Buffy, i have one recommendation for you, if you dont mind, or even care
Sum it up in one word: Bodum
haven't had a ground go through yet
ofcourse i should say, french press is an art. You can't skimp on 2 things, you cant skimp on the press, because better quality presses have generally, better filters,, better quality materials that won't loose the heat, and now, Bodum has a double-blown line; and you can't skimp on the grinder, because a cheap rotating blade grinder will not produce the proper results, you may get away with it for pressure, and you may get away with it for drip, but in no way will you get away with it for FP (french press).
Start with the press, it's in how good your press is, and how you use it (oh boy, i know the comments coming)

But, ok, you say you like your coffee thick, which means that you likely get dark, bold roasts, for full-bodied coffee, and wait for like 5 miutes for it to get ready in a press. Thing is, first of all, the water you use, should have just been boiled, literaly under 25 seconds prior to the pouring it. Then you quickly mix the coffe with a wooden spoon, to get all grounds covered with water, and at this point you need to put in the top cap, in the snout closed position, because, at least with my bodum, it will prevent the heat leaving, really well. I leave my coffee in for about 4 and a half minutes, and it comes out perfectly, steaming hot, and almost at a drinking temp (little above).
second part, the grinder, if you don't get coffee pre-ground by the maker, i do, since i have no grinder, but you want a grinder that will give you a uniform grind, problem with blades is that it will create some big grounds, and also powder, and that is something your press does not like, and creates the grit. If your press uses a nylon filter, you may get away with it, but a proper, steel-mesh filter will alow some powder through, and is a lot more picky about the ground. I should say that the technique used for plunging is important. You tend to want to stay at a slow, steady rate, without forcing, steady plunge weilds less grounds. Lastly, you want to plung straight down, if you wiggle your hand too much, or get a bit of an angle going, you also risk grounds escaping...
As i said, i have had good luck so far, the new press is doing an awesome job, and so far the only time when grounds escaped, the press was being used by my dad...
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