Re: [CAD_CAM_EDM_DRO] Re: Counterweighting the Z axis ?; Power off position holding ?

I've had good results with two 150lb gas springs from McMaster Carr. If
you look in the photos section for " NEMA 42 - Gas Springs" you'll see
how I fitted them to my knee mill. The knee is raised/lowered by a ball
screw. With power removed, the knee always stays where it is. You may
be able to adapt the same general idea to your machine.

My machine doesn't look as clean now as it did in Feb 2002... Plus it
has since been converted to servos for faster rapids.

Cheers, Peter

Kim Lux wrote:

>Glad to hear I am not the only one.
>
>The problem with springs is that their force varies with where the head
>is. Maybe they could be adjusted for zero force in the home position.
>That wouldn't help for an EStop though.
>
>A regulated air cylinder could give a constant force with any position,
>but I'm worried the air dynamics would mess up the head motion.
>
>So far the best solution seems to be to counter weight it and/or apply a
>bit of drag to the ballscrew drive.
>
>Kim
>
>On Tue, 2003-07-08 at 08:46, tsalaff wrote:
>
>>Kim,
>>
>>I'm dealing with the same problem right now although my Z axis is only
>>40 lb.. Going to try making brackets to anchor support springs. Will
>>report on how these work.
>>
>>>motor the milling head will slide down the column as soon as power is
>>>removed from the servo.
>>>
>>>Kim Lux <lux@d...>
>>>
>>
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