How would you measure tip speed on a hydraulically powered mower blade?

4570Man

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Yes, but that can vary with throttle on the engine, which varies the RPMs of the pump, affecting flow calculations. I'd need an engine tachometer and assume that the 20 year old pump and motor, and hoses, valves, etc... have no leakage, slippage etc....

I'd like to measure right at the beast itself. ;)

That’s what I was going to say next. Measuring it with a measuring tool is the only sorta accurate way I can think of.
 

dalola

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This seems like an interesting project.

The question came up to me of "what is the tip speed of your mower blades?"

The mower deck is hydraulic, so the only shaft I could measure speed on would be the shaft coming out of the hydraulic motor. The center spindle is direct driven by that shaft, so it would be accurate.

I used to have access to a tachometer that has a wheel I could press on the shaft to get speed. Then I could calculate from that. I don't have access to that tach anymore.

How would you go about measuring the RPMs of that shaft?

Oh, you're in up to your knees now! When you get up to your nose, hopefully you'll forget who asked you such a silly question....:confused3:;)
 

s219

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I would have said "strobo-tach" but I am an old school lab engineer. I bet there are better ways nowadays (probably an iPhone app).
 

dalola

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Or, you could just call the mfg'r, and see if they have any data... :drink:
 

RickB

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Tip speed and blade condition will determine cut quality. There are only two categories of tip speed; enough and not enough. If your blades are sharp and the cut quality suits you, your tip speed is adequate.
Next question please.
 

4570Man

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Tip speed and blade condition will determine cut quality. There are only two categories of tip speed; enough and not enough. If your blades are sharp and the cut quality suits you, your tip speed is adequate.
Next question please.

You obviously missed the point. He’s had the mower for 20 years and is obviously happy with it. This is a problem solving thread.
 
 
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