The Singer 337 appears to have been manufactured in Scotland for the 1964 and 1965 model years. The writer has seen two versions of it. One, like the one reviewed here, without a needle position selector, and one with the needle position selector. He does not know if they were two different models or just ’64 model and ’65 model differences. He has also seen two color variations, light blue like this one, and light green. The both seem to have the same greenish plastic top cover.
The 337 is a basic Zig-Zag machine, with a drop in plastic bobbin. The top arm cover is plastic, the name plate is plastic, the tension dial, but not the mechanism, is plastic. Every thing else is metal. All gears are steel. The machine is technically a horizontal rotary oscillating hook type which tends to be very reliable. The lack of frills also lends itself to reliability. Since it has dual tension slots and an oscillating hook, it should only be a matter of adding a second spool pin to use twin needles with it.
There was a slightly more expensive companion model, the 338, that had interchangeable cams and thus a wider selection of stitch types. As far as the writer can determine the 337/338’s are very similar to the proceeding 327/328 which had an external motor, and the subsequent 347/348 which had a belt driven rotary hook. He was unable to find a Service Manual for the 337/338 but has one for the 347/348 and the only difference he can see is that the 337/338 has a walking bar driven oscillating hook, while the 347/348 has a cogged belt driven rotating hook, and a couple of nylon gears.
There are two main levers on the front. The vertical one controls the stitch length and forward/reverse. The stitch length can be varied from 7 per inch to 30 per inch; plus there is a setting for 6 stitches per inch basting, but it is locked and the lever can not be moved to reverse at that setting. Just below that lever is a switch for the light. And just above it is the Bobbin Winder control. The horizontal lever controls the Zig-Zag with from Zero, straight stitching, to 5, about a ¼ inch wide. On the model with the Needle Position selector that is just to the right of the Zig-Zag selector. There is, of course a knob to adjust Thread Tension. A foot controller for Motor Speed is the only other control on the machine.
It uses a standard 15×1 needle, plastic bobbins, a 15 watt bayonet light bulb, and sewing machine oil all of which were available at the local Wal-Mart. You also need a small tube of sewing machine grease for two gears in the top that the local Wal-Mart did not have.
The 337 uses Low-Shank feet like most Singer Machines, except the Slant-Needle ones, since 1851 and many other makes; so sewing feet are easy to find. Look for “Low-Shank, Featherweight, Singer, etc. The reviewed machine came only with a Zig-Zag Foot. The writer has acquired a couple more from eBay and has found no problems with them.
Bobbins are wound with the thread spool in the sewing position. The thread is run to the front clip above the Thread Tension Control, and back down to the bobbin tension button near the base of the pedestal then up to the bobbin. The bobbin winding selector is pushed to the back of the machine and hit the foot control. It only takes about a minute to fill a bobbin.
As mentioned the bobbin is a drop in one. Just open the bobbin cover by sliding it towards you and drop the bobbin into the bobbin case. Slide the thread under the tension spring and into the slot on top of the bobbin case. Then close the bobbin cover with the loose end hanging out. Hold the needle thread and cycle the machine with the hand wheel with will pull up a loop of bobbin thread. Catch that loop and pull the loose end through. Nothing fiddly about it at all.
Can not say the same about the upper threading. However every old vertical needle Singer the writer has ever used is threaded exactly the same way. From the spool to the thread guide, down around between the tension disks, lift the tension spring with the thread and loop over the hook, then run it through the hole in the lever, down to a guide on the front plate, and then one on the needle bar and through the needle eye front to back, flip it under the foot and towards the back of the machine. Done.
So, how does it sew? About like an old Singer Sewing Machine. In other words, if there are no problems with the machine, there are no problems with the sewing. If there are problems with the machine there is a lot of help out there for the asking.
The only potential problem the writer can see with the machine is that it apparently was only made for two years. That means that any parts that are unique to it may be hard to find replacements for. On the good side of that is that most of the parts are commen with other model singer sewing machines, so he has no problem recommeding the 337 to anyone looking for a basic reliable zig-zag sewing machine.
Your Comments and Corrections are always welcome.