Combine power- and hand-sanding

for good results with no wasted time

B Y D A V I D S O R G

w

SandingBasics

he course of true love never did runsmooth, according to Shakespeare,and smoothing wood true rarely

causes love to course, it would seem. Bore-dom and fear are more common feelingsamong woodworkers when sanding theirprojects. But proper sanding is a crucialpart of woodworking, so please read onfor some tips and techniques that will turnyour boredom into serenity, and your fearinto fun.

I’ll stick my neck out and state that noproject should be finished without first be-ing sanded. Even if you are a hero with thehandplane or skilled with the scraper, youwon’t be able to get a surface that is uni-formly smooth and with an even sheen. In-evitably, there will be tiny depth changesfrom adjoining passes of the blade, whilethe sole of the plane can burnish strips ofwood that may show up after a stain or aclear finish has been applied.

Those who rely solely on power tools willinevitably be left with planer- and jointer-knife marks and fibers crushed by the feedrollers. Router tables can leave gouges andscratches, and assembly often produces

T

some errant glue splotches. All of theseblemishes should be removed before a fin-ish is applied, and sanding is the best wayto achieve this. The most efficient way tosand a surface is with a combination ofpower-sanding and hand-sanding

Power-sanding comes firstOf course, you could do all of your sandingby hand, but why? Even if you use powersanders wherever practical, there will beenough hand-sanding on almost any pro-ject to give you plenty of hand-done satis-faction. Power sanders deliver results withmuch greater speed, and with minimalpractice they’ll also deliver a flatter surfacethan sanding by hand alone.

The good news is that unlike much ofyour other shop equipment, quality sand-ing tools will not cost you much. I stronglysuggest you get a random-orbit sander. Apad sander also is useful, and I’ll explainwhy a detail sander is optional. Don’t forgeta dust mask and hearing protection.

Fast stock removal with a random-orbit sander—Random-orbit sanders arewonderful machines. The pad has dualmotion: It spins in a circle as well as in aneccentric orbit. These sanders are great forrapidly smoothing and leveling raw wood.Five-in.-dia., palm-held models are mostcommon, but you also can buy 6-in.-dia.,two-handed versions.

Most random-orbit sanders have holesin the pad (and, of course, in the sandpa-per) for dust extraction. The sanding disksare backed with either pressure-sensitiveadhesive (PSA), which is cheaper, orreusable hook-and-loop systems.

Older sanders need to be switched onwhen already resting on the surface of thewood, or they will spin too fast and gougethe wood when you try to bring them in

PA D S A N D E R S

Less aggressive than random-orbitsanders, pad sanders are easier tocontrol, which makes themsuitable for narrower and moreconfined areas such as table legsand the insides of cabinets.

T O O L S F O R S A N D I N G

R A N D O M - O R B I T S A N D E R S

These machines are great for removinglarge amounts of wood from largesurfaces. They are less suitable for smallareas, and their shape prevents themfrom reaching into inside corners.

N O V E M B E R / D E C E M B E R 2 0 0 4

H A N D - S A N D I N G T O O L S

Sand by hand to finish the job. For flat areas,use a backing block made from cork or rubberto prevent your fingers from applyinguneven pressure. To keep moldings crisp,use commercial rubber profiles or shop-made foam ones to back the sandpaper.

Achieving a well-sanded surface in themost efficient way requires a combinationof power-sanding and hand-sanding.

N O V E M B E R / D E C E M B E R 2 0 0 4 41Photos, except where noted: Mark Schofield

for a landing. Most new models have elec-tronic speed control, which allows you tolift the sander to apply it to an adjacent sur-face without having to turn it off and restartit each time.

Random-orbit sanders will do a speedyjob on large surfaces and bring two piecesof wood into the same plane. However, atthe edges of a workpiece, keep the major-ity of the pad on the wood, or you’ll riskdishing or rounding over the edge. By thesame token, keep these sanders moving;don’t concentrate on one spot, or youcould create a little bowl.

Orient your project, if you can, so thatyou’re working horizontally. By letting theweight of the sander work for you, you’ll

or table legs, as well as on the insides ofcabinets and in other confined spaces.

The right grit from start to finish—With either type of sander, I’d rather startwith 150-grit than 120-grit paper on mostpieces, even though it may take longer toremove some milling marks. For wood thatis already in good shape, especially withthin-veneered sheet goods, I start with 180-grit paper.

Note: The grits I refer to here are basedon the FEPA scale, which uses the prefix P,rather than the alternate CAMI, or C, scale.In the 150 to 220 range, the grits are nearlyequivalent, but it’s best to work with thepaper from one scale.

Don’t continue using a piece of sandpa-per until the sand is all gone and there isn’tanything left but the paper. That’s a falseeconomy if you’re charging for your time;and if you’re woodworking for fun, well,you’re taking away a bunch of it. Move to afresh section of sandpaper as soon as youfeel it stop cutting or start to clog, or whenit requires you to exert more pressure.

Having experienced this the hard way, letme assure you that it’s very important tovacuum and/or blow off the entire piecebetween grits. I do both, then wipe it witha tack cloth. One piece of 150 grit being

gain more control with less fatigue. Also,sand subassemblies before glue-up. It’smuch easier to sand a frame-and-panel, theaprons of a table, or a drawer’s parts beforethey’re assembled.

Pad sanders give more control insmall areas—Pad sanders, also calledpalm sanders or finish sanders, use a sim-ple orbital pattern, and the pad does notrotate, giving a much slower sanding ac-tion but greater control. The square pad al-lows the tool to get fairly close to insidecorners (but beware getting it too close,where it quickly can chew up the adjacentsurface). This type of sander works well onsmaller surfaces like the edges of shelves

42 F I N E W O O D W O R K I N G

W I D E PA R T SAgain, a random-orbit sander does wellhere. Note: It is easier to sand partssuch as table aprons before assembly.

N A R R O W PA R T S

On smaller pieces such asthe parts for a frame, apad sander gives morecontrol than a random-orbit sander.

Photo, this page (top left): Matthew Gardner

L A R G E PA N E L SWith their wide contactsurfaces, random-orbitsanders are naturally athome on large panels.

Sanding with power

P O W E R - S A N D I N G F L AT S U R FA C E S

N O V E M B E R / D E C E M B E R 2 0 0 4 43

swirled around on your 220-grit pad willmake you curse when you see the results.

Tips for efficient sanding—With a cabi-net, begin sanding on the inside: If you startwith the inside while you’re fresh, you’lltake a few extra minutes to do it right in-stead of skimping on it at the end.

For veneered plywood, you can start andstop with 180-grit paper if the inside will be minimally seen or used. Use a hand-sanding block on the corners and on anymore visible areas such solid-wood edging.

Devote more time to visible areas andthose likely to be touched. Ending with180-grit paper is fine for softwoods, but goto 220 grit for hardwoods. On end grain, goone grade finer so that it doesn’t absorb thestain or clear finish as deeply.

How do you know when you’re finishedpower-sanding? Wipe some mineral spiritson the surface and sight across the woodtoward a strong light. Pay no attention tothe beautiful color that appears; instead,look at the surface for telltale scratches, es-pecially the ugly orbital kind. You wouldlike to see a uniform appearance with norough areas or single outstanding scratches.Sometimes it’s easiest to see this right at themoment of evaporation, when the ruts of

S A N D I N G D E TA I L S

A quicker way to sand moldings.Detail sanders come with an assort-ment of different pads designed to fitmost molding profiles. The radius onthis pad matches the bead of theapron (left). One disadvantage of detailsanders is that the adhesive-backedsandpaper frequently comes awayfrom the pad (above).

C H E C K YO U RP R O G R E S S

With the workpiece

lit by a strong light,

wipe the wood

with some mineral

spirits and check

the surface for

obvious scratches

and rough areas.

the scratches will still be shiny with fluidwhile the top surface is dull with dryness.If you take this step, you’ll avoid the agonythat many experience when they apply astain only to see the scratches jump out.

Sanding details and moldingAfter sanding the wide-open areas, howshould you sand profiled areas? Manufac-turers advertise detail sanders as the an-swer to sanding any shape and anyconfined space. These sanders come witha variety of pads designed to fit differentprofiles. Although I own a couple of detailsanders, I could live without them, mostlybecause it’s too much trouble to constantlychange the paper on them; by their nature,they put their sanding action into a smallarea of sandpaper that wears very quickly.

Most of the time I think it’s quicker to domoldings, interior corners, and other smallareas by hand. To keep the moldings crisp,use commercial rubber profiles that covermost convex and concave shapes, or youcan make your own profile blocks frompieces of foam-insulation panel.

The end grain on raised panels requires aspecial sanding sequence to tone it into therest of the panel. Start by sanding acrossthe grain with 150- or 180-grit paper to dealwith the rough texture. Then sand the en-

S A N D I N G A F T E R G L U E - U P

No matter how thoroughly you

sand parts prior to assembly,

there still will be small areas

to touch up by hand-sanding

with 220- or 320-grit paper.

Areas where glue was removed

with a damp cloth may need

smoothing (top), or there may

be two pieces that don’t join in

a perfect plane (bottom). To

avoid cross-sanding where

grain intersects, mask off one

of the pieces.

44 F I N E W O O D W O R K I N G

E N D G R A I N

To lessen end grain’s darkerappearance when the workpiece isfinished, burnish the wood and fill thepores by sanding end grain up to 320-grit paper.

F L AT A R E A STo maintain a flat surface, youshould always use a backing blockwhen sanding large areas.

H A N D - S A N D I N G F L AT S U R FA C E S

E D G E SBreak the edges on a project not only to reducefuture damage but also to prevent finish fromforming a mound at the edges.

Sanding by hand

Photo, this page (top left): Matthew Gardner

tire profile on all four sides of the panelwith 180- or 220-grit paper. Last, sand justthe end grain with 320-grit paper, goingwith the grain in short strokes to eliminateany cross-grain scratches and to lessen theend grain’s ability to absorb finish.

Final hand-sanding gives a finishing touchNo matter how much you are able to usemachines for the initial stages of sanding,you’ll want to give each surface some finalsanding by hand. Primarily, this is to get ridof the small orbital scratches left by the ma-chines, replacing them with smaller, finerscratches that are all parallel to the grain ofthe wood and hence less noticeable.

You should back up the sandpaper witha sanding block wherever possible tomaintain a flat surface. I find the palm-sizedrubber blocks most convenient because

they also can be used for wet-sanding be-tween coats of finish. Other choices in-clude cork blocks or wood blocks facedwith a sheet of cork.

If you plan to use a water-based stain orclear finish, there are a couple of extra steps.After the final hand-sanding, wipe down thepiece with a damp sponge. After the wooddries, very lightly sand with the same-gradepaper you finished with, but be careful toremove only the raised grain. Watch out forsandpaper coated with stearates: Althoughthey do a better job at preventing clogging,

allowing the sandpaper to last longer andsand more smoothly, stearates are waxyand interfere with many water-based fin-ishes, causing fisheyes on the surface. Ifyou’re planning to use a water-based fin-ish, check with the manufacturer to seewhether the finish is compatible withstearated sandpaper. Last, as I recommendfor all finishing methods, test each sandingstep on a sample board. �

David Sorg is a finisher and artist who lives inDenver, Colo.

N O V E M B E R / D E C E M B E R 2 0 0 4 45

Rubber profiles. Using a rubber pad that fitsthe molding helps keep the edges of the pro-file sharp.

Sanding curves by hand. Contour the paperto fit curves in the wood.

H A N D - S A N D I N G D E TA I L S

C U R V E C O N S C I O U S

Insulation foam shaped to match the panel’s pro-

file makes a good backing for sandpaper (above).

The end grain may need to be sanded with paper

that is one grade coarser than that used on the

rest of the panel, in this case, 150 grit (left).

Then sand the entire panel with 220 grit before

removing any cross-grain scratches on the end-

grain sides using 320-grit paper with the grain.