I have had a few enquiries about re-timing or removing the hook on the 320. After the removal of the throatplate, the instructions would be the same for a Singer 306 and 319 and probably a 206, although I've never re-timed mine. This method can be followed to re-time the machines to take standard needles instead of their special size, just use a needle of the size you wish when actually timing the hook.
Just to refresh your memory, the Singer 320 is the green free-arm with a wooden flatbed.
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| Singer 320 from front |
Before you commence this operation ensure that no cams are engaged (all the 'keys' on top are lying down), that the width is set to zero and needle position is in the centre of the throatplate. If you don't, the timing will be off when you come to stitch zig-zag with it and you run the risk of hitting your hook, which is bad for both hook and needle.
Firstly you will have this:
Remove the bobbin case, foot and needle before going in further. Keep the needle handy because you will need it again to re-time the machine. Now remove the throatplate. For those of you not familiar with this, take a narrow flat-head screwdriver and slide it into the depression on the LHS of the free arm, between the body and the throatplate of the machine. Gently twist the screwdriver and the throatplate will pop off. See image below if my instructions are bad!
Now you will have something that looks like this:
Next remove the feed dogs by unscrewing the screws circled in red in the image above.
For the next step use a fine point black marker to put marks on the machine as indicated by the arrows above. Make sure that the needle is at a point you will remember, ie. at the top or bottom of its cycle, when you do the markings on the hook assembly. These markings will give you a vague idea of how to fit things back together. Even though we are altering the timing and thus the marks on the assembly will not line up when we've finished, it gives an idea of approximately where the hook should be.
If you do not intend on removing the hook assembly and just wish to re-time the machine, skip the marking and just loosen the two grub screws holding the hook assembly on the shaft.
Once you have marked the machine, completely remove the screw holding the crooked piece of metal on and remove that piece too. Now loosen the grub screws holding the hook assembly on enough that you can slide the whole assembly off in your hand. You will need to wiggle it gently to ease it off.
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| The arrow in the image points to the hook. |
You can now clean out the assembly and dismantle it further using the screws and metal clips on the side. When it comes to re-assembly, place the hook assembly back on the shaft, ensuring needle is in the appropriate position for the marks and replace the crooked piece of metal, aligning it with your marks and screw it into place. We can now re-time the machine.
For those of you who just want to re-time their machine, join us again here. Now put a needle in your machine. If you want to re-time your machine to take a standard needle, put a standard needle in your machine, flat to back. Gently rotate the machine until the needle is in its lowest position and just starting to ascend. Now hold the needle still and rotate the hook assembly by hand until the hook is tip is just near the edge of the needle and about 1/2 way across it. The arrows in the images below point to the hook and the eye of the needle.
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| A bit too far away, the hook is not passing near enough to the eye of the needle |
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| The hook is passing close to the needle and closer to the eye. |
You do not necessarily push the hook assembly onto the shaft as far as it will go, you can pull it out slightly so that it is closer to the needle. However, make it too close and the slightest deflection caused by sewing will cause the needle to scrape the hook.
Once you have the hook positioned to your liking, tighten the grub screws tightly. You should be able to reach one with the hook in that position, tighten it hard and then very gently rotate the machine until you can reach the other and tighten that hard too. Once you have tightened the screws, carefully rotate the machine ensuring that the needle is not hitting or being deflected by any part of the hook assembly. Now set the machine to the widest zig-zag and do the same, ensuring there is adequate clearance at all times between the hook and the needle of the machine. And that's it! Screw the feed dogs back on and carefully press the throatplate back into position. Sew a test swatch and check that the machine is picking up properly on all needle widths and you're done.
Don't worry if you stuff up your first attempts, whilst it's irritating to have to pull the thing apart and start again, once it's timed properly it will be a joy to sew on.
