The smaller gauges, in particular, are super easy to "ruin" just by accidentally touching to something that is not sparkly clean. The part will stick and not release, or the vacuum can clog up quite easy. Alcohol gets them back to peak performance right quick. I've tried using a brush dipped in alcohol to poke a strand in there. It's much easier to just shoot alcohol out the needle with a syringe. Then pump some air through it to dry it out.