Ron Kinyon comments on pneumatics

Richard;
Most hammers work well with the simple solution, one limit switch and a spring return
one pilot main valve.
On hammers of 12-16 in stroke I use, two limits, 2 pilot main valve
no center position. The dwell time between switches allows for full travel of the
stroke at a higher speed.
In flagstaff in 2000 I showed a one limit valve on a slide hooked to the foot pedal
Little Giant style hoop pedal.
Pushing the pedal all the way down would clamp the dies
If you use 2 limit switches make room for them to be moved manually in tandem.
I slide my limit to the top of its slide and use the hammer like a treadle hammer
because it can't make a full stroke.
I have not used the clamp mode much, most cases I am drawing out stock or using tooling
on the dies.
In most cases the tandem limits are on top of each other maybe a 3" gap
using the ARO small limit valves. I have used the Norgren 500 valves for 22 years
as the main valve and had only one fail in service.

what size cylinder and stroke are you using, what head weight?
Old style Kinyon or Mark2 with the beam?
Feel free to post my response.

Cheers

Ron Kinyon


-----Original Message-----
From: Richard Ferguson
To: ron kinyon
Sent: Sat, Apr 2, 2011 10:18 am
Subject: Hammer - pneumatic questions

Ron:

I asked these questions on the iforgeiron.com website, and no one had an answer.
Somebody sent me an email suggesting that I ask you those questions.

If you go with two limit switches, do you then buy a three position valve? I
think that you can buy two position valves with two pilots and no spring, or
three position valves with two pilots and a spring center return. The three
position valves might have all ports blocked in the center position, is that an
advantage? Why? Would that conserve air? If you only had a two position valve,
what is the advantage of the two pilots with two switches vs. a single switch
and a spring return?

I can see that two limit switches provides a bit more flexibility. Having the
limit switch position tied to the treadle in some way adds complexity, but some
advantages as well.

No matter what arrangement you use, would you still need to manually adjust the
limit switch position if you wanted to use taller tooling, at least if you
wanted full power with taller tooling.

I would of course appreciate any comments. With your permission, I would post
your answer on the site.

Thanks,
Richard Ferguson