Loader Brush Mower Question

[NCMau]

I am working on a 30 in, one blade deck to be mounted in front of the bucket. The engine is a 12HP vertical rotating CW couple with V belt. The blade spindle is LH tread. My assumption is if this deck would hit something hard, the blade nut would loosen. I am looking for a suggestion to deal with this situation. Would a double nut do it? Maybe you guys have a better idea. I do not want to be under a constant worry that the blade would come loose.
I will post pics when the project is completed. It is a simple idea which I think would work great for a small brush mower.

 

[beeforty]

In 20 years on my rider mower I've run over all kinds of things, dinged blades, stopped and smoked the belts and the nuts have never come loose.

 

[mikehaugen]

I am working on a 30 in, one blade deck to be mounted in front of the bucket. The engine is a 12HP vertical rotating CW couple with V belt. The blade spindle is LH tread. My assumption is if this deck would hit something hard, the blade nut would loosen. I am looking for a suggestion to deal with this situation. Would a double nut do it? Maybe you guys have a better idea. I do not want to be under a constant worry that the blade would come loose.
I will post pics when the project is completed. It is a simple idea which I think would work great for a small brush mower.

Engines are referred to cw or ccw by looking at the shaft end. If you do in fact have a cw spinning verticle shaft engine (can't say I've ever seen one) then that is perfect for left hand thread as it would tighten from blade resistance.

If you in fact have a ccw engine, the I'm not sure what would hold the nut on, double nut would probably have the best chance, but I would bet on it. Where did you get this left hand threaded spindle?

 

[NCMau]

Engines are referred to cw or ccw by looking at the shaft end. If you do in fact have a cw spinning verticle shaft engine (can't say I've ever seen one) then that is perfect for left hand thread as it would tighten from blade resistance.

If you in fact have a ccw engine, the I'm not sure what would hold the nut on, double nut would probably have the best chance, but I would bet on it. Where did you get this left hand threaded spindle?

Let me clarify my statement. The present vertical engine runs CCW looking at the shaft. (Using the wrong terminology, I was referring from the top of the spindle pulley). The deck originally was run by a horizontal engine coupled to the deck pulley with a 90 deg. belt configuration.
So I need a RH thread for the blade nut. I agree that a double nut is not going to do it. A simple solution would be a castle nut and a hole and cutter pin through the shaft and l probably try this method first.
A more complicated solution would be cut the threaded segment of the shaft and machine a new RH threaded portion. The spindle is long enough to meet the need. Thanks for the reply.

 

[mikehaugen]

Not sure a castle nut is a solution either. The nut will either loosen just enough to let the blade spin (I never have good luck getting castle nuts "just tight enough") or you may sheer the cotter pin. I guess I would give it a try though.

If you could somehow route the belt with a twist in it it would kind of solve your problem, but I doubt you could find a blade to spin the correct direction.

 

[NCMau]

Not sure a castle nut is a solution either. The nut will either loosen just enough to let the blade spin (I never have good luck getting castle nuts "just tight enough") or you may sheer the cotter pin. I guess I would give it a try though.

If you could somehow route the belt with a twist in it it would kind of solve your problem, but I doubt you could find a blade to spin the correct direction.

Twisting the belt is a good idea but I don't have much room between the engine and the spindle pulley. I certainly will give it a try. The blade is a 3/8 in bar with replaceable ends, so that's not a problem.