Enabling better global research outcomes in soil, plant & environmental monitoring. 23
9.3
Begin Drilling
Commence drilling the three holes into the stem using a 1.3mm drill bit. Use a
cordless drill on a high RPM setting to get good clean-cutting action.
Only drill short increments on each pass (2-3mm). The moist sapwood of the
tree will build up in the flutes of the drill bit and will require cleaning.
Continuing to drill with the flutes full of fiber will burn the hole and result in
the installation site becoming unusable.
Note:
A Dremel cordless drill is recommended as it does not have a handle
with a large battery to act as a counterweight, which may cause difficulty when
attempting to drill parallel holes.
9.4
Check the Holes are Parallel
After drilling all three holes, remove the drill guide and check the installation
to see if the holes are aligned axially and parallel. This can be done by inserting
three drill bits into the holes and visually inspecting them. A piece of 5mm lined
notepaper can be a very handy guide.
Note:
You should not attempt to drill the holes quickly, the set of three holes
will take at least 10 minutes to drill correctly. If the guide slips or a drill bit
breaks (and cannot be removed without removing the guide) it is advised that
the installation be abandoned, and a new site be found to start a fresh
installation.