Low-pressure Dial IndicatorsChecking Fixtures Design, Quality Control — By Xavier Conesa on 23 December 2010 at 7:46 pm
To measure parts or elements made of soft materials, it is necessary to use low-pressure dial indicators. Most of these dial indicators, for all the brands available on the market, work with a force of 1.5 to 2N. This force can be reduced if we use a flat probe instead of a round probe, if the geometry of the part enables it.
If this solution is not enough, you can also use the Mitutoyo 543-349B line of products (value display of thousandths of millimeters) that work with a force ranging from 0,4 to 0,7N, or the Mitutoyo 543-404B line of products (value display of hundredth of millimeters) that work with a force between 0,2 and 0,5N. Their price is higher, but they may solve your problem.
If you need to work with lower pressures, you can use Marposs type spring or pneumatic measurement probes, that can work with forces as low as 0.15N.