Many of you are familiar with Mahr for their roundness gages and surface finish roughness gages. However, did you know that they also have a couple of product lines that excel in camshaft measurement? Mahr’s MarForm MMQ 400 and MFU 100 have used tactile probes to provide camshaft profile measurement for years.
These machines are used for audit measurements in automotive factories around the world. Combining a roundness gage with a tailstock to support the part and self-center the workpiece, the MMQ provides a very flexible shaft measurement solution. Years of development work have helped them to prove out their profile algorithms to the point that the measurement results agree with camshaft measuring machines from many other manufacturers. However, there is another product produced by Mahr that really impresses me, the MarShaft Scope Plus series. In particular, the 600 plus 3D variant. The MarShaft Scope Plus series combines the best of non-contact optical measurement, with a tactile probe option, for what I think is one of the most flexible shaft gauges on the market, but is particularly well suited to customers that measure camshaft profiles, along with other rotating parts.
Optical gages using telecentric lenses and a CCD array have been used for years to measure cylindrical parts. On camshafts, they very fast. Capable of measuring diameters, phase angles and profile (so long as there is not a negative radius on the flanks of the cam lobe), an optical gage can be the sole solution for certain camshaft types . But for many modern camshaft profiles with a negative radius, or to measure surface undulations and roundness, a tactile (contact) probe is needed. This is where the MarShaft Scope Plus excels, at it COMBINES the speed of an optical non-contact gage with the accuracy of a tactile probe. The tactile probe can measure circumferential features, but can also measure axial features (z-axis, or “along the length of the part”). This makes it particularly well suited for measurement of sliding camshafts, which vary valve lift by using a channel to “slide” the camshaft axially. You can watch a number of videos about this technology, which is currently used by Daimler, Audi, and other OEMs, on YouTube. Here is an example of one such shaft, which shows the channel feature in detail, on an Audi product:
Maybe you also need a fully automatic camshaft measuring machine for your production cell or line. The MarShaft Scope Plus (the 750 here is pictured) can be robot loaded and when configured this way, uses very little shop floor space.
Or, maybe you’d like to have a set-up gage out on the floor, close to the grinders. The MarShaft Scope can use its precision telecentric lenses and CCD system to provide FAST results for phase angle, sizes, and available grind stock. When you are done grinding the camshaft, the SAME machine can provide profile results for the audit check. Providing a set up gage at the grinder is a common practice, especially in larger facilities where the equipment cost is reduced through labor savings. Keeping the operator at the machine, rather than crossing the floor to an inspection room, is a smart way to improve efficiency.
Another advantage of the MarShaft Scope Plus is that it is not a dedicated camshaft gauge. It is also capable of measuring other parts like transmission shafts and pistons. This adaptability means you can run multiple engine part applications on the same machine, saving money in gauging. For audit inspection in an engine factory, or incoming inspection at an engine build shop, there are very few machines that provide so much value for the money.
More about the MarShaft camshaft gage applications can be found on the Mahr site, here. Use the menus to find details: applications>automotive>engineparts>camshafts
The final feature that impresses me about the MarShaft series is their software, referred to as the MarWin EasyShaft product.
The MarWin software uses pictogram style prompts to guide the operator and is one of the most intuitive UIs in the gauging industry. I was able to understand it in a few minutes and was programming a shaft in under an hour. This translates to real cost saving if you have to set up multiple part types. You can watch a quick video which shows one of the features of MarWin EasyShaft, here.
If you have an interest in this product, I suggest that you contact Mahr directly, as I have no affiliation with the company. Mahr contact information is located here.
It is worth noting that Jenoptik offers a similar solution in their Hommel-Etamic Opticline C-series.
Although I have less exposure to this system, I’ve found that Jenoptik makes quality measurement systems with intuitive software. You can contact Jenoptik directly, here, or view their video, below.
Please stay tuned as I explore other interesting technologies and solutions in the coming months!
*Note: This author is not affiliated with Mahr or Jenoptik and receives no compensation for these articles. I’m just a camshaft and crankshaft metrology geek, that appreciates good product and software!