The second machine, the BU, was worse, and I don't mean just the wiring. I'd owned a BU once, identical to the one staring back at me on the bench, and I'd lost that machine and it haunted me. 'This time', I said to myself, 'this time your not getting away'. I was a tad possessed. Hours blew by in a blur of eating, sleeping and being bent over the BU until it sewed.
The problem is that both machines sew. They sew with zeal. The BU performs flawlessly; nearly silent and vibration free. Its loudest noise is usually the soft snap of the needle punching through fabric. So there's my incentive. Wiser and perhaps calmer, I'll take my time, share and enjoy the process, knowing full well the possible outcome. If I can get this this done, Anne might perform like the BU, and there's a real joy in that for me; one I never imagined finding. The practical skills involved are not terribly difficult, but they were new and different and they required patience and practice. Before we get to any of them, there's some dismantling to do.
There aren't many screws and bolts holding all of this together, but it's still best for me to keep everything in the order it was removed. It isn't just helpful in reassembly, but it's almost mandatory if for some reason I'm interrupted and can't get back to the work for several minutes or days.
There are two bolts holding the motor bracket to the body of the sewing machine. Once I loosened them, I moved the motor in a way to give enough slack to the belt so that it may be removed from the motor pulley. It's a good time to check that belt and order a replacement if needed (15" to 14.75" is the recommended size for the Nova).
Then I continued to remove the bracket bolts entirely and set them aside. In the case of Anne, there was an oval shaped rubber-like shield that fitted in between the bracket and the machine body. I set that next to the bolts. The only other thing keeping me from getting the motor free of the body is the cord I'm about to replace. Since this wire is junk... the 'easy' fix here was to simply snip it off using the wire cutter part of the wire strippers.
Now I can move the motor and attached bracket to an open area of the work bench. Going back to my flat head screwdrivers, I found the correct size to remove the two screws that hold the bracket to the motor. These as well had accompanying washers. Once that was done, all I have left is the motor body.
The tricky bit. There are two threaded 'caps' that hold in the springs that keep pressure on the brushes. These caps may, or may not be of a sturdy material. Sometimes they are metal, and often they are a very old plastic.
I need to use extra care asking them to move and when they do, I'll be even more cautious because of the springs underneath. I don't need the springs shooting across the room. Crawling around the work shop floor with a flashlight looking for a two inch long by quarter inch wide spring isn't a great time. I've done it, and I don't want to do it again.
That had been my own fault for twisting too hard on 60 year old plastic.
*I should note that not all sewing machine electric motors 'must' have the springs, brushes and caps removed for the case to come apart, but since I'm here... I will check the brushes, and clean as I go. If there are some improvements I can make to the operation of the motor while I'm here, I'd rather do those now.
Right now though, I'm more concerned about a safe running motor. If you'd like an example of more a precise and technical Necchi motor cleaning, McKenna Linn's webpage goes more in depth: http://www.mckennalinn.com/cleaning-a-motor.html
With the caps safely off with the springs I could continue and remove the screws that hold the two halves of the motor together. These need another flat head screwdriver. They are quite long. Removing them allow me to separate the case and to move one half of the case with the motor armature off to the side.
Since motors are different, I've learned to look for and make sure that the washer, or washers on the armature are still on the post and in the order they were when I pulled the halves apart. This means I must check the other half to see if any errant washers that remained behind. It's this 'other' half that I'll need to manipulate to get to the wire ends and I'd rather not be surprised by washers rolling across the work bench.
To the left is the section that will need the new wires. The problem now is getting the body shell of the motor to gently slide away from the motor windings. If this motor were like most electrical motors it would slide right off, but it's not. Maybe someday I'll find the Necchi motor that will slide apart without any further hindrance, but that day hasn't arrived yet.
The Nova motor cover on the left half would not move. It would wiggle the tiniest bit, but it wouldn't slide. It's behavior was exactly like the cover for the BU, and that experience suggested the problem. What I still don't know, is exactly how best to address this issue.
The Name Plate hangup.
The name plate is the piece of metal that wraps around the outside of the case and seemingly does nothing at all except identify the motor and it's specifications. It has absolutely nothing to do with the inner workings. The motor would work just as well without it. It's trim. Not needed. Erroneous, and it's stopping progress. There are two soft metal pins (?) or perhaps headless screws (?) that attach the name plate to the metal motor body. The issue is that the pins are too long. The end of the pins have dug into the coil grooves and that's where they want to stay. They effectively lock everything right there. The cover will not move.
With the right magnifying glass, and some unknown-to-me miniature tool I suppose I might be able to turn the rounded top of these pins in a manner that might loosen them. I haven't found that tool yet. My solution - and I'm hoping someone has a better one - was to very gently pry under the metal plate around both of the little pin heads until they began to become loose. It's a slow process. Eventually I worked the plate loose and then one of the little soft metal pins fell out... which allowed just enough clearance to slide the cover away from the coil. Now, finally, I can carefully partially remove the inner assembly from the outer shell. Wiring inside the motor restricts movement here. I'll need 'just enough' space to carefully pull out the bad cut wire leads.
There are four strands of wire in this end of the motor. They are all old.
Two
of the wires are the motor leads needed to be replaced, and the other two
run from the winding to the brushes housing. These last two are secured
by screws inside and I suppose I could remove their connection and pull
the motor further apart. The thing is, I don't need to. If the
insulation on those leads looks okay (and it does) and it isn't cracking
as I ask it to move, then why mess with it? If I were to pull those
leads, I'd probably try to mark one of them and its housing with a dab
of whiteout so that I knew which lead went to which housing. The thing
is, I have enough room now (just barely) to do what I need to do.
This last picture is for my reference. I need it to remind myself that when the armature goes back into this side of the motor, nothing can be in its way. The washer on the post on the other half will make contact with the round plate shown above at the bottom of the case. The armature spins when it runs, so nothing can ever touch it, or even threaten to touch it. If a wire leaned against it, eventually the spinning motor could wear off the insulation and shorten everything out. Whatever wiring I add or replace must be safely tucked out of the way and they will probably need a little more room than the original.
How long?
I need to decide now how long to make the new leads.
I've seen other Necchi machines wired to the old Bakelite three post Singer junctions, it's easy enough to do and the parts are still somewhat readily available. I could wire it just as it was, and mount the 'Mercury' junction box in the underside of the cabinet, or I could replace it all with something more modern.
In the end, what I chose to make the leads a few inches longer than they were. When a machine has no where else to go but inside a portable case, the motor and light wires need to be long enough to reach past the deck and into the side compartment to the plug. They also need to have enough slack if you tilt the machine up from its base.
If I wire the machine for cabinet use, the leads will need to reach the junction box inside the cabinet, and they will need enough slack for when the machine is tilted all the way up on its hinge pins, and all the way down. The wires may have to be tucked along the cabinet interior to keep the slack from getting in the way of the machine's travel.
After making some measurements in the cabinet, I've decide on about two foot of wire, and I'm going to reuse the original plug with it's screw mounts so that if I decide in the future to use a different junction box, I shouldn't have to shorten the wires.
Sure is a lot to think about... but with this decision out of the way I can go back to the actual re-wiring.
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