How do you measure the depth of a drill hole?
The use of step gages, “hard stops,” “flush pins,” Verniers, depth micrometers, CMMs, and even the piece of masking tape on the drill all have their place. The method used to measure the depth of a hole is greatly influenced by the tolerance and the design of the hole. No measuring tool works for every application.
How deep can a micrometer be used?
A depth micrometer will work down to about 1/4" diameter holes. The depth rod on most calipers will fit holes down to about 5/32". And you can always make your own gauge as suggested by others above. If it is going to be a permanent one, I would probably use music wire. OTOH, most drilled holes do not need to have a very precise depth.
What is a pin gauge used for on a drill?
Commonly known as pin gauges, use them to measure hole size and depth, check hole location and distance, and set micrometers. The black -oxide treatment on these no-go gauges shows wear patterns so you can tell when you need to calibrate or replace the gauge— they help you check the maximum hole diameter.
Which laser is best for measuring the depth of a hole?
These lasers are the ideal choice for the measurement of a hole’s depth. The Dimetix D-series laser distance series from Laser-View Technologies provides the best position sensors to achieve the following key characteristics: Small spot size: Approximately 0.15” spot size close to laser; grows to only about 2” size at 100m
How do you measure the depth of a hole?
When measuring the depth of a drilled hole, it is important to measure at the outside wall of the hole to obtain the depth of the full diameter portion of the hole (Figure 6). Hold the measuring rod next to the wall of the drilled hole to assure an accurate full diameter depth measurement.
What tools are measuring hole depth?
A depth gauge is an instrument for measuring depth below a reference surface. They include depth gauges for underwater diving and similar applications, and engineering instruments used to measure the depth of holes and indentations from a reference surface.
What measurement is used for depth?
A fathom is a unit of length in the imperial and the U.S. customary systems equal to 6 feet (1.8288 m), used especially for measuring the depth of water....FathomConversionsimperial/US units6 ftSI unit equivalent1.8288 m2 more rows
Where is hole depth measured to?
The bottom of the notch is the gage plane used to measure the depth of the hole.
What is depth micrometer?
A depth micrometer is a gauge used to measure the depth of holes, slots, and recesses. Depth micrometers feature a measurement rod that is inserted into the hole that needs to be measured. The rod is slowly lowered until it reaches the base of the recess.
Can you measure depth with a caliper?
With a caliper you can measure both inside and outside dimensions and depth: all you have to do is simply put the jaws against the object you need to measure, based on the measure you need to take.
How do you find a hole in the ground?
Round Hole Multiply the radius value by itself. For example, if the radius equals 4 feet, multiply 4 x 4. Multiply the resultant value by Pi (3.14). This is the measurement of the hole's base.
What is hole depth?
Hole Depth means the total depth of the Shot Hole to be drilled.
How do you measure the hole diameter in drilling?
A caliper log records the hole diameter measured using spring loaded caliper arms. Figure 9.2. 1 shows a variety of two, three, four, and six arm calipers. In general, the more arms, the more accurate the measurement of the shape and cross-sectional area of the wellbore.
What is used to check the diameters of holes?
Plug Gauges are used for checking holes in many different shapes and sizes.
What is the better instrument to use to measure the diameter of a hole?
bore gaugeA tool to accurately measure the diameter of any hole is known as bore gauge, It can be a scale, dial or digital type instrument.
How to measure a hole?
It can be as simple as applying masking tape to a drill or reamer to ensure the hole is deep enough, or as complex as the use of coordinate measuring machines and vision systems. The importance and applicable tolerance of the hole depth will dictate the accuracy and, in many cases, the method that is used to inspect the hole.
What is a depth notch?
The notches serve as a visual indication of the pass/fail inspection of the depth of the hole. As with all types of measurement, there are rules that need to be applied to ensure the accuracy of the measurement.
What is a square notch?
Square or flatted notches have a square or rectangular flat plunged into the diameter at a specific depth (see Figure 4). They function the same as the “whistle” notch. The bottom of the notch is the gage plane used to measure the depth of the hole. This design can be confusing. Some users question if the top of the square or flatted notch is also a measuring plane. Although it is done in some rare instances, most will use the bottom of the flatted notch as the gage plane.
What does a go notch mean on a plug?
The go notch would represent the minimum depth with the notch tolerance being applied, plus. The no-go notch would represent the maximum depth with the notch tolerance applied, minus.
How to tell if a plug gage is go or no go?
The go/no-go would have two notches representing both the minimum and maximum depth limits. When using go and no-go notches on the go plug gage the notches are ground 180° apart for plug gage diameters over .175” diameters. When the diameters are smaller than .175”, the notches are ground 90° apart. This is done to prevent the manufacture of the notches from weakening the plug gage and makes the notches more visible. Both the 180° and the 90° apposed notches allow the inspector to see both notches at the same time. If both notches are visible, the hole needs to be deeper. If the minimum (go) notch is not visible and the maximum (no-go) notch is visible, the hole depth is in tolerance. If both of the notches are not visible, the hole is too deep.
What is a depth notch on a go plug?
The notches serve as a visual indication of the pass/fail inspection of the depth of the hole.
What causes a blind hole to be a problem?
Radii or chamfers in the bottom of a blind hole can cause problems if not accounted for properly. A large radius or chamfer in the bottom of the hole will prevent the plug gage from reaching the bottom. If you have a large radius or chamfer in the bottom of a blind hole, you may need to have a larger chamfer ground on the plug gage. This larger chamfer will clear the corner chamfer or radii in the bottom of the hole. This then allows you to measure to the bottom of the hole. Attention to how the depth of the hole is noted on the drawing is critical. If the depth of the hole were dimensioned to the top of the radius, the above example would be in tolerance without the large chamfer. The gage stops at the top of the radius, not the bottom of the hole.
What is the other aspect of depth micrometers?
The other aspect of the depth micrometer, which must always be kept in consideration, is that it reads in reverse from other micrometers (Figure 3).
How accurate is a depth micrometer?
The depths of holes, slots, shoulders, and projections can be measured accurately to within 0.001 of an inch.
How many inches does a depth micrometer move?
The head movement of the depth micrometer is one inch. Whenever you use the micrometer, with the existing rod or to different length rods, check the accuracy of the depth micrometer against a known standard (Figure 5).
How many points are needed for depth micrometer?
When using a depth micrometer, two points must be kept in mind. Depth micrometers measure from a reference plane to a point. The large base of the depth micrometer (Figure 2) makes up the reference plane. The very small area of the measuring rod makes up the point of contact.
Do you need to move a depth micrometer?
When using the depth micrometer, there is no need to move the micrometer around to attain the proper feel. In fact, sliding the micrometer should be avoided. The small rods will wear very quickly and the accuracy of the micrometer may be lost. For greater accuracy, take several readings at slightly different positions.
How to measure depth of holes, slots, shoulders, and projections?
Measure the depth of holes, slots, shoulders, and projections by changing out the steel extension rods supplied in 1" incremental lengths.
What gauges are used to measure hole diameter?
These Class Z no-go gauges help you check the maximum hole diameter. Commonly known as pin gauges, use them to measure hole size and depth, check hole location and distance, and set micrometers.
What gauge do you use for a hole?
Use these metric Class X plug gauges for precision go/no -go measuring of hole sizes and depths, checking hole location and distance, and setting micrometers. They’re also called pin gauges.
What is a tenth step gauge?
Also known as tenth-step gauges, they’re often used in metrology labs, quality control departments, and tool rooms for setting snap gauges and comparators.
What is black oxide on a no go gauge?
The black -oxide treatment on these no-go gauges shows wear patterns so you can tell when you need to calibrate or replace the gauge— they help you check the maximum hole diameter.
What does a notch on a handle mean?
A notch on the handle indicates when the internal NPT threads you’re checking are in tolerance.
How deep can you measure with a connectable rod?
Measure depths up to 8" using connectable extension rods.
How to measure a hole?
It can be as simple as applying masking tape to a drill or reamer to ensure the hole is deep enough, or as complex as the use of coordinate measuring machines and vision systems. The importance and applicable tolerance of the hole depth will dictate the accuracy and, in many cases, the method that is used to inspect the hole.
What is a depth groove?
Depth grooves function as depth inspection tools as well (see Figure 5). These also have advantages and limitations. In the case of the depth groove, the bottom of the groove acts as the minimum (go) depth and the top of the groove represents the maximum (no-go) depth. The nice thing is that you have a groove that goes around the circumference of the gage. The user does not need to rotate the gage in the hole to see the notch as you would with a “whistle” or “flatted” notch. Depth grooves are limited in their width by the ability of the gage manufacturer to produce and inspect them accurately. The minimum width limit for grooves is usually approximately .025” wide. Depth grooves should not be used on small diameter pins. Each gage manufacturer may have slightly different limitations but, generally anything less than .175” in diameter will be a challenge. The other issue with these smaller diameters and grinding depth grooves is the depth of the groove on the gage. If too much material is removed, usually to make the groove visible, the plug gage can become brittle and bend or break. In this situation, a broken gage is better than a bent one. The bent one is no longer accurate.
What is a square notch?
Square or flatted notches have a square or rectangular flat plunged into the diameter at a specific depth (see Figure 4). They function the same as the “whistle” notch. The bottom of the notch is the gage plane used to measure the depth of the hole. This design can be confusing. Some users question if the top of the square or flatted notch is also a measuring plane. Although it is done in some rare instances, most will use the bottom of the flatted notch as the gage plane.
What causes a blind hole to be a problem?
Radii or chamfers in the bottom of a blind hole can cause problems if not accounted for properly. A large radius or chamfer in the bottom of the hole will prevent the plug gage from reaching the bottom. If you have a large radius or chamfer in the bottom of a blind hole, you may need to have a larger chamfer ground on the plug gage. This larger chamfer will clear the corner chamfer or radii in the bottom of the hole. This then allows you to measure to the bottom of the hole. Attention to how the depth of the hole is noted on the drawing is critical. If the depth of the hole were dimensioned to the top of the radius, the above example would be in tolerance without the large chamfer. The gage stops at the top of the radius, not the bottom of the hole.
What is the chamfer on a plug gage?
If they are too large, the radius or chamfer will allow the gage to seat on the transition angle between the two holes .
What does a go notch mean on a plug?
The go notch would represent the minimum depth with the notch tolerance being applied, plus. The no-go notch would represent the maximum depth with the notch tolerance applied, minus.
Why are plug gage notches 90 degrees apart?
This is done to prevent the manufacture of the notches from weakening the plug gage and makes the notches more visible. Both the 180° and the 90° apposed notches allow the inspector to see both notches at the same time.
What is depth mike set?
Typical depth mike "set" is one head, and a collection of swappable rods.
What does a mic tip on a hole mean?
A tip on your depth mic smaller than the hole gives a number in between sitting on the taper of a drilled and the floor of bored.
Do you need to grind a hole size pin?
Min hole size pins are a great idea but sometimes you need to grind the drill point angle on your measuring pin.
Is a depth rod hard?
Depth range is usually not so hard. Common calipers have a depth rod. Practicality depends a great deal on what you mean and need as to "small" in diameter. Cheap and dirty for fewsies when the depth measuring tool is too fat to use directly, can be a used "gage pin" set for-not-so-deep, or a bundle of blued HCS "clock steel" or cheap "thread ...
How accurate is a laser microscope?
By using laser scanning microscope you are able to measure depth by several tens of nm accu racy.
Can electron microscopes see holes?
I think this small dimensions will never be seen by optical microscopy. Only electron microscopes are able to see. This is possible from scientific view point. I think the problem is technical. I mean how to measure with electron microscope. I suggest to make a thin film of transparent polymer over the surface you made drilling for. This film will have a negative form of the hole (Rod Shape) in the sample for which you can measure the height of the rod.
Can you measure the depth of a hole under a microscope?
If it could be possible, make some holes with the same laser parameters with overlapping and break the substrate. The depth could be measured easily under microscope.
Can you see the ground with a large aperture?
Large magnifications and thus large numerical aperture us will not be able to see the ground. If all you need to see is the depth I would recommend medium magnification with small NA. A good WLIM might be your best bet.
