Layout Tools
Last updated on Wednesday, January 18, 2012 06:58:23 PM Eastern US Time Zone

Layout Tools, Scribes & Automatic Center Punches, Precision Gage Blocks, Surface Plates,
Surface Gages, Height Gages, Universal Gage, Transfer Punches, Protractor, Optical Protractor

Also refer to, how to drill a hole where you want it & how to drill the center of a rod.

Layout Tools

Various types of squares, small rules, & protractors. Starrett (USA) & Mitutoyo (Japan) are high quality.

Satin chrome finish, machine-divided blade, hardened steel, Starrett rules.

Starrett Model No. 289A combination square blade attachment.
This accessory allows attaching a steel rule at right angles to another rule or the blade of a square.


Accepts 1" (25.4mm) wide blades. Attachment seat lengths: blade 1-9/16" (40mm) x rule 1-11/16" (43mm).

LS Starrett invented the combination square. These are hardened & ground models.

Top row are two Machinist's solid squares: hardened (RC55), ground, & lapped to high accuracy.
Bottom center is a Starrett toolmakers double steel square & its extra blades.

Outside calipers, spring divider, hermaphrodite, & inside calipers.

Scribes & Automatic Center Punches

Scribes & automatic center punches. Top to bottom: Starrett surface gage steel scribe, a diamond-tipped
 scribe, a carbide-tipped scribe, two large-body punches that make deep marks, two high-precision punches
 that have very fine sharply pointed replaceable tips, & the last punch has small replaceable tips.

Automatic center punch exploded detail. Assembly order is left to right, top to bottom. If the middle row far
right cylindrical part is turned around, the punch will not work properly. The flat side faces the point & the
curved side faces the hammer/ball bearing.
Center punch assemblies: General No. 87  thin body, No. 70079  large aluminum body, & No. 78 steel body.

Automatic center-punch replacement tips. Lower-left: General No. 79P.

Precision Gage Blocks

81 piece, Grade B, hardened, precision gage block set, from 0.050 to 4.0",  ±0.000050" at 20°C (68°F).
Excellent for use with height gages, depth gages, sine bars, sine plates & sine vises, setups, etc. (import)
Example of a calibration reference table. See Starrett for information on wringing gage blocks.

Spacer gage set.  Used for setting stops, setups, & sine bars.

The ends are threaded so they can be screwed together/stacked.


Accurate, 1-2-3, 2-3-4 & 2-4-6 (inches) precision-ground, hardened, steel blocks.
⅜-16 threaded & clearance holes allow clamping. Handy for surface-plate measurements & mill setups.

Surface Plates

Granite surface plates (± 0.0001") in 18"x12"x3" (85 lbs.) & 12"x9"x2" (30 lbs.) sizes.
The relatively heavy plates have Teflon pads on the bottom to ease movement on the bench.

 

 
A simple, all wood (glued only, no metal) cover to protect the surface from damage.

Surface Gages

Universal Starrett surface gage holding its hardened steel scribe.
Base is 2-13/16" (L) x 2⅜" (W) & is supplied with 9" & 12" spindle lengths.
Starrett Model 257 exploded diagram.

The base has a V-groove for centering on round parts. The pins extend to act as guides along an edge.

Starrett surface gage & Interapid dial test indicator on the granite surface plate being zeroed
 using a 1" gage block. If possible, move the part not the gage when measuring a surface.

For highest accuracy, the angle between the stylist & part surface should be as close to 12° as possible.

The wide-range (±0.060") Interapid held by the rigid, precise Starrett is a nice combination on a surface plate.

 Starrett Model No. 56 toolmaker's surface gage. The small size helps when working in tight locations.
The base is 2⅛" (L) x 1⅜" (W) x ⅞" (H) & the spindle length is 4 inches.
Starrett No. 56 surface gage parts diagram.

Found this old gage at a tool sale for $10. Purchased a new scribe from Starrett to complete the restoration.

The universal & toolmaker's surface gages compared for size.

Height Gages
  
A Mitutoyo, 8", 543-244 digital height gage with fine adjustment mechanism. The height gage & a granite surface plate make an accurate
combination for measuring parts or laying out precisely scribed lines. Resolution: 0.0005". Absolute electrostatic capacitance type linear encoder.
A fine adjustment carriage is a requirement for fast, accurate settings. See Mitutoyo 543-244 digital height gage manual & dimensional drawing.
For accurate, repeatable measurements, insure the surface plate, height gage, & scribe working surfaces are free of debris/grit.
Check to see if the scribe bracket is tight. Periodically inspect the adjustable ways of the transducer for excessive play.

The heavy base has an excellent ergonomic design. The bottom surface is ground & lapped to perfection.

Mitutoyo depth & center-finder attachments for the height gage.

Hole center-finder attachment.

Hole center finder animation showing how the fine adjustment of the height gage is used to zero the needle.

Height gage with digital indicator for both height & tolerance measurements.

  
A carbide-tipped (Mitutoyo) 10", dial height gage on a granite surface plate (± 0.0001"). High accuracy can be achieved using gage blocks to set specified heights.
Use layout die to make the scribe marks easier to see. Mitutoyo height gage manual. Surface plates are useful for precision alignment when assembling parts, too.

Depth attachment. Rod accepts different 4-48 threaded indicator points. This was my first height gage.
It is easier to miss-read an analog dial than a digital readout though analog scales can be interpolated.

Measuring distances between holes using a center-finder attachment from Mitutoyo.

Height gage with digital indicator for both height & tolerance measurements.

Using a test gage in conjunction with a height gage allows measurements of both dimensions & tolerances
without having to use separate instruments. See instructions on how to set tip geometry & see illustration.

Mitutoyo OEM wooden case.

Starrett No. 3751 digital height gage. Auto-off in 5 minutes but retains zero; auto-on when the slide is moved.
Zero to 6.45" max range, 0.0005" (0.01mm) resolution & ±0.001" (± 0.03mm) accuracy. Supplied with an extra
scribe & clamp plus an excellent, padded, aluminum hard case. The vertical column is set-in from the tip
of the base's nose for better stability. Zero is saved between uses. This height gage's compact size is
especially valuable when measuring parts with very small features or using it on my two mills. The scribes
are not carbide-tipped. The fine-edged, HSS scribes are limited to semi-hard metals & the rounded tips
limit scratch depth. This height gage is ideally suited for use on small, delicate work.

Starrett No. 3715 digital height gage manual.

Adjusting to a specific height can be accomplished by picking it up & using it much like a regular caliper.
 Slightly increasing the slide resistance of the transducer (a small, side setscrew) helps adjustability.
Setting an exact numerical value with this type of adjustment mechanism is slower than
that of a height gage equipped with a fine adjustment carriage mechanism.

A Starrett Last Word DTI mounted onto the small, 3715 height gage using the 711-49 attachment.

Universal Gage

Starrett No. 995E (USA) Universal Precision Gage set is best in class. This gage has multiple uses:
height gage, scriber, planer/shaper setup, an adjustable parallel to measure a gap, transfer
measurements, precision level, & layout work on a surface plate using gage blocks or a sine bar.
Starrett  Model No. 995E Universal Gage exploded diagram.

Nominal dimensions of the base are 5.25" x  2.5" x 0.75" (W x H x D). Hardened & precision ground.
The slide has a combination of both a flat & a V-way to provide excellent accuracy.

The slide has a fine adjustment mechanism allowing faster & more accurate settings.
No other similar gages have this important feature. Note the mineral spirits bubble level.

Offset attachment with clamp bolt extends the nose for a minimum height of 0.17" allowing use in tight areas.

One-inch & three-inch extension rods can be screwed in at four different locations.

A toe clamp holds a hardened HSS scribe which is shown being set at 3.0000" height using a gage block.

A Starrett Last Word DTI mounted onto the 995E Universal Gage using the 711-49 attachment.

Transfer Punches

Transfer punch sets: Fractional - 3/32" through 1" by 1/64th", 0.0025" undersized.
Numbered - 1 through 60.  Lettered - A through Z.  Metric - 1mm through 13mm by 0.5mm.
 Black anodized & heat treated. Some of the original stands were replaced with Huot brand.
Note: import punches sometimes have off-center tips that need to be corrected using a lathe tool-post grinder.

The supplied stand for the metric transfer punches was of very poor quality so an aluminum stand
was fabricated. The plates' dimensions are 5¾" x 2⅝" x 1/3" thick & the bottom plate is 1/16" thick.
A thick top plate keeps the punches vertical plus easier to take them in & out than the multi-plate designs.
The holes were made using each bit of the entire set of metric drills; the transfer punches are undersized.
After the plate was drilled, the top surface was fly cut & then the holes chamfered to make a nice finish.
1⅛" long, 4-40 steel standoff posts were used as spacers. The bottom plate corner holes were first threaded,
the posts were then screwed in followed by a nylon-insert lock nut that secures the post & acts as the feet.


Integer sizes were stamped onto the top & filled-in with black China marker.


Transfer screw sets for mating parts especially blind holes. Hardened screws stored inside handle.
Handle end has a hex driver that serves as wrench. Top to bottom examples: ¾-10, 4-40 & M10-1.5 (metric).

A metal holder for the transfer screw sets. The hardware: ¼-20 cap-head bolts, brass tubes, & lock nuts.

The lower plate has corresponding holes that capture the tips. The lock nuts also function as feet.

Modified the holders where ¼-28 bolt heads now act as feet.
 

Holders for metric (L) & Imperial (R) transfer screw sets. Similar design to the Silver & Deming drill bit stand.

Protractor

Accurate, all-metal protractor set.

There is an etched degrees scale with a 5 minutes precision vernier (nonius) scale.
 If the magnifier is needed, the two screws are used for attachment.


Scale as seen while under the magnifier accessory. This scale is reading at 0°5' angle.

Plastic protractor. General No. 29 instructions.

Optical Protractor

An optical protractor that is excellent for ergonomic analyses of workstation display & control geometries.

OPTO-METRIX Optical Protractor OP-1a. US Patent No. 4,257,164.

Layout Tools, Scribes & Automatic Center Punches, Precision Gage Blocks, Surface Plates,
Surface Gages, Height Gages, Universal Gage, Transfer Punches, Protractor, Optical Protractor