Mower Deck Blades

[C.M.C-175 0]

Just Curious... Has anyone increased the speed their mower deck blades? Like with different pulley size or other means that I have not thought of? I have often thought (daydreaming while mowing) about it. It seems that it would be a benefit to speed them up faster, which I would think cut better and not have to rev the engine up as high. Any thoughts... good or bad???? :USA:

[tarcoleo 119]

Craig-

If you speed up the mower blades, you will take power from the tractor drive,

increase the wear rate of the deck bearings, raise the noise level, and possibly

not cut any better than you do at the design configuration. On the other hand,

there might be an advantage to increasing the ground speed of the tractor

a little. I cut at high range/3rd gear with a 48" deck on two "C" chassis' and

imagine I could do almost as well just little bit faster. Anybody do this? The

problem would be sheaves and belt changes, and maybe reconfiguring the

idler sheave so as not to lose traction. Dunno.

Tom in RI

[C.M.C-175 0]

Maybe its the kind of grass that I have or maybe that its very dry, but the faster I go the worse the cut gets. If I am barely moving, it seems to cut pretty good, but would take me forever to mow. My mower deck is in excellent shape and I am using brand new sharp blades. I dunno, maybe I am being too anal about the whole thing. Thanks for the reply's.

[bowtieguy 334]

I mow w/48" deck on 312-A just a fast as I can hang on!!....check your blades, bet you have them on up-side down>> :USA:

[Pettybilt 3]

Here is something i found on the web about blade speed. I just mowed knee high grass yesterday in 2nd on a 416-8 with no problems. Although i sharpen my blades with a grinder, then take a file to put a knife edge on them.

As far a engine speed, i've always been told its best to run a air cooled engine full trottle, they runs cooler.

"Blade-tip speed and safety You also should ask about the blade-tip speed of the mower. Many contractors believe that increased blade-tip speed increases overall productivity. This is true to a certain degree, but as blade-tip speeds increase, safety decreases. You must be careful to control the delicate balance between safety and the promise of added productivity".

[gwest_ca-(File Mod) 10,515]

From a Chilton manual that states - the top

governed engine speed must be set so maximum blade tip

speed is kept to less than 19,000 feet per minute. They

then suggest setting the governor 200 rpm low to allow

for possible error in tachometer reading.

A 14" blade at 5183 rpm or a 15" at 4838 rpm equals 19,000 fpm.

Garry

[tarcoleo 119]

Just for what's it worth, 19000 fpm is 216 mph. Not yet breaking the

sound barrier. Go faster if you dare.

Tom in RI :)

[C.M.C-175 0]

Thanks for all the responses. I know my blades are on correctly, I know that is easy to do, but they are correct. Pettybuilt, I sharpen my blades the same way, with a grinder, balance and finish off with a hand file. When my blades are really sharp I don't seem to have any issues. Maybe I'm waiting too long between switching out blades. :)

[dcrage 621]

So back to the safety thing -- Seriously there is a speed that will cause the blades to come apart (especially if you hit something) -- Now I assume there is a huge safety factor built into the manufacturing of the blades, but I don't know any of the specifics -- Any metal experts out there that can add some real facts about blade safety/integrity