A few years ago I replaced an NSI propeller with an Airmaster.
Subsequent to the exchange, I dismantled the NSI hub to see how it was
constructed.
I was surprised to find that small screws on the end of the planetary gearbox
assembly were all loose to the extent they would have fallen out except
for the fact the gearbox was encapsulated in a housing.
On making this discovery, I was surprised the prop had not exhibited any
mechanical
problems while pitch changing but I suspect it was only a matter of time.
I am guessing these are the same screws that Mike had shear in his hub ??
Im not sure if any locking agent was employed but if I was going to use the hub
again I would certainly use Loctite or similar on the threads of those screws.
Regards
Kingsley in Oz
Sent from my iPhone
> On 19 Jul 2019, at 11:22 pm, Pete <peterz@zutrasoft.com> wrote:
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> What caused them is to shear, and what can be done to prevent recurrence?
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>> On Jul 19, 2019, at 3:28 AM, Mike Kelly <mike@dommi.plus.com> wrote:
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>>
>> Thanks everyone for helping.
>> What we found is that 4 very small screws had sheared off the end of the
>> gear train housing, allowing the motor & gearbox assembly to rotate and snap
the supply wires to the motor.
>>
>> Now we are faced with the task of removing these small screws from the gear
housing and making good again.
>>
>> Will let you know when we are back up and running again. :?
>>
>> --------
>> MK
>>
>>
>>
>>
>> Read this topic online here:
>>
>> http://forums.matronics.com/viewtopic.php?p=490417#490417
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