MDF45

Success with 23s and #138, some eBay Beka 23s, not sure how old, one box of 100 says Belgium the other 100 from W.Germany, should be set for life. Ha!

I was having same problem with 206RB where the bobbin thread wouldn’t pull up no matter how tight the top tension. I was using a 22 needle with 138 bonded nylon. The problem was solved with a 24 needle. I was able to turn the top tension way back down and had an even stitch. I’m planning to try some 23s and hopefully settle on them for 138 thread.