Xem Studiomeasured geometryGT2 timing pulleys, 16T–60T (2 mm pitch)
What is the outer diameter of a GT2 20 tooth pulley? · Hardware · basis: GT2 (2 mm pitch) geometry: pitch diameter = teeth × 2 / π, OD = PD − 0.508 mm; flange and hub sizes typical of printer-kit aluminium pulleys
- sizes
- 7 in table
Notes
- Pitch diameter sets the motion: 20T = 12.73 mm PD, so one motor turn moves the belt 40 mm. OD is 0.508 mm less than PD.
- Common bores 5 mm (NEMA 17) and 8 mm (idler shafts). Belt widths 6 mm (standard) and 10 mm (heavier axes).
- Tooth profile in these files is an approximation for fit and clearance, not a belt-grade profile; buy the aluminium pulley for the drive.
Sizes
| teeth | pitch_dia_mm | od_mm | flange_dia_mm | belt_mm | bore_mm |
|---|---|---|---|---|---|
| 16 | 10.19 | 9.68 | 12.7 | 6 | 5 |
| 20 | 12.73 | 12.22 | 15.2 | 6 | 5 |
| 20 | 12.73 | 12.22 | 15.2 | 6 | 8 |
| 36 | 22.92 | 22.41 | 25.4 | 6 | 5 |
| 40 | 25.46 | 24.96 | 28.0 | 6 | 5 |
| 60 | 38.2 | 37.69 | 40.7 | 6 | 8 |
| 20 | 12.73 | 12.22 | 15.2 | 10 | 5 |
Where the files are
Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.
| Wikipedia | Timing belt (camshaft) | web | CC BY-SA 4.0 (text) |
| Gates | PowerGrip GT2 belt and pulley design guide | Gates site terms verify |
Free files
★ Free files 7 parts. Generated by Xem Studio from the standard; threads are plain cylinders at major diameter. CC BY 4.0. index.json
| gt2-16t-5 | GT2 16T, bore 5, 6 mm belt; approximate tooth profile, two M3 set screws | STEP · STL |
| gt2-20t-5 | GT2 20T, bore 5, 6 mm belt; approximate tooth profile, two M3 set screws | STEP · STL |
| gt2-20t-8 | GT2 20T, bore 8, 6 mm belt; approximate tooth profile, two M3 set screws | STEP · STL |
| gt2-36t-5 | GT2 36T, bore 5, 6 mm belt; approximate tooth profile, two M3 set screws | STEP · STL |
| gt2-40t-5 | GT2 40T, bore 5, 6 mm belt; approximate tooth profile, two M3 set screws | STEP · STL |
| gt2-60t-8 | GT2 60T, bore 8, 6 mm belt; approximate tooth profile, two M3 set screws | STEP · STL |
| gt2-20t-5-w10 | GT2 20T, bore 5, 10 mm belt; approximate tooth profile, two M3 set screws | STEP · STL |
Plain text: sheet.txt · JSON: /api/geometry?object=gt2-pulleys
Fits with
Questions
What is the diameter of a 20 tooth GT2 pulley?
Pitch diameter 12.73 mm, outer diameter 12.22 mm, flanges about 16 mm. One revolution moves the belt 40 mm.
What is the diameter of a 16 tooth GT2 pulley?
Pitch diameter 10.19 mm, OD 9.68 mm; 32 mm of belt per revolution.
How far does a GT2 belt move per step?
With a 20T pulley on a 200-step motor at 16× microstepping: 40 mm / 3200 = 0.0125 mm per microstep (80 steps/mm).
What size is a GT2 idler?
Toothed idlers are 16T or 20T on a 3 mm or 5 mm bore bearing; smooth idlers are Ø16–18 mm. A 623 bearing stack (3×10×4) is the common DIY idler.