Here's an example. This is a home-spun, handknit cardigan I did about a year ago. It has about 50% merino in it - the blue colour, especially, has high fine-wool percentage (75% merino/polwarth). The higher percentage, the bigger the tendency to pill.
[handspun, hand-knit cardi (my own design)]
After only a year of wear, the underarm areas (on sleeves and body) as well as the bottom blue band, are really starting to pill fairly badly:
[pilling under the arms...]
[...and along the bottom]
After reading up on pill removal, I did some experiments using:
1. a hair clipper (the kind I use for my husband's hair),
2. a battery-operated device that supposedly sucks in the pills and cuts them off,
3. a cheap comblike tool with a very rough metal surface, called a "d-fuzz-it" and I think made by Dritz, costs like $3, and finally,
4. a piece of pumice ("sweater stone")
[piece of pumice stone - don't ask me how they made it blue]
The only one that worked well was item 3.
The hair clipper / beard trimmer is scary to use, you have to watch like a hawk that those blades don't get too close to the knitting. Then, the fluff that it does chop off just stays on the sweater (and sticks) so it doesn't save any work from just picking off the pills by hand.
The batter-operated vacuum thingy is worthless on bigger pills. It doesn't have the strength to remove anything. Don't waste your money.
The comblike tool has a rough surface that collects the pills. It requires a firm hand, you scrape across the sweater and it collects fluff. It works extremely well. It takes a lot of stuff off, and yes, this wears out the sweater. "Pilling" is "wear". In other words, fine wools don't wear well. Which, I remind you, is why I'm not a big fan...
The piece of pumice (a type of volcanic stone that's also used to remove callouses from your feet, I got it from the manicure section of my local drug store for a few dollars). You rub it across the sweater. More expensive are "sweater stones", which are exactly the same thing in block form. I found this thing very effective as well, but it was much more awkward to hold and maneuver across the sweater. It also felt much more aggressive than the comb and seemed to remove more fuzz.
But, after once-over with the defuzzer, my sweater is looking much better.
[...after a go-over with the sweater "comb"]
[...no more pills!]
[Here's the pile of fluff I took off the sweater]
I'm now going over all my "soft" sweaters with this little thing. It's going to live in my top drawer!