Removing Hook On 206 Rb5, Thread Fraying

[Sovran81]

Recently the top thread started fraying on my 206. It is more prevalent with thicker threads. I normally use 138 or 207 up top and 138 in the bobbin. I have tried thinner threads and the fray was reduced but still there. I have switched needles and needle sizes. The knots are forming in the center of the material so my tensions are ok. I have checked clearances and timing using the supplied impossible to read manual. All seems to be spot on. When slow hand turning the machine, as the thread slips around the bobbin the thread and machine gets very tight then eases as the thread slips all the way around. When hand wheeled quickly or run the tightness isnt there but then the thread frays. Scouring of the forum leads me to think the hook has a rough spot even though the machine has less than 50 hrs on it. The manual is useless for hook removal. There is some kind of shield that covers the main body of the hook. (It kinda looks like a hook in reverse.) Any tips out there for hook removal so I can buff the hook. I have only had 1 issue where a bunch of thread got wrapped up around the bobbin case and I had to cut it out. Now I cant sew because the frayed thread looks horrible. anything else i might check that could cause this?

[Cobra Steve]

Hello, I would leave the hook in the machine and use some fine emery paper to sand any burrs that you might find on the outer edges of the hook. This normally works.

[Sovran81]

Been out of town and just getting back. I take it the outer edges is where burrs normally form, I assume from needle contact? When rolling over slow it seems to be stretching the thread around the bobbin case. It is when it is stretched tight I think the damage to thread is done, but I cant be sure because that shield I spoke of is covering the thread when it gets tight. It gets tight just as the thread is trying to slip over the bobbin.

[CowboyBob]

I would try what Steve said first,then check your needlebar thread guide can get a groove in it & cut the thread & also check the feed dog hole the needle goes through for needle marks that might also need to be sanded or replaced.Also do you have a frsh ar least #22 needle in it?

[Sovran81]

I will give Steve's suggestion a try and also inspect the areas you suggest Bob. Would 800 grit be fine enough or should I get some 1200? I have tried 2 needles each, sizes 22,23,24.

[Dewey]

Recently the top thread started fraying on my 206. It is more prevalent with thicker threads. I normally use 138 or 207 up top and 138 in the bobbin. I have tried thinner threads and the fray was reduced but still there. I have switched needles and needle sizes. The knots are forming in the center of the material so my tensions are ok. I have checked clearances and timing using the supplied impossible to read manual. All seems to be spot on. When slow hand turning the machine, as the thread slips around the bobbin the thread and machine gets very tight then eases as the thread slips all the way around. When hand wheeled quickly or run the tightness isnt there but then the thread frays. Scouring of the forum leads me to think the hook has a rough spot even though the machine has less than 50 hrs on it. The manual is useless for hook removal. There is some kind of shield that covers the main body of the hook. (It kinda looks like a hook in reverse.) Any tips out there for hook removal so I can buff the hook. I have only had 1 issue where a bunch of thread got wrapped up around the bobbin case and I had to cut it out. Now I cant sew because the frayed thread looks horrible. anything else i might check that could cause this?

Sewing machines are very complicated instruments but easy to understand if one studies them. Besides all the obvious things to look for consider this please: On rotary hook machines there is a needle guard which prevents the needle from ever contacting the hook point. This needle guard is made from a malleable metal and is easily bent by the person setting up the machine. When setting up a machine, it's for a range of needle sizes and if you exceed that range it needs to be set up again to accommodate the change. Hook assemblies can be adjusted to the left or right. Starting with a NEW needle, the hook assembly is tapped into place until it just misses contacting the new needle then secured there. Re-time the machine and adjust the needle guard carefully in such a way to prevent needle/hook contact.

Or you can do what I normally do which is to keep crocus cloth in my tool box and shine the burr off that pesky hook. Does nothing for the long term problem but keeps you working making stuff today. I frequently remove the hook and use a high speed fabric polishing wheel with tripoli compound to polish the hooks I work on. Hope this helped.