Re: [CAD_CAM_EDM_DRO] Any "Best Practice" Recommendations for clearing chips and feed/speed when

Very interesting! Got any info on how a hobbyist could build one of these
"Coanda" systems?

Thermite made from aluminum and steel chips....hmmmmm. That should raise
some ideas!

> You need a regular dust collection system, not a shop vac. One of the

best, and

> easiest to build is the vortex system, (see rec.crafts.woodworking

archives).

> It's the same thing with grain silos; Enough fine particulate matter plus
> commutator/switch sparks equals instant explosion. There are several ways

to

> move the air into/from a dust collector, but you want a zero sparks

solution.

> One such solution would be to use an air amplifier. These work on the

Coanda

> Effect, which has to do with how gasses and liquids move across a curved
> surface. Coanda was one of those multi-discipline geniuses who lived back
> around the early part of the last century. His main gig was organic

chemistry,

> but he also designed, built, and flew, the first jet airplane. An air
> amplifier is a three opening unit that acceptss air from a compressor, and

uses

> it to induce an airflow into one side, and out the other. The specs I've

seen

> indicate that it works on a 1:25 ratio; I.e., a 10 mph flow from the
> compressor equals a 250 mph flow through the device. This spec is the

same

> from several manufacturers, so I presume this is the max for practical air
> moving devices, though no doubt the figures and sizes are different for

denser

> stuff like liquids.
>
> While I'm on the subject, try to segregate as much as possible the results

of

> your aluminum work from your ferrous metal work. Rust, (ferrous oxide),

mixed

> with aluminum oxide equals thermite, which burns, (redox reaction), in the
> neighborhood of 5 or 6 thousand degrees, and has been known to self

ignite.....

>
> Bill
>