Fixing up New Home 551

Janome’s New Home 551 is one of those machines that you think you can easily do without, only to discover that nope, you can’t. Which is why, having sold my previous one because it was “surplus to requirements”, I had to chase for a replacement because it left a gaping hole in those requirements…

This is a Japanese-made machine by Janome from 1970s, I think, and oozing quality. It’s a heavy machine weighing 15kg and having a cast iron body, although it does use plastic gears to drive fancy stitches, but at least it is not in the main mechanism. It does zig-zag, back-and-forth “stretch” stitch and 14 patterns which combine with stretch stitch and added zig-zag to actually produce 56 patterns all together. I’ve done a stitch overview separately.

I think I may have figured out how to tell quickly which New Home machines were made by Janome Japan and which by Janome Taiwan: it’s in the colour of the logo. Japanese machines have a green square and Taiwanese ones a blue one. There’s usually also a label with model number which states where the machine was made.

However, the text is rather misleading. “As designed and specified by New Home USA”? Hardly! New Home USA didn’t design any of these machines, they are all designed by Janome based on Singer 15 architecture… Janome bought the New Home company and their designs in 1950s after which New Home USA seized to exist. New Home did have their own designs, just not these.

Replacing the balance wheel

I bought this second machine in untested condition from a house clearance sale, and it got damaged in the post – the balance wheel got broken.

Upon inspection I discovered it was made of porcelain!

I had another balance wheel in my box, so I figured it would be an easy fix – not so. The internal diameter was the same, as both machines were once based on a Singer 15 design, but the depth of the balance wheel and its profile where all wrong and didn’t fit in the existing space. If the balance wheel is not deep enough, the end nut doesn’t hold it in place and you get no rotation of the shaft; if it is too deep, you can’t even fit the end nut. It’s got to be just right, or nearly so. And it’s got to have the right profile so as to engage the bobbin winder and to fit in the cavity in the body of the machine.

A balance wheel from another New Home 551 would have been ideal, but none were available. I found something that looked like it might fit: a wheel from Jones 942 made by Brother – another Japanese machine stemming from the Singer 15 design.

The profile was right but unfortunately the depth was a little too shallow – the nut didn’t grip. I solved it by adding the second clutch ring on top of the first. I also had to replace the stop screw in the end nut by a longer one that would catch both rings.

Now we have power! 😃

The pattern selector

This is a nifty contraption which moves the finger up and down the cam stack. At the same time it also moves the indicator along a line of patterns to show you what’s currently selected.

The pattern selector is normally locked – don’t force it! To unlock it, set the zig-zag width knob to OFF.

On OFF, the pattern selector knob on top of the machine should turn very easily. If it doesn’t, if it’s stiff or if the indicator is not moving, it needs attention.

Pop off the top lid and pull off the cover of the stitch selection knob.

The small gear shown with a red arrow is the one that actually moves the finger up and down the cam stack. It meshes with the pattern selection knob. The screw shown with a yellow arrow keeps this knob in place and also presses down on a plate with notches that provide a tactile feedback for when you’ve moved to the next cam in the stack. Remove this screw and pop off the knob. It has another small gear on the bottom.

This small gear on the underside of the knob meshes with the zig-zag edge of the pattern indicator strip which moves along a scale with pattern pictures on the front of the machine. Undo the two screws marked with green arrows. They hold down a plastic strip over the stitch indicator “saw”, this strip has a groove and the “saw” has a raised edge. The raised edge is meant to ride in the groove when you turn the selector knob.

But in my machine the indicator was not moving. 😕 First it was very stiff and then it stopped altogether, so when I looked to see what the problem was, I found that the “saw” strip had slipped out of position so that the teeth of the strip were no longer meshing with the gear on the underside of the selection knob. The knob was still working and changing patterns but you could no longer tell which pattern was currently selected. 😒

I fiddled with it for a couple of hours – couldn’t see anything wrong with any of the bits and couldn’t figure out why it wasn’t working. The solution was so simple, it’s painful: dirt and thickened oil between the “saw” strip and the plastic holder strip. All I had to do was clean it up! 😤 The “saw” strip is meant to move very lightly between the metal base and the plastic cover, and that thick goo was giving enough resistance to push the raised edge of the strip out of the groove in the plastic cover which displaced the strip away from the gear on the underside of the pattern selection knob.

Putting everything back together I had to synchronise the position of the finger against the cam stack with the correct pattern being pointed at by the indicator. It is easiest to synchronise with the first pattern (number 1) because it’s the bottom cam on the stack.

• Remove the selector knob and turn the gear with red arrow until the finger comes all the way down. You can see the finger if you turn the zig-zag width knob to AUTO. Don’t forget to turn it back to OFF!
• If the finger does not move easily, you have a different problem. Solve that first, then return here.
• Now fit the pattern indicator such that it points at pattern 1 and tighten the two screws with green arrows. The screw holes in the plastic holder are oblong to allow for fine adjustments later. You need to tighten the screws fully though, or the “saw” strip might slip while you’re fitting the knob.
• Put the pattern selector knob on and make sure that it meshes both with the finger moving gear with the red arrow and the “saw” strip on the bottom. The knob should move both things when you turn it.
• Put the round notched plate on the pattern selection knob with one of the notches over the metal pip on the knob. Tighten the screw with the yellow arrow.
• Check that everything works on all patterns – go through the entire range a few times to make sure it doesn’t stick anywhere.
• Pop the knob cover on and the top lid on the machine. Done! 😃

Adjusting needle position

This machine does not have free needle positioning, so it sews straight stitch with the needle left. And because this is a side-facing vertical hook, the whole hook assembly moves left and right with zig-zag, so the relative position of the needle and the hook is always the same for every stitch in every pattern – see this post on zig-zag hooks.

On my machine the needle always hits the hook!!! 😖 So the needle is too far right with respect to the hook. By about half a millimetre.

This is the view of the zig-zag mechanism under the top lid. You can get to all three screws by setting the stitch pattern to 1 and varying zig-zag width.

The screw with the red arrow holds the lateral synchronisation of the needle with the hook. If you undo it, you will eventually be able to break the synchronisation – and to reset it. I have also undone the screws marked with blue arrows in order to get some movement into the mechanism, but I think you don’t need them.

The red arrow screw does not change the hook timing! When the screw is undone, the hook does not move left and right for zig-zag, so it allows you to set a distance between the needle and the hook and hold it for all patterns.

It is also possible to achieve the same thing by adjusting the hook depth as described in this post. It is not necessary to do both! 😉

It’s all zig-zag!

I’ve been messing about under the top lid undoing all sorts of screws that I shouldn’t have, and as a result I lost straight stitch. 😥

When I change the zig-zag width from small to large, everything works fine, but when I go back to narrow zig-zag or straight stitch, nothing happens. What have I done? 😫

In this machine reduction of zig-zag width is done with a spring, and I obviously unwound it. 😟

The red arrow marks the spring and the blue one marks the holding screw that I should have left well alone! The principle of winding the spring is obvious: turn the slotted pin clockwise to wind the spring, then tighten the holding screw to fix. The implementation however is rather challenging because you cannot let go of the spring winding pin and have to tighten the holding screw without letting the spring unwind again. If you think this is easy, try it! Or better don’t.

But eventually it was done. 🙂

I also found that the zig-zag “elbow” screw shown in the previous photo with the right blue arrow, should not be made too tight. This makes the zig-zag elbow too stiff to control with the spring, at least as far as I could wind it.

Everything working now! 😁