Can anyone tell me how to tune a 306K?
Awesome machine! I have done so much work with this baby, including building a mainsail (9oz Dacron) for my yacht.
But it has slipped out of time, driving through hot-knife-cut webbing.
Can you help me get this machine back on track?

What do you mean "tune"? Lubrication is usually sufficient and the manual is freely downloadable. Have you changed anything, such as the needles? I oil mine and use 206x13 needles and have no problems ever.
If you're using the right needles and it's well oiled, could a gear have slipped? Check the hook timing (I had to Google it).

Here is a lot of info - it is about a Singer 319 but everything but the keys on top apply to the 306: http://www.quiltingboard.com/picture...c-t162425.html I was learning a lot - there was a lot of help there from QB members. You may be able to find the info you need.

Thanks, friends! very useful info. I just needed to include the keyword 'hook' in the Google search. Though I've owned this machine since 1972, I've never had to learn about it, because it just goes! But suddenly, the needle is hitting something in the bobbin mechanism, so the machine cannot complete a stitch. I think something has slipped, the mechanism stops abruptly with the needle just entering the bobbin space. Will follow the advice you've offered, fingers crossed!

If I had to guess I'd say your use of a domestic machine to sew heavy canvas has caused the timing to slip.
Very easy to fix but it will probably happen again if you keep using it to sew sails together again. If you really want a domestic machine to do this, a 201 would be my choice: It will take more punishment than the 306, and they're very cheap nowadays.

If I were to guess I would say check to make sure you have the right size needle. If you have a regular needle from any where close to your house it is wrong wrong wrong. You need to order the right size.

Ive posted this before. If your brave and are willing to fuss a bit with your machine you could try this. I did it with a machine i found it works. It took me 3 hours. Lol read the comments on the video theres some helpful hints https://www.youtube.com/watch?v=fzhR...e_gdata_player

I assume you know this:

http://parts.singerco.com/IPsvcManuals/306W25.pdf

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