Step 07.31 — Read both belts with the phone¶
Step 31 of 39 with a helper · Chapter 07 — A/B belts and tensioning
Parts: none.
Do:
- Start the spectrum app, hold the phone close to the belt, and pluck the free 150 mm section like a guitar string.
- Read the lowest frequency peak, not the loudest and not a harmonic. Do both belts.
Check
Three plucks in a row land within a few Hz of each other. A reading that jumps around is a harmonic or room noise.
Helper Holds the phone by the belt and reads the lowest peak aloud after each pluck.
What you're looking at
The spectrum app turns a plucked belt into a plot of frequency against level. The number you want is the lowest peak, the fundamental. A belt also rings at two and three times that, and a harmonic reads as twice the real tension.
Source: Voron docs § Secondary printer tuning — A/B Belts · image sound-spectrum-belt.jpg
