20 : 30 · 1 : 1.5
T5 20T & 30T, 16 mm Wide Belt
More belt for more load: a 16 mm T5 belt with the face widened to suit, on D-flat shafts with an M4 set screw in each hub.
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.
Build it with your AI
Using the CheapCAD Tools connector, design a two-pulley timing belt drive: AT5 belt, about 140 mm between centres, M4 set screws in heat-set inserts on both hubs. Pulley 1: 24 teeth, 8 mm bore, a hub 22 mm across and 9 mm tall. Pulley 2: 36 teeth, 10 mm bore, a hub 24 mm across and 9 mm tall, 5 spokes around a 24 mm spoke hub with a 5 mm rim under the teeth, and printed flanges whose top flange is a separate part held on by 12 gluing nubs. Check the design, apply any Auto-fix it suggests, then export both pulleys as STL and give me the download link.
Paste it into Claude, ChatGPT or any AI app with the CheapCAD Tools connector, and it designs this drive with you, checks it and hands you the files. How to connect your AI.
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, under a 5 mm deep rim
- Printed flanges, 1.5 mm thick, reaching 3 mm past the teeth; the top flange prints separately and locates on 12 alignment nubs
In the free STL zip
AT-AT5-24T.stl— pulley 1, 24 teethAT-AT5-36T-P2+flange.stl— pulley 2, 36 teethATAT5-36T-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 — 15 figures from the generator
| Pulley 1 | Pulley 2 | |
|---|---|---|
| Pitch diameter | 38.20 mm | 57.30 mm |
| Outside diameter | 37.00 mm | 56.10 mm |
| Root diameter | 34.80 mm | 53.90 mm |
| Groove depth | 1.10 mm | 1.10 mm |
| Pitch line differential | 0.60 mm | 0.60 mm |
| Belt width | 10.00 mm | 10.00 mm |
| Face width (belt + clearance) | 10.50 mm | 10.50 mm |
| Flange outside diameter | — | 62.10 mm |
| Flange past the OD | — | 3.00 mm |
| Minimum flange height | — | 1.70 mm≈ |
| Flange inward of the groove | — | 5.00 mm |
| Minimum flange overlap | — | 3.00 mm≈ |
| Belt | 87 teeth · 435.00 mm | |
| Centre distance | 142.18 mm | |
| Drive ratio | 24 : 36 · 1 : 1.5 | |
Read from the generator's Dimensions panel for this design, which opens with no warnings.
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20 : 30 · 1 : 1.5
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HTD 5M 20T & 30T, ISO Keyways & Metal Flanges
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