why use wire mesh or drill holes in plates?

[BlackSheep]

i understand that it increase active plate surface area, but if you think about it, it decreases total volume too, right? for example, if you had 16 guage steel plates and drill 180 1/18 inch holes in your plates, you have 10 inches extra active plate surface area, but thats also 10 inches of metal lost and you would have to run your unit at a lower current, wouldnt you?

[D.O.G]

Using perforated plate instead of solid plate may allow more current to flow in the cell. However, I don't believe that this is due to any "greater surface area".

Have a look at the edge and tip effect at any site like this one.
http://electrochem.cwru.edu/encycl/art-d03-curr-distr.htm

Each hole presents another edge to unbalance the current density within the cell.
The 0.5A per 0.5" of plate surface rule-of-thumb, presupposes a uniform plate surface, where the current density is spread evenly across the surface. The more edges present, the more high and low density spots across the plate surface and the more uneven the gas production.

Yes, perforated plate seems to allow more current draw, but I think most of that extra current is "wasted" as in any wet cell and not being used for gas production.

[BlackSheep]

so.. all in all, perforated plates are bad?