Wayne, today I do as you and use the Disc Doctor (or Music Direct) fiber pad brushes with much better results than the built-in VPI 17 brush. When I have used the VPI 17 brush, I pumped out enough fluid to full wet the surface ahead of the brush and then lightly tap out a bit more during the first revolution so the brush is always pushing a little wave of fluid in front of it. Over 15 years of use, I never had a problem with the brush causing any damage to an LP (over a few thousand LPs), but I never let it rotate dry on an LP, either.
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