Sanding curved surface

[Alex Berkovsky]

I need to sand a curved apron on both sides. Is there anything that I can buy to sand a curved surface? I have seen some sanding sponges at the BORG - will that do?

[Ken Shoemaker]

Rip thin strips of wood ( 1/8") and glue sandpaper to it. On the other side you can glue a couple of blocks to hold onto. It will bend to match your curved surface.

I think I understand the question.... Ken

[Jamie Buxton]

Almost any sander will handle the outside curve -- the convex one. I sand those faces with a random-orbit sander. Just keep moving to avoid flat-spotting the curve.

The inside curve -- the concave one -- is a little more difficult. You can always do it by hand, but that can be lots of work. If you have a power sander which doesn't rotate, you can generally get it to do the job. Power sanders which don't rotate include belt sanders and orbital sanders. (Orbital... y'know, like those 1/4-sheet finishing sanders. Mine's a Porter Cable 330.) You can make a curved platen which fits between the sandpaper and the usual backing plate. The curved platen can be made from something hard (wood, or bondo) if you want a distinct curve, or something softer (foam plastic or rubber) if you want something more compliant. If you go the foam rubber route, you don't need to be very exact about the curve; the foam and the sandpaper conform to the wood which you're sanding.

[Doug Shepard]

If you've got access to a spindle sander, and if the apron isn't installed in the table yet you can do it fairly easily with the sander. You just need to clamp a single point fence (a scrap block with a rounded point) to the spindle sander table. Clamp so the point of the block is the thickness of your apron away from the spindle sleeve. Works pretty good. An alternative is to rig up a similar fence on a drill press table and use DP type sanding drums.

[Doug Shepard]

Alex - It just dawned on me this morning that I had "thicknessing a curved surface" on my brain last night when I posted. Just for sanding the surfaces you don't need the single pt fence at all, although either the osc. spindle sander or DP mounted sanding drum is still a good method for sanding the curves. The DP mounted type is definitely the cheapest of the two options. Get the largest diam. one you can find and keep the apron moving past the drum and you shouldn't end up with any flat spots.

[Alex Berkovsky]

...either the osc. spindle sander or DP mounted sanding drum is still a good method for sanding the curves...Doug,
I recently bought the Ridgid edge belt/spindle sander (http://www.homedepot.com/cmc_upload/HDUS/EN_US/asset/images/eplus/165531_4.jpg)... I didn't realize that it can be used to sand my apron - DOH! Can I also sand the outside of the curved apron with the spindle?

[Doug Shepard]

Works like a charm. I sanded the apron, stretchers, and all the other curved pcs on this table with an osc. spindle sander
http://www.sawmillcreek.org/showthread.php?t=15693

The trick is to keep it moving or you can sand a curved divot into things. The biggest diameter drum/sleeve that will fit into your curve can help reduce any tendency for that to happen though. If your apron is taller than your spindle travel, just flip it around and make another pass from the other side.

[Dave Bales]

Rip thin strips of wood ( 1/8") and glue sandpaper to it. On the other side you can glue a couple of blocks to hold onto. It will bend to match your curved surface.

I think I understand the question.... Ken

Seven years later, I just benefited from this post. The drum sander wasn't getting all the little nubs off of my bandsawn template, but this trick did. Thanks, Ken!