PiCUS TreeQinetic Manual
15
Montage
To attach an elastometer to the tree, you need a pair of elastometer needles, the needle gauge
and a hammer.
The needles are inserted into the gauge so that the tips point away from the handle and
towards the tree. The gauge is placed where the elastometer is to be attached. Then the
needles are driven in at the distance given by the gauge. The needles must be firmly attached
to the actual wood (xylem) to ensure that the fibre length change is transmitted to the gauge.
The gauge is carefully pulled off.
CAUTION!
The needles must not be driven in any further as long as the sensitive elastometer is connected
to them!
The locked elastometer is placed on the lower needle with the lower needle bracket and initially
held slightly tilted to the right. The bottom of the display points to the tree. A slight tilting
movement brings the upper needle bracket up to the upper needle. If the distance between the
needles is correct, the bracket will hit exactly. The elastometer is positioned so that it comes
as close as possible to the tree without the instrument touching the tree.
The lower and upper knurled screws are tightened by hand and fix the gauge in place. After
tightening, the lock can be released. This should be possible without strong resistance or
tension.
The first measured value of the elastometer (before zeroing) should be in the range of a few
hundred µm at most. If the value is above 1000 µm, the device has not been attached with
sufficient precision.
To pull out the needles without damaging them the rivet pliers should be used (3.1 mm).
Figure 4
– Attaching the elastometer
