With those last 2 pictures, I'll withdraw my condemnation of it and replace it with envy. I really didn't want to see a new sewing machine collector get burned by a repro crank.

Did you get a manual? There are 3 manuals at https://ismacs.net/singer_sewing_mac...e-manuals.html but 2 of them have different stitch length regulators. Yours is like the one in the 99-13. There are oiling instructions in the manual. Basically oil where metal moves against metal.

You want to clean the machine head with sewing machine oil as other products are likely to ruin the decals. Only use sewing machine oil, not 3-in-1 or WD-40. Also some good resources/videos can be found at https://www.quiltingboard.com/vintag...v-t167789.html

Have fun.

Thank you so much for all the helpful links 🙏

I have placed an order for sewing machine oil along with some other supplies and will be trying it out this week.

I've cleaned and oiled it and tried it out, and seems to be working well to my untrained eye. I spent some time reading the manual, fiddling with the tension on the bobbin case and the thread tension plates and the stitches look OK to me. There's quite a few people selling the tables with the pedal near me, which I'm curious about because I'm a beginner and would like to free my right hand. This one wouldn't be able to fit into one of those would it? Since it's a 3/4 size.

I'm perfectly fine learning to deal with the hand crank though :)

There were cabinets made for the 3/4 sized machines, but few and far between. Another alternative would get a motor with the bracket and a motor cord block with a foot controller. However, more than likely the cover would not fit over the motor. Even if it does, one would need to protect the bed of the machine from the foot controller as they well scratch the bed as that is the only place it will fit.

That's interesting, thanks. Not really interested in a motor so I'll be trying my best with the hand crank.

Just one more thing, my stitches at the moment look like this. They look a little wobbly (they are set pretty close together in this case too) but is there something wrong with them, do you think I need to make adjustments to the tension?
https://cloud.tevildo.top/s/f2MWTJHw69WEAX5/preview

My 99K. I didn't know the cabinets were rare. This one was donated to me.

The wavy stitch is caused by the thread size not matching the needle size. If you look at where the stitch interlocks, what we call "the bald head", those points do line up.

Thread, needle, and needle point, ​​​​should match the weight of the fabric being sewn. For instance, mending cotton denim, a size 16 needle, which has a larger eye, and accepts a heavier (thicker) thread, universal tip. Stretch denim, a size 14 ballpoint needle. Sewing a quilt of cotton? A size 11 or 12 needle, sharp tip. Constructing a tailored dress shirt? Perhaps a size 10, topstitched with a size 8, and a fine thread.I

Needles become full with use. Change out every 6-8 hours of sewing. Oiling you machine should be done every 8 hours of sewing, too. Did you find the oil ports on the hand crank?

Thank you so much for explaining it to me. I'm glad it's not something wrong with the machine. I will have to go out to get more varieties of thread, this is the only one I had around to test with.

Yes I found the oil ports in the hand crank thanks to the helpful videos at How to Clean Up and use a vintage sewing machine - videos by Muv and Fav - Quiltingboard Forums

Sorry, I was without internet and couldn't reply. A couple of links that may explain it -- https://web.archive.org/web/20110818...-about-it.aspx
https://www.quiltingboard.com/vintag...d-t255547.html
There is a more technical thread on another board entitled "My 201k is sewing like a zig zag machine!" but you have to join the forum it is on to see the pictures.