iso wash is great for cleaning, but I always had trouble reclaiming the leftover goods.
when I go to salvage my kief and clean my grinders (before the occasional iso wash to get rid of the smell) I always use a grinder brush. It's just like the ones that come with electric razors, looks something like
it'll hold onto a TINY bit of your kief, but it can salvage 99.9% of it if you're smart about the order in which you brush each compartment. You want to go from the top down, so that the kief constantly falls to a lower compartment, until it's finally all in the bottom chamber, ready for you to scrape into a ~1g-sized pile.
Now that I think about it, I'm sure even a clean paint brush would work. You know, one of the tiny watercolor ones.
As a final thought, if your grinder's been so caked up for so long that the kief's turned to low-grade hash, a brush is
not going to help. In that case your only options are to handscrape the grinder, which is a pain in the ass I've gone through before, or to just go through the iso wash once or twice. My problem was always using too much iso and too broad of a drying dish, so it was almost pointless to scrape by the time it was done drying.
That's what turned
me off from iso-wash to reclaim, but don't repeat my mistakes and you should be fine.
*Just saw your last question. Yeah, you could submerge it in a jar, but that would use a lot of iso. I liked to put mine in a ziplock bag, and try to just fill the interior as much as I could before closing it all tight (still in the bag). Seal the bag, make sure it stays that way and give it an occasion light shake. Try to keep it upright and any iso from leaking through. You can do this for as long as you like with the occasional shake, and your results will vary per wash depending on how dirty your grinder is. You might get it clean in one go, it might take two or three tries to salvage everything.
When you're done, find a shallow dish to dump the iso in and let evaporate. This'll take a while, but once done all your dried up leftovers should remain, ready to be scraped up.
When I did it the end result was more of a golden stain on a plate, though, so get a little more info before attempting everything the way I did. I'm pretty sure I just overestimated the amount of kief in my grinders and used much too large of "cooking utensils" to end up with my disappointing final product. I'll have to try again one of these days... but honestly, I always had great results using a handheld kief-press and a heatlamp to make lowgrade hash pucks. Those are fuckiing wonderful, just a pain in the ass to make. Slow process all-around, from gathering enough kief to make several quarter-sized pucks to actually making the pucks. Low heat and a constant re-tightening of the press over several hours. I just got tired of doing it, tbh.