HTD-5M Timing Belt — Closed Loop Rubber Drive Belt, 20mm & 25mm Width, 175mm–3770mm

Measure the center-to-center distance between your two pulleys, then use the standard belt length formula: L = 2C + π(D+d)/2 + (D−d)²/(4C). For example, a 500mm (≈19.7") belt is typically used on compact 3D printer axes. When in doubt, size up by one increment — a slightly longer belt can be tensioned; a short one cannot be installed. You can also wrap a flexible tape measure around your existing pulley path to get the loop length directly.

HTD-5M belts are generally rated for moderate power transmission. The 5mm pitch profile handles higher torque than GT2 belts, making it suitable for CNC routers, conveyor drives, and servo-driven axes. Wider belts (25mm vs. 20mm) carry proportionally more load. For specific power ratings, consult your machine's engineering documentation or contact us to confirm suitability for your application.

These rubber timing belts are generally resistant to light moisture and dust, making them suitable for semi-protected indoor environments. Prolonged exposure to UV radiation, petroleum-based oils, or standing water can degrade the rubber compound over time. For fully outdoor installations or chemical-exposure environments, confirm material compatibility before use.

This belt requires HTD-5M pulleys — pulleys with a 5mm pitch and the rounded HTD tooth profile. It is not interchangeable with GT2 (2mm pitch), T5 (5mm trapezoidal), or MXL pulleys. Always verify your pulley is labeled HTD-5M before ordering. Using a mismatched pulley will cause tooth skipping or premature belt wear.

Belt width determines load-carrying capacity and must match your pulley's groove width. The 25mm belt carries more torque and suits heavier-duty CNC or conveyor applications. The 20mm belt is common in lighter automation, 3D printing, and laser engraver setups. Choose the width that matches your existing pulley groove — mixing widths will cause the belt to ride unevenly and wear prematurely.

This is a closed-loop (endless) timing belt — it forms a continuous loop with no seam or joint. This design provides consistent tension and eliminates the weak point found in spliced or laced belts. Installation requires sliding the belt over the pulleys before mounting the shaft or tensioner bracket. It cannot be cut and re-joined in the field.

The most reliable method is to check the markings on your existing belt — HTD-5M belts are typically marked with their pitch circumference in millimeters (e.g., "HTD 5M 500" = 500mm loop). If the belt is too worn to read, wrap a flexible tape measure or string around the full pulley path and measure the total loop length. Alternatively, check your machine's BOM or service manual for the OEM belt part number.

Yes — HTD-5M belts are commonly used on larger-format 3D printers and CO₂ laser engravers that use HTD-5M pulleys on their motion axes. However, many compact desktop 3D printers (e.g., Ender 3, Prusa MK series) use GT2 belts, not HTD-5M. Verify your machine's pulley type before ordering. If your pulleys are labeled HTD-5M, this belt is generally a direct fit.