Guitar sting in a shutter (spring replacement)?

[svlindbe]

(It should be a "Gutiar STRING", of course! Sorry!)

I tried to repair an old Supermatic no 2 shutter the other day. One small spring was broken. It was one of those made of thin wire. Spare parts are scarce, so I thought "where can I find something similar"? After some thinking, I came up with the idea of using a guitar string. Obviously, it must be a metal string, not the nylon/plastic ones! On the other hand, a used string will do the trick. I took one, held it with a pair of pliers and bent it sharply twice around a small pin. It turned out to be a little stiffer than the original in this case, but it seems to function all right. Now I just have to get the entire shutter back together and see if the times are correct. Assembling is way more difficult than with a Compur or Compound....

I just thought I would pass on the idea. Use it if you need it!

Svein Lindberg

[Peter K]

Svein, be careful with too strong springs because bearings etc. can be damaged very easily.

[Nathan Smith]

Perhaps you should switch to extra-light strings!

The new coated strings last longer before they go dead

[Glenn Thoreson]

Yeah, but now all your pictures will be in the key of E.

[Nathan Potter]

Piano wire is another good source for spring material. Comes in various sizes from .001 inch to .025 inch. Look for Small Parts Inc., Miami FL. The all time, drop dead, material is Elgiloy wire made originally by the Hamilton Watch Co. - of course for watch springs- but I don't know of any sources presently.

Nate Potter, Austin TX.

[Jack Dahlgren]

Nathan,

Elgiloy is from the Elgin watch company, not Hamilton. Hamilton was their competitor. I think Elgin is out of business but the metals part continues here:
http://www.elgiloy.com/index.html

For a simple spring (piece of wire) piano wire or guitar string are probably fine. The need for special alloys which don't change dimension with temperature is for the coiled main springs which must behave identically several times a second for years at a time.

[Jeffrey Sipress]

I've wound hundreds of springs from piano wire or guitar strings (same thing). You never get the perfect one the first try. Experiment with different diameters and number of turns. if it's close, you can anneal the material with a small flame, but just a bit or it goes full soft real quick.

[svlindbe]

If it's close, you can anneal the material with a small flame, but just a bit or it goes full soft real quick.

Does that mean that one would likely be able to weaken any similar spring with heat if needed to adjust it to the task?

Good to see that others have found sense in using instrument strings for springs. One very good thing is, as you point out, that the availability is good, and they can easily be found in a vast number of types.

Svein L