Canuck, my first batch took me about 15 minutes to mix, including smashing 30 acetaminophen tablets (inside an envelope) with an 8 ounce ball pien hammer.
I used the following:
250 ml 20% sodium sulfite solution
30 tablets @ 500 mg acetaminophen
20 g Red Devil Lye
The lye I used was from a new container -- if the container is airtight, it'll keep pretty well, but if it's lumpy it's absorbed water and/or carbon dioxide from the air and should probably just be discarded and replaced; it's only about $5 for a pound. And I used the sulfite stock solution because I already had it; you could just as easily start with warm water (say, 100 F) and dissolve 50 g of sulfite in it.
The solution will get warmer (in my case, by about 8 F) when you add the lye; add it gradually, with lots of stirring. And do use skin and especially eye protection when mixing; a droplet of lye solution (including the net 8% lye of the final concentrate) too small to notice immediately can cause permanent damage to your vision.
After everything is stirred, the solution will be very cloudy and chalk white. Seal airtight and let stand for at least 48 hours, 3 days is probably better. The solution will change to a light pink or tea color, and stratify into a darker, less chalky upper layer and a whiter, pretty opaque lower. Don't worry about the little rags and tatters of tableting material; they don't seem to hurt anything even if they get into the developing tank.
As you use it and allow air in, the solution will darken (just as Rodinal does). I've got a bottle that was mixed about 4 weeks ago, is the color of Coca-Cola, and works perfectly even at 1:100, same dilutions and times as Rodinal. No idea how long it'll last, but it is important not to filter or decant off the crystals that eventually form in the bottom of the bottle; those represent an excess of the p-aminophenol sulfonate over what's made soluble by the sodium hydroxide, and as such are the key to the hyperlongevity of Rodinal type developers. If the solution is removed from the crystals, the tiniest excess of sodium hydroxide will cause rapid oxidation of the dissolved developing agent and failure of the developer.
BTW, if you use distilled water at $1/gallon to make up the solution, it ought to cost you around 55 cents for 250 ml, but it'll cost about $17 to get started -- $5/lb for sulfite, $5/lb for lye, and $7 for 1000 acetaminophen tablets at Costco.
