I have a singer 457 zig zag which is not threading/ catching the bobbin??

Hi I have a singer 457 u105 zig zag from 1965 and it misses a stitch every 100 or so zig's or zags dends where you are from I can't find any instruction manual for this machine

Allan
February 2017

how treading singer 457 105 -m cause it s broke the tread many times at once

Roberto
May 2013

http://reviews.ebay.com/singer-457-sewing-machine-top-plastic-gear-replacement_w0qqugidz10000000009193782

Mike
January 2011

Ken,
I saw your response to Emma's question on http://howtomendit.com/answers.php?id=164580. I have the same machine and it appears one of the gears on the top has "crumbled" as you suggested may be an issue. How do you go about replacing this gear and timing the machine?
Please let me know. I'm sending an email as well.
Thanks,
Ali

Ali
October 2010

Ken,
I saw your response to Emma's question on http://howtomendit.com/answers.php?id=164580. I have the same machine and it appears one of the gears on the top has "crumbled" as you suggested may be an issue. How do you go about replacing this gear and timing the machine?
Please let me know. I'm sending an email as well.
Thanks,
Ali

Ali
October 2010

Hello Emma,
Your machine may need retiming but if nothing is moving under the needle plate the nylon gear may have crumbled away wich is very common on Singer machines of that age, take the top off the machine first and look at the two nylon gears in front of you just about in the middle of the machine, turn the balance wheel and see if the bottom gear moves, if that is okay take the bottom off the machine and look at the two nylon gears under the bobbin case area and see if they are both moving, if any gears are broken they can be replaced quite cheaply by yourself and the machine retimed by yourself, I can attach timing instructions if you e-mail me.
Ken

drivewithken@blueyonder.co.uk
August 2008