Lance Hedrick is the guy I was talking about, I screwed his name up, sorry. He is a very knowledgeable with things about coffee; not saying he's the guru of coffee, but you should watch his videos, he's very analytical, not a one of those "let me show how to make coffee and taste it" which he does later after the detailed scientific stuff is over, he goes into deep detail, sometimes too much for my liking.
I have the Timemore Chestnut C3 ESP Pro, Hedrick used the KINGrinder K6 I think it was, and I've seen other videos of users using lower end grinders and not one ever reported their grounds caking, there is always minor small clumps though; the only thing I can think of why yours is caking is because of condensation and moisture from steam, maybe you're too close to the kettle when it's boiling water, or maybe high humidity inside the home, and that moisture gets inside the grinding chamber; it could also be static electricity, if the house to too dry static electricity becomes a problem, if it is static electricity all you need to do is a coffee spritzer and put deionized water in the spritzer and very lightly mist the beans before grinding. There are coffee experts on You Tube that always spritz their beans before grinding, I don't have COD, I seriously doubt spritzing the beans makes the coffee taste better as they claim.
If none of those suggestion cures the clumping, the way you take care of the clumping is to buy a cheap WDT Espresso Distribution Tool Espresso Stirrer Tool, these cost about $20 on Amazon, and if you copy from WDT all the way to the comma and paste it on Amazon a $20 one should appear, that is a good well-made tool, it breaks up the clumps, I use one, but I don't spritz but the spritzer thing is also cheap but I just don't see any advantage of doing all of that.
We have to keep in mind that making coffee at home has become a hobby, and as such all kinds of tools are on the market promising one thing or another, all sorts of coffee makers are on the market as well, and the prices of this stuff have gone up because it's profit making time from the hobbyist so we're not only being scammed but taken for a ride. Just 3 years ago I could have bought a Gaggia E24 for $399, that same machine now costs $540, that's not from inflation, that is pure profit, inflation only counts for $41 dollars of that! The prices went up because the demand went up, and the coffee industry knows we'll spend the money. Even manual lever espresso machines went up, the Cafelat Robot went from $440 to $600, (again, only $42 counts for inflation) sure it's the best one on the market for this type but the price hikes are all about taking advantage of the hobbyists. I watched this go for the last 20 years in the cycling industry, charging people who don't know $12,000 and more for a bicycle that cost the company $1,000 to make!!! These companies, be it coffee or cycling, etc., time the market, when the buying surge cools down, something new comes out to pump up sales again. Even the stupid AeroPress which use to cost $20 is now $40 for the cheapest one, (only $2 counts for inflation); but they came out with a stainless-steel job that is $170; all those things are is French Presses, they are immersion makers, I can buy a high-quality Muellerliving double walled stainless French Press for $45, how is it that AeroPress thinks theirs is worth $170? IT'S NOT! It doesn't cost any more to make the stainless French press as it does to make the AeroPress!
It's all about going after the hobbyist money.
There are some companies still holding their prices in check, such as the Technovorm Moccamaster and Flair, for how long they'll hold their prices is anyone's guess.
