TECHNICAL ARTICLES
Crankshaft Thread Size Chart
The following chart has been provided with the assistance by the fine people at Du-Bro. Du-Bro has been providing the model industry with literally hundreds of products for over 40 years and have been one of the mainstays of the industry.
This chart should be helpful when selecting spinners, spinner adapter nuts and hub nuts for your aircraft.
| Manufacturer | Engine Designation | Thread Size |
|---|---|---|
| ASP | .21 ABC - .46 ABC | 1/4" - 28 |
| ASP | .61 all models, .75 ABC, .91 ABC, .65 4-C, .80 4-C |
5/16" - 24 |
| Enya | SS.25, SS.25BB, SS.30, SS.30BB, .35X, SS.40, SS40BB, SS.45 Ring, .46 4-C, .41 4-C | 1/4" - 28 |
| Enya | .15, SS.15, .19, .19X, .21CX, .25X | 6.0 x 1mm |
| Enya | .35, .40, .40X, .40CX, .49X, .45, .45CX, GP.45CX, .50CX, .60FXIII, GP-60XF-4, GP.60XF-4H, .60XLF, GP.60XLF-4, .60 4-C, .80 4-C, .90 4-C, 120 4-C | 7.0 x 1mm |
| Enya | R120 4-C, R120GP 4-C | 8.0 x 1mm |
| Fox | .19RC, .19CL, .25RC, .25CL, .35CL, .40RC, .40CL, .50RCBB, .45RC Schnuerle, .40 Quickie | 1/4" - 28 |
| Fox | .60 - .74 Eagle | 5/16" - 24 |
| Fitzpatrick | .61 ABC | 1/4" - 28 |
| HB | .20 - .61 all models | 1/4" - 28 |
| HP | .21 - .61 all models | 1/4" - 28 |
| HP | VT.21 4-C, VT.49 4-C, .40FRT Gold Cup, .61FRT Gold Cup |
6.0 x 1mm |
| HP | 1.20 | 5/16" - 24 |
| Irvine | .20 - .61 all models | 1/4" - 28 |
| K&B | .20 - .65 all models | 1/4" - 28 |
| Magnum | GP.25, GP.40, Pro.25, Pro.36SE, Pro.40SE, Pro.46SE | 1/4" - 28 |
| Magnum | GP65SE, Pro.61SE | 5/16" - 24 |
| MDS | .46 | 1/4" - 28 |
| MDS | .25 - .40 | 6.0 x 1mm |
| MDS | .61 | 5/16" - 24 |
| Merco | .33 - .40 | 1/4" - 28 |
| Merco | .50, .61 | 5/16" - 24 |
| Moki | .61 Long Stroke all models | 1/4" - 28 |
| Moki | .51RC | 6.0 x 1mm |
| Morris | .45 - .60 | 8.0 x 1.25mm |
| MVVS | .15 - .61 | 6.0 x 1mm |
| OS | .20 - .50 all models, .61SFN-H Ring, .61RFN-H ABC, FS-26 Surpass, FS-40 Surpass |
1/4" - 28 |
| OS | .60FP ABC, .61SF all version, .61RF ABC, .61RF-P, .61RX-H, .61SX-H, .61VR-M ABC, .65VR-M ABC, .65VR-DF ABC, .91VR-DF, .81VR-M, .91FSR, FF-240, FS-70 Surpass, FS-91 Surpass, FS-120 Surpass II, FS-120 Surpass SP, FS-61, FS-90, FS-120, FT-120II, FT-160 |
5/16" - 24 |
| Picco | .21 - .45 all models | 1/4" - 28 |
| Quadra | Q-35 | 5/16" - 24 |
| Rossi | .21 | 6.0 x 1mm |
| Rossi | .40 - .90 | 8.0 x 1.25mm |
| Royal | .25RC BB ABC, 28RC BB ABC, .40RC ABC Schnuerle, .45RC BB Schnuerle ABC, .46RC BB Schnuerle ABC |
1/4" - 28 |
| Saito | .40 - .60 4-C | 6.0 x 1mm |
| Saito | .65 - .90 4-C | 7.0 x 1mm |
| Saito | 1.20 - 2.70 4-C | 8.0 x 1.25mm |
| Supertigre | .19 - .56 all models, .60G, 60ST | 1/4" - 28 |
| Supertigre | S-90K, S-61K, X61K ABC RE | 5/16" - 24 |
| Thunder Tiger | GP25, GP42, PRO25, PRO46, F-54S | 1/4" - 28 |
| Thunder Tiger | GP61, PRO61, PRO120, F-91S | 5/16" - 24 |
| Webra | .21 - .60 all models | 1/4" - 28 |
| Webra | .80 - .90 all models | 8.0 x 1.25mm |
| YS | all 2-cycle models | 8.0 x 1.25mm |
| YS | all 4-cycle models except .53 | 8.0 x 1.0mm |
| YS | .53 4-C | 6.0 x 1.0mm |