Juki TL2010Q has started making a soft knocking sound. I've oiled, cleaned, changed the needle, and still the sound. Any ideas what I can do next?

Be sure that your needle size is not too small for the thread you are using , thicker thread, thicker needle or a top stitching needle

When you change thread, are you using the same brand of thread and thread weight? A heavier or lighter weight thread will affect the bobbin tension. Otherwise, perhaps the bobbin case is worn. Look for a replacement bobbin case.

http://www.sewvacdirect.com/juki-bobbin-case-fits-tl2000qi-tl2010q/

You are correct. There is no mention of oil in the manual. Just make sure that you thoroughly clean as instructed. You might try changing the bobbin to see if that makes a difference. The current bobbin could be bent or damaged. If the noise continues, take it for service. Something could be out of alignment.

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check that a bit of the broken needle is not interfering with the bobbin case movement
if the breakage was hard enough it may have altered the needle / hook timing which will cause a knocking sound as well

Try installing a brand new needle. Sometimes a bent or dull needle will cause lots of racket.

You should consult your owner's manual for maintenance--cleaning and oiling instructions. Most sewing machines do require oil--some more frequently than others. Most machines also need frequent oiling in the bobbin/hook area. Be sure to use only good quality sewing machine oil for your machine--NO 3-in-1, WD-40, cooking oil, or old brown stinky oil.

If it continues to make the noise, you should probably have it serviced. Since it is less than a year old, it might still be covered under warranty, so don't delay.

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At this point I would take the manual and do a proper 'take apart and clean' on it. I have had this happen as well, and most often, even tho I don't see the creator of the issue, cleaning/oiling makes it fine. And make sure you use a good sharp needle. Nothing worse to make a machine not work correctly in a bad needle. Tighten up the needle in the machine as well. There could be fuzz on the hook within the machine.

I've look for info on changing the needle & can't find any or a manual
go to the websites below & ask them about a manual or how to
change the needle
sewvacdoctor.com
a1sewingmachines.com

having the machine check is a good idea

Your machine needs a trip to a repair person-sounds like a defective or loosened part. Also, contact Juki about this problem. I've had various problems with my Juki, but never this.

Sounds like as the machine builds up friction from extended use, some vital part is lacking lubrication and is seizing up. A good service person will remove ALL of the covers and thoroughly air clean and oil every moving part. Sometimes these dry points are hard to find and patience is required.

You can get a sewing machine oiler with a long applicator and put a drop of oil on anything that moves, but over oiling can be messy.