Model Engineers’ Workshop – August 2019

54 http://www.model-engineer.co.uk Model Engineers’ Workshop

systems, including corona and triboelectric,
is to use domestic ground connections
found in the home electrical circuit. A 3-pin
plug is used and has the live and neutral
pins removed, leaving only the ground.
This ground is wired to both the gun and
the work piece using crocodile clips to the
workpiece and crimp bullet connections to
the gun, photo 9.
If you are adopting this method, it is
necessary to do a safety check on your
outlets. For £10 or so it is possible to
purchase a plug-in socket tester which
will confi rm that your domestic ground is
actually functioning as it should. For all my
ground connections I have used 16 gauge,
1.5mm cable. This may seem excessive, but I
have had no ground problems.
Water and gas pipes do not make good

grounds. There are too many sections of

plastic pipe in modern systems to enable

good ground connections.

The second method is to buy a 2 metre

copper grounding rod which is literally

hammered into the ground. This can then

serve as a dedicated grounding point for all

of your powder coating eff orts. An outdoor

location with damp soil will provide the

best ground. This is the preferred method

and provides an excellent ground. I used 16

gauge stranded wire for a robust ground

system and found that this ground rod

produced notably better results, photo 10.

If it is a dry hot summer, or if you live

in the desert, a bucket of water poured

on the earth around the rod will improve

grounding too.

The concept of “ground” can be

confusing. This is because the same word

6 7

8

9

Wiping down with acetone removes all
traces of oil.

Heavy items can be well supported on the rack.

Some items are best suspended from the rack

Plug and cables for domestic ground connection.

Fig.3