Australianwoodsmith57_Scrapers.pdf

tools of the trade

Fine-cutting

Mill File

Hand

Medium-grit

Honing Stone

scraper

Round

Burnisher

{ Simple

Tools. A few

simple tools make a

quick job of creating

a sharp burr on the

edge of your scraper.

Success with a hand scraper is

as easy as one, two, three.

Flare the Edge. Long strokes with

the burnisher held square to the

face will flare the edge.

Roll the Burr. Now, tilt the

burnisher very slightly to begin to

roll the flared edge .

Sharp Hook. Finally, a couple of

light strokes at a steeper angle will

create a sharp hook.

For such a simple tool, a hand

scraper (also called a cabinet or

cardscraper)canbeincrediblyuse-

ful.Andinthatspirit,I’vealways

takentheapproachthatputtinga

hand scraper to work should be

justassimpleasthetoolitself.The

technique I use takes a few min-

utespreparationandyou’reready

togo.

Why a Scraper? Ascraperisnothing

morethanathin,rectangularpiece

offlexiblesteel.Itworkskindoflike

acrossbetweenahandplaneand

sandpaper.Ascraperwillliftfine

shavings(andalittledust)fromthe

woodsurfacewithouttheworryof

tearout.So,it’seasiertousethan

ahandplane,butitdoesthejoba

lot faster than sandpaper. I often

reachforascrapertoremoveplaner

orsawmarksondifficultwood,to

smoothpanels,or“flushout”ply-

woodedging,asshownabove.

The Burr . Whenyourunyourfinger

acrosstheedgeofawell-sharpened

handscraper,you’llfeelan“invis-

ible” hook or burr (drawings on

oppositepage).Thisiswhatmakes

ascraperwork.Whendrawnacross

asurface,theburrdigsin,andthen

peelsbackafineshaving.So,when

you“sharpen”ahandscraper,your

goalistoformacrispburronthe

edge.

Three Quick STepS. Thephotosbelow

alongwiththephotoanddrawings

on the opposite page, show the

toolsandstepsIusetocreatethe

burr.Asyoucansee,alltheworkis

donewiththescraperclampedina

benchvise.Amillfile,amedium-

gritstone,andaburnisherarethe

onlytoolsneeded.

File. First,youneedtoremovethe

old, dull burr and make sure the

edgeofthescraperisstraightand

square.Allthistakesisseveralquick

passesovertheedgewithamillfile.

Time?Maybe30seconds.

hone . Next,Ipickupthestoneto

quickly hone the edge. This step

simplyremovesyourfilingmarks

andensuresthattheburrformed

nextwillbecrispandsharp.

The Burr. Now, you can use the

burnisher (just a hardened steel

rod)todrawtheburrontheedge.

First,lubricatetheedgewithadrop

ofoil.Thenahalfdozenbackand

forthstrokes,withincreasingpres-

sure,flarestheedge.Next,bytilting

theburnisher,theflarededgesare

“rolled”overandthesharphook

isformed.

Asimpletouchofthefingertells

me when the scraper is ready.

Honestly,fromstarttofinish,Inever

spendmorethanafewminutescre-

atingtheburr.Finally,theboxonthe

opposite page will help you put

yourscrapertowork. W

How To: Handle a Scraper

BURR LIFTS

AND PEELS

SHAVINGS

SKEW

SCRAPER

TO GRAIN

DIRECTION

PULL GRIP

There’sreallynosinglewaytouse

ascraper.But,afewpointerswill

helpyougetbetterresults.

a SlighT BoW .Usingascraperisa

two-handedjob.Themainreason

forthisisthattheflexiblescraper

works best when forced into a

slightbow(lowerrightdrawing).

Thisbowedshapeconcentratesthe

scrapingactionoverasmallerarea

and reduces the effort involved.

It also keeps the corners of the

scraperfromgougingthewood.

puSh or pull . Somewoodworkers

like to “crown” the blade away

from their bodies and push it

across the wood (middle draw-

ing).Others,myselfincluded,find

it easier to pull the scraper (top

drawing). This method makes

bending the scraper a bit more

work,butforme,it’seasiertosee

andcontrolthecut.

TWo angleS. When you draw a

scraperacrossaworkpiece,there

areacoupleanglestothinkabout.

The first is the pitch or cutting

angle of the blade (detail ‘a’ at

right).Thesecondistheangleof

thelong scraper edge inrelation

to the grain direction. The good

newshereisthatneitherangleis

critical.

The cutting angle is usually

somewherebetween45°to60°to

vertical.Butbasically,it’swhatev-

erangleseemstoworkbest.The

burryouformisn’talwaysgoing

tobethesamesizeandshape.So

basically,it’sjustamatteroffeel.

Fine shavings let you know it’s

right.

As the drawing shows, the

scraper blade is held slightly

skewedtothegraindirection.This

way,thescraperismorelikelyto

hit the high spots and skip over

the low spots. To avoid creating

ridges, I alternate angling the

bladefromonesidetotheother.

You’ll find that the learning

curve for success with a scraper

isaprettysmallhilltoclimb.And

it’sdefinitelyworththeeffort.

PUSH GRIP

Start Fresh. The first step in

sharpening a scraper is to take

several passes across the edge

with a file to remove the old burr

and square the edge.

FLEXING SCRAPER

CONCENTRATES

SCRAPING

ACTION

T A Quick Hone. A medium-grit

stone will smooth any roughness

on the edge left by the file.

WORKPIECE

AustralianWoodsmith

No.57

AustralianWoodsmith

mastering the

AustralianWoodsmith

No.57

AustralianWoodsmith

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