OK, first, the instructions did warn that the tender thread would be a problem (my words). I found that less then slick thread, and/or tender thread would indeed break. Normally it would break at the hooks. I found that the hooks had rough edges on them. It appears as if it is from the paint. I took my rotary tool (aka Dremel) and used the fine tapered stone to work the edges. I then used a tapered ceramic polishing stone followed up with the polishing felt tip and red rouge. It did a good job and unless you have a heavy hand it works as well as advertised in every way. It is apparent that only a few are rough, but, if yours is, and you have the tools, and are careful, the above method will work for you. For very fine or tender thread I still advise you use one of your old favorites from before.
