I have a 'computerized' Kenmore machine, about 5 years old. I was told not to use metal bobbins because they would interfere with the computer. I have a lot of metal bobbin that I would like to use - and they hold more than the plastic ones that came with the machine. Does anyone out there know if the metal bobbins will harm the machine computer in any way? Thanks for your help.

There are several different size bobbins(flat metal ones with only one or two holes, metal ones with holes all around, really flat plastic ones, and plastic ones that LOOK like they are the same size as the flat metal ones, but aren't quite) and they each fit different machines.

If you try to use the wrong one your machine may not stitch nicely...will probably sew, but there will be problems like skipped stitches, rats nest on the bottom of your stitching, incorrect tension, etc. Ask me how I know!!!!

Thanks, so much for your input - I guess I better get myself to Sears and pick up some 'legal' bobbins.

Most metal bobbins will not fit Kenmore.

I was told that if I used metal bobbins in a machine made for plastic, it could ruin the bobbin assembly...

coulda fooled me. i use metal bobbins in my computerized machines without any problems.

what happens, if the bobbin not not fit properly, it will wear out the bobbin holder...thats about all.

i am quite sure it will not interfer with the 'computerized' part of the machine at all.

although i would never use one in my Janome..if it is working for you..keep using them.

also, the only machines i had that used metal bobbins were side loaders..

I wouldn't try if they are not the ones that the macnine came with less thread or not.

As one of the other ladies said may look alike but not..

Metal doesn't affect the computer. Strong magnets will. When I had my Kenmore I bought pre-wounded bobbins. They are filled better and hold much more thread. Also, if you wish to fill them yourself, you can try to use 50 or 60 wt thread. You can fit in much more thread than with 40wt.

Pretty sure the metal ones don't interfere with the computer considering my Bernina CAME with the metal ones. I think it's just important to use the correct ones on your machine as it could ruin the bobbin area if an incorrect one was used.

I second the suggestion to use a 60 wt thread for your bobbin. When I switched to Bottom Line thread for my bobbin, I was amazed at how long I could sew without needing to refill my bobbin. It just kept going, and going, and going..... :)

Thanks for the help - I really appreciate everyone's response. I am new to this site and I have already asked two questions and received a lot of help.

I wouldn't use the metal ones

I also have a Kenmore and I was told that using metal bobbins could wear out the plastic assembly faster.

I have used metal bobbins for years in my mechanical, electronic, and computerized machines (I have Kenmore, Singer, Brother, Janome, and Euro Pro) with no problem but I learned something new today!

I have machines that have front loading bobbins and top loading bobbins. I took my Kenmore Elite in today, which has a top loading bobbin, for a recheck by the technician. I noticed he changed my metal bobbin out for a plastic one while he was working on it and I asked him why.

He said the sides of the bobbin cases in top loading bobbins are made out of plastic and the metal wears the plastic down. Also, if there are any knicks in the metal, it could cause the thread to gritch so he prefers the plastic because he knows there won't be problem.

He said the bobbin cases in front loading bobbins are made completely of metal so a metal bobbin always works great and won't have a problem.

I told him I had used metal bobbins in all my machines for years with no problem and he wasn't surprised but he did point out that I would probably have to replace the top loading bobbin case in my machine because eventually it would wear out. So I'm switching to plastic for my top loading bobbins.

Oh, my machine was stitching funky. What I thought was a tension timing issue was actually a worn out presser foot. Well, it was plastic and the machine is nearly 25 years old!

Thanks for the info!
I have always just used what fit in the machine.(the metal always seem thicker than the plastic)