Rotary cutter bladt tip speed?

[Fredex]

Is the BTS slower with a 65HP tractor at 540rpm than with a 90hp tractor at 540rpm?
QUOTE]

Nope. Blade tip speed depends purely upon pto rpm, gearbox ratio, and blade radius. HP has no effect on BTS so long as pto rpm remains at 540.
Fred

 

[firemanpat2910]

how many mph in a fpm ? how much difference does it realy make? what % faster is 17803 than 16000? too much math for me. I just want to finish work and go play with my tractor!!!!!!!!!!!!!!!

 

[rozett]

what % faster is 17803 than 16000?

11% faster

how many mph in a fpm

1 mph = 88 fpm so..... 17803 fpm = 202 mph

 

[Richard]

how many mph in a fpm ? how much difference does it realy make? what % faster is 17803 than 16000? too much math for me. I just want to finish work and go play with my tractor!!!!!!!!!!!!!!!

Well, using the bushhog verses the Brown

17,803 fpm / 11,875 fpm is 49.92% increase with the Brown at the same PTO speed!



No wonder it diced everything up a LOT more than the regular cutter we use. I honestly don't think our IH-444 gets to full RPM's, and if that is right, then I'm never using it at PTO rated speeds. (tach doesn't work right, or if it DOES, then I'm right and we're probably 65% of PTO speed)

 

[Richard]

Oops, my apologies, I didn't notice the qualification as to WHICH speeds you were referring to...

 

[Soundguy]

What also needs to be taken into acount is that longer blades will have a higher tip speed.. all else being equal.

soundguy

Seems to me if the blade is turning faster and has the torque to go with it, it should cut anything (that will cut) better than a slower blade with the same amount of torque-

With that being said, what about the gearbox and the ratings? Is the Brown BTS based on 120HP which is what the gearbox is rated at? Is the BTS slower with a 65HP tractor at 540rpm than with a 90hp tractor at 540rpm?

Farmwithjunk - your BH286 BTS is rated at 14,877

"For higher BTS, the damage to the equipment might be worse when you hit a buried steel pipe, large rock, stump etc. It would sure have more whacks before the clutch could be stomped or the 3pt raised. "

Johnbud - Is this true if the slipclutch is properly adjusted?

 

[Farmwithjunk]

Seems to me if the blade is turning faster and has the torque to go with it, it should cut anything (that will cut) better than a slower blade with the same amount of torque-

With that being said, what about the gearbox and the ratings? Is the Brown BTS based on 120HP which is what the gearbox is rated at? Is the BTS slower with a 65HP tractor at 540rpm than with a 90hp tractor at 540rpm?

Farmwithjunk - your BH286 BTS is rated at 14,877

"For higher BTS, the damage to the equipment might be worse when you hit a buried steel pipe, large rock, stump etc. It would sure have more whacks before the clutch could be stomped or the 3pt raised. "

Johnbud - Is this true if the slipclutch is properly adjusted?

Glad to know that about my 286 mower. It'll mow anything a medium duty cutter should as far as brush and weeds, plus does a good job of mowing grass. Real smooth cut in anything.

Gear box ratings are a recommended maximum INPUT hp level. In other words, the biggest tractor you can use. It doesn't take that much power to run it.

A slip clutch doesn't do much to lessen the initial impact when a mower blade strikes, let's say that buried steel pipe. Also, a fair amount of driveline shock goes back through the tractor. That is why the high horsepower recommendation on the Brown, or any of the heavy duty mowers. It's best to have them on a big enough tractor to take what the mower can and will dish out.

One more thing. Take a look at Rhino's heavy duty brush cutters. Their heavy duty equipment is what put them on the map. Good stuff!

 

[chrisjbell]

One more thing. Take a look at Rhino's heavy duty brush cutters. Their heavy duty equipment is what put them on the map. Good stuff!

I'll second that recommendation. My Rhino cutter works great, takes a lot of abuse, and I have *no* idea what the blade tip speed is ;-)...

 

[1bush2hog]

My Rhino cutter works great, takes a lot of abuse, and I have *no* idea what the blade tip speed is ;-)...

If you are interested you can find the info here

TW84

 

[N80]

Gear box ratings are a recommended maximum INPUT hp level. In other words, the biggest tractor you can use. It doesn't take that much power to run it.

I think you're right, but the specs on my JD LX-6 do give a minimum pto hp requirement (22 hp), which seems odd. Under the gear box specs it lists 'hp rating' as 60, which is the max I guess. The BTS is 15,000. Cuts grass pretty cleanly. Its rated a only 1" trees but it breezes through 2" pines, locusts, and plums. I've never tried 3", and probably won't