Hello Timothy,

I've forgotten more than I know about copper plating but purely from a 
practical viewpoint your problem is more likely to be in the copper solution 
unless the rectifier has lost a phase. It is possible the brightener level is 
too low and you are getting high CD nodules.

I don't think nodules would arise but it is not good practice to load the panels 
without any strike voltage and you should modify your programme to start at 
0.75volts with ramp up to full plating voltage. If your connections and anodes 
are working properly, the voltage should not exceed 3 volts at 500 amps. I 
expect to see volts between 1.5 and 2.5 to achieve 300-500 amps and if it starts 
to climb, there could be problems with insufficient anode area or bad 
connections. 

Filtration needs to be good to prevent a build up of particles which can cause 
nodules. This would be more widespread and not restricted to high CD areas.(I 
assume your anodes are in bags). Your copper solution supplier should have the 
answers, and if not you should be looking for one that has.

If you find the answer I would like to know what it was.

Good Luck and Merry Christmas
-- 
Paul Gould
EMail [log in to unmask]

In your message dated Wednesday 18, December 1996 you wrote :
> We have been exhibiting miniature size nodules on our panels for quite
> some time. These miniatue nodules resemble a slightly high brightner
> burn. 
> 
> My questions if anybody could help are:
> 1. Would a rectifier with too high ripple affect the leveling of copper
> plating?
> 2. We currently hot load our racks into the bath, the program is set up
> with a five second lag  and raises from 0 amp to calculated amperage. So
> the panel sees 5 seconds of 0 amps before the rectifier applies voltage.
> Could this be a contributor? 
> 
> Timothy Gaylor
> 

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