The formula for the relation between spring-barrel & spring?

[B.B.B]

I just can't remember where, but I know I've read that there is a correlation between the width of the spring-barell & the length of the spring that fits to it.

This weekend I got a motor from a friend of a friend, who's no-brand portable I promised to try to fix.
No wonder it doesn't run. No spring in it. Well, there are shards from a spring. So at least I know that it should be 1" wide. And from a recent phone-call I don't think it has a governor either... But that is a later problem.

Does anyone know what I talk about here, have you heard of a formula for finding a spring of proper length. This barell looks very much like the one for my single-spring VV-IV.
And it measures 4" across.

[gramophoneshane]

I've never heard about such a formula, but it would be interesting to know if there is one & what it is.
I'm not quite sure how it would work though. Even if you could calculate the length, I don't know how you'd work out the actual thickness/guage of the metal??
Some cheap motors have springs that are paper thin, and then you've got the other end of the scale with springs like those found in Edison machines, which are quite a heavy guage & very strong (springy)

Is there any way you can post a picture or two of the motor?
Someone might recognise the motor & have a spare, or even just measure their spring so you know what size you'll need.
It could also help finding a governor. Very few governors are interchangable between brands, or even between different motors of the same brand.

[Brad]

I haven't heard of such a relationship either, but it does make sense that one might indeed exist.

If anyone would know, it would be the clock guys, whoever they are

[Shane]

From all the different spring barrels I've opened and looked at, it makes me wonder if a formula ever existed. The spring lengths of various brands and motor types seem to be all over the place. I've seen some barrels that have a massive empty space towards the center, while others are almost all spring. The spring thicknesses seem to vary by brand as well.

[B.B.B]

I did find the "Formula"
It was in Eric Reiss TCTM on the repairing spring section.

Unfortunally it didn't make me any smarter, maybe it's the language barrier or the beer consumed at the beach last few days, but he writes that as a guide-line "the new spring should when tightly wound make up about 30-40% of the radius of the spring-barrel". Makes no sense to me.
Feel free to mock me..

But like you all wrote, springs can vary greatly in thickness.
So a formula could, maybe, work brand-for-brand so to speak.

I had a problem awhile back, when ordering a spring for my VV-IV from a European dealer.
The spring I got fit great, without problems, but after a couple of playings, I started to get problems, the spring unhooking at the shaft & also being very hard to wind.
No wonder, after a LOT of hard thinking, I found out that it was almost a meter & a half too short..
Fit well, but still it didn't work...

As for this one, there is no need to try anymore.
I got the full story last night, my friend was at a Midsummernights-party (very big holiday over here) held by the man with the splintered spring.
Very late, they got an idea of going down to the beach, playing some 78s on his portable.
When they found out it didn't work, they decided to fix it.
Maybe not the best of ideas, at a beach, under heavy influence of brewed beverage, by two men used to work with heavy construction,
who never before have seen a phonograph motor.
When I heard the line "I remember we dragged an anchor up to use as an anvil" I knew this was going to the a tough one...

Anyway, when he found out the costs of a new spring, & maybe more parts & the work it will take, he decided that buying a new, off-brand portable would be much cheaper.

If it was a more wellknown machine, I would have considered to try to rescue it anyway, but this one just won't be worth it.