Sunday, December 1, 2019

Deep Knee Bends

I'm having knee problems; No, not my knees but knee controls. Bernina Record 730's can come with a knee lever as speed control and although I have one of these machines I cannot find a lever for it. Two have sold while I was searching so I'm not sure what I'm doing wrong in my search that I cannot find and purchase before it is gone but I'll keep trying. It's the all metal folding kind, not the one with a plastic handle (the connections are different):
Bernina Record knee power control (not presser foot lifter)
While I continue to search for this elusive knee bar control, I picked up a Singer 99 in a bentwood case that also used a knee bar for speed control. The wiring looked unsafe so before I could even test it out I needed to fix that wiring. It was a model that used these very old plugs but you can take them apart and add new wires:
Plugs that need new wire
Screw for tightening down the new wire (red circle)
Even the funky plug connection was different than most so I added new wire and a new wire and plug to the outlet. It ran but things just didn't look right. Come to find out, the knee lever pulls on an internal lever to activate:
Control box and how it should look inside
How mine looked: see lever out of the slot
and it wasn't in the slot but next to it. Wait a minute, the whole thing isn't screwed down. When I removed enough of the mechanism I found three screws floating around in the bottom so it must have been tinkered with and not returned to its original state. I got it all screwed down, every lever in position, and it worked. Well, there was power to the motor but the sewing machine needed oil and cleaning to rectify the sticking points. As I worked with it all of a sudden it just didn't work. Dead. No power. Since my husband had been sitting at the table at the time, we discussed all of the possible problems and why it suddenly stopped getting power. Out came the multimeter, going over all of the steps we took before this happened, but he kept saying "It's gotta be the box" meaning the metal box where the controller was housed.

Now I took everything apart, again. and when I pulled up the controller there was only one wire connected. It needs two. Upon closer inspection I could see where the wire had finally snapped off. No wonder! With very careful work I could pull through enough wire to give it a new connection, making sure there was no wire touching the metal box. Warning! Warning! Warning! I am not an electrician and only do what I know is sound, having either my husband check my work or I consult with a son-in-law who is an electrician. Do not take chances with electricity!
This one looks pretty nasty inside but both leads are connected
Once I got things back in good shape, it finally ran but needed that cleaning and oiling, all easy in comparison to replacing so much of the electrical system. But there's another part of this tale: I sold the same model to Jordan and the knee lever was not in the right position. I was sure I had worked on it and there was no repositioning of the knee lever. But maybe the lever in the control box wasn't inside the slot to put it in the correct position. Here's the steps to correcting this problem (lever positioning, not electrical connections):
How it looked before with lever outside of the correct slot (green circle)
Remove screw (purple circle) to either lift lever off or up
Move lever (red circle) into place and tighten everything back up
As you take it apart it might fall into too many pieces so take a good look at it before you start to see how it all fits back together. You only need to check the wiring and to make sure the lever is in the correct position.

Icy weather out now so we are hunkered down and sewing. What's up now? An embroidery machine! That's next up so stay tuned.

2 comments:

BarbaraShowell said...

I’m glad you write this blog. Always something interesting going on. I confess though, this time I’m commenting to see if a comment will post as I’m having a great deal of trouble posting on blogger blogs!

Karen said...

Here's the problem with comments: as bloggers, if we leave comment posting open we get bogus comments to promote others websites and products. If we leave comments on moderation you do not get to see your comment until it gets noticed and approved. Not much of a win-win but I keep a close watch on comments. I have to. I always like yours, Barbara!