Oh! It didn't occur to me it might be a treadle. That would make it a 15-88. Also, put in a brand new needle when you test it. A bent needle will cause that. Good luck

Hey, John -- thanks very much. I shop CL and thrift stores, Goodwill, Value Village, etc. I sometimes wonder why more people don't value these machines but then I'm thankful they don't because that means there are more for us. There are lots of inexpensive, great machines out there but sometimes they take some digging.

The Singer is the $9.99 machine, a thrift shop buy. After getting it home, I tested it by doing some sewing (no oil, right out of the case). It stitches well and is quiet. The feed dogs feed evenly, so the material remained straight while sewing. Then I opened it up full throttle at the widest zig-zag and broke the needle. It's in great shape -- nary a ding nor scratch on it. I looked for plastic innards and couldn't find any and it's fairly hefty, although the top and nose plate are plastic as is the presser foot pressure control knob and the clutch, although the hand wheel is metal. It's made in Monza, Italy. It seems to be a good machine overall. Basic, sturdy, but lighter duty than a Kennie.

The other three were CL finds and cheap!

Also if you are breaking thread, make sure that you are using new thread. Old thread can be weak and can break quite easily. You can also do a "pull test" to see how easily it breaks and if it is weak.
I like having old wooden spools on the vintage machines for display, but don't sew with them.
~G~

I also have the Singer 237 I bought it on my honeymoon in 1969 on layaway. We lovingly call her Big Bertha. I still use her today.

That is so cool. If mine ever gives me trouble, I'll know who to ask. :) I've been doing some reading about the 237 MA and apparently it's considered a good machine. So far, so good.

I often wonder about the previous owner(s) of the machines I buy. Besides attachments, I sometimes find personal artifacts in the cases or tables and these items can be intriguing. Often the seller will indicate that the person who owned it was a mother or MIL who passed away and that they just don't need or want it. It saddens me a little and causes me to treat the machine with more respect than just a nice piece of machinery.

Thank you, Grant. I was thinking that might have been what it was.
Sharon

When I saw the NOS, I thought of "Not otherwise Specified" and not New Old Stock!! :D

Ode to Big Bertha
Your 237 won't give you any trouble, she'll do what ever you ask of her and won't skip a stitch ever. In the 45 years I've had Big Bertha I've made most of my kids clothes till they hit high school than she taught them how to sew. Big Bertha and I have made so many full size quilts I can't even remember most of them. She even helped me make a quilt we covered one of my sons up with in his coffin, I think she was crying along with me.
She has given us much more than we've given her. She was and still is so much a part of our family. I only ask they bury me with one of her needles and they give Big Bertha to another family so she can help raise them as well.

That's very sad, Sharon. I'm sorry for your loss. I hope someone else will love Big Bertha as much as you have.