neilfj, thanks again.
Regarding temperature, I've been working from Caswells plating instructions. For the earlier, non-LCD, method they list a range of 65-80º, w/72º being optimal, so I fudged a bit and figured 82º would still give reasonable results. In the LCD specific instructions, they only mention the 70-72º optimal temp., but I presumed the range would be appropriate to both methods. Is the temp that much more critical w/LCD?
I had also assumed that one could manipulate one or more the variables to compensate for others that were not w/in range. e.g., if the temp were higher than desired (softer, open pores), you could run at a higher current (harder, closer pores), and the 2 results effectively cancel each another.
I've also realized I have a natural chiller. Over night temps still drop to 55º here in the northwest, so I'll just set the bucket outside one night, and run the test in the early morning after (the obvious is always the last thing you think about!).
Regarding the connection, I think you've misinterpreted the photos, and I could have explained it better. If you look at photo 4, right side, the 1cm.sq. area centered on the hole is the only connection spot. As you can see, this area is clearly delineated by the dye. Electrolyte did creep up the sides, but the connection point itself shows no anodize growth, still has 100% continuity, (w/in 0.1 ohm, see my next response to fibergeek), and absorbed no dye whatsoever. The aluminum connector itself shows similar characteristics. The exposed surface did get some wetting by electrolyte, and did take some dye, but the mating surface is clean w/ full continuity. So I have to presume the connection was good. I'll try something different next time.
I used the 4.5 amp/sq.ft. because it is recommend as the best compromise between hardness and dye absorption. Caswells recommended range is 3-6 amps, with the lower giving softer, open pores, w/more dye absorption, while the higher current gives the harder surface at the expense of dye absorption. I might have to try a higher current density as you suggest.
re: the unknown alloy: isn't that always the case w/hobbyists? The "real life" parts that I plan to anodize are of unknown alloy, and since the manufacturer has been defunct for 40-50 years, there's no way to find out. I just have to wing it here, and try to get an acceptable test finish and see how it works, then try the real piece. The "real" piece(s) are of cast alloy tho, so I need to find something similar to test with first.
Thanks for your help.
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