The price for professional Treehouse Screws seems high at first, which always leads to the question whether you can simply manufacture the Treehouse Screws yourself? Here is my assessment (after countless series of tests and years of professional experience as a treehouse builder):
Tree Screws are highly stressed components (often several tons of load). The load situation is dynamic, i.e. the tree-bolt connection is permanently exposed to alternating loads (gales, wind fluctuations, crowds, snow load).
Treehouses are usually installed several metres above the ground, a material defect can have fatal consequences.
In the course of numerous bachelor theses, we ourselves did a lot of research on the screw geometry, the materials and the manufacturing process: during our experiments, some prototypes broke off (see pictures); the failure was caused by wrongly placed welding seams, the wrong welding process, unsuitable types of steel, uncleanly executed thread transitions, … all our prototypes looked perfect from the outside!
I wouldn’t have thought it either, but there is a lot of know-how behind the professional treehouse bolts (e.g. Garnier Limb GL or Treehouse Attachment Bolt TAB from the USA)!
Here are a few sample pictures from our field tests:
|Material Failure Treehouse Screw||Material Failure Treehouse Screw
||Load Test Treehouse Screws
||Prototypes Treehouse Bolt|
So, now you can decide for yourself …
We won’t give you detailed instructions or tutorials, but here’s my tip if you want to build a “tree screw” yourself: get an experienced locksmith / trained metalworker who is familiar with steel alloys! Use our dimensions as a guide, pay attention to thread transitions, undercuts, and clean welds in the critical area (0 – 8 cm inside the tree, max. load on shear and max. torque). If possible, make the screws from a single cast or with precision pressing.