  It's common, and unfortunately very, very easy, for one needle to drop down ever so slightly whilst being tightened.  Both needles must be inserted and held firm as high into the sockets as is possible whilst the needle clamp screw is tightened.  Even 0.5mm or 1mm down and the looper will miss the point where the loop forms and the result is a skipped stitch.  A Two needle gadget is the easiest way to hold two needles and push them up at the same time whilst tightening the screw on a 1034D. 
You can make your own DIY two needle holder from a piece of card (use blunt needle to make the holes before switching them out for the new ones)

Very tightly woven synthetic fabric blunts a needle point quite quickly and as even a slightly blunt needle tries to push it's way through the fabric it can be deflected even a tiny amount but enough for the looper to miss the loop and result in a skipped stitch

Thicker fabrics or layers can cause a size 12 needle to deflect out of line even a little as they try to punch their way through the fibres.  It helps to use the correct size and type of needle for the fabric.  If size 14 needles seem to be struggling a bit too, then consider stitching very slowly. 

When stitch any fabric (woven or knit) with elastane content (lycra/spandex etc) the elastane tends to suck against the needle which puts drag on the thread and interferes with forming the thread loop so the looper doesn't pick it up and the result is a skipped stitch. 
It's best to use Stretch Needles or ELX705 needles if sewing anything with lycra content.

If you replace both needles with new ones and ensure they are both inserted right to the top of the socket and secured, the issue will probably disappear.
If it continues and different needle types don't resolve the matter then it may be a timing / alignment issue and that's a straight forward job for a technician to fix.


Re: Overlocker l/h needle thread problem
« Reply #4 on: October 03, 2017, 08:11:31 AM »
Thank you Morgan for taking the time to post such a comprehensive response - all makes sense and really helpful. I will put in new needles (carefully  :)) and hopefully that will fix the problem.


Re: Overlocker l/h needle thread problem
« Reply #5 on: October 03, 2017, 10:07:20 AM »
Needles changed and now working smoothly again - thanks!