We keep getting emails along the lines of “What’s wrong with my 201 that I have to have the top tension on 9 to get a reliable stitch?”, so this is an attempt to explain a bit about how this type of top tension adjuster works, and why the number you have it set on isn’t actually as important as many people believe.
As I’m sure you know, the general idea is that en route ‘twixt spool and needle, the thread passes between two discs which are held together by a spring, and they should keep it under just enough tension to produce the perfect stitch. However, on most of the older domestic Singers, there’s no scale on the tension adjuster, and that makes trying to repeat a previous tension adjustment a bit of a lottery unless you’ve had years of practice with a particular machine
Now on this and later types of Singer top tension, there is a scale, and while to most people this is a great convenience, to some it’s a source of anxiety. That’s because their machine sews best with the top tension on 9 or maybe even on 2, and they discover that everybody else seems to have theirs on 5.
So what’s all that about then? Well, in theory, if your bottom tension is correctly set, you should indeed find that more often than not, you get a perfect stitch with the top tension set at or close to 5. In practice, though, the fun starts when somebody has previously dismantled the top tension and then reassembled it without setting it up properly. In that case, it’s very easy to end up with a unit which shows 8 or 9 on the scale when the amount of tension it’s actually applying is the equivalent of 4 or 5. Confused? Don’t be. If we take the thing apart and put it back together, you’ll see how the problem arises – and how to sort it out if it has.
OK, we have here a 201K which happens to be a Mk2 but what the machine is makes no odds. All we’re interested in is the tension assembly. Seeing as how this is actually one of Elsie’s own machines, it’s hardly surprising that in normal use she usually has it set at or close to 5.
As you’ll be aware if you have one of these, you can only unscrew the (tension regulating) thumb nut so far. When you want to take it off, as we do now, you have to unscrew it as far as you can, then push the dial with the numbers on (the tension index flange) away from the nut …
If you keep it pushed in (the end of a screwdriver might help if you’re worried about your nails), you can then unscrew the thumb nut all the way, take it off …
and then remove the dial. We can now see how there’s a pin on the back of the thumb nut which engages in one of a series of holes in the front of the dial …
It’s that which is the key to setting up these tension assemblies. But just so you can see what’s what, we’ll continue stripping it as far as the discs themselves. Behind the numbered dial is a peculiar little washer thingy with a hooky bit on it …
and behind that’s the spring …
Next comes the bit with the + and – on it, which is called the tension indicator …
and that’s as far as we’re going this time.
On the face of it, reassembly is simply the reverse of that sequence, but note that
a) when you replace the spring, the first (smallest) coil of it should be below the slot in the threaded stud (like in the picture) and
b) when you replace that funny little washer thingy, the hooky bit on it goes at the top, point facing away from the machine.
Where people go wrong is when they replace the numbered dial. It’s a bit of a faff the first time you do it, but it does get easier with practice. Here’s how to do it properly, but first a word of warning. If you have a tendency to have problems with nuts and bolts and threads, have a practice session putting the thumb screw back onto the tension stud before you go any further. I doubt it’s easy to cross-thread it, but obviously take care. Once you’ve got the feel for that start putting it all back together but …
1 Check that you have the + and – marks on the indicator at the top, the spring on right way round, and the little hooky bit facing you
2 Put the numbered dial back in place so that the ’2′ is at the top, lined up with the datum mark between the + and the -
3 Push it inwards towards the machine, hold it there, and carefully thread the thumb screw back onto the stud. Screw it in until that little peg which sticks out the back of the thumb nut tries to poke into one of the holes in the numbered dial.
4 Release the pressure on the numbered dial and jiggle it about until the little peg pops into one of those holes.
5 Now turn the thumb nut/dial all the way anti-clockwise and see what number is lined up with the datum mark on the indicator. If it stops on ’0′, you’re laughing. If it doesn’t, turn it back to ’2′, press the dial in again, and turn the thumb nut so that the peg drops into a different hole in the dial. Now see if the dial stops at ’0′.
6 When it does, check to see if you actually have zero tension with the dial on 0. To do this, thread the machine as normal up to the point at which your thread’s through the take up lever, then lower your presser foot. Set the tension to ’1′, and pull on the thread which is through the take up lever. You should just be able to feel some tension, but not a lot.
7 Now set the tension back to ’0′ and pull again on the thread. There should now be no tension in the thread. If that’s the case, turn the thumb screw all the way clockwise and see what number is on the dial. It should be ’9′.
8 In the real world, it’s often a case of arriving at a compromise whereby when the tension’s backed off as far as it’ll go, the dial’s close to ’0′ and there’s no tension on the thread, and when it’s screwed in as far as it’ll go, the dial’s close to ’9′ and there’s a lot of tension.
9 Just get it as good as you can. To fine-tune it, simply push in the numbered dial and turn the thumb nut clockwise for more actual tension at that particular position of the numbered dial, and anti-clock for less.
And from all that, it follows that if your machine sews a perfect stitch with the tension set nowhere near 5, all you need do to put things back to rights is push in the numbered dial, then without moving the thumb nut, rotate the dial so that ’5′ is opposite the datum. That way you maintain the actual setting for your best stitch, but it’s now ’5′ on the dial – just like everybody else reckons theirs is!