Fixin' the Mysterious & Puzzling 2101A's Ratchet
Mehanism
Addendum - Replacing that Broken Phosphor Bronze Spring Assembly
Return to georgesbasement
Return to Fixin'
the 2101A
This is newly posted without
actually having made one.
I promise to add pictures when I've
done the task myself.
Fortunately, none of my 2100's and
2101A's have suffered this fate to date.
Randy Moore found that one of his phosphor bronze springs had lost an arm. Rather than patch the remainder of the assembly and in the process lose some information as to how it goes together, I suggested making a replacement and using the broken one as a model.
Here's what I wrote (edited for clarity). Read the whole description before starting the job:
Probably it would be easier in the long run to make a new spring assembly. I doubt that it will make much difference if you use spring steel instead of phosphor bronze, but it may be very important that the two ends be the same stiffness. That is why I would recommend against patching the existing one. Save it as a model. Try the hardware store first and see if they have some spring steel slightly thinner than, but the same stiffness as, the phosphor bronze one. Or tear some precious toy out of yer kid's outstretched arms, I don't care. All kidding aside, old toys aren't such a bad source for such springs, 'cuz the steel of which they're made is cheep anyway. Strapping is too thick & stiff, though.
You can shape the spring steel with a file, as it's not all that hard. You might even manage to drill the central hole. Use a recently sharpened drill bit, run the drill press (or your hand drill) very slow with lots of pressure, and put another piece of softer steel behind the spring stock so the back side of the hole will be relatively clean. Clamping the spring stock will be a challenge, fer sher.
If you make the hole with a punch, be sure to back the spring stock up with a thick hunk of softer steel that has a clearance hole for the punch, so the punched hole will have clean edges and the spring won't end up dished. And be sure you line up the punch with that hole, 'cuz you don't want to miss. That's why I say to use a piece of soft steel for the die. I've actually done this, and it works fine. You don't even have to hit the punch very hard.
Once the hole's in the spring, then shape the spring stock to
match the remaining half of the broken one. When the two leaves each
fit the ratchet pawls when laid flat inside their slots, then rivet the
spring onto a new pin which you can make from a nail. It is very important
that the pawls slide freely on each end of this spring, because it is altogether
too easy to crush the spring by applying excessive force on the plunger/selector
when the brace is in use. I suspect that these springs got broken when
a frustrated user bashed the plunger against the side of his workbench
...
You can use your drill press or hand drill as a lathe and file the shoulder
on the end of the nail as well as filing the straight portion of the nail
to match the pin on the broken spring assembly. I doubt that the
fit has to be real close - just don't leave it tight in the hole, or you
may never get it out ... Once shaped, use a small ball pein hammer to mushroom
the end
of the pin to hold inside the beveled side of the hole in the spring
(that's the side from which the drill entered).
If the shaping of the nail is troublesome, make a fence to fit over the part of the nail that you don't want to file. The fence can simply be a strip of wood with a hole in it the size of the nail - file the bigger part first to match the fat end of the broken spring's pin, and then slide the nail farther inside the drill chuck to file the part that fits the hole you drilled in the spring. This means that you must be sure when you start that the initial drill bit is safely smaller than the pin of the broken spring assembly.