Use coffee filters, I don't think cloth from jeans or a t-shirt is anywhere near fine enough (except for a 1st filter).
Coffee filters are cheap...should be easy to find.
Agreed with hood - micron filters (probably) wouldn't work. Paper coffee filters - here in Australia they sell em in supermarkets for a couple of bucks for 50 or something.
To use coffee filters - you wet them before putting one in a glass or cup (or simar container). Pour your sloppy dissolved pill gunk into the moist coffee filter and it will slowly drip into the glass below. May take a bit longer, but is much finer - and presumably safer than using fabric to strain through. Undissolved particles of paracetamol could concievably be getting through without being completely obvious to the eye (it is assumed that the white stuff is paracetamol - but it
could be chalk and other ingredients; it is hard to know for sure.
Also, regarding your DHC extractions that aren't coming out 'clear' - remember that "CWE" =
cold water extraction.
The point of the cold water is that the paracetamol is far less soluable in
cold water than in warm or hot water.
If you are using warm/hot water to dissolve the pills, you may be dissolving more than just the codeine/DHC into the solution.
In theory, I guess cooling the warm water with the pills dissolved in it will precipitate out the paracetamol - but I don't know how effective (or true) this actually is.
A safer method is to
not use hot or warm water to start with - but to use cold/chilled or even cold tap water to start with. This will dissolve less paracetamol into solution to begin with, and you're not relying on it condensing back into a solid when you cool it back down.
It might take longer to dissolve the pills in cold water - if this is a problem, crush or grind them first.
While solubility of codeine/dihydrocodeine and paracetamol/NSAIDs in varying water temperatures is known, I'm not sure if any scientific data exists on the safety and efficiency of different cold water filtration techniques exists (such as using warm water, then chilling it).
Personally, I would use cool/cold water to start with, just to be avoid dissolving unwanted pill contents to begin with.
And a good filter (lab is best, but coffee filters are considered to be adequate - and far safer than clothing fabric.
It's not worth risking liver damage from ODing on paracetamol. Get some coffee filters: