Overhung load, extending output shaft

[SevenToFive]

I have a hollow output shaft gearbox that will accept a 1-1/8" solid shaft, I want to extend the output shaft of a gearbox by 6 inches from the face of output seal to the end of the shaft. The manufacturer states that gear reducer is rated 899 lbs with the hollow shaft or a solid shaft that extends 2.36 inches from the face of the output seal. I am looking for the shaft to support 200 lbs. I want to calculate the overhung load but all of the equations that I find seem to focus around having a pulley or sheave at the end of the standard output shaft, but we will not be adding a pulley or sheave to the end of the shaft. The equation in the gearbox manufacturers catalog is (HP*126000*Overhung Load Factor)/Pitch Diameter*Output RPM. The distance from the output seal/bearing must play a large roll in the amount of overhung load the gear reducer can take.

Does anyone have an equation I can use?

Thanks

 

[tkyoung75]

Is it saying that you can hang 899lbs on the shaft at a distance of 2.36" unsupported (underline unsupported). If that is the case then you double the distance, halve the load allowed if you get my meaning. Otherwise, if you are actually supporting the load you should be able to make the shaft as long as you like and it won't matter as long as your extension shaft does not put more than the allowable 'overhung' load on the gearbox bearings ... and doesn't cause a twist (edit: or weld) failure on your extension shaft.