OT optimal cutting speed and feed rate for lawn mower blades?

[Freedommachine]

What model JD are you using?

GX345.

 

[EPAIII]

It was a joke. I forgot the smiley face.

I've been mowing it all with the JD for nearly 10 years. It takes nearly 3.5 hours, 48" deck is too small. Although the Bolens leaves a less than desirable finish, it has knocked an hour off of the total time.

I am confident that increasing the blade speed, replacing the running gear with a well designed caster system and doing away with the integral chute portion of the deck will provide results that I can be content with.

It really is a nice little garden tractor, whoever had it before me took very good care of it. It has plenty of power and uses less than half of the fuel that the JD consumes. JD = 5 gallons of gasoline to mow the yard. Bolens = 2 1/4 gallons of diesel for the same task.

For what I paid for the Bolens, I really have no reason to complain. I'd like to get a 60" Hustler but I cannot justify the price, considering that the only thing it's good for is mowing grass.

This experiment is more fun anyway. It doesn't take much time to fab up a good wheel kit and swap out a few pulleys. So far I get the feeling that most riding mowers stay around 16k SFM to ensure that they are well under the maximum limit and also pass the projectile test.

While we can all speculate, none of us actually know what the results will be from a drastic increase in blade tip speed. I intend to fu€k around and find out .

 

[john.k]

My 1976 Deutscher mower is 1000% better made than the cheapie MTD(is $3000 cheap?) I bought last year.............I should have spent $600 on a new motor for the Deutscher ............anyhoo,the MTDs problem is it doesnt like grass ,the cutter deck just chokes with grass ,and will smoke the drive belt,then stall the motor ..............the reason the Deutscher works is the cutter deck is a flat steel sheet with two edges folded over .........the cut grass can escape freely and not choke up the blades.

 

[dkmc]

My 1976 Deutscher mower is 1000% better made than the cheapie MTD(is $3000 cheap?) I bought last year.............I should have spent $600 on a new motor for the Deutscher ............anyhoo,the MTDs problem is it doesnt like grass ,the cutter deck just chokes with grass ,and will smoke the drive belt,then stall the motor ..............the reason the Deutscher works is the cutter deck is a flat steel sheet with two edges folded over .........the cut grass can escape freely and not choke up the blades.

Most 'lawn tractors' have very shallow decks, made to cut 1-2" off the top of the lawn. Speed isn't a concern, that's why they have cup/bottle holders built it. Have a beer, relax, putt around the yard all afternoon. It's what home owners do on the weekend....

 

[Hodge]

The deck should not be level. It should be level side to side but actually should be tilted down towards the front. Level or tilted up in front will cause extra drag in heavy or wet grass. Enough to bog the engine in some cases. I set mine about 1/4" lower in front than in the rear. That gives you clearance sort of like on the bottom of an endmill (really more like heeling, but same result). I can probably check my JD 62" deck (also diesel) today and tell you how fast it spins.

Bingo, we have a winner.... also check for any slippage at the blade pulleys. Slip factor can sneak in and all your calculations go out the window.

 

[Hodge]

That's nuthin, they can wreck a perfectly good marriage in under fifteen minutes ...

View attachment 408916

Damn, I'd just hire her to cut the grass and not care how it looked....

 

[DouglasJRizzo]

I keep thinking of modifying my Toro ride on for better, more efficient cutting.

460 CUBIC INCH 575 HP BOSS CRATE ENGINE-REAR SUMP PAN

460 CUBIC INCH 575 HP BOSS CRATE ENGINE-REAR SUMP PAN|Ford Performance Parts

performanceparts.ford.com

 

[projectnut]

I keep thinking of modifying my Toro ride on for better, more efficient cutting.

460 CUBIC INCH 575 HP BOSS CRATE ENGINE-REAR SUMP PAN

460 CUBIC INCH 575 HP BOSS CRATE ENGINE-REAR SUMP PAN|Ford Performance Parts

performanceparts.ford.com

One of the guys I used to work with put a highly modified 460 in a JD 445 garden tractor and used it in several tractor pulling contests. There were several garden tractor pulling clubs in our area for many years. I still see a few outdoor arenas manicured for pulling but haven't seen much action in recent years. I think the pandemic had negative impact on many of the clubs. Most builders were in their late 50's or retired before the pandemic. They probably didn't want to take the chance of getting infected at the crowded contests.

 

[jerholz]

You guys need to start thinking outside the box. Well, maybe not this far outside the box.

 

[projectnut]

The idea of lazer mowing is not all that far out there. A company called Carbon Robotics out of Detroit recently introduced a lazer powered “cultivator” for row crops. It was demonstrated a few weeks ago on NBC news.

The machine travels slowly through the field detecting weeds in the crop rows. Lasers are then activated to burn them off. The machine is part of their effort to minimize the use of weed killers

You can buy them but you better be sitting down when you here the price. The current model sells for 1.3 million. It is totally robotic It can run 24 hours a day and replace 30 laborers

 

[john.k]

Ive been planning to put a hydraulic cutter head on a small excavator ......unfortunately used small excavators are outrageously expensive,especially the 5 ton size I want.

 

[Freedommachine]

The idea of lazer mowing is not all that far out there. A company called Carbon Robotics out of Detroit recently introduced a lazer powered “cultivator” for row crops. It was demonstrated a few weeks ago on NBC news.

The machine travels slowly through the field detecting weeds in the crop rows. Lasers are then activated to burn them off. The machine is part of their effort to minimize the use of weed killers

You can buy them but you better be sitting down when you here the price. The current model sells for 1.3 million. It is totally robotic It can run 24 hours a day and replace 30 laborers

Now THAT is a modern innovation I'd get behind. Anything that reduces the use of weed killer / pesticides or GMO seed is absolutely worth it.

 

[Aejgx6]

my modified grasshopper picked up a rand-om 3/4 stud in the yard. The six yr old likes to run off with the scrap pile. Modifications can have unintended consequences. I bet that could have gave someone the forever nap.7





I

 

[Aejgx6]

Needless to say this mower moved to shop and got replaced with a newer Grasshopper. Not my favorite but locally made. The old Grasshopper is waiting donor bike for a Harley D repower.

 

[Bill D]

Back in the day they made steam tractors for farming that burned straw as they harvested the grain.
Bill D

 

[Bill D]

The right to wear a bikini while mowing the lawn

May 1966: The charges of indecent exposure, brought against 21-year-old Mary Lou Hood for mowing her lawn while wearing a bikini, were all dropped.

www.weirduniverse.net

 

[PDW]

My 1976 Deutscher mower is 1000% better made than the cheapie MTD(is $3000 cheap?) I bought last year.............I should have spent $600 on a new motor for the Deutscher ............anyhoo,the MTDs problem is it doesnt like grass ,the cutter deck just chokes with grass ,and will smoke the drive belt,then stall the motor ..............the reason the Deutscher works is the cutter deck is a flat steel sheet with two edges folded over .........the cut grass can escape freely and not choke up the blades.

I had a POS MTD mower, totally useless on my rough-ish block here in Tasmania.

Bought a Kubota 7200 with mid mount mower deck, PTO drive not a shitty slipping belt. No comparison at all, this thing turns bracken fern into mulch let alone grass.

Mostly the wallabies and kangaroos keep the grass down though.

PDW

 

[Glug]

I keep thinking of modifying my Toro ride on for better, more efficient cutting.

Nothing like a big block and open pipes to get the blood pumping.

 

[MwTech Inc]

Sort of buzzed over the whole thing....but when we were in business and the 19K law came out we had to purchase a dedicated RPM setup to test and verify blade speed before the customers unit could go out the door. That was directed at push/self-propelled mowers in the beginning.
Depending on the deck adding high lift blades can actually hurt cutting performance........too many variables , deck depth, shape, baffles, the list goes on.
Basically your stuck with setting the font of the BLADE (not the deck pan itself)1/8 to 1/4 lower than the rear, making sure your drive system is not slipping, engine is running at mfd's spec and then travel at whatever speed to get a good cut.....

 

[john.k]

Might be able to furlough the mower....El Nino is back ....the yard was wheel bogging wet ,jungle growing wet six months ago is bone dry ,all the grass has thinned and yellowed off ,the dirt is turning to dust where I drive on it.