Re: Vacuum Bed

What size parts? What thickness material?

You can often do away with hole size and pitch by using mdf as your
cutting surface. Seal the bottom--except for the vacuum "entrance"--
and sides, and the entire table top become a low pressure area.

By placing non-porous material on the bed in areas where vacuum is
not needed, vacuum in areas which are, is increased...

You can do this with a shop vac, even. Details used to be on the
shopbot website. the main "detail" is that a typical wet/dry vac
needs airflow for cooling. So you want to be sure to have a bypass
valve which allows this.

If you're talking heavier duty apps (though the above works well
enough for commercial use), look at the regenerative blowers offered
by surplus sales of nebraska. This is what lies at the heart of
industrial systems. (They still often use the "mdf-is-porous"
approach though)

Hope this helps,

Ballendo



--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Dave Fisher" <dave@d...>
wrote:

> Looking to make a vacuum hold down bed for acrylics / wood etc.
>
> Any pointers to info or advice, especially on hole size and pitch
> and vacuum required would be appreciated.
>
> Rgds
>
> Dave Fisher UK