The Singer 401A is legendary for its durability and power. Like the old Timex, it can take a lickin' and keep on stitchin.' After all, it has steel gears, doesn't it?
Yes, the 401A is famous for it's Made in the USA steel gears, but did you know that the 401A has ONE gear that is NOT steel?
In fact, the gear in question isn't even metal.
"Say it ain't so, Joe..."
The 401A is often touted as an "all metal" or "all steel" sewing machine, but neither description is strictly accurate.
The 401A machine head is cast aluminum, which is lighter-weight than the earlier cast iron straight-stitch machines. The 401A's casting is heavier than the Featherweight 221 or 301, but it's still aluminum.
Inside the 401A, the needle bar, cam-stack, cam followers, hook, and driving gears are nearly all steel parts.
Nylon handwheel gear - Singer 401A
The exception is the large gear that sits just inside the handwheel and engages the upper machinery to the vertical motor drive shaft. This particular gear is 1/2 inch thick and made of an extremely durable plastic composite.
It may not be steel, but whatever the stuff is, it stands the test of time, because you never hear of this gear stripping, breaking, or cracking. Unlike the plastic and nylon gears that Singer used on later models, this substance just quietly does its job year after year after year.
The material in question is most likely Textolite, which consisted of woven fibers infused with bakelite. If you examine these gears closely you can see the cross-hatch of woven fibers, and the service manual for Singer 201 refers to a similar gear as a "textolite gear." Textolite was a brand-name patentend by GE in 1936 and heavily promoted through the 1950's for everything from laminate counter-tops to tile floors.
So now you know the 401A's dirty little secret. It's not "all steel" and it isn't even "all metal." But it is still unquestionably one of the finest Singer sewing machines ever built.
Happy Sewing! Barbara OldSewinGear...dedicated to helping you get the most out of your old sewing gear.
OldSewinGear is the collaborative effort of retired repairman Gary and daughter Barbara. We love old sewing gear and enjoy sharing what we've learned in our vintage sewing machine adventures. We are located in Roseburg, Oregon.