[SEL] More springs

[jbcast at charter.net]

> This is pure speculation but is it possible these barrel shaped springs 
> are not would on a mandrel at all?
> 
> Being in the copper rod casting business I have the opportunity to go to 
> the annual wire show on occasion. There are all kinds of equipment there 
> designed to process wire the thickness of a hair to as heavy as 2" in 
> diameter.
> 
> One of the machines I am most enamored with is used to make thinks like 
> coat hangers and other wire product shapes. Wire on large spools is fed 
> into the machine via strong  feed rolls. The wire is fed out of a 
> central iris. Around this iris are rollers, blocks and other forming 
> tools. Imagine this wire being fed out and there is a tool on one side 
> slightly in the path of the wire which is trying to go straight. The 
> wire will hit this tool and will be pushed to the side. Now the wire 
> will no longer travel straight out of the iris. In fact, depending on 
> the amount of interference the wire will curl and for a perfect circle 
> that will wrap back on itself. Now if you move this tool off of 
> centerline a little you will still form a circle, but it will not wrap 
> back on itself but rather it will form a helix. Keep pushing the wire 
> out for a dozen rounds and voila' you have a spring formed without the 
> use of a mandrel.
> 
> Now if you can make an adjustment to how far the tool is moved in and 
> out, in otherwords control the amount the tool is pushing on the wire, 
> then you should be able to vary the radius of the curve being formed. 
> Push the tool in to form a tight radius, pull it out to form a larger 
> radius, and then back in again to make the tight radius again. Now you 
> have made a barrel spring.
> 
> Just my 2 cents for what it's worth.
> Curt Holland

 Thanks Curt, this is how probably how they're produced today, I think Steve W. has an earlier machine.
J.B.