30 : 45 · 1 : 1.5
STD S3M 30T & 45T, Custom Tooth Fit
When the presets aren't quite right for your printer: tooth clearance and backlash dialled in by hand, on the round-toothed STD S-series profile.
Sample · Timing Pulley Generator
RPP 5M pulleys with an open three-spoke web
RPP's parabolic teeth around an open three-spoke web, with generous fillets at both ends of every spoke.
What's in this design
The drive
- RPP 5M belt, 10 mm wide, 86 teeth (430 mm long)
- Centre distance 152.29 mm; ratio 20 : 30 (1 : 1.5)
Pulley 1
- 20 teeth
- 8 mm round bore
- Hub Ø20 × 8 mm, two M4 set screws tapped into the plastic
Pulley 2
- 30 teeth
- 10 mm round bore
- Hub Ø22 × 8 mm, two M4 set screws tapped into the plastic
- 3 spokes, 6 mm wide, with 3 mm and 4 mm fillets
- Printed flanges, 1.5 mm thick, reaching 4.8 mm past the teeth; both print in place, the top one on breakaway supports for a 0.4 mm nozzle
In the free STL zip
RPP-5M-20T.stl— pulley 1, 20 teethRPP-5M-30T-P2+flange.stl— pulley 2, 30 teeth, without supportsRPP5M-30T-Assembly.stl— pulley 2 with both flanges and breakaway supports: print this one
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 — 14 figures from the generator
| Pulley 1 | Pulley 2 | |
|---|---|---|
| Pitch diameter | 31.83 mm | 47.75 mm |
| Outside diameter | 30.69 mm | 46.61 mm |
| Root diameter | 26.57 mm | 42.49 mm |
| Groove depth | 2.06 mm | 2.06 mm |
| Pitch line differential | 0.57 mm | 0.57 mm |
| Belt width | 10.00 mm | 10.00 mm |
| Face width (belt + clearance) | 16.00 mm | 16.00 mm |
| Minimum face width | 16.00 mm | 12.00 mm |
| Flange outside diameter | — | 52.09 mm |
| Flange past the OD | — | 2.74 mm |
| Minimum flange height | — | 2.72 mm |
| Belt | 86 teeth · 430.00 mm | |
| Centre distance | 152.29 mm | |
| Drive ratio | 20 : 30 · 1 : 1.5 | |
Read from the generator's Dimensions panel for this design, which opens with no warnings.
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