Brother LS-1520 sewing machine.Bottom bobbin thread gets caught and has 3 threads coming up! Driver is pitted?

Question

I have been trying to fix my brother LS-1520 on and off for over a year. I have cleaned, cleaned, and cleaned the machine. It's clean, for sure! I have been looking for replacement parts without any luck. I know the driver is pitted from a bent needle that wasn't my fault. The clear disc that sits under the top thread spool was not completely glued onto the machine when it was new. The thread got caught between that clear disc and the top of the machine and bent the needle, causing it to hit the shuttle hook and pit the driver, before finally breaking into 3-4 pieces and hitting me in the face. I was unhurt, amazingly, and thankfully. I was new to a sewing machine at that time, but I've gotten over my fears and sew regularly. This LS-1520 is my back-up machine. It doesn't help to have a back-up that doesn't work. I can wind bobbins on it.

The problem is that THREE threads come out of the bobbin area. The excess loop of thread, created by the two extra threads) catches the fabric and causes it to quit moving. I get a huge ball of thread on the back of the fabric and a hole in the fabric. I have to cut the thread and fabric out of the feed dogs. It gets bad really fast.

I have been told my shuttle race is scratched. I think the problem lies between the pitted driver and maybe it is out of time due to needle hitting the shuttle hook when it was bent.

I have done many searches on the interent to find a part/parts for this machine and on eBay with no luck. I am in a very rural area with no repair technicians that I'm aware of. I think it would be wise to fix the machine myself or just buy a new low-cost one.

Where can I get a driver? It's the little black curved piece that doesn't come out of the shuttle race when you take out the bobbin, hook, and shuttle.

How can I time my sewing machine?

Answer 1

I hope you are very mechanical-minded. Your machine is out of time, no more, no less..it happened when you broke the needle. Out of time means that the hook is not passing the needle eye at the proper time...all the cleaning in the world is not going to help...and truthfully, it also sounds as if there is not thread tension applied to the thread when the foot is down.  so here is what you do:

1) Timing!: Remove the bobbin, throat plate, and this will give you access to all the hook, etc. There may be a port on the side of the machine that is rubber, and if so, remove it. Carefully mark the distance the hook is mounted on its shaft! Now, remove the hook by either loosening the set s***w (probalby an allen s***w) and check out the hook...if it has burrs, then use fine sand paper and smooth it out.

(the hook is the thing that goes round, then backs up, then round, then backs up when the sewing machine is turning...you will see the needle come down into the bobbin area. The hook MUST almost touch the needle and grab the thread going through the needle just as the needle starts back up! You time the machine by placing the hook back on its shaft to depth so that it does NOT actually touch the needle, but at the time the needle starts back up, the tip of the hook (it is the "sharp" part of the hook) just passes the needle...that will make the machines hook catch the needle thread, the thread goes into the hook's grove, the bobbin thread gets caught in the grove and twists the threads as the machine's needle leaves the fabric. Make sure there is bobbin tension on the bobbin case, and there is tension on the needle's thread (this is put into play when you lower the feed dog/sewing foot. When the hook is operating perfectly (you do all this by turning the machine by hand!) tighten the hook's set s***w down on the shaft tightly.

2) Throat plate...It must be smooth, and if it isn't, sand it out to be smooth.

3) Upper tension" IF when you lower feed/pressure foot, there is no tension on thread and does not change tension regardless of the tension setting, you have a serious problem with the upper head of the machine. Remove or open the end of the machine where the needle is...check out to see why the thread tension is not releasing when the foot is lowered...there is some kind of obstruction OR it needs light oil...

All of this becomes very obvious when you open the machine...make sure then when you pull the bobbing thread when the bobbin is in its case, there is tension on the tread...too much bobbin tension will leave the sewing stitch with a straight line of bobbin thread on the BOTTOM of the fabric, too much upper tension will leave the needle thread a straight line on the top of the fabric with the needle thread...perfect balance of tension will make the "twist of thread" in the center of the fabric as you sew.

I hope this has been helpful. Goldwing