My 15000 has been perking along pretty happily but I have noticed that the upper thread will jump out of the uptake lever while I am sewing ... and then, of course, it won't sew because of thread snarls. I am trying to be careful while threading; is there anything else to try? What is weird is that I will have been sewing just fine and it will do this on its own. It hasn't done this during embroidery, at least not yet. TIA for advice.

Patti, waiting for rain in Oregon

Slipping out of his easy chair, Jim says:

Start opening the door when threading to make certain that the thread is completely in the take-up lever. You'll notice that there is a little clip to keep it from coming out. If that clip is not closing completely then see your dealer about replacing or adjusting it. If you find that it still comes out with the clip operating correctly, then the thread is probably looping over the top of the lever and snapping in a second time, which will immediately pull out through the eye. A misadjusted check spring could cause that, which is also a dealer adjustment.

I had this problem in the past with a 6600 customer. In her case I fixed it by adjusting the take-up lever, but prior to doing that she had gotten a tip from one of the lists that helped. That tip was to take the thread around the left side of the lever while threading, rather than the right.

This is driving me bonkers. I wonder if anyone can advise me please. I have the 12000 and when I am embroidering, I keep getting a little "metallic" noise, just before the machine stops with the "upper thread broken" message. When this happens, there is also nesting under the hoop. The machine was serviced two months ago. I have changed the needle, cleaned the bobbin area thoroughly, re threaded and re threaded loads of times, but it's still happening. I'd hate to have to send my machine back for repair - 500 miles - especially after just having it serviced. Am I doing something really stupid or could there be a fault? I'd so welcome any ideas please, before I tear my hair out.

With a long history of being bonkers, Jim says:

My best guess, from thousands of miles away, is that there is a burr either on the bobbin case or the hook race. This type of problem manifests itself with the symptoms you've described. Remove the needle plate and bobbin case. Examine the bobbin case, especially on the bottom. It should be very smooth with no rough places. Look at the rim on the bottom for little bumps or holes. If hit by a needle it will leave these. On the bottom if you see a thin gray or white line it may indicate a burr on the hook race itself. These tend to file away at the bottom of the case, leaving a trail of fine dust. You may not notice any stitching problem except when the hoop is traveling in a certain direction, causing just the right pull to snag the thread on a burr. Use a lot of light and a magnifying glass to examine the edges of the hook race that the bobbin case sits on. If it has ever been hit by a needle there may be a small nick, which will snag thread. Once a single stitch gets caught you will quickly get a thread nest, as further stitches catch on the caught one. If you find one or more burrs they can be polished out with a suitable polishing stone, but it takes patience and the right shape and size of stone.

If you don't find anything in your inspection, try changing bobbin cases before sending it off. If that clears up the problem you can just order a new case. If you do wind up sending it off, and the problem is in the hook race, you may not get the resolution you want. Most dealers look at thread nesting and reflexively think that the needle tension is the problem. Insufficient top tension will cause loops, so it's not an unreasonable position. However if the problem is a burred hook, which is MUCH more common, they will fiddle with the tension without correcting the problem and you could wind up with two problems.

Janome's rotary hook system, with the bobbin case held by a magnet, is a marvel of engineering. It is also somewhat of an Achilles heel. Since there is a magnet at the bottom of the hook race, the part cannot be made of steel. Instead it is aluminum, which is a soft metal. One needle strike can create enough damage to cause stitching problems. In my years of servicing machines, hook damage was something I looked for in every service. Most of the time I could polish it out, but some machines would come in with a hook that looked like a cheese grater. In those cases I had to change it. Every time a needle breaks the bobbin case and hook race should be checked. Undiscovered damage will cause more breaks, due to thread catching, until the hook must be replaced.