Sanding Disk Preferences

Woodworkers discuss abrasive and backing characteristics that make various brands of sanding disk useful in particular applications. March 12, 2015

Question (WOODWEB Member) :
For years I've used 3M Gold Stickit 216U sandpaper sheets for hand sanding. It's has a great long lasting grit but being an auto body product has a soft paper backing that wears out too fast. We've overcome this by spray adhering a sheet of copy paper to the back of each sheet prior to use. It only takes a few seconds and makes a huge difference. I would also like to use the 216U for our 5" random orbit sanders and do keep some around. However we primarily need cloth backed disks for these sanders and I've never been able to find the 3M 216U on a cloth backer. As such I use Klingspor or whatever generic PSA cloth backed discs I can find. Does anyone have a really great long lasting cloth backed disc they use? What are your favorites, etc.? We're talking 80 grit to 150 grit range discs here.

Forum Responses
(Architectural Woodworking Forum)
From contributor D:
We use 3M 363I (363i) paper. It has F weight paper. Same grits as you are looking for. Itís very long lasting stuff. Even our metal working department has started using it as they discovered it lasts longer than the cloth discs they were buying.

From contributor W:
Look into film disks as well. The backing is more flexible, but it retains the grit better. It also means a much more consistent grain height because the substrate is flatter. The film is stiffer on the surface so the grains don't retreat into the substrate as much as on a cloth or paper during sanding.

From contributor N:
I recently got a Mirka Ceros and switched to their "abranet" discs. I can't believe the life I get out of them! I can only imagine they're more expensive than a lot of others, but they put a lot of pride in their products, and I'm proud to support them.

From Contributor H:
I suppose I should clarify the situation. We do a lot of sanding with our 5" Dynabrades using the curved edge of the pad. That is we lean the sanding pad into deep curving profiles on our curved mouldings. If we use paper back discs the paper at the edge quickly wears away and the edge of pad ends up getting chewed up by the wood. The paper back discs with wavy edges that wrap around the sanding pad are ok up to a point but will wear away much too quickly under the constant pressure of intentional edge sanding. This is why we use cloth back discs. When flat surface sanding is being done we typically go back to a paper backed PSA sanding disc.

From contributor W:
Film will hold up with the finish of paper and life of cloth - very strong on edge work.

From contributor F:
I like the film back discs as well though I can't say if they hold up as long as cloth backed? They definitely don't disintegrate easily like the paper backs do. I sand a lot of different kinds of projects so I'm generally changing grits frequently. So for me cost is a slightly bigger factor than longevity. Though they seem to hold up as well as the Klingspor paper backed I was using before.

From Contributor H:
We also change grits a lot. I solved the problem of wasting PSA discs by keeping multiple sanding pads, each with a different grit. We spin the pads on and off when we need to change grit. Really takes no longer than peeling and re-sticking a new disc.

From Contributor E:
I really like the purple 3M paper (#735U, I think), but I'm not sure whether they make a cloth backed version. The Stikit discs are on C weight paper, and the sheets feel heavier that other sheets Iíve used. They're a ceramic aluminum oxide.