Dial bore gauge allows you to measure the internal diameter of a cylinder hole with better speed and accuracy.
As the name suggests, it comes with a dial indicator to display the reading in real-time. The long shaft lets you reach the internal diameter down the deeper area.
Since it’s used to measure the hole’s diameter, this tool is commonly used by machinists and engine builders. One of the common applications is for engine building. It’s used to inspect the taper, oversize, and out-of-round of an engine’s bore. You get more accurate, easier, and faster measurement rather than using a telescopic gauge.
Having the best dial bore gauge is an excellent investment in your machine shop.
If you are looking for a new dial bore gauge to buy, then this post is made for you. The following contains 6 dial bore gauges that you could purchase online. Read the reviews plus the buying guide and see what we suggest.
Top 6 Best Dial Bore Gauges
1. Mitutoyo 511-932 Dial Bore Gauge Kit [Best Overall]
The best overall dial bore gauge that we find on the online market is Mitutoyo 511-932. It is able to provide a wide range of measurements, a high degree of accuracy, a high resolution, smooth operation, and a requestable NIST certificate.
This Mitutoyo 511-932 is a kit that contains: 3 bore gauges (Mitutoyo 511-731, Mitutoyo 511-732, and Mitutoyo 511-733), a single dial indicator (Mitutoyo 2923SB-10), 26 anvils, 10 spacers, and other pieces of equipment.
Those 3 bore gauges are selectable to assist you in measuring within the range of 0.7″-6″. So, it’s versatile for many purposes. The resolution of the dial indicator is awesome, 0.0001″. While the accuracy is also excellent, ±2µm (0.00008″).
It comes with a carbide-tip ball on the anvil for better abrasion resistance. Moreover, it’s designed with a hollowed-structure grip that is also important to reduce heat transfer by 50%. Mitutoyo is known for its quality products’ smooth operation. It’s the same with this one.
A high degree of accuracy is important for a serious project. It should be backed up with a trusted certificate. If you are looking for a serious measurement, you could purchase it with the certificate of traceability to NIST.
- Excellent accuracy (±2µm / 0.00008″)
- Awesome resolution (0.0001″)
- Large range of measurement (0.7″-6″)
- NIST certificate can be requested
Read the manual on the following pdf file:
2. Fowler 52-646-500-0 Dial Bore Gage Kit [Best for Budget]
You could use it for a wide variety of purposes since the measuring range is 1.4″-6″. It should be sufficient to cover many things. There are two measuring heads: one is designed for the 1.4″-2″ range and the second one is designed for the 2″-6″.
The anvils are carbide-tipped which are a must for last use. In addition, it comes with a one-year warranty.
If you are on a budget but require the nice one, Fowler 52-646-500-0 is the right choice to pick. Its range is decent. Since the smallest diameter of a bore’s engine that we know is about 50mm (1.9685″), while the smallest diameter it can measure is 1.4″, this one is more than enough to cover your measurement.
- Awesome resolution (0.0001″)
- More than enough of the measurement range (1.4″-6″)
- Affordable considering the spec
- Not know about the accuracy
3. Mitutoyo 511-753 Dial Bore Gage
It provides a find accuracy which is 2µm (0.00008″). This model comes with 11 anvils (2″ sub anvil) and 4 spacers.
However, it only covers the range from 2″ up to 6″, shorter than the 2 models above. Nevertheless, this range is actually sufficient to measure most diameters of the bore’s engine.
So, when you are on a budget but trying to get a dial bore gauge from Mitutoyo brand, then this is the choice.
- Great 0.0001″ resolution
- The range is for most diameters of bore’s engine (2″ – 6″)
- Fine accuracy (2µm=0.00008″)
- Pretty expensive
4. Accusize EE20-1006 Dial Bore Gauge
However, its accuracy is ±0.0004″. Considering the price, it should be reasonable.
It comes with one bore gauge, one dial indicator, a set of 11 anvils, and a 6-inch length stem. This is not the recommended choice from us but if you think that you don’t need a high degree of accuracy requirement, this one is a nice choice.
- High resolution
- Lower accuracy (±0.0004″)
5. Anytime Tools AT207770 Dial Bore Gauge
The measuring range that it can cover is good which means versatile for a lot of purposes. It’s able to cover the diameter from 0.7″ to 6″. Therefore, it comes with 3 measuring heads. Each measuring head covers a specific range: 0.7″-1.5″, 1.4″-2″, and 2″-6″.
Moreover, the resolution of the dial indicator is 0.0005″. It comes with a yellow background which should be an advantage in a low-light environment when taking a measurement.
In addition, if your engine bore is deep, the diameter you are going to measure is located at down to 10″, don’t worry, it’s able to cover it. However, it’s sorry to say that there is no information about the accuracy that we could put in here. All in all, considering the price and spec, we decide to share this with you.
- Wide measurement range (0.7″ to 6″)
- Decent resolution (0.0005″)
- No information about the accuracy from the company
6. Fowler 54-646-401 Digital Bore Gauge Set
Fowler 54-646-401 lets you read the measuring result in the shape of a bar graph and numbers. Herewith, you can quickly know the span you made and, most notably the smallest reading.
On the screen, you can instantly change the measurement unit either inch or millimeter. Setting the desired zero point is only a matter of a click.
There are 5 functional buttons. The red one which is the Zero/On button is to turn on or off the digital indicator. The In/mm is to convert the unit reading. While the ABS/SET is to adjust the zero point at the position you want. MIN is used to start calibration. Lastly, the CAL button is used during the calibration. More about this, you can read the manual.
Its measuring distance is sufficient to cover many purposes as it is from 1.4″ up to 6″. There are two measuring heads that you can change as you need. The smaller one is made for the anvil range of 1.4” to 2.0”. In comparison, the larger one is meant for the anvil range of 2 to 6”.
Like many digital products, this one uses a CR2032 battery. If you want to measure the cylinder bore, taper, and the out-of-round, this digital bore gauge can make your way different.
- Digital model which means easy and fast to read
- Easy to set up the zero point
- Always need battery power to operate
Things to Consider Buying A Dial Bore Gauge
Surely, this is the critical factor to consider to gain an accurate measurement. Accuracy shows how reliable your measurement is.
To have some peace of mind, you may want to rely on the product accuracy to the NIST standard. Herewith, you send the product to NIST in order for them to calibrate it and send you the calibration result. In some products, they also provide this service. That means you purchase two items. One is the product, and then the second is the calibration service. Then the bore gauge comes to you with a certificate of calibration from NIST.
As we know that NIST stands for National Institute of Standards and Technology, an institute in the USA. You could let your bore gauge calibrated by their standard.
The smallest readout given by the dial indicator is called resolution. Using a high-resolution dial bore gauge lets you determine the level of roundness of an internal hole. A very small diameter difference can be measured with a high resolution.
In engine building, it’s recommended to pick a 0.0001-inch resolution dial bore gauge to measure the clearance accurately. However, basically, a 0.0005-inch model can serve with adequate results.
The measuring range is also important. It determines how capable your bore gauge to measure the bore diameter. When considering this factor, it means you also consider the set of anvils that come with the purchase.
This page shows you the bore and stroke dimensions of several engines. The bore dimension lets you know the diameter of the engines. Herewith, you can guess your range requirements.
In our perspective, the best range to cover most jobs is 0.7″ to 6″. However, if it’s from 1.4″ to 6″, it should be enough to use.
4. Carbide Tipped Anvil
Like the micrometer, the carbide-tipped anvil is helpful to fight against wear for a lot of uses. Especially the anvil, the part that mostly gets contacted to the object being measured.
Dial Bore Gauge Body Parts
To get a thorough understanding of a bore gauge, you may need to learn its body parts. These are several major parts of a bore gauge.
- Dial Indicator. This is the part where you can view the measuring reading. It can be a digital indicator as well depending on your preference to use.
- Screw. The dial indicator can be changed with another dial indicator. To do that, just unscrew this part to untighten and you can replace it.
- Grip. The part where your hand is put to control the bore gauge.
- Measuring head. Go down and you’ll find this part. This part consists of several sub-parts such as the anvil and the centering contact.
- Anvil. Anvil the part that contacts the bore’s wall. There are two anvils: the interchangeable anvil and the moveable anvil.
- Interchangeable Anvil. You can replace it according to the diameter of the bore you want to measure. As usual, a set of dial bore gauge comes with a set of anvils.
- Moveable Anvil. This is a fixed anvil but it’s not able to get substituted.
- Centering Contact. Another part that contacts the bore’s wall is called centering contact. This part guides the anvil in the right position.
Electronic and Wireless Bore Gauges
The bore gauge doesn’t always come with a dial indicator model.
The speed demand over the bore gauge comes in. Electronic and wireless bore gauge can help. This gauge doesn’t come with a dial indicator, but a digital indicator. The rest is the same.
You need to take the reading as usual.
A wireless bore gauge allows you to transfer the reading in real-time to another device such as a tablet or pc or smartphone. Doing a lot of measurements can be a short period of time because you are not required to put the reading results on the note.
However, a digital wireless bore gauge may be so expensive. If time is your matter, then this is the problem solver.
So, when you need to measure the inner diameter of an engine bore, you could use between these options: telescopic gauge, bore gauge, and 3-point bore gauge. However, using the bore gauge gives you some advantages in terms of accuracy, speed, and price. It provides good accuracy while maintaining the price at an affordable point. Despite the 3-point bore gauge can serve the reading faster than the bore gauge, the bore gauge’s speed is not too bad (actually good).
Another advantage of a dial bore gauge is the changeable dial indicator that is installed at the top of the bore gauge. By changing it with a digital indicator, you have a chance of getting more speed by transferring the reading to a computer (wireless model). So, there is no need to note the reading on a piece of paper anymore. If you prefer the digital indicator, make sure the digital indicator being used also displays the visual reading similar to that the dial indicator has.
Finally, we recommend Mitutoyo 511-932 dial bore gauge kit. Although it’s expensive, the accuracy and resolution that you get from this Mitutoyo product are unbeatable so far compared to other dial bore gauges. Besides, its measuring span is also excellent. All in all, this is what we recommend available on the market if you don’t matter about the price.