Since I will be using a sander rather infrequently, I figured I'd save myself collecting more hardware by buying just a (portable) belt sander and using it for both serious sanding (areas on floors that are unreachable with a machine) and light-weight sanding (wood tabletops).
But for tables, I'm having a hard time getting a smooth finish, using 180-grit paper. Maybe 220-grit will make a big difference, but I doubt it.
Does either an orbit sander or a mouse sander give you more control when sanding a wood tabletop, to get a smoother finish? (I've applied linseed oil to seal, and am now applying polyurethane to finish).
Asked differently, is a belt sander just too much (unmanageable, takes too much too quickly, not random but leaves linear streaks, ..) to be used for finishing tabletops?
Best Answer
Your biggest problem is that handheld belt sanders are optimized for removing large amounts of material quickly. They only run at a single, fast speed and ergonomics of the thing contribute to digging in. Think how much more abuse your lawn would take being driven over by a car restrained by a chain around the rear bumper.
Floor standing machines, by contrast, can be much less aggressive. Thickness sanders are used to dimension wood for instruments. Wide belt sanders can put a finish sanding on just about anything.
That being said, unless there's an absolute ton of dust in the air I'm partial to hand sanding finishes (as opposed to the underlying wood). It doesn't really take any longer with practice, and it's less cumbersome when switching from the block to paper for curved surfaces. [Though once the table is large enough I'd switch to a machine.]
As far as the wood itself goes, I've always liked a half sheet orbital sander for large surfaces like tabletops. The extra size is a big improvement over the palm sander and you can go flush into corners with it. The quarter sheet palm sanders are probably a bit more convenient for most things though.
FYI the largest advantage of the round random orbital sander over the sheet ones historically is that the disks come with holes in them which allows you to connect it to dust collection. It still beats the hole punch guide newer sheet sanders that support dust collection subject you to. If you only work outdoors both are viable options.