Ed: In answer to your questions.
        Q1. For slab anodes count the face and edges at 100%, the side
against the tank wall is 50%. If your using baskets it's roughly 80% and 40%
respectively;type of basket mesh can also effect this #. For a common shared
anode take 100% of the area and divide by 2 for each side; use the 80% figure
for baskets.
        Q2. Anode current density is typically 15-20 ASF. Cathode current
density is 20-25 ASF.(These are assumptions I'm making for your plating
bath.) With these current densities you would have an anode to cathode ratio
of 1:1 to 1.5:1. This is true only if your cathode surface plating area is
always the same, which of course it always is :-) Take your best guess as to
what your "average" plateable surface area is and try to keep it between the
1:1 and 1:1.5 ratio.
        Anode spacing is about 8" face to face.

        Q3. Anode length is the same as or 1"-2" shorter than the racked
panels.If you are using bags on your anodes they can plug up with sludge on
the bottom, making the bottom inch or two of your anode ineffective.This
could be why you're getting different inputs on length.It can be overcome by
using anode bags 2"-3" longer than your anode. The sludge accumulates in the
bottom of the bag below the anode.

        Ed, if it's plating distribution you are trying to improve there are
many other items that can be looked at.
                                                Regards
                                                        Michael Barmuta
                                                        Staff Engineer
                                                        Fluke Electronics
                                                        Everett Wa.
                                                        425-356-6076

        We are currently doing some studies on our copper baths. Recently I
have =
been given some conflicting information/guidelines regarding cathode to =
anode surface area ratios and distances. Could someone please provide me =
with their preferences/experience to the following questions.

Q1. When calculating anode area, is only the surface facing the panels =
to the calculated or=20
       do you calculate the entire circumference?

Q2.  How much anode area should you have facing the panel surface area. =
The most recent=20
       information I have been given indicates you should have at least =
an equal or 1/1 ration.=20
       This would result in having at least  7- 21/2" anodes on each 42" =
bar or 3 anodes facing=20
       each panel with one anode in the middle.=20

Q3.  I have been told by some suppliers that you never want your anodes =
shorter than your=20
       panels yet I have recently been advised that my anodes should be =
about 2 inches=20
       shorter than my panels. I'm interested in getting feed back on =
this matter.

All responses will be appreciated.

Ed Cosper

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