broken hand spring repair

[moptop]

I'd like to ask you all for some help in finding info on repairing a broken hand spring by replacing it with a round one make from spring wire. I know I read a post about it somewhere but I cannot find it. My buddy just bought a very ornatley engraved '51 navy and the hand spring is broken. I thought I would try to reuse the old hand and just make a new spring rather than just replacing it saving myself the trouble of having to shape and fit it to the revolver.

Thanks much!

[Nobade]

I was given an old Navy Arms '51 because of the same problem. I ended up drilling the frame to take a coil spring and plunger, like a Ruger. The grip frame holds it together and it works really slick. Or at least it would if you put the hole in the right place so it is directly behind the hand. I had a vapor lock moment and put it a little off to the side. Still works fine, but I had to make a plunger with a smaller nose to fit right. Next one will be better!

-Nobade

[RPRNY]

New hand with spring available from Dixie for about $6. Will require some slightly delicate filing to make it fit just right. Buy two in case you frack one up first time.

[Battis]

I use bobby pins. They're flat and fit perfectly in the hand slot.

[KCSO]

The problem with replacing the hand springs is crimping them in solid. You almost need a jig to do the job right. I made a crimping jig from an old iron face.

[moptop]

KCSO, Yes, I thought about that. I heard some just solder it in place but I would think that any heat applied to the spring would cause it to lose its temper and stiffness.

[Hellgate]

KCSO,
After raiding my daughter's hair pin drawer and cutting the bobby pin to the proper length, I put a couple indentations or notches in the portion that will be held by the slit in the hand where the old spring used to be. Then I stake the spring in position so it can't come out of its slot. I have at least 3 Colt re[pros with bobby pin hand springs and so far, have not had one break.

[Omnivore]

If you happen to have a woodwind instrument repair shop nearby, they'll be intimately familiar with the problem of installing a new, tiny flat springs. They do it all the time, so they'll have the tools and parts in stock. I had a Colt hand spring break, leaving the piece of the spring still crimped in the hand slot. I drilled and tapped for an 0-80 screw and used a clarinet key flat spring and screw. That was a few years ago, it only took a few minutes, and it's still working fine.

There are several ways to skin that cat. This is just another one. Musical instrument flat springs also tend to have a little "ski tip" or turned up tip at the free end, which makes them slide against the frame more easily. My Colt never felt so good before.

[Nobade]

If you happen to have a woodwind instrument repair shop nearby, they'll be intimately familiar with the problem of installing a new, tiny flat springs. They do it all the time, so they'll have the tools and parts in stock. I had a Colt hand spring break, leaving the piece of the spring still crimped in the hand slot. I drilled and tapped for an 0-80 screw and used a clarinet key flat spring and screw. That was a few years ago, it only took a few minutes, and it's still working fine.

There are several ways to skin that cat. This is just another one. Musical instrument flat springs also tend to have a little "ski tip" or turned up tip at the free end, which makes them slide against the frame more easily. My Colt never felt so good before.

Hey, that's a great idea! Thanks!

-Nobade

[fouronesix]

Musical instrument flat springs also tend to have a little "ski tip" or turned up tip at the free end, which makes them slide against the frame more easily.

Here is the often overlooked "nugget" worth studying when working on many hairpin (or flat) spring projects. Often the contact end of the spring is simply cutoff or has a sharp edge. If it doesn't have a "turn up" or "ski tip" end, it's usually a good idea to at least hone a rounded edge. Many ML locks use a captive hairpin spring for the sear. Many, if not most, have a sharp "working" edge. Function and smoothness of the operation of the sear will greatly benefit by rounding that sharp, working edge of the hairpin where it contacts the sear.

[Omnivore]

...the often overlooked "nugget" worth studying...

You'd be surprized at how often it's overlooked in the musical instrument world too, where a smooth action is considered paramount-- the Holy Grail if you will. I've seen cases where the abrupt free end of the spring had eventually dug a trench into the steel friction plate against which it operates (or the wood or the brass) causing the key to "close" by jamming the spring tip into the trench, preventing the key from actually closing all the way to seal. It felt OK to the touch, but it wasn't working at all.

I've been able to bend a "ski tip" into an existing spring using a small pair of smooth-jaw pliers, but there are two potential probelms with that. One is that depending on the temper, the steel will sometimes crack or break, and the other is that the operation effectively shortens the spring somewhat (it's no longer contacting at the tip, but somewhere behind the tip). Therefore it's often best to replace the spring with one having both the right effective length and the right shape.

The concept applies to any flat or needle spring, really-- the free end slides against something and shoudn't be digging into that surface. It became a habit to lubricate that sliding surface as a matter of routine, and to make sure there was no mechanical interference with that sliding action.

Most woodwind instrument flatsprings have a "ski tip" built into them from the factory, and they come in a wide spectrum of lengths, widths and weights.

[Omnivore]

Heh; "Spring Theory"
There's a lot to it.