How Much Does a Roughness Gauge Cost?
How Much Does A Portable Surface Roughness Tester Cost?
A question asked by every customer interested in measuring surface roughness is How Much Does A Portable Surface Roughness Tester Cost? Roughness gauges are relatively inexpensive and the answer will vary depending on the functionality of the tester, but the short answer is between $800 to $5,000 dollars. The long answer will depend on the roughness parameters (Ra, Rz, Rq, etc) the tester can conduct and the accessories to adapt to part and shop floor requirements.
Portable surface roughness gauges are produced for two main subgroups: a pocket-sized instrument with a built-in stylus and an advanced portable instrument with exchangeable styluses capable of measuring multiple surface finish parameters. In either case, Portable Surface Roughness Testers were developed to conduct quick spot checks either in hard to reach locations or when it is not conducive to take the part to be tested to a workbench.
There are also tabletop, larger stylus profilometers, and non-contact profilometry instruments for advanced research. For this article, those instruments are not included in this conversation.
So how do you determine which subgroup you need?
It is quite simple. First, start with a list of the application information such as: measurement parameter, how much space is around the test location and curvature of the test site. Second, compare requirements to the specifications of the instruments.
List of Application Information and subgroup Limitations
Each requirement for a sample can be different. List out what is needed. The three main questions are: What surface roughness parameters do you require? How much space is around the test surface? and What is the shape of the test location? The more advance features a roughness gauge has, the more it will cost.
What roughness parameters will the test require?
Each instrument has on-board computing to calculate different parameters from Average Roughness (Ra), Rq (root mean squared roughness), Rz (peak roughness) to more obscure measurements parameters such as (Rku) Sharpness of profile peaks. Determining which surface finish parameter you will need will easily place your work into one of the two subgroups.
The pocket-sized instruments with a built-in stylus usually can handle 2 and sometimes 4 of the most commonly used parameters, Ra, Rz, Rq(RMS), and Rt.
The more advanced instruments with exchangeable styluses can measure a wider range of roughness parameters such as: Ra, Rz, Rq(RMS), Rt, Rp, Rv, R3y, RzJIS, Rsk, Rku, Rsm, Rmr.
After determining the parameters, it is time to determine the space requirements.
How much space is around the surface test location?
The sample length for portable roughness testers is quite small, typically limited to a 2.5mm sample length and a total tracing length less than 10mm. Determine the amount of clearance area around the test location. Is there more than 3 inches or clear space around the test location, or less than 3 inches of clear space? Also, is there more than 6 inches or height space above the test location?
The pocket-sized instruments with a built in stylus work by placing the entire instrument onto the surface of the test piece. With this instrument you will need at 3 inches of clear space around and 6 inches of clear space above the test location on average.
The more advanced instruments with exchangeable styluses work by extending the stylus and measurement tip out from the instrument. These instruments allow for measurements in more confined spaces.
What is the shape of the test location?
Test pieces come in all shapes and sizes. Determining what the shape and size is will be the final factor into which subgroup your testing will require. It can be matched to the limitations of the separate subgroups.
The pocket-sized instruments with a built in stylus require that the instrument sit on the test piece at the test location. They need ample room and work with flat or convex surfaces. On concave surfaces, the diamond tip of the stylus will not be able to reach the surface to be tested, as the stylus is built-in and flat with the bottom of the tester.
The more advanced instruments have the stylus that extends from the instrument. Along with different styluses, this model can reach into concave test areas, bored holes, and o-ring groves.
So for large flat or slightly convex surfaces you can utilize the pocket roughness gauges. For more complex surfaces and harder to reach areas, it is best to go with a more advanced roughness gauge.
After determining what subgroup of instrument you need there are some small factors that can play a large roll in the decision process of which brand to buy.
Do you need software and the ability to transfer and store data? Different gauges over different options for data storage and transfer to computers via USB or serial communications.
Warranties and support should also be considered.
So How Much Does A Roughness Gauge Cost?
For routine surface finish measurements in the field on flat and slightly convex surfaces, a simple roughness gauge with the profiling stylus built into the device can be utilize. These gauges display the data on the screen and in some instances store several roughness measurements. This will cost you on the order of $900.
For more advanced field work, with more roughness parameters measured, a more complex but still portable roughness tester is need. This allows you more flexibility to measure different types of surface shapes and to transfer the data to a computer via a USB interface. For a surface finish gauge on this order expect to pay $1,300 or more.
For more information on portable roughness testers, contact Ian at firstname.lastname@example.org or (484) 274-9341. If you would like to purchase a roughness tester, Ian can assist you so select the best option for your needs, or you can purchase directly from our on-line store.