(snip)
Well, if you want to ping my e-mail with a mailing address, I'll mail you about a cup of the straight sodium borate pentahydrate that I have (though it might be decahydrate by the time it gets to you).
(snip)
Sounds like you are doing fine then. (Yeah 100# tanks are a lot nicer to use.)
(snip)
Mixing it at about 3 parts water to 1 part ferric chloride seems to give a lot of people a fast and fairly clean etch.
Good luck. (now I just need to get my power hammer finished...)