Vywr
Member
I was disassembling/restoring an old Yankee No 33H push screwdriver, and I ended up breaking the chuck. I was able to remove it from the shaft itself (it was just a press fit), but I couldn't get the collar itself apart. I thought it must also be press fit (I didn't see any other way it would go together), but it wasn't that simple and I broke it.
Anyway, I still wanted to see how it worked and was assembled, so I took the rotary tool out and cut it open:
Honestly, I'm left with more questions. The central piece seems to be a solid chunk of metal, so I'm not sure how they got the springs, washers, and outer sleeve into the grooves.
There's also another small hole on the other end (toward the handle), which I'm not sure of the purpose of. Maybe I lost a part without realizing it?
I couldn't find much info, let alone pictures (aside from a patent for a similar design), about how the chuck on these screwdrivers is put together, so hopefully my error can help someone else in the same situation.
If anyone has a damaged Yankee screwdriver to serve as a donor replacement please let me know! I'd rather not gut a working one.
(I'm aware they're not hard to find on the used market, but this was my grand- or great-grandfather's so I'd like to get it back to working condition if possible.)
I'm also considering drilling out one end of a modern 1/4 bit extension adapter and press fitting it onto the shaft, but I don't have a lathe and a correctly sized drill bit might be hard to find.
PS: The images have alt-text where I attempt to explain the parts and how the chuck seems to work.
Anyway, I still wanted to see how it worked and was assembled, so I took the rotary tool out and cut it open:
Honestly, I'm left with more questions. The central piece seems to be a solid chunk of metal, so I'm not sure how they got the springs, washers, and outer sleeve into the grooves.
There's also another small hole on the other end (toward the handle), which I'm not sure of the purpose of. Maybe I lost a part without realizing it?
I couldn't find much info, let alone pictures (aside from a patent for a similar design), about how the chuck on these screwdrivers is put together, so hopefully my error can help someone else in the same situation.
If anyone has a damaged Yankee screwdriver to serve as a donor replacement please let me know! I'd rather not gut a working one.
(I'm aware they're not hard to find on the used market, but this was my grand- or great-grandfather's so I'd like to get it back to working condition if possible.)
I'm also considering drilling out one end of a modern 1/4 bit extension adapter and press fitting it onto the shaft, but I don't have a lathe and a correctly sized drill bit might be hard to find.
PS: The images have alt-text where I attempt to explain the parts and how the chuck seems to work.
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