Re: Van Norman #12 Milling Machine

PTENGIN@... wrote:

> From: PTENGIN@...
>
> In a message dated 01/23/2000 8:26:26 PM Hawaiian Standard Time,
> jmelson@... writes:
>
> << Unfortunately, those would be BIG gas springs. Maybe, one could come up
> with old oleo struts from aircraft landing gear. That would be about the
> right size.

> How do they keep the force more or less constant on those gas springs? I
> also considered pneumatic cylinders. However, like a regular spring, the rate
> changes depending on where in the travel you are.

They have a larger, outer tube, that makes a gas tank, essentially. It is
just slipped over the actual cylinder, and welded on. There are holes at the
desired point that allow the tank to connect to the top of the cylinder.
The piston rod generally comes out the bottom, but I've seen them done
both ways.

> I considered a regulator
> but then you need a compressor to admit when low and the regulator to dump
> when over pressure. Maybe if we got a really large cylinder and ran low
> pressure.....

The only problem with this is that the machine will drop, by itself, some
hours after the compressor is shut off. Not a good idea. Relieving regulators
are no big deal, most of mine are. But, most of them will do funny things
when the compressor is shut off.

Jon