July 30, 2024

the DataMate records both A and B axes with only two passes through the casing: the A0 and A180 pass. The B axis is less accurate because the wheels can move from side to side in the A grooves, and this affects the tilt of the sensor in the B axis. Slope Indicator’s casing has very narrow grooves, so this is not usually a problem. However, if you are using casing that has wider grooves, the probe can wander in the B axis and give less accurate readings. In that case, the highest accuracy is obtained by orienting the probe so that the wheels travel in the B axis. (Thus you use the A-axis accelerometer to record B axis readings).

The DataMate offers a “Uniaxial” routine that lets you record one direction at a time: A0, A180, B0, and B180. When you step through the parameters of the borehole before recording a survey, change Type from Digitilt to “Spiral.” This tells the DataMate to perform a uniaxial survey. Keep your instrument constant, depths, and intervals the same as usual. The DataMate will then prompt for the A0 pass, continue with the A180 pass, and continue with the B0 and B180 grooves.

When you retrieve the data with DMM, you have to make one change. In the dataset header of DOS DMM, change the value of “Spiral?” to N or False. In the Windows DMM, change the value of Probe Type from Spiral to Digitilt.