BigTreeTech's Belter Puts a Digital Number on 3D Printer Belt Tension

The Right Tension Makes the Difference

Loose belts cause ghosting. Over-tight belts wear bearings and add drag. Most of us solve this by plucking the belt like a guitar string and hoping for the best. BigTreeTech thinks there is a better way, and the BIQU Belter is its answer.

The Belter is a small digital gauge that clamps onto a GT2 belt and returns a reading you can convert to Newtons. It is not the first tension meter aimed at 3D printer builders, but it is one of the most purpose-built. The body is a lightweight sandblasted aluminum bracket, the sensor is electronic, and the readout is a simple digital screen. A single CR2032 powers it.

How It Works

According to the project repository and product page, you print a small probe part, zero the unit against the belt, then take a reading. BigTreeTech provides a calculation table that turns the raw value into belt tension. The idea is to hit the same number on every axis, not just the same pluck pitch.

That repeatability matters. On a CoreXY machine like a Voron 2.4 or VZBOT, uneven belt tension can show up as skewed corners or inconsistent layer stacking. On a Cartesian printer, a loose X belt turns circles into ovals. The Belter gives you a way to document your setup and return to it after maintenance.

Compatibility and Price

The tool is aimed at GT2 belts, which covers most Voron, RatRig, Ender and similar machines. It is listed on the BIQU store and ships with the printed probe parts and a calculator sheet. At around the price of a few spools of filament, it sits firmly in the enthusiast tool category rather than the pro metrology lab.

Is it essential? No. A free phone app and a careful ear can get you close. But for builders who like data, or anyone chasing ringing and ghosting on a high-speed CoreXY rig, a real number is worth the bench space.