Red bear, long grass mower on charcoal gas

Your work is excellent giorgio. So well thought out. Those lid hold downs are also kind of ingenious.

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Giorgio, does it have enaugh power to mow nicely?

How many kw you got out of the generator?

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Giorgio, excellent work. I canā€™t help but smiling - you seem to have a good supply of ss :grin:

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Giorgio, whats the blue housing under the scythe lever for? I dont have that on myne

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tom, the lids of the filters i can turn nearly in every position, this is a big advantage when connecting rubber hoses on different engines with the same gasifierā€¦

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kristijan, yes it mows fine and also has powerā€¦where i tried yesterday the grass is not so high because of much trees , it is a neighbours field or better woodlandā€¦in a week or so i will begin with hay on our fieldsā€¦this year is a nice grass because of plenty of rain in the last monthā€¦
how much kw?
i would give the question to another expert of sloveniaā€¦you know.
he can calculate this things better, i am really stupid with electric stuff, must learn moreā€¦
i will fix the generator on a kind of slide with a motor and gasifier, in way i can bring it also to difficult places in the forest for electric chainsaw cuttingā€¦and for welding of courseā€¦
the blue housing under the lever for the scythe is where the racing cart is fixed to the mower

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jan, i have only some flat ss sheet bought on market place for used stuff, except some pipes i must bend it mostly for different stuff like filter housings eccā€¦not always easyā€¦would be nice to have a roller sometimes, but bending around round stuff like propan tanks or iron piping works alsoā€¦i have a good assistent.

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The Acme engine is 488 cc and has a nominal gasoline power of 12 ps at 3000 rpm, which is 8.8 kW. Giorgio improved the CR a bit by replacing the head gasket, so probably this old engine would reach these values without problems, well, running on charcoal gas it would definitely reach at least half the rated power, but I believe the power could also be 5kW. Such a generator from an asynchronous motor with a nominal power of 5kW can produce approx. 4 - 4.5 kW of power after three phases, but more than 2kW per phase (electric chainsaw 2.4 kW works at full power),ā€¦ Older welding machine of the classic design, connected to such a generator, represents a rather large additional inductive load, so that it is not possible to weld on one phase (which requires at least 2-3 kW of power, but it is good to have 4 kW available), but if we use two phases, but it can be welded nicely, I tested this on a similar generator.

To summarize some information:

  • engine with a working volume of 500 cc achieves a power of 5 kW at 3000 rpm on wood gas (charcoal gas)
  • an asynchronous electric motor with a power of 5 kW - 3000 rpm needs a 3 x 50-60 uF capacitor for excitation and thus produces a power of 4 - 4.5 kW
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ā€¦indeed the chainsaw runs strongā€¦oak wood

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the first bcs mower from 1945

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found a voltmeter ā€¦can be useful for the generator

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Test it for accuracy. There is usually a way to adjust it.

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Thatā€™s a beautiful meter movement. Itā€™s a bit higher than I prefer for generator voltage. Several times in my life, I became the shortest path to ground for 120 vac. I have not gotten used to it yet. Iā€™m happy to live where 120 volts is the highest Iā€™m likely to, umm, experience. Maybe the rare 240 volt appliance. Iā€™m a big fan of 24 vdc, since I donā€™t conduct very well at that voltage :slightly_smiling_face:

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the voltmeter goes up to 500 volt because of the welder, what needs 380 voltā€¦all other tools have 220 volt hereā€¦ my electricity mentor tone have explained to me, i can regulate the motor 20 volts higher as the tool requires, than , under load goes downā€¦he has a lot of experience with such asynchronous motors for generator useā€¦
a electric strike with this tension is deadly, i must be carefulā€¦otherwise one chargasser less in the world, there are not so muchā€¦

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yesterday on the red bear mower during work the clutch not separated more motor and gearsā€¦
interessant clutch construction with a lot of discs- friction surfaceā€¦after cleaning , rust and dust and giving some oil on the clutch fork bearings, it works well againā€¦
our driveway is actually full with high grass and must be cutted, 2 km long -test
mowing on chargas is every year fine againā€¦

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I was always told itā€™s not the volts that kill you but the amps.

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Itā€™s the voltā€™s that pushes the ampā€™s through your body :slightly_smiling_face:

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the mower got new cutting knives, in tractor quality, 3 mm thick instead of 2mmā€¦

but the weather isnt good yet for cutting more grass, so we tried a welder, what has had a burnt primary winding, recently repairedā€¦and it works again.
we have found in the "collection " on a trafo the same kind of wire, 1,3 mm thickā€¦
should the "new " windings be threatened with paint for glueing together??


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the honda generator gx 200 on chargas with 1,5mm elektrodesā€¦(switched on 1)
thicker elektrodes i think the generator is not able to handle

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You are amazing Giorgio, rewinding transformers is no childs-play :+1:
I would ā€œslab onā€ some good epoxi varnish, it helps keep the windings steady.
The windings actually move some when using transformers like this, magnetic force, when moving they tend to rub of the enamel on the wires, wich leads to short circuit.

The best way for varnishing coils like this is to put them in a vacuum chamber, to get as much air out as possible between wires, and soak them in varnish under vacuum.
But not necessary for your welding transformer, as itā€™s pretty thick wires, and not so high voltage.

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I didnā€™t think paint will work that well

Usually the wire is coated with a polymer plastic, but they used shellac for decades.

For gluing the wires to together, usually they use i think wax, but the process is called ā€œpottingā€, because you stick it in a pot and let it soak in between the wires.

Potting isnā€™t strictly necessary for operation. It just helps prevents the vibration which work hardens the wire and makes it brittle, then it gets microfractures and which increases Resistance so it gets hotter then the varnish melts and the coil shorts. So basically it lasts longer. :slight_smile:

And on that note, you might have been able to reuse the old wire, anneal it by heating it and recoating it.

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