BONNETHEAD
Compact Performance Variant
Description
The Bonnethead is a compact version of the Hammerhead platform that preserves full plunger geometry and output in a shorter frame. Using a 3"+3" paired spacer and a 4" spacer, the overall length is reduced while maintaining rigidity and alignment. The design keeps the same power profile and reliability as the full-size platform in a lighter, more maneuverable format. Unique Turn Around and Slide components define its compact operation and layout.
Hardware Kit (Bonnethead / Scoophead)
| Part | McMaster # | Qty required |
|---|---|---|
| 4-40 3/8" FH (steel) | 90273A108 | 24 |
| 4-40 1" FH (steel) | 90273A115 | 12 |
| 10-32 3/4" FH (steel) | 90273A831 | 6 |
| 10-32 1.25" BH (steel) | 91440A516 | 6 |
| 10-32 1.75" BH | 90279A837 | 6 |
| 10-32 1/8" thick nut | 90480A195 | 12 |
| 10-32 Flange nut | 90389A113 | 3 |
| 10-32 threaded rod (3ft) | 98838A011 | 30 |
| Catch Washer | 7421K12 | 1 |
| 1.5" OD washer | 92141A035 | 1 |
| 4" Spacer (steel) | 93265A042 | 1 |
| 3" Spacer (steel) | 93265A034 | 4 |
| 1" Spacer | 93330A476 | 3 |
| Small Spring (3/4") (36" ×5) | 9662K16 | 6 |
| K26 (11") (5.5" piece) | 9637K26 | 1 |
| K25 (11") (5.5" piece) | 9637K25 | 1 |
| 1.375" ID Plunger Tube (3ft) | 53945K21 | 5 |
| Alum tube 0.509" ID (3ft) | 9390N15 | 7 |
| Press Insert for plastic | 92395A112 | 6 |
| 1.375" OD O-RING | 9452K87 | 6 |
| 0.5" OD O-RING FAT | 9452K18 | 6 |
| 0.5" OD O-RING | 9452K21 | 6 |
Key Features
-
Compact frame with identical plunger geometry and power output
-
Spacer layout uses paired 3" + 3" and 4" segments for reduced length
-
Requires spacer matching to achieve a consistent 6" smooth segment
-
Includes Turn Around and Slide components unique to this variant
-
Suitable for builders wanting a shorter platform without performance loss
Spacer Note
Dual 3" spacers must be tolerance matched to form a true 6" smooth segment. Buying 6" spacers is an option but at higher cost. Expect some surplus if pairing your own.