Hi Mark
I have had similar problems with the goniometer…
Sorry. guys. but I’ve never used one
I believe that the problem lies in the fact that the meter requires a flat facet to reflect the laser so it points to the correct reading. In a fully convexed blade, as the edge approaches zero the job for the meter becomes more and more difficult until a point is reached near zero when the laser reflects not only from the actual edge but even more from the steel at the base of the edge.Big sprays of red laser light all over the dial.
By ‘edge approaches zero’, do you mean as the blade width approaches zero as it gets closer to the very edge?
The reading I see there is very unclear but my best guess is between 4 and 6 degrees.
On one side, but looks indeterminate on the other. Is there a chance the knife was not ‘straight’ in the V?
You might try the following…turn the knife in the slot so it rests flat on one of the V sides…take a reading of the laser at its furthest reach…do the same with the knife lying flat on the other side of the V…if the readings are the same then you are at zero or approaching zero. If there is a difference e,g, one reading is 30 degrees and the other is 35 degrees then the angle is 5 degrees.
Not following here.
Having said all that I may be full of baloney.
Don’t think so. Is there a chance that the convex edge was simulated by sharpening 1° at a time? There seems to be step-changes to the laser light at about 1° increments. Could be illusion. The right side with bigger splash might indicate that the sides are asymmetric or the knife isn’t aligned with the V. CATRA does have other models that are for thicker knives. Could be that this one is too thick for this model
I will trust that those with more scientific minds than mine will see this just that or maybe not!!
Trust no one…
