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Is it just me, or is anyone else affected by an outbreak of gardening stuff not working?

Firstly the motor mower (4 stroke Briggs & Stratton) won't start when it's hot. Now the hedgetrimmer (2 stroke) exhibits the same symptoms. Both start and run fine on choke when cold. The mower continues to run when warmed up but if it stops, there is no way it will re-start. The hedgetrimmer just stalls after warming up a bit.

It's fresh fuel but not sure if it's E5 or E10. Given the extra oxygen introduced with ethanol, is everything going to be too lean to run properly now?

Or maybe just coincidence. When we get fuel back at the pumps I'll try the machines with some Premium.

If that doesn't work I'll start looking at battery or robot mowers and battery hedgetrimmers - anyone tried these yet?

Jerry

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i'd suspect the fuel and gumming up the carbs

i have long ago converted to elec mower - hedge trimmer and a long extension lead and a decent circuit breaker.

Jerry perhaps you could get the Staff/contractors to provided their own kit ?

 

H

Edited by Hamish
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Jerry

I along with a few others volunteer to cut the grass in our local grave yard.

We have a mottlly  collection of machines that display similar symptoms regularly. What always gets them going is a jolly good squirt of carb cleaner to get rid of the waxy rubbish in the tiny jets.

George 

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About a month ago my wife said that she would like a robot lawnmower, but the problem was that the one she wanted was about £3000.

“Pah !!! “ I said. “ I could make one of them things for under 50 quid !!!”

The result is not so elegant as a commercial one, but it uses exactly the same blades and it cuts the lawn fine.

It did cost less than 50 quid, although I had to rob the wheels off my compressor to  keep the cost down.

(And I did have most of the bits lying around anyway).

Charlie.

Mower2.jpg

Mower3.jpg

Mower4.jpg

Mower1.jpg

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52 minutes ago, Charlie D said:

About a month ago my wife said that she would like a robot lawnmower, but the problem was that the one she wanted was about £3000.

“Pah !!! “ I said. “ I could make one of them things for under 50 quid !!!”

The result is not so elegant as a commercial one, but it uses exactly the same blades and it cuts the lawn fine.

It did cost less than 50 quid, although I had to rob the wheels off my compressor to  keep the cost down.

(And I did have most of the bits lying around anyway).

Charlie.

Mower2.jpg

Mower3.jpg

Mower4.jpg

Mower1.jpg

Thats brilliant!

Stuart.

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Now that is enterprising!

I have had a Husqvarna 4300 robot mower ( we have 2500m2 to cut) for 4 years

Apart from a Motherboard burning out and taking 6 months to be replaced under warranty it has proved reliable over 2 000 hours and the cut is good.

The major problem is the periphery wire. The man who installed it buried it about 4cm down. Initial problem was moles sectioning the wire - easily repaired but finding the break over the 450m length taxed my patience. This spring the wire has simply corroded within the sheath, Husqvarna just don’t want to know, so I have to replace the lot this winter.

I have mixed feelings about the success of my investment. Initially I was impressed and interested in the technology but have become exasperated by the wire problem.

And anyway, mowing the lawn by traditional methods only takes 1.5 hours and is therapeutic……

james

Edited by james christie
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29 minutes ago, james christie said:

mowing the lawn by traditional methods only takes 1.5 hours and is therapeutic……

Ahh… But sitting in the sunshine, with a glass of wine watching a robot mow the lawn is incredibly relaxing, hypnotic almost.

Interesting to hear what you say about the perimeter wire corroding or being eaten by moles. Because our lawn is surrounded by flowerbeds (with one in the middle) I didn’t need a perimeter wire, I just rely on anti collision sensors (Three sets of ultra sonic ‘Radar’ devices on the front) so that when it gets a few inches from a bunch of flowers it stops, reverses and does a 70 deg turn before it carries on.

I have a friend who has a Husqvarna  and he said that a guy came out to bury the perimeter wire when he first bought it. I guess there is quite a charge if you need it replacing. Do you also need to have a power cable from the house to the “Charging garage” for the robot? More added expense to the initial cost I guess.

Charlie.

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In 1978, I bought a second-hand Hayter 18" rotary, walk- behind, with rear roller, which had a 4-stroke Briggs & Stratton. It cost me £100, which Maddy said was expensive, but I changed the oil every year and cleaned the air filter, and it kept running well until 2009, when repeated carburation problems convinced me to change.  It used to take me about three and a half hours to cut the lawn, so the machine got plenty of exercise.  I am not someone who changes cars or other machinery until necessary, so 31 years for £100 is not expensive!

In 2009, I bought, brand new, a SARP 19", which is made by KAAZ Corporation, has a Kawasaki 4-stroke engine and belt drive to both the roller and the blade.  I had a service by the supplier after 12 months, but since then have just made an annual oil change and have replaced the air filter element once.  Having moved to a smaller place in Thame, lawn mowing is now under two hours.

I turn off the fuel tap when putting the mower to bed in the shed, so it takes about 15 pulls on the starter because there's no manual tickler on the carburettor.

Both these machines have served me well, and I enjoy the exercise.

Our next door neighbour, who is considerably younger, but whose garden is about the same size as our previous plot, drives a lawn tractor, so gets almost no exercise when mowing.

Ian Cornish

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49 minutes ago, Charlie D said:

I guess there is quite a charge if you need it replacing.

The buzzards wanted 1 100€ to re-install the wire! I didn’t bother to reply to their offer!

Getting the juice to the charging station is a very minor problem - mine is behind the garage and a hole drilled in the wall was sufficient.

Tell us more about the anti-collision sensors. At the moment I have to build a loop around each flower bed, the outward wire is neutralised by the inward.

james
 

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Excellent job on the DIY robot mower, I'm impressed !

Two stroke strimmers etc are very fussy on getting the correct oil / fuel ratio.

Bob.

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Charlie, that is indeed brilliant. If Wayne doesn't put that on the front cover of TR Action there is no justice.

I generally quite like the walk, as others have said, therapeutic. It's getting rid of the cuttings that really annoys me. However, getting on with a bit of tinkering whilst the robot takes care of the lawn is very attractive.

Jerry

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I have quite a few bits of kit, a couple of chain saws, three mowers, strimers, pole saw. Recently I have started adding the TR's Duckhams additive to the fuel as well as the 2 stroke mixer. It may be a coincidence but they all seem to start easier than without. My guess is that it leaves the plug in better condition for the next restart, and the fuel is not supposed to go off as quickly.

Alan

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22 hours ago, james christie said:

Tell us more about the anti-collision sensors.

Hello All,

Thanks for the kind comments about the mower.
To be honest it was a lot easier to make than it looks.

 DIY digital electronics are cheap and plentiful these days and the internet is full of example code that you can cobble together and modify to suit whatever you need.

It is all based on an Arduino microprocessor board, which, in its simplest form consists of a bunch of input and output pins that feed into and come out of the main processor. What happens to those inputs and outputs depends on the software that you write.

The ultrasonic radar module has 4 pins. Ground and +5v, for the power supply, and one pin that has a pulse sent to it from one of the Arduino output pins, used to trigger the ultrasonic burst, and one pin that feeds the echo pulse via an input pin to the Arduino.

The time between when the pulse is sent and when the echo is received is used to work out the distance the module is from an obstacle. If the obstacle is too close (exact distance determined by the figure that you put in the code.) then the software branches off to give signals to the output pins that control the wheel motors direction,

So upon meeting an obstacle, the first thing to happen is that both wheels go into reverse for (say) 1 second. Then one wheel changes direction for (say) half a second. This has the effect to turn the mower. Finally both wheel motors are put back into the forward direction to allow the mower to go on it’s way until it meets the next obstacle.

See what I mean … just simple logic!

The picture shows the Ultrasonic module in more detail. If you Google  HC-SR04    (Less than £3 ) you can find a data sheet that has, I think, example code and wiring.

 

1 hour ago, foster461 said:

the fact that you had all those bits lying around. Where is the video of the machine in action ?

I have mentions before “Never throw anything away.”
I had most of the electronics in my workshop, I’ve been playing around with Arduinos for a couple of years

The wheel motors I bought at an auction 30 years ago (They came from a company that used to make electrically height adjusted desks) The cutter motor and housing came from a Fiat Punto heater motor that I bought in error thinking there was a problem with the one in our Fiat. Modern heater motors are surprisingly powerful.

And, as mentioned previously, the main wheels came off my compressor.
The rear castor came off an office chair that I scrapped 20 years ago. ( I knew it would come in useful one day...)

I’ll make a quick video in a couple of days. And post it here.

If anyone wants to do something similar it might be easier to start with a “Spares or repair” robot mower from eBay. Even if the electronic are dead, it easy enough to replace them with what I have made.

Hope you found that interesting, and apologies to Jerry if I have hijacked his thread a bit.

Charlie.

s-l1600.jpg

HCSR04.pdf

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1 hour ago, Lebro said:

I presume you program it in C ?

I've read that it's based on C++

I've played with BASIC since the 1980's,through GW BASIC up to VIsual Basic, well enough to get paid as a software contractor in the 1990's, but I find C++ different enough to be a hassle to get my head around.

Charlie.

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Here is a quick video.

It was too wet to cut, so I switched the blades off. (Even got a bit of wheel spin at one point)

It works the same way as the majority of the commercial ones do (Or so I believe) Just random directions and, eventually, the entire lawn will be cut.

Charlie.

 

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Very good, but it must go over the same ground quite a lot before it eventually cuts the whole lawn ?

Had you considered GPS based control, following a pre determined path ?

Bob.  (still think it's brilliant)

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2 hours ago, Lebro said:

...it must go over the same ground quite a lot before it eventually cuts the whole lawn...

True. I was a bit surprised when I discovered that most commercial mowers used the random pattern movement method, but it is the easiest to implement.
Arduino compatible GPS modules are cheap, and if I don’t lose interest I may try to modify things. (May start to get complicated though.)

GY-NEO-6MV2 is one module type. Take a look at

https://www.xarg.org/2016/06/neo6mv2-gps-module-with-arduino/


Some of the higher priced commercial mowers use GSP, but I don’t really understand how seeing as “Off the shelf” GPS systems are usually only accurate to 3-5 mtrs. I know that there are ways to improve the accuracy, but I get the impression they come at a huge cost. I’d love to know exactly how the commercial GPS empowered mowers do it.

I have a golfing friend who has a wrist based GPS to find the distance to the next hole. I looked up the ccuracy of such devices and most (Including Garmin, who know a thing or two about GPS) claim 3 to 5 mtrs, but one of the cheaper manufacturers claims 30 cms accuracy. I don’t know how they claim to do it though.

Charlie

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59 minutes ago, Charlie D said:

True. I was a bit surprised when I discovered that most commercial mowers used the random pattern movement method, but it is the easiest to implement.
Arduino compatible GPS modules are cheap, and if I don’t lose interest I may try to modify things. (May start to get complicated though.)

GY-NEO-6MV2 is one module type. Take a look at

https://www.xarg.org/2016/06/neo6mv2-gps-module-with-arduino/


Some of the higher priced commercial mowers use GSP, but I don’t really understand how seeing as “Off the shelf” GPS systems are usually only accurate to 3-5 mtrs. I know that there are ways to improve the accuracy, but I get the impression they come at a huge cost. I’d love to know exactly how the commercial GPS empowered mowers do it.

I have a golfing friend who has a wrist based GPS to find the distance to the next hole. I looked up the ccuracy of such devices and most (Including Garmin, who know a thing or two about GPS) claim 3 to 5 mtrs, but one of the cheaper manufacturers claims 30 cms accuracy. I don’t know how they claim to do it though.

Charlie

Most of the larger modern tractors have GPS to control field working and they are reckoned to be very accurate.

Stuart.

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37 minutes ago, stuart said:

Most of the larger modern tractors have GPS to control field working and they are reckoned to be very accurate.

Good point Stuart. I hadn’t really thought about that, Just like the surveying equipment you see people using on the roads. +/- 5 mtrs isn’t really very good if you want to build a flyover.

I’ve just looked into it a bit more and found this:

“When selective availability was lifted in 2000, GPS had about a five-meter (16 ft) accuracy. GPS receivers that use the L5 band can have much higher accuracy, pinpointing to within 30 centimeters (11.8 in), while high-end users (typically engineering and land surveying applications) are able to have accuracy on several of the bandwidth signals to within two centimeters,”

But I guess those systems come at a price. OK to fit into a £300,000+  piece of farm machinery, but a bit pricey for a garden mower.

I’ll look into what “The L5 band” is, and try to discover.

Charlie

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