Re: plating xmas balls

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Robert Jones" <alwynj48-at-earthlink-dot-net> 

Hi all,

Thanks for all the responses.

I now think with that with stainless-steel globes avaiable at about $20 buck
for about 8in thats the way to go.

  A suitable process may still have some purpose.  After reading the replys
and a bit of research I would suggest two simple methods.

1. Zincate (dip in sodium zincate made from zinc and sodium hydroxide) the
aliminum. Possibly done twice with an acid etch in the middle. Then plate
with acid copper sulphate.  No hard to get or nasty chemicals cheap and only
copper for the anode. The problem is the aluminium may be too thin and the
copper tarnishes easily. Also sutiable for solid allumium zinc and steel.

2. Graphite or conductive paint followed by acid copper sulphate.  I tried
the graphite method many years ago and found it tended to lift off as the
object was put in the plating solution. It may have been a cleaning problem.
The conductive silver paint would seem to be a good bet but the 1cc bottle
they had at RS were $15 each from memory. Again the copper tarnishes easily.
The graphite method does work on wax perhaps it sticks better to wax. Then
just coat with a solution of wax in say paint thinners and allow to dry.

Perhaps the zincate can be applied with plating to copper to prevent tarnish
.  That may be good for a cheap way of protecting a copper pipe primary ie
only requires sodium hydroxide and  zinc and zinc for the anode.  A similar
passivation uses sodium stanate,  perhaps made by desolving tin solder in
sodium hydoxide and would only require a tin solder anode.  Again readily
available cheap and not nasty chemicals. Appently this deposites tin and can
be soldered.

Bob



----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Wednesday, December 10, 2003 7:00 AM
Subject: plating xmas balls


 > Original poster: "Robert Jones" <alwynj48-at-earthlink-dot-net>
 >
 >
 >
 > Hi all,
 >
 > Xmas decorations now fill the shops. I have seen silver 8-inch diameter
 > globes, which are probably aluminum coated plastic. Discharges strip the
 > coating. Now if I could metal plate one it may make a nice topload for a
 > small coil. I know its possible to plate almost any metal on any other but
 > some processes require nasty chemicals. The only simple solution I could
 > think of was ammoniacal copper. It will deposit copper and will not
disolve
 > the alluminium. Anyboby else got any suggestions involving readily
 > available chemicals and anode material. Chrome would be nice.
 >
 > Bob
 >
 >