Kerik
I used to buy mine from Geof Catherines at Derby University. But as his
price went up to well over a pound a gram I now make my own using the
peroxide version of the recipe in Dick Stevens' book. This gives 500ml of
a twenty percent solution for an initial cost of around five pounds plus my
labour. This compares with a cost of three pounds 50 a gram in the Alpha
catalogue.
When Geof sent the first order he included some ferric oxalate which had
been made six months earlier to see if it still worked.
It was still working two years later.
You say that you add EDTA and oxalic acid to the Fe3. In the interests of
simplification I tried leaving out theoxalic acid, this is the first I have
heard of adding EDTA, I can detect no difference in tthe final print.
Terry.
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