Reader Questions: Eric's Knee-Operated 15-91

All photos in this entry by Eric from Ottawa

Eric from Ottawa writes,

[The 15-91 I recently acquired] looks like it's in great shape, but it doesn't run. It has a knee switch rather than a foot pedal and it looks like the motor controller has failed. 

To test it, I unscrewed the center of the flywheel so there was no load and plugged it in and got nowhere, even with the knee switch in and fully engaged.

Do you think it's worth re-wiring it to use a standard foot pedal like most of the ones I've seen?

Hi Eric, first off, a little about your machine. The chrome rim on the handwheel plus the design on the faceplate, from the little bit of it that we can see in the photo up top, indicate this machine is from the 1930s or early 1940s (assuming those parts are original). The old-school cylindrical Singerlight visible in the photo below also indicates the machine is from that era.

The “J-“ prefix on the serial number plate indicates your machine was made in Singer’s Canadian plant in Quebec.

Secondly, good on you for trying to run the motor with no load, that’s exactly the correct first step to test out a motor.

A Visual Guide to Identifying Singers from Crappy Craigslist Photos, Part 2: Narrowing Down the Model 15

In the last entry we learned to deduce if we were looking at a model 15--or something else--based on the giveaway "runway" and "ski jump" of the machine's profile.

If it is a model 15, we'll next figure out if it's a 15-91 with the potted (direct-drive) motor, a 15-90 with the side-mounted (belt-drive) motor, or an earlier model 15 that might have been treadled, hand-cranked or converted to electric.

If it's a 15-91 or 15-90, it will have minimal decals on the arm, just saying SINGER with some slight flourishes (see top photo). Earlier model 15s will have more extreme, ornate decals on the arm and pillar, like these:

Photo too small to see detail, but you can see a lot of gold on the arm, too much to be a modern 15.

Screwdrivers, Part 4: Bits That Will Fit a 15-91

If you've already got some assorted screwdriver bits that will fit parts of your Singers, and a bit-holding screwdriver handle, you don't need to purchase an entire set. You can save a couple bucks by ordering just the individual bits you need from a company like Brownells. So what I've done here is photographed the various parts of a 15-91 and labeled, below, which Brownells bit will fit it. (I figured looking at photos of the screws in question is easier than figuring out the name of the screw and checking that against a list.)

You can then order the bits you need at this link to Brownell's website. They're $2.99 a pop. Happy fixing!

How to Restore Your Stitch Length Indicator Plate

Okay folks, today I'm going to show you how to get those pretty gold numbers back onto the stitch length indicator plate, so you can actually read the darn thing. Here's your typical "attic fresh" 15-91 that's seen better days:

The stitch length indicator plate's numbers have been worn away by time, making the numbers illegible.

Now I'm gonna show you how to fix that.