[TheForge] Air Hammer Cylinder and valve combination

[magichammer]

Although it is a heavy investment for some of us, to me it was worth
saving up the $500 and buying the new air parts that Ron Kinyon
recommended in the plans in the first place, and here's why.......
Kinyon was a pneumatics engineer for GM. He knows his stuff and
he has already worked out all the bugs. At least 5 or 6 of us here in
southern Louisiana have built the Kinyon hammers using these parts
http://magichammer.freeservers.com/pdi_quotation.htm  and have
had no problems.
The chances that anyone is going to improve on Kinyons design are
slim in my estimation and the chances of less than great success are
high. We have all read posts here about what does and doesn't work.
If one saves money by buying mismatched surplus parts and they
give you less than desired results, then you haven't saved anything.
In fact you have wasted that money because you have to end up
buying the right parts later on anyway.
This is in no way intended to belittle the Mark Linn modifications.
http://afc.abana-chapter.com/
I have not used a hammer that uses his sistem so I cannot address it.
I do think however, that Mark uses new air parts as well, which is what
my point is all about.
dave m

----- Original Message ----- 
From: "Don Sinclaire" <sincla@telusplanet.net>
To: <theforge@mailman.qth.net>
Sent: Thursday, February 26, 2004 8:01 PM
Subject: [TheForge] Air Hammer Cylinder and valve combination


> Mark:
> I started building an air hammer a couple of years ago.  I used a surplus
12
> inch by 2-1/2 inch cylinder and a surplus 5-way valve.  The Ram is about
> 15-20 pounds.  The ports on my valve are only 5/16 inch in diameter by the
> time the hose barbs are screwed into the valve body.  Although the hammer
> went up and down, it could not strike a very hard blow. I planned to use a
> light weight ram and and depend more on speed than mass, since my anvil is
> only 150 pounds.
>
> It turns out that as the ram went down, it trapped too much air in the
> bottom of the cylinder, so that air cushioned the blow at higher speeds.
> The cylinder could not "exhale" fast enough. It worked OK if I reduced the
> stroke to about 5-6 inches.  I then strapped a 14-inch piece of rail to
the
> ram to add weight and it started to hit harder, but slower.
>
> I still check the surplus shop for valves from time to time, hoping to
find
> one with larger ports.  (A new one is a couple of hundred dollars.)
>
> Since you are using a relatively large cylinder, make sure you get a large
> valve.  You probably know more about that than I do, but I thought I would
> mention that.
>
> I would like to see a picture of the finished hammer.  Good luck.
>
>
>