In the years that I have been working with Featherweights I've noticed that problems with Feathers seem to happen in clusters. I don't find a problem but what the problem does not repeat itself, repeatedly, within days. Case in point: a bobbin case not adjusting as it should. If yours seems to have but one setting; loose, it might seem like it is "time for a replacement bobbin case", Oh bother!
How you remove the thread from your bobbin case might determine how you will spend your next $75.00. If you function like I did not so long ago you probably remove your bobbin from the bobbin case to change thread by dumping the bobbin in your hand and pulling the thread out of the case from inside, just jerking on the bobbin and dragging the thread out screaming!. (I'm trying to make it sound like a rude thing, did it work?) But we are not going to do that any more, are we?
Instead let the bobbin drop gently into your cupped hand and cut the thread with your best gold plated (titanium bladed) stork scissors you keep warm in a velvet lined basket beside your Featherweight.
Now, pull the thread out of the bobbin case from the outside which is pulling the thread out from the case in the normal direction the thread would travel.
Why? The bobbin case is designed for the thread to pass through it one way. That's why there are no options as to how to install the bobbin case even though some have tried. If thread is pulled backwards through the bobbin case (as in; jerked removed from the inside) the little metal strap on the outside of the bobbin case (that is the tension spring) will "shave" the lint from the thread making its own lint if there wasn't any. This "free-at-last" lint collection builds up under the open end of the strap spring and it can have enough body (mass) to hold the spring's tip up and off of the side of the bobbin case allowing the thread to just pull through this tension device without resistance (tension). It will be held up and off by the tiniest amount and it will not be easy to see unless you really look.
Cure? Stop pulling the thread the wrong way. If you already have a zero tension case; remove the tension adjusting screw (over a towel!!!) and loosen the screw at the end of the strap about one turn to loosen the strap. Using a flat tooth-pick, inset the flat end of the tooth-pick under the strap about where the tension screw was and wipe sideways to the tip of the spring where the thread comes out. The pellet of lint that comes out will be tiny and you'll think that I am pulling your leg, but April-fools Day was yesterday and I'm over it.
Put things back together, reset the tension and enjoy. It is possible you might have to remove both screws to clean out completely from under the strap tension spring. Please work over a towel to keep from loosing one of the screws.
