Good for you. Yes, you will need to have a longer stitch length. Have you tried some different fabric?
It is quite possible that something is loose, bent or just needs some fresh oil. A manual can be found at
https://www.singer.com/support and specifically at
https://res.cloudinary.com/singer-se...ct/245_192.pdf
I was trying to find a 99k manual as the the Spartan is just a
spartan 99. I have one, but cannot find where I got it from. Perhaps it was on an old Yahoo Group that isn't around any more.
I have a 99-13 and just has a screw to adjust the stitch length, rather than a lever. According to the manuals that I have, it looks like the stitch length lever doesn't need oil. If you look at the bottom of the machine and move the lever you may be able to see some parts that move and even if just a little, oil all the parts that rub together along the path from the right side of the machine to the feed dogs.
As I am trying to help you figure out this machine, I thought about the pressure on the presser foot. There is a 99/99k machine manual at singer.com - specifically
https://res.cloudinary.com/singer-se...ng_Machine.pdf that describes the adjustment on page 22 of that pdf.
Hopefully, something in one of the manuals may help.
Janey - Neat people never make the exciting discoveries I do.
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