Re: [rp-ml] static discharge from beadblasters

From: Jeff Demand <jdemand_at_gmavt.net>
Date: Fri Jul 17 2009 - 22:46:26 EEST

Nick,

I haven't used a Trinco machine but still remember the electrifying
experiences of years ago.

Googling "sand blasting static" turned up the following
<
http://en.allexperts.com/q/Industrial-Health-Safety-3630/2008/2/sandblasting
-static-electric-shock.htm >
         
     
<SNIP>
"Answer
Hi Melinda the static you are receiving is caused by the friction of the
grit on the product and on the insides of the cabinet, the friction creates
static build up which when at its peak discharges itself by the route of
least resistance, usually you, your body acts like a capacitor and stores
the static until you touch an earth, also you may be using a rubber pipe
inside the machine to deliver the grit, this insulates you for a while
until you touch the metal of the cabinet, then crack you get a shock. It is
difficult to find a solution with the information you have provided but I
will suggest some controls to try out.

Earthing the cabinet to a copper pipe could work yes, but you are the
source of the stored electricity, you could try a static body strap which
you attach to your wrist or ankle and then to the machine body this will
continuously discharge the static before it builds up to a painful level.
Standing on a metal plate wired to the body of the machine could also work

The material of your shoes could insulate you sufficiently to allow static
build up also, try thin plastic soled shoes rather than rubber, (bare feet
would cure it but exposes you to other hazards).
Any of these should work but if not contact the manufacturer of the machine
to see what they suggest. Be sure to have any alterations you make checked
by a qualified electrician as well."
</SNIP>

You could also talk to Trinco, I'm sure some of their other customers have
the same problem.

jeffD

*********** REPLY SEPARATOR ***********

On 7/17/2009 at 9:59 AM Nick Rivers wrote:

>Hello,
>
>Our company does SLA cleanup with a Trinco dryblast with 170 glass grit
>and since we bought this metal box we're getting some fairly severe
>shocks. Our attempts at grounding have been unsuccesful. Anyone have any
>suggestions. Thanks!
>
>Nicholas Rivers
>Nuhill Technologies, Inc.
>8600 Xylon Ave N. Ste. 107
>Minneapolis, MN 55445
>

-
Demand Designs
Analog/Digital Modelling & Goldsmithing

http://www.gmavt.net/~jdemand
jdemand@gmavt.net
-
Received on Fri Jul 17 22:36:08 2009

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