|
Letter 41056
Chroming plastic and other non-conductive
substrates
++++++
Hi, Keith Burwell here with a polish and plating shop in
Riverdale, GA. We do mostly bumpers and exterior automotive metal
trim. We have recently been swamped with request for plating plastic
and fiberglass automotive parts. I am familiar with the spray-on
products that are offered through Alsa and Spectra, however I am
interested in the copper nickel chrome plating process. Herein lays
the problem: finding a copper base which will clean in Caustic soda
and take a cyanide copper / copper strike. I have tried a couple of
copper and nickel EMF (electro magnectic frequency) type "paints" to
use as a base using ethanol to clean the part prior to plating. The
copper paint produced great conductivity but unfortunately rubbed off
as soon as my glove touched it. I know there is a process out there
as I have seen the end results ...just can't find any information on
it. Any help would be greatly appreciated.
Keith D. Burwell
polish and plating service -
Riverdale, GA, USA
++++++
Though most substrates can be plated, not every plastic or resin
holds the plate well. It`s a matter of adhesion. ABS was designed to
provide the best attainable bond by means of a blend of three resins
(Acrylic+Butadiene+Styrene) one of which (B) is in form of globules
and dissolves during the pre-treatment leaving pockets that will act
as counter-locks once the plate is built up. In any case, some sort
of mechanical lock is always necessary when dealing with plastics
because they do not have the bonding affinity to the plated metal
that metallic substrates do. Look for Plating on Plastics or POP in
this site.
Guillermo Marrufo
Monterrey, NL, Mexico
++++++
Dear Mr. Burwell
Plating of fiberglass is much known in Egypt, but unfortunately
preparation of substrate should start in molding stage not in plating
shop.
You ask the factory to added some carbonate {CaCO3}
To the resin before molding then etched in any acid e.g. H2SO4
carbonate will dissolve and you get a good whole which is very
important in providing the good adhesion the same role which
butadiene play in ABS.
Kindly note the attached photo to one of our products made of
fiberglass it is nearly in the same size of yours.
  
GOOD LUCK,
Raafat Albendary
- Cairo, EGYPT
Dear Reader, please --
- Answer or follow-up on this
subject (in non-commercial
fashion).
-
- My company is a supporting advertiser at
finishing.com and we want the contact information to reach
the inquirer privately.
-
- Post a
new question or inquiry on a
different subject.
-
 |