Finishing Techniques: Hand-sanding rounded edges
Finishing, Surface Preparation, and Sanding
When it comes to the fine finishing of wood, there is but one universal rule: a properly prepared wood-grain surface is critical. Contractors may be able to slather their decks and staircases with sealer with barely a glance at planing and sanding, but furniture-makers would be wise to take the time to not only learn how to prepare their pieces for finishing, but also be sure to follow-through with the myriad steps to a proper surface.
Unfortunately, surface preparation is a series of steps that many furniture-makers skip - in whole or in part - due to lack of knowledge or patience, or both. For a detailed look into surface preparation and finishing, I recommend Finishing and Finishing Techniques from the Taunton Press (link to Google Book here). In this article, I am focusing on one tiny portion of the surface prep sequence - hand-sanding - and specifically how to hand-sand a rounded edge without machining a sanding block with an internal radius to match your curve's radius.
I first came across this popular technique while preparing a beautiful walnut and curly-maple glued panel, which was to become a set of floating wine racks for a customer on Cape Cod.
Preparing to Sand (or glue-join)
After power-jointing the walnut board and maple edges, I ran my #5 jack plane along the edges to remove the waves created by the jointer's drum-mounted blades. This ensures a super-flat edge-grain-to-edge-grain gluing surface. Once the maple edging was set, I jointed and planed the whole piece to get an almost smooth, flat surface and a perfectly rectangular profile.
Again, I hit the edges with the jack plane to remove the waves from the jointer. Then I rounded the edges on the router table to give the wine racks a soft, smooth look and feel. I still had waves from the jointing process on the faces of my board, but instead of hand-planing the faces (an unduly risky course of action with such a nearly-perfect surface underhand) - I went straight to the sandpaper.
Hand-Sanding with a Sanding Block
Rather than use power sanders on jointed surfaces, I go straight to the hand-sanding. For some reason, power sanders seem both leave deep scratches and take a long time to do the trick. Hand sanding with a good sanding block is fast, easy to control, and leaves a very nice surface for the next higher grit of paper.
A good sanding block is key: it should be square and sturdy, with rounded edges to both reduce deep scratches and lengthen the life of the paper. Take a look at these pictures of one of my sanding blocks: it's made from a piece of a table leg that was itself made of three pieces of scrap mahogany, then used to test my Festool Domino joiner before I glued a piece of cork to one face to make a truly wicked sanding block:
With my block, I quickly ramped up from 120-grit to 220-grit sandpaper, wiping away excess dust and grit between sandings. One thing i do like about hand sanding at this point is that there's no vacuum to take away the dust as you work. This allows dust to pack the pores of the surface as you sand. On woods like walnut, on which I happened to be working at the time, the large pores will soak up finish and frustrate attempts at a glass-smooth final surface - unless they're sealed. Commercial pore sealers are tinted with pigment, so many woodworkers make their own out of the sawdust of the appropriate wood. Hand-sanding packs the pores with the very dust from the wood being worked, without the extra step of pore-sealing. Skipping the sealing step won't deliver as smooth a finish, but hand-sanding is a good, pore-packing compromise.
Hand-Sanding a Curved Edge
And now, finally, to the subject of this article: hand-sanding a curved edge without machining a specialized, grooved sanding block with the appropriate internal radius:
Naturally, I don't want to spend time making jigs and tools when I don't have to. Don't get me wrong: a good jig is as interesting a project as a chest of drawers in my eyes. But when I'm experimenting, as I was on the day I made these wine racks, I don't want to take the time to measure and machine a sanding block just to smooth the rounded edges of a few pieces.
Instead, I use the block like a fence, holding it flush to one side of the curved corner, and pulling the sandpaper taut over the rounded edge. From this starting point, I can sand with the grain for smoothing, or against the grain with a wet/dry paper to raise the grain before smoothing it off. Unlike a block with a machined radius to match my edge's radius, I have to hit each edge twice - once from each side - but if I'm only doing one or a few pieces with such an edge, it's an overall time-saver.
Check out this video of the technique. And remember, packing the pores with dust is great, but be sure to clean your abrasive often to refresh its bite on the grain:
Like what you see here? Follow me on Twitter, or check out other articles I've authored on HubPages.
When it comes to the fine finishing of wood, there is but one universal rule: a properly prepared wood-grain surface is critical. Contractors may be able to slather their decks and staircases with sealer with barely a glance at planing and sanding, but furniture-makers would be wise to take the time to not only learn how to prepare their pieces for finishing, but also be sure to follow-through with the myriad steps to a proper surface.
Unfortunately, surface preparation is a series of steps that many furniture-makers skip - in whole or in part - due to lack of knowledge or patience, or both. For a detailed look into surface preparation and finishing, I recommend Finishing and Finishing Techniques from the Taunton Press (link to Google Book here). In this article, I am focusing on one tiny portion of the surface prep sequence - hand-sanding - and specifically how to hand-sand a rounded edge without machining a sanding block with an internal radius to match your curve's radius.
I first came across this popular technique while preparing a beautiful walnut and curly-maple glued panel, which was to become a set of floating wine racks for a customer on Cape Cod.
Preparing to Sand (or glue-join)
After power-jointing the walnut board and maple edges, I ran my #5 jack plane along the edges to remove the waves created by the jointer's drum-mounted blades. This ensures a super-flat edge-grain-to-edge-grain gluing surface. Once the maple edging was set, I jointed and planed the whole piece to get an almost smooth, flat surface and a perfectly rectangular profile.
Again, I hit the edges with the jack plane to remove the waves from the jointer. Then I rounded the edges on the router table to give the wine racks a soft, smooth look and feel. I still had waves from the jointing process on the faces of my board, but instead of hand-planing the faces (an unduly risky course of action with such a nearly-perfect surface underhand) - I went straight to the sandpaper.
Hand-Sanding with a Sanding Block
Rather than use power sanders on jointed surfaces, I go straight to the hand-sanding. For some reason, power sanders seem both leave deep scratches and take a long time to do the trick. Hand sanding with a good sanding block is fast, easy to control, and leaves a very nice surface for the next higher grit of paper.
A good sanding block is key: it should be square and sturdy, with rounded edges to both reduce deep scratches and lengthen the life of the paper. Take a look at these pictures of one of my sanding blocks: it's made from a piece of a table leg that was itself made of three pieces of scrap mahogany, then used to test my Festool Domino joiner before I glued a piece of cork to one face to make a truly wicked sanding block:
With my block, I quickly ramped up from 120-grit to 220-grit sandpaper, wiping away excess dust and grit between sandings. One thing i do like about hand sanding at this point is that there's no vacuum to take away the dust as you work. This allows dust to pack the pores of the surface as you sand. On woods like walnut, on which I happened to be working at the time, the large pores will soak up finish and frustrate attempts at a glass-smooth final surface - unless they're sealed. Commercial pore sealers are tinted with pigment, so many woodworkers make their own out of the sawdust of the appropriate wood. Hand-sanding packs the pores with the very dust from the wood being worked, without the extra step of pore-sealing. Skipping the sealing step won't deliver as smooth a finish, but hand-sanding is a good, pore-packing compromise.
Hand-Sanding a Curved Edge
And now, finally, to the subject of this article: hand-sanding a curved edge without machining a specialized, grooved sanding block with the appropriate internal radius:
Naturally, I don't want to spend time making jigs and tools when I don't have to. Don't get me wrong: a good jig is as interesting a project as a chest of drawers in my eyes. But when I'm experimenting, as I was on the day I made these wine racks, I don't want to take the time to measure and machine a sanding block just to smooth the rounded edges of a few pieces.
Instead, I use the block like a fence, holding it flush to one side of the curved corner, and pulling the sandpaper taut over the rounded edge. From this starting point, I can sand with the grain for smoothing, or against the grain with a wet/dry paper to raise the grain before smoothing it off. Unlike a block with a machined radius to match my edge's radius, I have to hit each edge twice - once from each side - but if I'm only doing one or a few pieces with such an edge, it's an overall time-saver.
Check out this video of the technique. And remember, packing the pores with dust is great, but be sure to clean your abrasive often to refresh its bite on the grain:
Like what you see here? Follow me on Twitter, or check out other articles I've authored on HubPages.
