Overview
What are timing pulley blanks?
A timing pulley blank is a pre-manufactured disc with the tooth profile already cut to standard, but without final bore machining. The bore is left smaller than required (L1 = primary bore diameter) and is subsequently machined to the customer's exact shaft diameter, keyway, flange or Taper Bush seat.
Blanks are the economical solution when: a non-standard bore diameter is required; the pulley must be mounted with a key, pin or press fit; the customer has machining capacity for final bore work. Profiles: MXL (2.032 mm), XL (5.08 mm), L (9.525 mm), AT5 (5 mm), AT10 (10 mm).
Blank dimensions
Columns: Code | Teeth | de = outside diameter (mm) | L1 = bore zone length (mm) | L = total length/thickness (mm) | Kg
Profiles and dimensions
MXL blanks (pitch 2.032 mm) — Aluminium
Profile MXL, pitch 2.032 mm, aluminium:
| Code | Teeth | de (mm) | L1 (mm) | L (mm) | Kg |
|---|---|---|---|---|---|
| MXL 45 | 45 | 28.60 | 140 | 140 | 0.24 |
| MXL 48 | 48 | 30.54 | 140 | 140 | 0.27 |
| MXL 50 | 50 | 31.83 | 140 | 140 | 0.30 |
| MXL 60 | 60 | 38.30 | 160 | 160 | 0.49 |
| MXL 70 | 70 | 44.77 | 160 | 160 | 0.67 |
| MXL 72 | 72 | 46.06 | 160 | 160 | 0.72 |
XL blanks (pitch 5.08 mm) — Aluminium
Profile XL, pitch 5.08 mm, aluminium:
| Code | Teeth | de (mm) | L1 (mm) | L (mm) | Kg |
|---|---|---|---|---|---|
| XL 29 | 29 | 46.39 | 160 | 160 | 0.70 |
| XL 30 | 30 | 48.00 | 160 | 160 | 0.75 |
| XL 32 | 32 | 51.24 | 160 | 160 | 0.87 |
| XL 36 | 36 | 57.70 | 160 | 160 | 1.10 |
| XL 40 | 40 | 64.17 | 160 | 160 | 1.37 |
| XL 44 | 44 | 70.64 | 160 | 160 | 1.65 |
| XL 48 | 48 | 77.11 | 160 | 160 | 1.98 |
| XL 56 | 56 | 90.04 | 160 | 160 | 2.71 |
| XL 60 | 60 | 96.51 | 160 | 160 | 3.10 |
| XL 72 | 72 | 115.92 | 160 | 160 | 4.52 |
L blanks (pitch 9.525 mm) — Steel
Profile L, pitch 9.525 mm, steel:
| Code | Teeth | de (mm) | L1 (mm) | L (mm) | Kg |
|---|---|---|---|---|---|
| L 10 | 10 | 29.56 | 140 | 140 | 0.66 |
| L 12 | 12 | 35.62 | 160 | 160 | 1.12 |
| L 14 | 14 | 41.68 | 160 | 160 | 1.57 |
| L 16 | 16 | 47.75 | 160 | 160 | 2.08 |
| L 18 | 18 | 53.81 | 160 | 160 | 2.64 |
| L 20 | 20 | 59.88 | 160 | 160 | 3.32 |
| L 22 | 22 | 65.94 | 160 | 160 | 4.07 |
| L 24 | 24 | 72.00 | 160 | 160 | 4.86 |
| L 27 | 27 | 81.10 | 160 | 160 | 6.20 |
| L 30 | 30 | 90.20 | 160 | 160 | 7.72 |
AT5 blanks (pitch 5 mm) — Aluminium
Profile AT5, pitch 5 mm, aluminium:
| Code | Teeth | de (mm) | L1 (mm) | L (mm) | Kg |
|---|---|---|---|---|---|
| AT 5 12 | 12 | 17.85 | 140 | 140 | 0.08 |
| AT 5 15 | 15 | 22.65 | 140 | 140 | 0.14 |
| AT 5 18 | 18 | 27.40 | 140 | 140 | 0.20 |
| AT 5 20 | 20 | 30.60 | 160 | 160 | 0.30 |
| AT 5 24 | 24 | 37.00 | 160 | 160 | 0.44 |
| AT 5 28 | 28 | 43.35 | 160 | 160 | 0.60 |
| AT 5 32 | 32 | 49.70 | 160 | 160 | 0.81 |
| AT 5 36 | 36 | 56.05 | 160 | 160 | 1.02 |
| AT 5 40 | 40 | 62.45 | 160 | 160 | 1.28 |
| AT 5 48 | 48 | 75.15 | 160 | 160 | 1.85 |
| AT 5 56 | 56 | 87.90 | 160 | 160 | 2.55 |
| AT 5 64 | 64 | 100.65 | 160 | 160 | 3.36 |
AT10 blanks (pitch 10 mm) — Aluminium
Profile AT10, pitch 10 mm, aluminium:
| Code | Teeth | de (mm) | L1 (mm) | L (mm) | Kg |
|---|---|---|---|---|---|
| AT 10 15 | 15 | 45.90 | 160 | 160 | 0.62 |
| AT 10 18 | 18 | 55.45 | 160 | 160 | 0.94 |
| AT 10 20 | 20 | 61.80 | 160 | 160 | 1.17 |
| AT 10 24 | 24 | 74.55 | 160 | 160 | 1.75 |
| AT 10 28 | 28 | 87.25 | 160 | 160 | 2.42 |
| AT 10 32 | 32 | 100.00 | 160 | 160 | 3.20 |
| AT 10 36 | 36 | 112.75 | 160 | 160 | 4.09 |
| AT 10 40 | 40 | 125.45 | 160 | 160 | 5.16 |
| AT 10 48 | 48 | 150.95 | 160 | 160 | 7.45 |
| AT 10 56 | 56 | 176.40 | 160 | 160 | 10.39 |
| AT 10 60 | 60 | 189.15 | 160 | 160 | 11.78 |
| AT 10 70 | 70 | 220.95 | 160 | 160 | 16.18 |
Timing pulley blanks
Download PDF ↓Frequently Asked Questions
What is the difference between a blank and a pilot bore pulley?
A pilot bore pulley is supplied with a pre-drilled standard bore ready for final machining. A blank is a complete disc without central bore — the customer specifies bore size, position and type (cylindrical, keyway, eccentric, etc.).
Who are blanks suitable for?
Engineering companies and service workshops with turning/milling capacity, for non-standard constructions or special mounting requirements (key, interference fit, flange).
Which profiles are available?
MXL (2.032 mm pitch, Al), XL (5.08 mm, Al), L (9.525 mm, St), AT5 (5 mm, Al), AT10 (10 mm, Al). For other profiles — enquire at nibora@nibora.com.
What does L1 mean?
L1 is the length of the bore machining zone — the uninterrupted hub zone without teeth, in the central hub area. L is the total depth/thickness of the pulley.