I wonder why more belt sander mfr's don't offer these accessory frames. Bosch does which is why I bought their sander. Sanding frames are such a huge game changer for flattening large panels. By increasing the footprint from the 4"x8" platten to 10"x16" and adding depth of cut adjustment a 4"x24" belt sander can be controlled, even finessed, even one handedly. No grabbing, no rounding over edges and no oh shit taking of a huge divot because you blinked.
Today I flattened a 22"x43" butcher block counter top for our 1/2 bath. There was about an 1/8" of twist in the panel. I set the depth of cut fairly light to maximize control and took my time with a fresh 100 grit belt. Here the surface is cross hatched with Sharpie lines to gauge progress.
After several diagonal passes each way the high spots are somewhat knocked down and the low spots are clearly shown. Without the frame the tendency would be to remove the lines in the low spots which just makes them deeper. The frame bridges the low spots forcing you to keeping making long passes and lowering the high surrounding surface.
When the surface is flat the Sharpie lines are gone and just the diagonal scratch pattern remains. BTW belts matter. The 3M purple belts are the only kind I'll use on bare wood. The consistency of the grain size is excellent so you don't get those hard to remove extra-deep scratches from a few oversized grains. Now it's just a matter of sanding with the grain to remove the diagonal pattern before switching to a RO finishing sander.
Ready for finish sanding
Today I flattened a 22"x43" butcher block counter top for our 1/2 bath. There was about an 1/8" of twist in the panel. I set the depth of cut fairly light to maximize control and took my time with a fresh 100 grit belt. Here the surface is cross hatched with Sharpie lines to gauge progress.
After several diagonal passes each way the high spots are somewhat knocked down and the low spots are clearly shown. Without the frame the tendency would be to remove the lines in the low spots which just makes them deeper. The frame bridges the low spots forcing you to keeping making long passes and lowering the high surrounding surface.
When the surface is flat the Sharpie lines are gone and just the diagonal scratch pattern remains. BTW belts matter. The 3M purple belts are the only kind I'll use on bare wood. The consistency of the grain size is excellent so you don't get those hard to remove extra-deep scratches from a few oversized grains. Now it's just a matter of sanding with the grain to remove the diagonal pattern before switching to a RO finishing sander.
Ready for finish sanding
