[TheForge] ALT Treadle Hammer Springs

[Jeffrey Polaski]

Just thinking out loud... does anyone know if anyone has used air shocks
off a semi truck/trailer? I bet those things would make great springs.
They'd certainly be easy to adjust.  I'd hate to pop one, though --
you'd have to make some sort of cover to keep hot metal away from it. 

Jeff Polaski

-----Original Message-----
From: theforge-bounces at mailman.qth.net
[mailto:theforge-bounces at mailman.qth.net] On Behalf Of Peter Fels And
Phoebe Palmer
Sent: Tuesday, March 20, 2007 12:52 AM
To: Sponsored by ABANA
Subject: Re: [TheForge] ALT Treadle Hammer Springs

Neat idea Paul!
One could use a big hairy old cylinder for the guides and it's 
piston for the tup.
The only problem i can see would be overcoming piston ring friction.
Having gone that far, might as well add a pressure release valve 
to the treadle...grin...pf

paul wrote:
> Some years ago while bench forging, the blacksmith equivalent of bench

> racing in gearhead circles, I suggested that an air spring might be a 
> good way to replace the springs in a treadle hammer. Steve White of
UMBA 
> had a treadle hammer that used a 6" or 8" steel pipe for the backbone
of 
> the hammer. Since the pipe was sealed at both ends it made a perfect
air 
> reservoir. The idea was to use an air cylinder in place of the spring,

> and connect that to reservoir with a volume about 100 times as large
as 
> the displacement of the air cylinder. When the system is inflated to a

> sufficient pressure to raise the hammer, the force to move the hammer 
> would not change much on the down stroke, as the volume of the air 
> reservoir is many times that of the cylinder. Steve reported that it 
> worked. I don't know if he is still using this system, but it might be

> worth considering. By supplying the reservoir with a small air
regulator 
> you can adjust the force required to move the hammer head, and by 
> diddling the ratio of the two, cylinder to reservoir, you can alter
the 
> increase of force that is required to move the hammer throughout its 
> range to suit.
> 
_______________________________________________
Manage membership or unsubscribe at:
http://mailman.qth.net/mailman/listinfo/theforge
theforge mail list group photo site is
http://www.photoaccess.com
Login:  blacksmithblacksmith at hotmail.com
password:  anvil
___________