Always check manual for correct bobbin size. My singer takes a singer 15J not a 15. Size 15 is slightly smaller and will jump around in the bobbin holder. If do not have manual check on line or call local distributor or even here on the board.

Wow! I better pay attention - I didn't know I could be using the wrong bobbins in my machine. I bought a new machine and am using the same bobbins...the machines are singer and brother...I better go check it out before I ruin me new one. Thanks for this info.

You'll be able to tell the difference immediately when you get the correct size bobbin. I can get the cardboard sided pre-wounds to fit in all 4 of my machines but I have to tear the outside facing paper off for 3 of them. My machines won't even wind each other's bobbins. The spindle is a different size.

sometimes the bobbins look like they are right, but just a hair off can really change the machine proformance.

I think the crochety man should have told you what you need. Anyway, my machines won't work at all with the wrong bobbin. What machine do you have?

So true, so true, the correct bobbin is essential. Again yesterday, one of the guild members was having tension problems, wrong bobbin. Just because they all look almost the same they aren't, use what is recommened for your machine and you and your machine will be much happier.

Agree wholeheartedly! I have had experience with using the wrong bobbin and it can ruin your day!

Many machines although having different names actually use some same machine parts manufactured by the one company, this means you can use same bobbins in some cases, however I recommed always checking which bobbin is right for your particular machine first. Over the years I have owned a Singer, Liberty, Jamome, and two different Brother machines, they all used the same needles and also the Universal needles. It seems like there are no rules but there are in fact. You may not do much damage to your bobbins but you may do permanant damage to the inside of your bobbin case, if metal on metal is spinning around in there at a 100 miles an hour, if it is too tight for instance, you will wear something out pretty fast! One gets used to the way your machine sounds and sews, changing to the correct needle, often you can hear the difference! I write this for anyone new to sewing and machines etc as any info on machine maintainance is good info IMHO.

Gal

I put a colored mark on the correct bobbin size for each machine so I can get the correct bobbin in the machine. As usual each machine takes different bobbin and it it is hard to tell difference.

I have marked mine also, Hot Pink nail polish on the Brother and Blue on the Viking. And I can tell the difference in the vintage ones just by looking.