Item 0349

MAKE: SynchroLite ~ Power Train (2 engine) - Mast - Machining

Drawing:

 

See Machinery Handbook 25 page 2055 for required spline drawing data to be added. Most is on FORM

Spline: (for synchro gears and option for ratchet)

See: OTHER: Mechanical - Spline B276

Working Info:

Torque from an engine (w/ application factor of only 1) = 253.4 ft-lb = 3,040.8 in-lb

Pitch Diameter of Spline 1.1 to 1.3" [MH25 ~ fig. 1 ~ p 2057]

Maximum Effective Length = 1" [MH25 ~ fig. 2 ~ p 2057]

Tentative Specifications:

 

 

Spline for Overrunning Clutch

Spline for Synchro Gear

 

Involute Spline or Involute Serration?

 

 

 

45 ºº pressure angle or 37.5 º?

 

 

 

Tolerance class = ?

 

 

 

Press fit

Press fit?

Press fit

FORM: PT - Mast - Spline Synchro gear [Pd] should read 20/40 also No. of teeth is 30 & spline length is 1.25"

Spline for Overrunning Clutch

Spline for Synchro Gear

The data on the above forms must be checked. Also data on loading has been added.

Suppliers:

There are 2 companies in BC that can spline shafts. One is in Abbotsford and one is in Richmond.

Spline re Tapered Roller Bearing & Mast

The ID of the bearing #0527 is 1.3780"

The recommended minimum shaft OD for this bearing is 1.6534"

There for the minimum spline depth is 0.2754"

 

The key size for shafts 1-5/16 to 1-3/8" is 5/16 * 5/32" (0.15625")

 

Spline size: 1" shaft OD & 48 splines

Spline size: 3/4" shaft OD & 36 splines

 

1.375' diameter * pi = 4.3214" circumference.

The following is just a guess at spline data.

4.3214" / 0.5625" = 25.6571 

Keyway: (option for ratchet attachment)

This has the advantage over a spline in that bearings, with an ID of the shaft, can be slid over the keyway whereas they can not get by a spline. For mast strength at the keyways, the bore could have a smaller ID at this location. There is a company in California that does long boring - they were at the Aerospace exhibition.

 Notes:

Machine mast outside diameter slightly less then bearing inside diameters in areas where there are no bearings etc.

Consider extending the starboard shaft downward approximately 0.5", cut the spline teeth full depth and drive the fuel pump off of this extension.

Machining Sources: (titanium & spline) 

Local

Canam No

Acro Aerospace No

Helipro I think he said that he will phone back.

Vancouver Gear Yes Dave Sykes.

Ebco Not yet phoned

Avcorp Not yet phoned 

Jesus Nut:

If the Jesus nut can be located at the lower end, in the synchro, it should increase the rotor hub to blade clearance.

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Last Revised: December 7, 2000