A well made new wheel like Caswell sells does not need to be raked unless you want to be covered in a mess of cotton fibers IMHO. You should be able to evenly load a new wheel with greaseless if you are experienced. If not then Glu-Tite is your friend will help load a wheel but don't hog it on just a thin layer that you can see through is enough. Once the greaseless had adhered to the wheel it should be in an even coat. I tried to take a couple of pictures as a reference. The first in an even coated wheel that I've used and loaded a few times. The second kind of looks like a broken lava field and it's time to rake this wheel and apply fresh greaseless. Stay towards the bottom of the wheel and hang onto it tight as you introduce it to the periphery of the wheel. It may try and rip it from your hands. Respirator and eye protection are mandatory in my book.
Once I think my wheels are not cutting well I reload them. I don't wait until all the compound is worn off the wheel. You'll be able to see when it is not cutting efficiently. It will look more like it is polishing the metal than cutting. Kind of like sandpaper. The fresh new stuff cuts the best. The grit on the wheels wears like sand paper. Someone once said use sandpaper like someone else is paying for it.
Do take the time to mark your wheels with rotation direction and grit size. I know some think the direction makes no difference but the greaseless lays down in one direction and if you reverse it the first time you touch steel to the wheel you'll have compound breaking off the wheel and flying everywhere. It will also cut more even with no deep cuts.
I could drone on but I'll leave it here.
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