Sample · Timing Pulley Generator

AT5 pulleys with set screws in heat-set inserts

For a linear axis that gets adjusted often: AT5's stiff belt, with M4 set screws running in heat-set inserts so the threads survive, and a spoked 36-tooth pulley.

AT5Heat-set insertSpokesAlignment nubs

What's in this design

The drive

  • AT5 belt, 10 mm wide, 87 teeth (435 mm long)
  • Centre distance 142.18 mm; ratio 24 : 36 (1 : 1.5)

Pulley 1

  • 24 teeth
  • 8 mm round bore
  • Hub Ø22 × 9 mm, two M4 set screws in heat-set inserts

Pulley 2

  • 36 teeth
  • 10 mm round bore
  • Hub Ø24 × 9 mm, two M4 set screws in heat-set inserts
  • 5 spokes, 4 mm wide
  • Printed flanges, 1.5 mm thick, reaching 3 mm past the teeth; the top flange prints separately and locates on 4 alignment nubs

In the free STL zip

  • AT-AT5-24T.stl — pulley 1, 24 teeth
  • AT-AT5-36T-P2+flange.stl — pulley 2, 36 teeth
  • ATAT5-36T-3DP-upper-flange.stl — pulley 2's top flange, printed on its own

Free STLs are CC BY 4.0, printed size without print compensation. Open the design to change anything, tune the fit for your printer, or download STEP, DXF, SVG and the belt.

Dimensions — 13 figures from the generator
Pulley 1Pulley 2
Pitch diameter38.20 mm57.30 mm
Outside diameter37.00 mm56.10 mm
Root diameter34.80 mm53.90 mm
Groove depth1.10 mm1.10 mm
Pitch line differential0.60 mm0.60 mm
Belt width10.00 mm10.00 mm
Face width (belt + clearance)10.50 mm10.50 mm
Flange outside diameter—59.90 mm
Flange past the OD—1.90 mm
Minimum flange height—1.70 mm≈
Belt87 teeth · 435.00 mm
Centre distance142.18 mm
Drive ratio24 : 36 · 1 : 1.5

Read from the generator's Dimensions panel for this design, which opens with no warnings.

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Opening the tool…
The first load can take a few seconds.