here is who I like
A & H abrasives
18008316066

they make all my belts and inflatable sanding drum sleeves and every oddball
thing I need. prices are good on zirconia stuff. if you order before noon they
ship it the same day.
like I wanted PSA discs for my makita sharpener. they made them with a 1/2"
hole for me. a sheet of zirconia 24"x36" for my lapping plate.
sleeves for my sanding drums in any grit and any weight backing. they can do
single items though you get a discount on orders of three or more.
all their material is priced per square foot so shape does not matter.
always use the blue zirconia on grits 120 and below. it last so much longer it
is the best value.
I get 6x89 belts for about 15.00 that's blue zirconia belts. that's 1/2 for
local of the same brand.

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Knight-Toolworks & Custom Planes
Custom made wooden planes at reasonable prices
See http://www.knight-toolworks.com For prices and ordering instructions.