[99flhr]

After sharpening ( lots of file strokes!) I installed my recently arrived set on my RM-48.
No clearance issues or uncut strips.
Cut quality seems good

 

[screamineagle66]

Your demeanor seems ho-hum ? I've considered buying these blades, but I've yet to see anyone say WOW !! These are great, and worth the price !!

Am I interpreting correctly ?

 

[Bart]

Your demeanor seems ho-hum ? I've considered buying these blades, but I've yet to see anyone say WOW !! These are great, and worth the price !!

Am I interpreting correctly ?

I would say the blades work very well and have an advantage over the OEM blades with respect to mulching. The cost is relatively high but, over time, I think the cost would be lower due to the longer life expectancy of the blades and the lower cost of replacing just the blade "tips".

My assessment is that this is a product aimed at the commercial market where the payback comes from lower labor to deal with grass/leaf clippings as well as the replacement costs of the blades when used 40+ hrs a week. In my case, with 4 separate tractors that I use from time to time for mowing a total of about 3 hrs a week, it's not likely that I will realize any $ savings and certainly won't set up all of my mower decks with these blades. However, as mentioned in a previous post, I am pleased with how they perform and will continue to use them when I have conditions that require good mulching.

 

[99flhr]

Your demeanor seems ho-hum ? I've considered buying these blades, but I've yet to see anyone say WOW !! These are great, and worth the price !!

Am I interpreting correctly ?

More testing will be required but, I really only expected incremental improvement. After all, deck design plays an important part in cut quality and the C/I deck already cuts quite well.
I`m going to make side by side passses with the 446 (standard blades) and the 4020 (Meg-mo)
I assume the difference will be negligible.
The Meg-mo blades are loud, it`s a harmonic sound that cycles up & down ( both decks have new bearings etc)
Have wispy grass in shaded areas and it would seem the Gator blades I removed created more lift/suction
Only time will tell if they MM`s stay sharper/longer and if they are more susceptible to damage. At my place you`re going to shave a tree root eventually

I should add that I enjoy mowing and like the yard to look good, so rarely if ever does the grass get deep

The Gator blades hooked to a collection system would mulch leaves that were so deep that the leading edge of the deck was snowplowing leaves as you went (slowly)

 

[99flhr]

I think the cost would be lower due to the longer life expectancy of the blades and the lower cost of replacing just the blade "tips".

MM Knives are $5 each x 12 = $60 IIRC the last blades I purchased from Brian were $18-$22 each ( ?)
The Gators came with the 4020 so I have no idea as to cost.

Edit: I will add (whine) that installing the center MM on a r.h. deck requires that you have 3 arms or a prehensile tail.
Fortunately I have the latter

 

[Bart]

I gave the Meg-mos another workout today under more "normal" conditions and happily experienced none of the striping in the center that I mentioned earlier. I hear no whining from the blades but that's probably because the bearings on the deck I used are too noisy to hear much of anything. :sidelaugh: Yes, the bearings will be replaced one of these days.....

 

[Bob MacGregor]

I gave the Meg-mos another workout today under more "normal" conditions and happily experienced none of the striping in the center that I mentioned earlier. I hear no whining from the blades but that's probably because the bearings on the deck I used are too noisy to hear much of anything. :sidelaugh: Yes, the bearings will be replaced one of these days.....

Bart, I'm shocked, noisy bearings on one of Bart's machines!!!! How can that be???? :sidelaugh: Just how can that ever be!!!! :sidelaugh:
Mad Mackie in CT

 

[Bart]

Bart, I'm shocked, noisy bearings on one of Bart's machines!!!! How can that be???? :sidelaugh: Just how can that ever be!!!! :sidelaugh:
Mad Mackie in CT

I was wondering the same thing! My maintenance guy is a slacker--I'd fire him but my wife seems to like having him around.

 

[99flhr]

I`m going to make side by side passes with the 446 (standard blades) and the 4020 (Meg-mo)
I assume the difference will be negligible.

Field trials :mowlawn: have confirmed this theory ^ Mowing 2 days growth revealed no discernable difference in cut quality.
Mowing 3 weeks growth showed the stock blades to be slightly superior. Both machines have new bearings , factory belts and testing was conducted at W.O.T. and "full" travel speed in Low range
For the average residential user looking for the "Wow factor" mentioned by Screamingeagle66, you won`t find it.
I have no complaints and will hopefully find a benefit in leaf removal season, if that proves to be dramatic then (and only then) would I order a second set for the 446.

JMO YMMV and all the requisite disclaimers. :sidelaugh:

 

[Bart]

It sounds like your field trials have validated mine! :thumbsup:

I have not discussed with Roy the optimum blade speed but I believe that is a critical factor in performance. I've been using an older J46 deck and imagine that replacing the drive pulley with a slightly smaller one would make a noticeable difference in how the blades handle 3 week growth.

There is no question in my mind that the mulching action is improved over the OEM blades and produces a "cleaner" look without having to vac. What hasn't been tested/discussed is how much more mulching might be achieved with the discharge chute blocked off. Roy told me that it would make a difference so I am thinking of having my maintenance guy install a baffle over the discharge area if/when he gets around to replacing the bearings.

 

[Hydriv]

Roy's video shows his blades being used on a ZTR and ZTR's are mostly commercial machines that are allowed higher blade tip speeds.

 

[99flhr]

I was under the impression that max was 19,000 fpm regardless of mower type. "IF" my engine is turning 3600, I calculate 19K at the blade.
Guess I need a tach to confirm this

 

[99flhr]

It sounds like your field trials have validated mine! :thumbsup:
so I am thinking of having my maintenance guy install a baffle over the discharge area if/when he gets around to replacing the bearings.

Have the factory mulch kit, unfortunately my "maintenance guy" is as lazy as yours. I`ll have to get him off his butt and install it. Seems like a lot of work for minimal gain. :headscratcher:

 

[Hydriv]

I was under the impression that max was 19,000 fpm regardless of mower type. "IF" my engine is turning 3600, I calculate 19K at the blade.
Guess I need a tach to confirm this

My understanding is that the legislation was enacted to provide protection to the homeowner market only. The commercial market did not have this limitation placed on it because ZTR's were specifically designed to make the people in the grass cutting business a lot more productive. If you increase the width of the mower deck and increase the ground speed, then it only stands to reason that you are feeding uncut grass into the deck at a higher rate of speed and the only way to handle this is to increase the tip speed. Government worked with the industry overall to frame the legislation. The homeowner industry really did not care because the legislation put all them on a level playing field and that was a good thing.

If the deck blades have a tip speed of 18,000 feet per minute, that translates into 204 miles per hour. So if the tip of the blade hits a solid object that was dropped on the lawn, then it can get fired out of the discharge chute at speeds up to that number. When you consider that the best hardball pitchers have a hard time hitting 100MPH, imagine being hit by a hard object leaving your deck.

If you move the tip speed to 22,000 FPM, then the ends of the blades are travelling at 250 MPH and that's faster than any race car or race bike on a race track that has curves. Drag strips and salt flats are excluded.

 

[Bart]

The higher speed is important for two reasons. First, it will make more cuts per second and reduce the grass clippings to a smaller size and it will also keep the swinging blades pointed straight out in heavier grass to produce a clean cut. The fact that the blades can swing should reduce the velocity of items of heavy objects such as rocks that may get thrown out of the chute so I would feel more comfortable running these blades at a higher speed than fixed blades.

 

[Bob MacGregor]

I will check blade RPM on both my 4018 and Scag Tiger Cub at the pulleys and then do the math to calculate blade tip speed. 4018 engine is at 3,600 RPM with deck running. Scag manual calls for 3,600 RPM but running at 3,200 presently. I may adjust it up some although I don't feel the need to as the Scag deck turns very fast.
I will get back to you all when I've done the checks and the math. Lazer tach is a wonderfull thing!!!
Mad Mackie in CT :mrgreen: :mowlawn:

 

[Bob MacGregor]

Hi Troops,
Here are my findings on my Scag Tiger Cub/26 HP ELS Briggs. I checked RPM with two lazer tachs and got the same RPM readings.
Engine at 3,600 RPM
Deck pulley 4,100 RPM on a STC48V Scag deck with 48" cut.
Blade diameter 16.5"
Blade tip speed is 17,710 FT/Min with collection blower running, without blower would be somewhat higher. Blower runs off R/H deck pulley.
I was looking in the parts manual for the Scag and as the decks get wider the deck pulleys increase in diameter. I take it that this is done to slow down the spindle speed as the blade diameter increases to keep the blade tip speeds within the same range.
My 4018 is at another location but I'm going there today and I will check it.
Mad Mackie in CT :mrgreen: :mowlawn:

 

[Bart]

My maintenance guy finally got off his fat butt and replaced the deck bearings. While he was at it, he installed the slightly smaller deck drive pulley to speed the blades up and installed a baffle to close off the discharge chute.

I tested it this PM but with all the heavy rain we've had the past couple of days it was not ideal mowing conditions but the mulching appears improved and the deck is whisper quiet. When things dry out I'll get a better chance to assess performance.

 

[99flhr]

The Meg-mo blades are loud, it`s a harmonic sound that cycles up & down ( both decks have new bearings etc)

Only time will tell if they MM`s stay sharper/longer and if they are more susceptible to damage. At my place you`re going to shave a tree root eventually

Noise gone, tree root hit, blades damaged and removed

 

[Bob MacGregor]

Hi Troops,
I got around to checking the blade tip speed on my 4018. It calculates to be 15,905 Ft/Min with the engine at 3,600 RPM. The outboard deck pulley was turning almost the same as engine speed. Blade tip speed in Ft/Min = 3.1416 X diameter of 16.875" X 3,600 divided by 12.
This 4018 has been repowered and has a 5 3/8" diameter clutch pulley. If I recall, the stock clutch that came on the P218 Onan has a 5 1/4" diameter pulley and the blade tip speed would be slightly slower.
Those of you that have 200 and 400 series machines with J-N 44 and J-N 46 decks can increase blade tip speed by doing two easy things. Checking the engine RPM and raising it to 3,600 RPM and replacing the deck drive pulley with one for a J-N 40 deck which is a smaller diameter. I did this on my 1985 448 and did not have to change belt size.
My 448 has a new owner so I'm not able to check the blade tip speed.
I am going to stay with stock blades on my machines as rocks and roots are a problem and airflow is critical to effective collection systems.
Bob MacGregor in CT :mrgreen: :mowlawn: