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Workshop Reference Charts

Keep the NumbersWithin Reach.

A concise reference collection for drill sizes, abrasives, wood hardness, lumber dimensions, measurements and other numbers that repeatedly come up at the bench.

Open the Reference Index Drill Size Chart
Sheets
8
Drill sizes
68
Basis
1 in = 25.4 mm

Reference Index

Eight Sheets, One Wall.

Each sheet answers a question that comes up mid-job. Find the question, jump to the sheet.

Sheet register01 – 08

Sheet01

Drill Bit Sizes

Every Bit, in Three Units.

Answers
What is 11/64″ in millimetres?
Units
in · mm
Sheet
01 of 08

Fractional bits in 1/64″ steps from 1/16″ to 1/2″, with decimal-inch and metric equivalents — plus the letter and number sizes that turn up on tapping charts and older plans.

A drill index from 1/16″ to 1/2″ by 64ths, holes drawn at true relative scale — the 1/2″ hole is eight times the width of the 1/16″.
  • Decimal inches are rounded to 4 places and millimetres to 2, converted at 1 in = 25.4 mm exactly.
  • 1 mm = 0.03937″. A metric bit is rarely an exact match for a fractional one — compare the millimetre column before substituting.
  • This sheet converts sizes; it does not choose them. For pilot and clearance holes, follow the fastener maker's chart.
Fractional sizes1/16″ to 1/2″ in 1/64″ steps. Sixteenths are shaded.
Fraction (in)Decimal (in)Metric (mm)
1/16″0.06251.59
5/64″0.07811.98
3/32″0.09382.38
7/64″0.10942.78
1/8″0.12503.18
9/64″0.14063.57
5/32″0.15633.97
11/64″0.17194.37
3/16″0.18754.76
13/64″0.20315.16
7/32″0.21885.56
15/64″0.23445.95
1/4″0.25006.35
17/64″0.26566.75
9/32″0.28137.14
19/64″0.29697.54
5/16″0.31257.94
21/64″0.32818.33
11/32″0.34388.73
23/64″0.35949.13
3/8″0.37509.53
25/64″0.39069.92
13/32″0.406310.32
27/64″0.421910.72
7/16″0.437511.11
29/64″0.453111.51
15/32″0.468811.91
31/64″0.484412.30
1/2″0.500012.70
Letter sizesA–Z, the standard letter series.
Letterinmm
A0.2345.94
B0.2386.05
C0.2426.15
D0.2466.25
E0.2506.35
F0.2576.53
G0.2616.63
H0.2666.76
I0.2726.91
J0.2777.04
K0.2817.14
L0.2907.37
M0.2957.49
N0.3027.67
O0.3168.03
P0.3238.20
Q0.3328.43
R0.3398.61
S0.3488.84
T0.3589.09
U0.3689.35
V0.3779.58
W0.3869.80
X0.39710.08
Y0.40410.26
Z0.41310.49
Number sizes#1 to #60, every fifth size. The series continues to #80.
No.inmm
#10.22805.79
#50.20555.22
#100.19354.91
#150.18004.57
#200.16104.09
#250.14953.80
#300.12853.26
#350.11002.79
#400.09802.49
#450.08202.08
#500.07001.78
#550.05201.32
#600.04001.02

Sheet02

Sandpaper Grit

Coarse to Fine, and Where to Stop.

Answers
Which grit next — and where to stop?
Units
CAMI grit
Sheet
02 of 08

Each grit removes the scratches of the one before and leaves finer ones of its own. Start only as coarse as the surface needs, and let the finish decide where you stop.

Grit progressionUS (CAMI) grit numbers. Relative scratch is a comparison between grades, not a measurement.
GradeGritRelative scratchTypical useMove on when
Very coarse40–60DeepestHeavy stock removal: levelling rough glue-ups, stripping old finish, shaping.As soon as the surface is flat or the defect is gone — these scratches take several grades to remove.
Coarse80DeepRemoving planer and mill marks, levelling joints and glue lines.When every machine mark is gone and the scratch pattern is even across the whole surface.
Medium100–120ModerateGeneral surface preparation; a usual starting point on stock that is already smooth.When the coarser scratches are gone — check under a raking light.
Fine150–180FineFinal preparation before many stains, oils and film finishes on hardwood.Often the stopping point. Going much finer can reduce how much stain some woods absorb.
Very fine220–240Very fineA last pass before some finishes; knocking down grain raised by water; light sanding of early coats.Bare wood rarely needs finer. Beyond this, grits are mostly for the finish itself.
Extra fine320–400FinestBetween finish coats: removing dust nibs and raised fibres from cured film.When the film is evenly dulled and smooth. Edges cut through quickly — go lightly there.
Where to stop depends on the finishCommon stopping points on bare wood — a guide, not a rule. Species, tool and finish all change the answer; test on an offcut.
FinishCommon final gritNote
Stain on hardwood150–180Finer can limit stain uptake; test on offcuts.
Oil and wiping finishes180–220The oil shows scratches readily; stay consistent across parts.
Film finishes on bare wood180–220Varnish, lacquer and shellac bridge fine scratches.
Water-based finishesFinal grit, then againRaise the grain with a damp cloth and knock it down at the final grit.
Between coats320–400Only once the coat has cured enough to powder, not gum.
  • Don't skip too farMoving up more than one grade at a time leaves scratches the next grit struggles to remove.
  • Check between gritsA raking light or a pencil scribble across the surface shows when the last grit's scratches are gone.
  • CAMI and P-gradesEuropean P-grades (P120, P180) track US grit numbers closely through the medium range and diverge at finer grades.

Sheet03

Janka Hardness

Resistance to a Dent, Measured.

Answers
How well does this wood resist dents?
Units
lbf
Sheet
03 of 08

Janka side hardness: the force needed to press a 0.444″ steel ball halfway into the wood. Figures come from the same species data as the Wood Species library.

Janka hardness, lbfOrdered by value for quick lookup — not by preference. Bars drawn to scale on a 0–2,000 lbf axis.
SpeciesJanka hardness (lbf)
Western Red Cedar350 lbf
Eastern White Pine380 lbf
Cypress510 lbf
Poplar540 lbf
Douglas Fir710 lbf
Genuine Mahogany800 lbf
Soft Maple950 lbf
Black Cherry950 lbf
Black Walnut1,010 lbf
Yellow Birch1,260 lbf
Red Oak1,290 lbf
American Beech1,300 lbf
White Ash1,320 lbf
White Oak1,360 lbf
Sapele1,410 lbf
Hard Maple1,450 lbf
Hickory1,820 lbf

Not charted: Teak and Iroko — no Janka figure in our species data. Values are USDA Wood Handbook averages at 12% moisture content; sapele from commonly published figures. Individual boards vary.

What it measures
Indentation resistance — how well a surface shrugs off dents from dropped tools, chair legs and heels.
Higher is not better
Harder woods resist dents but are heavier, harder on edges and often harder to work. The right number depends on the job.
What it does not say
Nothing about strength, stiffness, stability or how a wood finishes.
Hardness in context, species by species

Sheet04

Lumber Thickness

Quarters, Rough and Surfaced.

Answers
What does 8/4 finish at?
Units
in · mm
Sheet
04 of 08

Hardwood is sold by thickness in quarters of an inch, measured rough. Softwood is sold by nominal size, which is larger than the board you take home.

Board ends at true relative scale: the dashed outline is the rough thickness, the solid board a typical surfaced thickness. Below, a slot gauge cut to the same surfaced sizes.
Hardwood quarter sizesSurfaced values are typical for boards planed on two sides (S2S). They vary with the supplier, the mill and how flat the rough board was — check before you plan a part to the last 1/16″.
ThicknessRoughTypical S2Smm rough → S2S
4/41″about 13/16″25.4 → 20.6
5/41 1/4″about 1 1/16″31.8 → 27.0
6/41 1/2″about 1 5/16″38.1 → 33.3
8/42″about 1 3/4″50.8 → 44.5
Softwood nominal sizesNominal size against dry dressed (actual) size under the American Softwood Lumber Standard, PS 20.
NominalActual (in)Actual (mm)
1 × 43/4 × 3 1/219.1 × 88.9
1 × 63/4 × 5 1/219.1 × 139.7
1 × 83/4 × 7 1/419.1 × 184.2
1 × 103/4 × 9 1/419.1 × 235.0
1 × 123/4 × 11 1/419.1 × 285.8
2 × 41 1/2 × 3 1/238.1 × 88.9
2 × 61 1/2 × 5 1/238.1 × 139.7
2 × 81 1/2 × 7 1/438.1 × 184.2
2 × 101 1/2 × 9 1/438.1 × 235.0
2 × 121 1/2 × 11 1/438.1 × 285.8
4 × 43 1/2 × 3 1/288.9 × 88.9
Rough and surfaced lumber explained Work out board feet

Sheet05

Fraction Conversion

Sixteenths, Decimals, Millimetres.

Answers
What is 7/16″ as a decimal?
Units
in · mm
Sheet
05 of 08

The common rule fractions to one inch, with their decimal-inch and metric equivalents. 1 in = 25.4 mm exactly.

One inch, enlarged, graduated in sixteenths — millimetres marked at every eighth.
1/16″ to 1/2″
Fraction (in)Decimal (in)Metric (mm)
1/16″0.06251.59
1/8″0.12503.18
3/16″0.18754.76
1/4″0.25006.35
5/16″0.31257.94
3/8″0.37509.53
7/16″0.437511.11
1/2″0.500012.70
9/16″ to 1″
Fraction (in)Decimal (in)Metric (mm)
9/16″0.562514.29
5/8″0.625015.88
11/16″0.687517.46
3/4″0.750019.05
13/16″0.812520.64
7/8″0.875022.23
15/16″0.937523.81
1″1.000025.40
  • Decimals are rounded to 4 places and millimetres to 2.
  • Worth remembering: 1/4″ = 6.35 mm, 1/2″ = 12.70 mm and 3/4″ = 19.05 mm.
  • Drill sizes in 64ths are on Sheet 01.

Need an arbitrary conversion?Use the measurement converter

Sheet06

Saw Blade Tooth Count

Teeth, Gullets and the Cut.

Answers
How many teeth for this cut?
Units
10″ blades
Sheet
06 of 08

Tooth count sets how big a bite each tooth takes and how much room there is to clear the chips. The counts below are typical of 10″ table-saw blades — and blade design matters as much as the number.

10″ · 24 teethDeep gullets, big bites
10″ · 80 teethSmall bites, finer finish

Tooth grinds, seen from the front

  • Flat top (FTG)

    Square tips chisel out the cut. Ripping.

  • Alternate top bevel (ATB)

    Points alternate left and right to shear fibres. Crosscutting.

  • High ATB (Hi-ATB)

    Steeper bevels score veneer faces. Plywood.

  • Triple-chip (TCG)

    A chamfered tooth leads a flat one. Laminates.

Dashed line: the next tooth in the set.

Tooth count by operationTypical ranges for 10″ blades. Other diameters carry proportionally more or fewer teeth for the same job. Educational ranges, not product recommendations.
OperationTypical teeth, 10″Common grindWhat changesTrade-offs
Ripping solid wood24–30Flat top (FTG)Fewer teeth with deep gullets clear the long chips produced cutting along the grain.Quick feed and less strain on the saw; the edge is rougher and usually jointed or planed after.
General purpose / combination40–50ATB, or ATB with a flat raker (combination)A compromise tooth count that rips and crosscuts acceptably.One blade for most cuts, but neither as clean across the grain nor as quick along it as a dedicated blade.
Crosscutting solid wood60–80Alternate top bevel (ATB)More teeth, each taking a smaller bite, shear the fibres cleanly across the grain.Cleaner cut with less tear-out; slower, hotter and prone to burning if forced through a rip.
Plywood and veneered panels60–80 or moreHigh alternate top bevel (Hi-ATB)Steeply bevelled points score thin face veneers before they can splinter.Very clean faces; the sharp points are more delicate and dull sooner.
Laminates, melamine, plastics60–80Triple-chip grind (TCG)Alternating chamfered and flat teeth resist chipping on hard, brittle surfaces.Durable in abrasive materials; not the cleanest crosscut in solid wood.
Diameter matters
The counts here assume a 10″ blade. A smaller blade has less rim, so a blade for the same job carries fewer teeth; a larger one carries more.
Hook angle
A steep positive hook bites aggressively and suits ripping. Low or negative hooks are used on sliding miter and radial-arm saws, which would otherwise tend to climb into the work.
Kerf
Full-kerf blades are commonly about 1/8″ wide at the teeth, thin-kerf about 3/32″. Thin kerf removes less wood and eases the load on smaller saws, but can flex more.
Geometry over count
Grind, hook, tooth material and sharpness change the cut as much as the number of teeth. Treat these ranges as a starting point, not a specification.

Sheet07

Plywood Thickness

Nominal Is Not Measured.

Answers
Is 3/4″ plywood really 3/4″?
Units
in · mm
Sheet
07 of 08

Plywood is sold by nominal thickness, but many sheets measure a little under it and some are made to metric sizes. Measure the sheet before you cut a groove to fit it.

Panel edges at true relative nominal thickness. Ply counts are illustrative — they vary by product and core type.
Nominal plywood thickness“Often measures” gives examples you may meet: the undersized fraction seen on many panels, and the nearest common metric panel. Actual thickness varies by product, grade and manufacturer.
NominalNominal (mm)Often measuresCommon uses
1/4″6.357/32″ (5.56 mm), or 6 mm metricCabinet backs, drawer bottoms, templates
3/8″9.5311/32″ (8.73 mm), or 9 mm metricLight panels, jigs and fixtures
1/2″12.7015/32″ (11.91 mm), or 12 mm metricDrawer boxes, backs, shop jigs
5/8″15.8819/32″ (15.08 mm), or 15 mm metricStiffer panels, bases, some shelving
3/4″19.0523/32″ (18.26 mm), or 18 mm metricCarcasses, shelves, tops
  • Cut dadoes, grooves and rabbets to the sheet you have, not to its label — a test cut in scrap settles it.
  • Hardwood and Baltic birch plywood are often made to metric thicknesses even when sold by inch labels.
Plywood and solid wood compared Estimate sheets for a project

Sheet08

Wood Movement

Across the Grain, Compared.

Answers
How much does it shrink across the grain?
Units
%
Sheet
08 of 08

Shrinkage from green to oven-dry, as a percentage of the green dimension — radially (across the rings) and tangentially (along them). Figures come from the same species data as the Wood Species library.

Shrinkage, green to oven-dry (%)USDA Wood Handbook averages; sapele from commonly published figures. T ÷ R compares the two directions: the higher it is, the more a flatsawn board tends to cup.
SpeciesRadialTangentialT ÷ RRadial and tangential drawn to scale
Black Walnut5.57.81.4
White Oak5.610.51.9
Red Oak4.08.62.1
Hard Maple4.89.92.1
Soft Maple4.08.22.0
Black Cherry3.77.11.9
White Ash4.97.81.6
Hickory7.010.51.5
American Beech5.511.92.2
Yellow Birch7.39.51.3
Poplar4.68.21.8
Eastern White Pine2.16.12.9
Douglas Fir4.87.61.6
Western Red Cedar2.45.02.1
Cypress3.86.21.6
Sapele4.67.41.6
Genuine Mahogany3.04.11.4
Teak2.55.82.3

A comparison, not a prediction

These figures compare species over the full range from green to oven-dry. Furniture never sees that range: seasonal movement in a finished piece is a small fraction of it, set by the humidity change the wood actually meets.

How wood movement works

Not listed: Iroko — no shrinkage figures in our species data.

Back on the Wall

Measure Once.Look It Up Twice.

Eight sheets for the numbers that come up mid-job. When the question is arithmetic rather than lookup, the calculators take over.

Back to Reference Index Use the Calculators