[Homestead] Making jewelry, electroplting it.

tvoivozhd tvoivozd at infionline.net
Sun Feb 13 14:56:33 EST 2005


tvoivozhd---I wouldn't ever voluntarily wear jewelry---not even military 
class ring when flying military aircraft---considered it a very good way 
to lose a finger in bailing out or in my numerous crashesl

Which is not to say it is isn't a good business---I made the tooling for 
coin bracelets and got the cost of chromium and gold plating down to 
such a ridiculous level that my partner Karl Holston and I had to make 
money in a corner of his welding shop. Had some beautiful literature 
that we got cheap too---must still have a few copies still around and a 
few bracelets too.




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Electroplating
Student's name: Bob
Grade: 10th
School: Outside of USA
Category: Physical_Science.Chemistry
Expert: Mark G. Forbes

 > i need to electroplate a leaf with silver. I needto know how to
 > electroplate carbon or graphite on to the leaf before i electroplate the
 > silver please help!!!! Need reply within 2 days

I presume that the leaf is relatively stable, so it can withstand modest
amounts of handling. I think I'd experiment with a sooty flame, maybe
like that produced by burning acetylene or "moth balls" in air. I don't
know if you'll be able to coat the leaf with soot without setting it on
fire in the process, but it's worth a try. Use a "test leaf" to get
your technique right, before you do it with the "real" one. You won't
be electroplating the carbon....that's just applied as a coating 
mechanically
to provide a conductive surface, then the silver is electroplated over it.

Another substance you might try is copy machine toner. It's mostly carbon
black, with a plastic binder. You might find that just dipping your leaf in
the toner (you can use the waste stuff from the copier) will work. Again,
test it out on something first.

Your local electroplating shop may have some other ideas, and if you've got
a university nearby you should see if they have an electron microscopy
department; those folks generally have to coat their samples with a 
conductive
surface before they can use their microscope, and they have ways of doing
this. If your leaf is still fresh, freezing it solid first may make it 
easier
to work with.

Good luck!
MGF


http://www.seps.org/oracle/oracle.archive/Physical_Science.Chemistry/2001.02/000982317712.12499.html
(electroplate maple leaves with brass, then gold--may freeze them to 
make them stiffer)


http://www.dalmar.net/electroforming.htm
(electroforming over leaves, ceramics)


Warning---most plating chemicals are very dangerous---wear protective 
clothing and be supercareful---vent room AND DON,T BREATHE THE FUMES.


Difference in Plating

Understanding the Difference Between Brush and Tank Plating

Brush plating is a very useful and portable method of plating. Many 
different types of metals or alloys can be applied over another metal. 
Our company makes far more solutions available in brush plating 
chemicals then tank plating due to the large demand of our customers. In 
a brush plating set-up we can work with lower powered rectifiers and 
much less chemicals then in a tank plating set-up. Larger pieces can be 
plated at a lower investment money wise and a smaller work area is 
needed. Basically it doesn’t matter how large the piece is, since it 
will plate wherever we touch the wand to the work surface. Tough jobs 
can be done easily since we do not have to disassemble most jobs. Car 
parts can be plated right on the auto without dismantling the car. This 
is how the gold emblems on cars are done. The emblems are never removed 
from the car to be plated. It doesn’t matter if we touch the paint on 
the car as the paint does not conduct electricity so the paint will not 
plate. Guns are much easier to plate this way as there is no worry of 
the insides getting rusty from submerging them in solutions. If you have 
two conductive surfaces close to each other and you only want to plate 
one of them, the plating will only occur on the surface that you contact 
with the wand. If it is impossible to plate one area without touching 
the surrounding areas then you can mask off the area with tape or nail 
polish or the such. In brush plating the solution is all used up and 
therefore you do not have a disposal problem like in tank plating. It is 
considered environmentally friendly.

The theory of Brush plating is simple. The rectifier supplies a negative 
charge to the work piece and a positive charge to a hand held wand which 
has the anode attached to the end of it. The anode is covered with an 
absorbent material which holds the plating solution. The anode can 
either be dipped in the solution or in some large jobs the solution is 
constantly pumped up to the area being plated. The anode is then applied 
to the work piece by the operator, or the work piece can be moved under 
the anode, such as a moving shaft. The movement will apply even plating 
on the entire area being plated. Plating occurs only where the anode 
contacts the work piece.

Advantages of Brush plating: Lower initial cost to start. Portability, 
the equipment can be moved to the worksite. Ease of operation. Permits 
the plating of parts too large for a tank. Reduces the amount of 
masking. Reduces waste disposal. And don’t let the word brush fool you, 
you can’t leave any brush marks since the metal is electrically 
deposited on the work piece.

In a tank plating set-up we must have a tank of sufficient size to hold 
the work piece with room for the anodes and at least 3 to 4 inches of 
space on each side. Jewelry and small car parts are a good example of 
items that take well to tank plating, and the tanks can be as small as 
one quart size in some cases. In electroforming which is the plating of 
non-conductive items, a tank system must be used first to apply the 
copper over the conductive paint. A tank has the advantage of being able 
to build-up thicker plating without you being there or doing any labor 
during this step. With most solutions the anodes must be equal to or 
greater than the work piece. If we use anodes of the same metal as the 
solution then basically the solution goes on but the anodes dissolve and 
must be replaced. When using stainless steel anodes the metal is used 
out of the solution but the anodes don’t wear out. The solution is then 
replaced.

Advantages of tank plating: Easier plating of complex shapes. In most 
cases multiple parts can be plated at one time. In electroforming the 
copper must be tank plated over the conductive coating. In some of the 
tank solutions the brighteners, which are chemical additives can save 
you some of the time and labor of polishing. The pieces plate out bright.

Similarities in the two types of plating: The finished product is the 
same if the plating is done properly. In our showroom you can not tell 
the difference between the two. They are both deposited on the work 
piece and electrically bonded just the method of applying it is 
different. In tank plating the thickness is determined by how long you 
leave the item in the tank to plate. In Brush plating the thickness is 
determined by how many times you go over the surface of the work piece.

Differences in the two types of plating: The plating chemicals used in 
brush plating are much more concentrated than the solutions for tank 
plating, therefore they are not interchangeable. In most cases there are 
approximately 15 times more metal in them. It does make them more 
expensive per ounce but they also cover much more area than tank 
solutions. The nice part is that you don’t have to buy such large 
quantities of solution to do the job. Also because of their 
concentration the brush solutions can build-up thickness faster than 
tank solutions.

Electroforming: In electroforming we start with a applied conductive 
coating and plate with a special copper solution in a tank. The next 
coatings can either be done in a tank or by brush plating but the first 
plate of copper must be done in a tank.
Home Important Information Difference in Plating Plating Machines Tank 
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http://www.google.com/url?sa=l&q=http://www.metal-plating-chemicals.com/&ai=Bw6et8qYPQtD3PIyaaMfhiY0Pm9G6CNGupgHDyIQGoI0GEAYYBigIMAE4AEixOZABDpgBg0vIAQE&num=6


http://www.jaderockshop.com/BOOKS/BK2A.htm





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