How To Read a Micrometer
(More customer reviews)I was ready to return this until I finally figured out that you have to spin the nut at the top of the ‘snake arm’ to adjust the length of its internal cable before turning the clamp arm at its base (because it is a slightly different length depending on how it is positioned).
NOTE: there are NO MANUALS at all with any of the three items that come with this!!!
Its not too complicated once you figure it all out, but it too me a while.
The snake arm thing seems like it holds quite well. I saw the reviews for the regular straight arm indicator holders complained of breaking plastic wing nuts so I thought I’d get this one and am glad I did.
The set of tips are ok but don’t seem like I will probably use them except the one angled one. I was hoping one of the tips would have a wheel but none do.
The magnetic base is typical ‘chinese cheep’ but functional. It sticks well to thick metal but not to thin / curved metal (like the body of a car).
The dial indicator is quite smooth in its operation. I don’t see any way to adjust or zero it (but I don’t know if a good indicator would have this either). There is a button thing on the indicator that I can’t figure out what it is for (I can unscrew it, but it is not a replacement tip).
Click Here to see more reviews about: Anytime Tools DIAL INDICATOR + FLEXIBLE ARM MAGNETIC BASE + POINT SET
Click here for more information about Anytime Tools DIAL INDICATOR + FLEXIBLE ARM MAGNETIC BASE + POINT SET
How to Read a Metric Micrometer
When measuring things like the inside radius of a tube or the diameter of a sphere, a micrometer will give you a very accurate result. The most common type of micrometer, the screw gauge, has precisely machined threads in the handle that are used to advance and retract a shaft, or spindle. When the spindle is advanced, the number of turns or partial turns on the threads is measured using a gauge stamped into the handle. This gauge can be in either English or metric units.
Set the micrometer on the object to be measured. For inside micrometers, this means it is stretched across the inner diameter of the tube or pipe, and for a depth micrometer, it means it is resting on the rim of the bowl or channel and the spindle is resting on the bottom. For an outside micrometer, the object being measured should be lightly held between the spindle and the anvil.
Use the micrometer’s locking mechanism to hold the shaft in place. This will most likely be a thumb lever or thumb wheel located near the spindle.
Read the linear gauge, which is in millimeters, and then read the barrel gauge. The barrel gauge will be divided into increments depending on the step size of the linear gauge. For metric micrometers that use millimeters in half-step increments, the barrel gauge will have 50 increments. The barrel gauge is abbreviates so that «28» equals 0.28 mm.
Combine the two readings. A reading of «5.5» on the linear gauge and «28» on the barrel gauge equals a total of 5.78 mm.
Use a vernier scale. The scale goes from 0 to 10. The increments are spaced so that only one increment will perfectly align with the barrel gauge at a time. Whichever line aligns with the barrel gauge, regardless of which number it aligns with, is the next digit in the measurement. A reading of 5.78, with a vernier reading of «3» equals 5.783 mm.
Sliding caliper micrometers also use a vernier scale and are read in the same way.
Micrometers are very precise and very sensitive to heat, cold and impact. Treat your micrometer with care.
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How to Read a Micrometer – Micrometer Reviews
So, you want to learn how to read a micrometer. What’s the first step? If you’re just starting out, you may find that reading a micrometer can be tricky. I remember it took me a while to catch on. However, once you get the hang of it, you’ll be able to record accurate and precise measurements in no time.
By the end of this article, you’ll learn the correct way to take a measurement. You’ll also be able to read a standard micrometer, as well as a digital micrometer. If you have any additional questions, feel free to contact us!
Let’s get started.
Learn the different parts of your micrometer
If this is your first time using a micrometer, you’ll want to familiarize yourself with the different parts. Each micrometer can be broke up into the following parts:
- Thimble Lock
- Thimble Scale
- Ratchet Stop
Position the material
Carefully place the material between the anvil and spindle. Pay attention to the placement of the material. Turn the thimble until it the anvil is about to make contact with the material.
Turn the ratchet
Gently place your fingers on the ratchet and turn. This makes sure the anvil and spindle are flat against the object.
Listen for the clicks
Once the material is secure between the anvil and spindle
If your micrometer is equipped with a thimble lock, now is the time to set it. This locks in your measurement reading. If you happen to bump your micrometer at anytime, your measurement should still be intact.
Carefully remove the material from the micrometer. If you are measuring something small, you can slide the material away from your micrometer. If you are measuring something larger, it may be easier to pull the micrometer away instead.
How to Read a Micrometer
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Measurements taken with micrometer are a combination of the value shown on the sleeve scale and the value indicated on the rotating sleeve scale.
When using a micrometer with an additional vernier scale, the value on the vernier scale may also be taken into account.
Step 1 — Look at sleeve scale
The value of the first signficant figure of a measurement can be found on the sleeve scale.
This will be the number immediately to the left of the thimble.
On a metric micrometer, this will be given in millimetres. Each minor increment on the sleeve scale represents 0.5mm.
In this example, the reading on the sleeve scale is 6.5mm.
Step 2 — Look at thimble scale
Then, read the value shown on the thimble scale.
The thimble scale of a metric micrometer has a range of 0.5mm (one complete revolution), with each increment representing 0.01mm, and usually numbered in 0.05mm steps. The value is the lowest number that aligns best with the index line on the sleeve scale.
If the index line falls between two values, the reading will be the number immediately below the index line.
If this is the case, you should estimate the final part of the measurement or, if your micrometer has one, consult the vernier scale.
Here, the thimble scale is showing 0.11mm.
Step 3 — Look at vernier scale
If you have a vernier micrometer, you may next read the value indicated on the vernier scale (if you don’t have a vernier micrometer or don’t require the accuracy, go to Step 4).
The vernier scale of a metric micrometer has a measuring range of 0.01mm and is graduated in 10 increments. Each increment represents 0.001mm.
The reading on the vernier scale is the value that aligns best with any increment on the thimble scale (0.009mm in the image on the left).
Step 4 — Add values together
To get your total reading, add the values from each of the scales together (sleeve + thimble ( + vernier) = measured value).
e.g. 6.5mm + 0.11mm = 6.66mm.
Because the reading on the thimble scale fell roughly halfway between two values, we can estimate that the reading is in fact, 6.665mm.
A vernier scale, however, would provide the smallest part of the measurement (0.005mm in this case) more accurately.
How to Read an Inch Based Micrometer
How to Read an Inch Based Micrometer
· How to Read an Inch Based Micrometer ·
Reading an inch based micrometer by using the four step addition method explained here is a relatively easy process. The first set of instructions apply to micrometer movements used on outside and inside micrometers. The second set of instructions apply to depth micrometers.
Basic Micrometer Movement
The illustration above shows a basic micrometer movement as used on outside and inside micrometers. The thimble rotates relative the barrel on a threaded shaft that has 40 threads per inch. Therefore one complete revolution of the thimble moves it axially 1/40th, or .025 inch. The barrel scale is divided into increments of .025 inch, with each .100 inch numbered for convenience. The thimble scale is divided into increments of .001 inch, with each .005 inch numbered around the thimble as 0, 5, 10, 15, and 20.
The following example is presented to illustrate the four step addition method. To read the indicated value, proceed as follows:
Step #1. Record the whole number that represents the minimum size the micrometer could read. Assume the illustration above is on a 3 to 4 inch outside or inside micrometer. Write it down as shown here:
Step #2: Using the end of the thimble as an index line, record the whole number of .100 inch increments to the left of the index line. The illustration above shows that there are seven .100 inch increments to the left of the index line, which equals .700 inch. Record this value as shown:
Step #3: Still using the end of the thimble as an index line, record the whole number of .025 inch increments to the left of the index line. The illustration above shows that there is one .025 inch increments to the left of the index line, which equals .025 inch. Record this value as shown:3.000
Step #4. Using the axial line on the barrel as the index line, read the number of the .001 increment from the thimble that is closest to the index line. The illustration above shows that there the mark representing sixteen lines up with the index line, which equals .016 inch. Write it down as shown here:3.000
Now add up the four digits to obtain the correct reading:3.000