How to read? Gates Krikit II V-Belt Tension Gauge

Can someone remind me how to read this device?


which side of the triangle is the right side to read?

Re: Gates Krikit II V-Belt Tension Gauge

left side in pix

Any way to tighten up the swing arm without damaging the tool? I see a little spring under it, but it looks like friction is what is supposed to hold the arm in place after it clicks. I used mine for one belt install and the swing arm is already loose. It just falls back into the tool as I remove it from the belt. Makes reading it kind of a hassle as I have to read it while attempting to apply steady pressure to the tool/belt.

It is just friction that keeps the arm stiff. I would try to apply pressure to where the arm mounts.

I'd take it back. Ive used mine about 20 times and it is still tight.