I just mixed up my first batch from PF. The directions for part B say to add the 100g potassium carbonate to 75ml of water, then add water to make 100ml. Once I added the potassium carbonate I could not get it to desolve all the way, plus the total volume was over 100ml.
I then found the recipe on http://unblinkingeye.com/Articles/PC-HD/pc-hd.html uses 100ml of water to 100g potassium carbonate. So I added 25ml of water and it all desolved.
Which is right?