(5mm; 10mm; 12mm)
To avoid distorted cores, we developed a portable stage to fix the cordless drill incl. the increment corer. The drill can be started in the stage, and the rotating drill bit can be sharpened within a minute or two without problems.
To avoid micro (or even macro) cracks in your cores, you need to sharpen the drill bit frequently. This is an old issue, not really a problem when analysing increment cores macroscopically, but really problematic for cutting microsections (no matter if long or short)
Publications ¶
Gärtner H, Schneider L, Lucchinetti S, Cherubini P (2023): Advanced Workflow for Taking High-Quality Increment Cores - New Techniques and Devices. Journal of Visualized Experiments 193, e64747. doi:10.3791/64747
Sharpening procedure ¶
To sharpen a drill bit of an increment corer, you need two differently shaped, fine grinding stones.
When the corer is rotating in the sharpening stage, the first step is to place the flat stone at a 45° angle to the outside of the drill bit. Do not add too much force to the drill bit.
After doing this for a few seconds, remove the flat stone and place the cone-shaped stone parallel to the inner surface of the drill bit. Do this also for a few seconds to deburr the edge.
To test, place a sheet of paper on a wooden surface (e.g., the plate of the sharpening stage), place the increment corer vertically on the paper so that the drill bit presses down on the paper under its own weight.
Turn the corer by hand without exerting pressure to it.
Remove the corer from the paper. If a piece of paper sticks inside the drill bit, the corer is shrap. If not, repeat the sharpening process.
Recommended publications on the use and maintenance of increment corers ¶
- Reineke, L. H. (1941). A new increment core instrument and coring wrinkles. Journal of Forestry, 39(3), 304-309.
- Josza, L. (1988). Incremental core sampling techniques for high-quality cores.Rep. Special Publication SP-30. Forintek Canada Corp, Vancouver, BC.
- Grissino-Mayer, H.D. 2003. A manual and tutorial for the proper use of an increment borer. Tree-Ring Research 59(2):63-79.