Leon explained a bit about the hand crank movement. If you look at the direction that the hand wheel is actually moving it is going the opposite direction from the direction you are hand cranking.
As bkay said the longer one is the regular/standard presser foot used for most sewing. The other one is what is called a quilting foot. I was kind of surprised to see neither of the manuals I gave previously did not have that foot illustrated. I've looked through so many manuals and that was a basic foot for most machines during that time. I found another couple of manuals that show that foot. One is
http://andrewcaddle.com/wordpress/wp...ttachments.pdf I don't know if that set of attachments would have been available from the Kilbowie plant. The other is a manual that is available from the Smithsonian Institute for a 15 model machine that is dated 1945, but sure looks a lot like your machine. It is scanned as a picture per page. The index starts at
https://www.sil.si.edu/DigitalCollec...2664/index.htm You can click on a thumbnail and it will open that full size image. There are arrows at the top that you can navigate to the next or previous image. The quilting foot is shown on page
https://www.sil.si.edu/DigitalCollec...es/image23.htm The threading diagram can be found at
https://www.sil.si.edu/DigitalCollec...ges/image7.htm It is a lot better than the other ones that I gave earlier.
When you asked
Although the machine has no problem with thick fabric, In its current state, it is difficult to change from 1 to 2 layers.
are you asking about sewing two layers together for a seam and then crossing another seam so that there are multiple layers to cross over? If that is the case there are a couple of videos for more modern presser feet that explains the problem and some solutions. One is
https://www.youtube.com/watch?v=U91iJMKJ23g and the other is
https://www.youtube.com/watch?v=7UVoCX1oWwc If you are asking about practice stitching on layer of fabric and then trying to stitch a seam or just layering two fabrics together to practice, then it is possible that the pressure bar needs to be adjusted.
Janey - Neat people never make the exciting discoveries I do.
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