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Sean Hughto
07-10-2013, 2:47 PM
George,

I was hoping as metal worker, you might be able to tell me or send me to the right resource to figure it out: I have a little antique cupboard latch that moves a small bar in and out on what I'll loosely call a "spring." The spring is really just a bit of wire wound to a circle with the ends extending as straight levers that fit into parts of the latch assmble so as to move the bar and the button as required. The orignal - after a 100 years or so of use I'm guessing - sort of frayed - corroded and snapped at its main action point on the circle. I need to make a replacement, but I don't know 1. what sort of wire to use? 2. whether I need to shape it hot or after heating or what? 3. whether and how to make it stiff again to impart spring yet durability? and 4. other considerations I'm not even aware of ??? (you don't know what you don't know!) Thank you, sir, for anything you can tell me or point me toward.

Best,

Sean

george wilson
07-10-2013, 2:56 PM
You can go to a model shop and buy music wire up to 1/4" thick in 3 foot lengths,to use on model airplane landing gears. You no doubt need something a LOT smaller. Also,at least in older cars,and likely in riding or push mowers,you can get "choke wire" which is also music wire. It is probably about the size you need.

I wouldn't try re tempering it,because it is so thin and quick to cool off,you can't ever get it into the quench before it has cooled. Buy the correct size wire and make a jig to bend it into the shape you need. You will have to experiment with grossly over bending

it before you get it right. I've had the problem in making thin leaf springs from .015" 1095 steel. The way to keep it hot is to lay it on a steel bar,and heat the whole thing up good and red,and dump the whole thing. The spring will be brittle as glass. Sand it clean carefully,and slowly heat it till it turns blue. Instantly dump it in the water quench before it goes past blue and turns gray,which is a soft,annealed state you don't want.

Years ago,when they were building the Jefferson Accelerator near here,I was asked to bend thousands of phosphor bronze(non magnetic) relay springs. Thankfully,they decided to go digital. I really didn't want the job of making thousands of those springs. But,I didn't want to turn them down,either,because I'd not be called on in the future to make things like nuclear targets,etc..

Sean Hughto
07-10-2013, 3:31 PM
Thank you, George!

Dave Beauchesne
07-10-2013, 9:59 PM
Buy the correct size wire and make a jig to bend it into the shape you need. You will have to experiment with grossly over bending

it before you get it right.
.

Sean: George has good advice ( as usual ) - at work a few years ago, a Millwright wanted to shut down our 40 ton overhead crane because the ' mouse ' ( snap ) spring was broken and the mouse was not functional - he was trying to be a jerk and I was his Supervisor. I went to the Machine Shop, grabbed a piece of about .75 mm music wire, chucked a 1/4'' bolt in the vise - I took out my Leatherman, grossly overbent the wire ( like George states ) put a couple 90* bends where applicable and popped it into place - took me less than 2 minutes and I had never done it before - pure luck, but I made the MW look silly without saying a word or rubbing it in, and he didn't even complain because I, as a Supervisor, wasn't supposed to do ' his ' work. My point is, If I can do it, you can do it, try it, you may make a mistake or two, but if you are like me, resurrecting something old is PRICELESS!! Good Luck - - - -

george wilson
07-10-2013, 10:50 PM
But,remember: My advice is only my opinion. Someone said my opinion was no better than any other!:)

Tom Vanzant
07-10-2013, 10:57 PM
Dave, somewhere there is a Marlin .22RF lever-action rifle with an ejector made just like your "mouse" spring. Bend, wrap, cut, assemble... it turned a non-shooter into a shooter.

Jim Matthews
07-11-2013, 6:49 AM
But,remember: My advice is only my opinion. Someone said my opinion was no better than any other!:)

That was just one schmuck, George.
He's outnumbered, here.

"It ain't braggin' if you can back it up..."
Dizzy Dean

george wilson
07-11-2013, 9:49 AM
Maybe he should get his wood working advice from a shoe clerk.:):):)

Shawn Pixley
07-12-2013, 6:18 AM
That was just one schmuck, George.
He's outnumbered, here.

"It ain't braggin' if you can back it up..."
Dizzy Dean

"If you can do it, it ain't bragging." -Satchel Paige

Satchel and Dizzy were unlikely people to connect. I suspect greatness respects greatness at whatever the distance...

Pat Barry
07-12-2013, 12:52 PM
Gee Dave, you probably didn't think it at the time but maybe you have since. Modifying a part like you did for a 40 ton overhead crane creates a huge potential liability problem. These days, if you did that, and there was an accident you would go to jail, at least in the court of public opinion, and there would be no acceptable defense.

Dave Beauchesne
07-12-2013, 4:25 PM
Gee Dave, you probably didn't think it at the time but maybe you have since. Modifying a part like you did for a 40 ton overhead crane creates a huge potential liability problem. These days, if you did that, and there was an accident you would go to jail, at least in the court of public opinion, and there would be no acceptable defense.

Pat:

There was a lot more thought and research went into the situation than the story I posted indicates.
Basically, I had talked to the crane company technician - no mouse spring was available for a couple of days, to which I asked what would you do? He was not available for a couple days as well.
' Make one out of piano wire ' ( or something like that ) was the reply. Since the mouse spring is not a structural part of the hook, and the load is not slacked off till the lift is complete, the inspection of the sling that is hooked to the hook is to be completed each time the sling is removed or attached.
The crane had been used with a broken mouse spring, and the Millwright was correct in his threat. However, the rationale was that the spring holds the mouse in place only, and load tension on the hook keeps the sling away from the mouse. Trust me, safety is very important to me and the people I work with.
My point was it is easy to make a spring with a couple simple tools and a bit of ingenuity.
Good point though, there are a lot of things that get done ( especially sine the proliferation of YouTube videos ) that make me shudder.