In the realm of automotive repair, there are occasional times that you need the ability to precisely measure components. For many applications, a steel rule or a tape measure is good enough if you don’t need accuracy. However, if you are doing things like measuring wear on your brake rotors, sizing valve shims, or doing machine work you may find that these tools allow for too much variation to get an accurate measurement. When this is the case, you need a higher precision tool, and a dial caliper works great for this application.
When it comes to calipers in general, there are multiple types. The three most common are dial calipers, digital calipers, and vernier calipers. Between the three, each has their tradeoffs. Vernier calipers are simple and require minimal calibration. Digital calipers are easy to read and offer some advantages in terms of showing measurements using multiple different units but at the cost of having to replace batteries occasionally. The dial caliper has been the long time favorite of many because of the off angle visibility as well as the fact that they are entirely mechanical.
Perhaps the two most important facets to consider when assessing the quality of a precision measurement tool are accuracy and materials. The accuracy rating on the tool is obviously extremely important because after all, you are buying the tool to take accurate measurements. Materials are also important as tools made with cheap materials can fall out of calibration more quickly due to material degradation. Design can compensate for this a little bit but it has limitations.
The Best Dial Caliper
Starrett 3202-6 6″ Dial Caliper
As far as the best dial caliper value, we give the nod to the Starrett 3202-6 6″ dial caliper. Starrett has a long history of making fantastic precision measurement tools and other calibrated tools, and they are well known for their quality.
The 3202-6 caliper has a number of nice features that set it apart from the other calipers on the market. Measuring accuracy is +/- .001″ which is standard for a caliper this size. This is accurate enough for most projects on your car, although if you need even higher accuracy you will need to get a micrometer (which Starrett also makes). The caliper can be had with or without an NIST cert (which comes at roughly a $50 premium if you need it…it’s something typically required for manufacturing quality systems in industry so we advise that a home mechanic skip it to save the money).
As far as construction, the tool is made from hardened stainless steel which means that both pairs of jaws (both internal and external) can withstand minor bumps and bangs. The dial rotates so the caliper can easily be zeroed out and can be locked in place once set with a small thumb screw. The sliding jaw also contains a locking thumb screw so that you can secure it once you have made a measurement if you so choose. The sliding jaw also comes equipped with a thumb wheel that lets you make micro adjustments when opening or closing the jaw.
The edges of each jaw are chamfered (Starrett calls these “knife-edge jaws”) which helps improve accuracy when you need to measure in a small groove or on a rounded surface such as the inner diameter of a tube. The Starrett 3203 also has a depth probe to allow you to measure a depth where the jaws aren’t able to access. Finally, they come with a molded foam lined case to protect the tool when not in use. Overall, this is the best caliper value around and we think you will be extremely happy with them.
Brown and Sharpe 6″ Caliper
As a runner up, we also really like Brown and Sharpe’s line of calipers (these are the ones we have personally used for years) due to the easy to read high contrast dial (especially the black face dial). Their calipers are made by Swiss company Etalon. While we have used these for quite some time, the price has climbed a little bit and while they are every bit as good as the Starretts, we don’t think the price increase for the improved dial visibility is justified, hence our recommendation for the Starretts. That said, the Brown and Sharpe’s are absolutely fantastic if you think the improved dial is worth the extra coin.
Like the Starretts, accuracy is +/- .001″. They are made of hardened stainless which offers the same advantages as described above for the Starretts. The Brown and Sharpe’s offer a rotating dial with locking thumb screw, a locking thumb screw for the sliding jaw, and a thumb wheel for micro adjustments. They also have a depth probe, a set of internal chamfered jaws, and a set of external chamfered jaws. They are available in a 6″ flavor as well as 8″ and 12″.
Compared to the Starrett’s they are functionally equivalent and equal in quality. You will pay a few bucks more for them but you will be just as happy (if not slightly happier due to the more legible dial if money is no object) as you would be with the Starretts.
We hope that this breakdown of the best dial calipers has guided you towards making an intelligent purchase. We want to punctuate this article by reiterating that with precision measurement tools you really do get what you pay for and in this case it does pay to spend a little bit extra for a high quality caliper. We know that you can get a caliper from Tekton, Fowler, or equivalent that may work passably for a while, but if you are in it for the long haul it makes sense to get the best. That said, while these are our favorite calipers, there are other options out there available to you if these don’t quite meet your needs. Feel free to review these options by clicking here. Happy wrenching!