Seeking advice on lawnmower purchase
- Thread starter Armand
- Start date
bertsmobile1
Lawn Royalty
Mowers will only mulch properly over a very finite height range and that range will depend upon the airflow characteristics of the deck & blade system.
In the USA this is made even harder as swing back blades on discs are considered too dangerious so you are relying on a 2" wide strip of steel to suck the grass up so it can be cut then twirl the clippings around, recutting them several times before depositing them back between the stems of the remaining grass, It is a real tall order. Take all the blades off your cars fan bar 2 and see how much air it shifts.
Despite the fact they put 6 to 10 height settings on mulching mowers, most will only mulch properly on the top few settings.
Then within the mulching height range of your mower, there will only be a couple of settings that will work with your particular grass type & density.
On top of that, the chopped up grass has to have somewhere to go thus the 1/3rd rule and in reality 1/4 would be closer to the mark if you want the clippings to vanish without trace.
Mulching requires a lot more energy than just cutting which is why the mulch only mowers usually have the largest engines.
It is a problem I get presented with almost daily but people just can not seem to understand mulched grass has to be cut no lower than 2.5".
If you want it lower than than then you need to get a reel mower and mow daily like they do on golf courses and bowling greens ( do you have lawn bowls in the USA ?)
In the USA this is made even harder as swing back blades on discs are considered too dangerious so you are relying on a 2" wide strip of steel to suck the grass up so it can be cut then twirl the clippings around, recutting them several times before depositing them back between the stems of the remaining grass, It is a real tall order. Take all the blades off your cars fan bar 2 and see how much air it shifts.
Despite the fact they put 6 to 10 height settings on mulching mowers, most will only mulch properly on the top few settings.
Then within the mulching height range of your mower, there will only be a couple of settings that will work with your particular grass type & density.
On top of that, the chopped up grass has to have somewhere to go thus the 1/3rd rule and in reality 1/4 would be closer to the mark if you want the clippings to vanish without trace.
Mulching requires a lot more energy than just cutting which is why the mulch only mowers usually have the largest engines.
It is a problem I get presented with almost daily but people just can not seem to understand mulched grass has to be cut no lower than 2.5".
If you want it lower than than then you need to get a reel mower and mow daily like they do on golf courses and bowling greens ( do you have lawn bowls in the USA ?)
What is it that makes the mower a good mulcher? is it the power of the motor? the type of blades? The particular Toro model I mention (20371) has a 6.75/149cc Kohler which apparently is not as powerful as the 7.25/163cc Briggs or the Honda GVC160 that is in the two Husqs. that I mentioned---would the Toro with the less powerful motor still much better than those two Husqs.?
bertsmobile1
Lawn Royalty
It is a complicated mixture of deck shape, deck height above the blades, shake of the blades that controls the airflow under the deck.
This is why dedicated mulching decks always mulch better than the universal decks that are universally poor at catching, poor at mulching , poor at throwing and poor at windrowing.
It is made even harder with bar blades because the blade is only at one 2" wide spot at any one time so you are relying on the momentum of the air where the blade was to carry n the process till the blade gets back there again.
Because you are double or trebble cutting the grass you need a bigger motor to mow at the same walking speed mulching as you do strait cutting.
Two strokes seem to work a lot better than 4 strokes.
We used to get a 19" mulch / catch fitted with a 6.25Hp 2 stroke power torque, or a CV 160 5.5Hp Honda or a 6.25 Hp briggs.
The honda choked so bad it got replaced with the CV 190 rated at 6.5 Hp and it was still way underpowered.
Yet the exact same motor will rip through 2' tall grass on a 22" wide self propelled mower and the smaller 160 will rip through 22" when fitted to a plain push mower.
The briggs engine was a joke and chokes on anything more than a 1/2" cut.
I lend out the 2 strokes while I repair customers 4 strokes and few are in a big hurry to get their old mower back again.
The chassis & blades are identical only the engines were different.
Then you need to consider the type of grass.
Broad leaved grasses that are quite heavy will behave differently in the air flow to fine tubular leaved grasses
This is why dedicated mulching decks always mulch better than the universal decks that are universally poor at catching, poor at mulching , poor at throwing and poor at windrowing.
It is made even harder with bar blades because the blade is only at one 2" wide spot at any one time so you are relying on the momentum of the air where the blade was to carry n the process till the blade gets back there again.
Because you are double or trebble cutting the grass you need a bigger motor to mow at the same walking speed mulching as you do strait cutting.
Two strokes seem to work a lot better than 4 strokes.
We used to get a 19" mulch / catch fitted with a 6.25Hp 2 stroke power torque, or a CV 160 5.5Hp Honda or a 6.25 Hp briggs.
The honda choked so bad it got replaced with the CV 190 rated at 6.5 Hp and it was still way underpowered.
Yet the exact same motor will rip through 2' tall grass on a 22" wide self propelled mower and the smaller 160 will rip through 22" when fitted to a plain push mower.
The briggs engine was a joke and chokes on anything more than a 1/2" cut.
I lend out the 2 strokes while I repair customers 4 strokes and few are in a big hurry to get their old mower back again.
The chassis & blades are identical only the engines were different.
Then you need to consider the type of grass.
Broad leaved grasses that are quite heavy will behave differently in the air flow to fine tubular leaved grasses
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