Done some mowing today and in places where the grass was green and lush it bogged down slightly but that got me thinking.

Utilizing f=mc2 would abetter mower be one that has gearing in the blades to increase rotational speed, plus heavy blades, but with a replaceable cutting edge. I accept you would need some sort of clutch to disengage to prevent shaft damage if you do meet an immovable object.

And even if you do need to step up the speed of the blades via going through a simple two stage gear to get to maximum speed would this make a better mower and no bogging down?

Skunkworks said:

Utilizing f=mc2 would abetter mower be one

That annihilates the grass with itself.

Wrong equation for your context.

OCDC said:

Skunkworks said:

Utilizing f=mc2 would abetter mower be one

That annihilates the grass with itself.

Wrong equation for your context.

Isnt that the energy and inertia one?

Just get more horses.

Skunkworks said:

OCDC said:

Skunkworks said:

Utilizing f=mc2 would abetter mower be one

That annihilates the grass with itself.

Wrong equation for your context.

Isnt that the energy and inertia one?

f=ma?

F=ma but that doesn’t take into consideration torque whose equations I forget.

Skunkworks said:

OCDC said:

Skunkworks said:

Utilizing f=mc2 would abetter mower be one

That annihilates the grass with itself.

Wrong equation for your context.

Isnt that the energy and inertia one?

nope. What is c in this context?

Angus Prune said:

Just get more horses.

500 cc already and there are engine size constraints. I was thinking of it from the direction it is only single speed and thinking of a better way to utilise the available power and not relying on the engine to drive it through the bad spots. Once up to speed it should go through anything within reason.

need high lift blades to get the grass up and out the chute. need better designed outlets imo.

OCDC said:

F=ma but that doesn’t take into consideration torque whose equations I forget.

doohhhh smacks head Should have googled first but you get the vibe.

Boris said:

need high lift blades to get the grass up and out the chute. need better designed outlets imo.

I agree, outlets need work and too much clearance between the sides and blade. Allows crud to build up affecting the discharge of grass and slowing it.

Angus Prune said:

Just get more horses.

NO! Not more horses!

You could look at some sort of constantly variable gearbox, to allow you to control the bias between blade rotation speed and speed of the mower. Hit a lush patch and you pull the lever so blades go faster while mower moves more slowly.

http://en.wikipedia.org/wiki/Continuously_variable_transmission

Skunkworks said:

Boris said:

need high lift blades to get the grass up and out the chute. need better designed outlets imo.

I agree, outlets need work and too much clearance between the sides and blade. Allows crud to build up affecting the discharge of grass and slowing it.

The crud builds up because of adhesion to the surface in the first instance. So a low friction polymer lining might help with that problem. This type of lining doesn’t have very good resistance to high stress abrasion though, so one patch of stones might destroy it.

My suggestion was a factory redesign, not a home or after-market modification.

party_pants said:

You could look at some sort of constantly variable gearbox, to allow you to control the bias between blade rotation speed and speed of the mower. Hit a lush patch and you pull the lever so blades go faster while mower moves more slowly.

http://en.wikipedia.org/wiki/Continuously_variable_transmission

But to my thinking that is a complication and requires monitoring. I was thinking more starting mower, engaging blades, let engine settle and recover revs, move to a second gear and higher speed, let engine settle again, then into drive and away you go.

party_pants said:

My suggestion was a factory redesign, not a home or after-market modification.

Me too, I was talking about a complete redo of all aspects.

Skunkworks said:

party_pants said:

You could look at some sort of constantly variable gearbox, to allow you to control the bias between blade rotation speed and speed of the mower. Hit a lush patch and you pull the lever so blades go faster while mower moves more slowly.

http://en.wikipedia.org/wiki/Continuously_variable_transmission

But to my thinking that is a complication and requires monitoring. I was thinking more starting mower, engaging blades, let engine settle and recover revs, move to a second gear and higher speed, let engine settle again, then into drive and away you go.

I think my neighbour has a mower like this. It sounds a bit like a Cessna when he gets it going.

> gearing in the blades to increase rotational speed

The longer and slower the blades, the lower the mower power requirements and better fuel consumption. So you want the lowest rotational speed that you can get away with.

Skunkworks said:

party_pants said:

You could look at some sort of constantly variable gearbox, to allow you to control the bias between blade rotation speed and speed of the mower. Hit a lush patch and you pull the lever so blades go faster while mower moves more slowly.

http://en.wikipedia.org/wiki/Continuously_variable_transmission

But to my thinking that is a complication and requires monitoring. I was thinking more starting mower, engaging blades, let engine settle and recover revs, move to a second gear and higher speed, let engine settle again, then into drive and away you go.

You could possibly automate it with electronics.

mollwollfumble said:

> gearing in the blades to increase rotational speed

The longer and slower the blades, the lower the mower power requirements and better fuel consumption. So you want the lowest rotational speed that you can get away with.

But you want to cut stuff and I am thinking to do that faster is better and better using the power available. I don’t want to gently brush the grass. Fuel economy is not a first or even fourth priority for my ultimate mower.

A good clean cut, so lifting of grass and neat ejection
Easy cutting without bogging down which strains components.
Reliability (which would include a facility to plug into mains to keep battery trickle charged)
Ease of maintenance including oil filters and changing blades or cutting edges
Quiet operation.

party_pants said:

You could possibly automate it with electronics.

No problems with that, just increasing the speed of the blade is the (or my) objective.

Skunkworks said:

party_pants said:

You could possibly automate it with electronics.

No problems with that, just increasing the speed of the blade is the (or my) objective.

Since they are both taking power from the same engine, and the aim is not to just apply more horsepower, applying more power to make the blades spin faster for better cutting means reducing the amount of power driving the wheels. A CVT is just the ticket to do this.

Skunky, you are basically just using the blade disc as a an energy storage mechanism by either making it heavy or spin faster. While it would work to a degree, it has the inherent danger of a lot of stored energy to go bang when something is outside of the intended design limits.

P_Ps idea sound much better. Quite clever in fact… I wonder where he stole it from…

Stealth said:

P_Ps idea sound much better. Quite clever in fact… I wonder where he stole it from…

probably that thread you started in August 2008

:p

Stealth said:

Skunky, you are basically just using the blade disc as a an energy storage mechanism by either making it heavy or spin faster. While it would work to a degree, it has the inherent danger of a lot of stored energy to go bang when something is outside of the intended design limits.

P_Ps idea sound much better. Quite clever in fact… I wonder where he stole it from…

Both really, heavier AND faster, I did say it needed a clutch for hard objects but yes that is essentially it, getting the blades up to speed and retaining that energy.

LOL… one of my friends posted this on FB tonight:

“After a recent spike in electric lawn mower sightings in the last week I plead with the Aussie public not to insult your lawns with these imitations and instead buy a real lawn mower!!!! you are not cutting the grass with these electric contraptions instead the grass blades are simply laying down and mooning you to return the insult!!!!”

Doesn’t actually answer the question asked at all, but it made me laugh.

fresnel_chick said:

LOL… one of my friends posted this on FB tonight:

“After a recent spike in electric lawn mower sightings in the last week I plead with the Aussie public not to insult your lawns with these imitations and instead buy a real lawn mower!!!! you are not cutting the grass with these electric contraptions instead the grass blades are simply laying down and mooning you to return the insult!!!!”

Doesn’t actually answer the question asked at all, but it made me laugh.

But do you mean a ‘reel mower’ or a ‘real mower’ as some would say that only reel mowers are real mowers, but I may not agree with that as I think for some application non-reel mower are unreal mowers.

mollwollfumble said:

> gearing in the blades to increase rotational speed

The longer and slower the blades, the lower the mower power requirements and better fuel consumption. So you want the lowest rotational speed that you can get away with.

This is why the blades connect to a governor. If the lawnmower isn’t governing itself via the speed of rotation in the grass then the governor needs adjustment.

could you add a little turbo charger or a super charger to a two stroke or four stroke for those bog down bits?

or an automatic gear system that engages more torque at the bog down bits

An engine builder mate of mine rebuilt his two-stroke Victor push lawnmower, did a porting job, bigger carby, and a megaphone exhaust.
Reckoned he could run through grass knee-high with it and it’d just chew through the grass no probs.

Spiny Norman said:

An engine builder mate of mine rebuilt his two-stroke Victor push lawnmower, did a porting job, bigger carby, and a megaphone exhaust.
Reckoned he could run through grass knee-high with it and it’d just chew through the grass no probs.

That’s what I need. I’ve got Bahir that make 100hp tractor/slashers struggle.

Ian said:

Spiny Norman said:

An engine builder mate of mine rebuilt his two-stroke Victor push lawnmower, did a porting job, bigger carby, and a megaphone exhaust.
Reckoned he could run through grass knee-high with it and it’d just chew through the grass no probs.

That’s what I need. I’ve got Bahir that make 100hp tractor/slashers struggle.

I’ve got one in the shed my father left me. He bought it secondhand long ago when I was a mere lad, because it was self propelled since he’d not long recovered from major bowel surgery at the time. I still recall with amusement watching him Legs flying in the wind as it dragged him around the backyard. Goes like a rocket. Has a Villiers 19 cc motor and a fuel tank that holds a coffee cup of fuel.

Skunkworks said:

Done some mowing today and in places where the grass was green and lush it bogged down slightly but that got me thinking.

Utilizing f=mc2 would abetter mower be one that has gearing in the blades to increase rotational speed, plus heavy blades, but with a replaceable cutting edge. I accept you would need some sort of clutch to disengage to prevent shaft damage if you do meet an immovable object.

And even if you do need to step up the speed of the blades via going through a simple two stage gear to get to maximum speed would this make a better mower and no bogging down?

And in the ultimate mower the deck should e made of plastic so it doesn’t rust.

Nice little drop of rain, the first in some time.
It’s not your stormyafied type rain it’s more your gentle autumn rain.
When you’re a cattle barren you start to notice these things.

Skunkworks said:

And in the ultimate mower the deck should e made of plastic so it doesn’t rust.

Preferably, self cleaning polymer.

Peak Warming Man said:

Nice little drop of rain, the first in some time.
It’s not your stormyafied type rain it’s more your gentle autumn rain.
When you’re a cattle barren you start to notice these things.

Short a few cows in the paddock, mate?

Peak Warming Man said:

Nice little drop of rain, the first in some time.
It’s not your stormyafied type rain it’s more your gentle autumn rain.
When you’re a cattle barren you start to notice these things.

I hope you are chewing on a bit of bark and squinting when you say that. Aye, nice gentle overnight rain here as well. Puddles everywhere and now overcast. Gonna be a good spring.

(voice=Clarkson from Topgear) MORE POWER!(/voice)

Rule 303 said:

(voice=Clarkson from Topgear) MORE POWER!(/voice)

Isn’t this more a Tim “The Toolman” Taylor type thing?

Stealth said:

Isn’t this more a Tim “The Toolman” Taylor type thing?

Sure, if you’re old enough to remember him.

;-)

Rule 303 said:

Stealth said:

Isn’t this more a Tim “The Toolman” Taylor type thing?

Sure, if you’re old enough to remember him.

;-)

I read history books…

Stealth said:

I read history books…

I think I recall my Grandfather telling me about him when I was a child…

Rule 303 said:

Stealth said:

I read history books…

I think I recall my Grandfather telling me about him when I was a child…

When you ‘were’ a child? Have you grown up already???

Done some mowing today and in places where the grass was green and lush it bogged down slightly but that got me thinking.

f = mc2?

a mower with blades moving at light speed?

this I would like to see