Running garden tools on 40-60V DC instead of 120VAC?

On 5/25/21 3:11 PM, Ralph Mowery wrote:
> In article <ih5887FniirU1@mid.individual.net>,
> news@analogconsultants.com says...
>>   I *miss* gas powered tools (string trimmer, edger, hedge trimmer, power
>>> washer, chain saw, etc.) as they always had plenty of "oompf".&#4294967295; But, the
>>> fuel (esp "mixed") was a PITA to keep on hand -- and wonder if I had to mix
>>> up more for today's workload).
>>>
>>
>> The only way to keep that stuff going somewhat reliably is to make 110%
>> sure the carburetor is dry after use, drain all fuel _and_ have Sta-Bil
>> in the fuel.
>>
>>
> 
> I switched to the ethanol free fuel a few years back and have no
> problems with the small engines.  I even put the Sta-bil in it just to
> be sure.  The lawn mower is put up from about november to march with the
> gas in it and for the last 10 years no problem.
> 

Fuel without ethanol is hard to find around here (east of Sacramento).


> I have a 5 kw generator that gets almost no use.  I have had to clean
> out the carborator about 3 times because of the ethanol junk.  I have
> learned to use the ethanol free gas and also drain all the fuel out and
> run it dry after each use.  Bought a propane/gasolien fuel generator
> about 2 years ago and only use propane in it.
> 

I use the regular ethanol gas but run the generator at least every two 
months, usually for 10-15 mins in non-eco mode.


> For those that like to use the 120 volt tools there is a small (about
> 500 to 700 watt) generator that runs on propane.  While you do have to
> contend with a drop cord, you can get by with one only about 25 feet
> long or less.  I have a gasoliene only one from Harbor Freight that is
> about the same size.  I carry that one near where I want to use the AC
> tools.  If not too far,just carry it, if longe, sit it in the small
> wagon and use the lawn tractor to pull it where needed.  It is sore of
> hard to start, but I use the spry starting fluid on it and it cranks
> right up.  I don't like to run the 2 cycle stuff dry so I use the E-free
> gas and Sta-bil in it and start it once a month.  It does put out a lot
> of smoke for a short period of time,but keeps the bugs away..
> 

Mine is an inverter generator and it needs about 3-4 pulls on average 
after sitting for more than a month. It's a 2kW briefcase style unit and 
I use a dolly to schlepp it around because my lower back isn't good. 
However, our property is so rocky and sloped that it's just not a 
practical method. I also sometimes cut stuff in neighbor lots for fire 
safety because they simply do not seem to care and let stuff get out of 
hand. Much easier to walk in there with a battery in a backpack. And you 
really don't want a gas-powered tool in a thicket of grease brush. That 
stuff is like a powder keg.

-- 
Regards, Joerg

http://www.analogconsultants.com/

On 5/25/2021 2:24 PM, Joerg wrote:
> On 5/25/21 1:28 PM, Don Y wrote:
>> On 5/25/2021 10:59 AM, Joerg wrote:
>>> On 5/24/21 8:01 PM, Don Y wrote:
>>>> On 5/24/2021 4:59 PM, Lasse Langwadt Christensen wrote:
>>>>> tirsdag den 25. maj 2021 kl. 01.02.09 UTC+2 skrev Joerg:
>>>>>> I dread all those extension cords when using the hedge trimmer and other
>>>>>> stuff. I found that if I connect the E-bike battery of a friend to it
>>>>>> the hedge trimmer runs somewhat slower but reliably. It had 53V DC.
>>>>>>
>>>>>> Those machines contain brush-type universal motors, probably with a
>>>>>> compensation winding but not sure. Is is safe to run these with 40-60V
>>>>>> DC over long periods of time or is there some sort of motor pathology
>>>>>> that could hit?
>>>>>>
>>>>>> If ok I could build a stack of 12-15 Li-Ion 18650 cells which, at 1.5A
>>>>>> to 2A, should afford me about 45min of runtime. Or maybe build three
>>>>>> sets of 4S or 5S batteries I could use for other stuff and then connect
>>>>>> those in series when bushes need to be trimmed 2-3 times per year. With
>>>>>> reverse-polarity protection diodes, of course, so I won't fry their
>>>>>> individual BMS'es.
>>>>>
>>>>> bite the bullet and buy a battery trimmer that runs on the same type of 
>>>>> battery as your other tools
>>>>
>>>> +1
>>>>
>>>> You're going to spend as much time and money trying to make a battery...
>>>> a commodity product that you can buy COTS mated to a specific trimmer.
>>>
>>> I'll have to make those batteries anyhow for ham radio activities (SOTA or 
>>> summits on the air). Got an old iWorx weed trimmer that has shot 18V NiCd 
>>> batteries. I want to rework those into 16V (4S) Li-Ion, taking a slight 
>>> power hit, and with a very small linear post regulator also use them for 
>>> portable radio gear in the field. Now if I could use three of these in 
>>> series to drive my other 120VAC garden tools that would be sweet. I've tried 
>>> and it works, just not sure if that's ok for the motors longterm.
>>
>> And this is a better use of your time than buying a ready-made solution?
>> I try to only spend time rolling-my-own when I can't find anything
>> remotely suitable (e.g., electric wheelbarrow)
> 
> I am mostly retired and ham radio is one of my hobbies. So time investment is 
> by different metrics just like it is when I spend an average of 5h to brew five 
> gallons of beer. As I said, this is going to be a set of batteries that will 
> serve at least three purposes. Plus likely serve during a power outage.

I'm old enough that I guard how my time gets used *jealously*.
Ignoring the obvious, there's also the potential for being
"distracted" by illnesses or even losing "capabilities" to
them.  So, I'm not keen on spending time when money is far more
plentiful!

>>>>> or something like this, 
>>>>> https://www.amazon.com/Rockpals-250-Watt-Generator-Rechargeable-Emergency/dp/B075SSMR6K/6 
>>>>
>>>> Personally, I prefer long cords as they can meet many needs and
>>>> eliminate the need for batteries (that fail and might not have
>>>> sufficient charge for the work you've set out to do, TODAY!)
>>>
>>> You probably don't have a property with steep rocky slopes and lots of 
>>> prickly agave plants that latch on to extension cords like shark teeth.
>>
>> No, we have a property littered with "landscape boulders" (large rocks that
>> you pay to have delivered and placed on your land -- where they will never
>> move!) and ~100 "plantings".  The rocks very aptly bite into the cords
>> as they pass, the larger plantings defy the cord taking the best
>> "straight line between two points" and the smaller plantings are
>> inevitably damaged if the cord passes by or over them (my cords are
>> 12/3, 5/8" dia)
> 
> Then why cords?

Ever try to dig in caliche?  It's much easier to rent a BIG electric breaker
and shovel attachment.  Or, drilling through the concrete block wall (or
its footer) to pass a pipe through.  Etc.

>> OTOH, I know I can get to any place outside or inside the house (e.g.,
>> site the genset out in the back yard and run 100' cords into the house
>> to keep the furnace running, refrigerator, freezer, etc.) and, barring
>> an outage (which would then require the use of the genset), knowing
>> that I can spend as long as I want trimming, cutting, washing, etc.
>>
>> It's much easier to drag an electric power washer up onto the roof
>> than to also have to drag up "enough battery" to keep it running for
>> an hour (no, I don't want to stop once I've started!).
> 
> With bush trimming it's different here. I have to clean up between cutting 
> phases, snip here and there with the lopper, et cetera. Plenty of time to 
> recharge. Most of the time other stuff such as the pool needs attention as well 
> so I never run out of work out there. It's a matter of planning.
> 
>> And, I never have to worry about dead (or flat) batteries.  I have
>> enough of them *in* the house running the 18 UPSs -- and they earn
>> their keep *daily*!  Though everything in my bug-out-bag is
>> deliberately 12V powered so I can carry a battery pack and
>> use it for any device -- assuming I don't have the vehicle's battery
>> available to me (e.g., if we had to hike out).
> 
> No UPS here, don't need that. At least not anymore.

Each computer, here, has its own UPS.  We rarely have outages
(when we *do*, the noise is almost deafening as each UPS starts
to complain).  They are very handy for "glitches" (it seems
there must be some sort of mains switching event that happens
every night in the wee hours as the lights will flicker and I'll
hear all of the UPSs hiccup).

The outages we've had have been a result of equipment
failures -- our services are below grade and the cables
have reached/exceeded their service life (esp in light
of the increased loads that have developed over the decades)

So, *we* might lose power while the folks immediately
behind us are unaffected -- or, the next block north
or south.

>>>> as well as keeping fuel on hand (for gas powered devices).
>>>
>>> And then it won't start, carburetor gunked up because of the #%^&@!! 
>>> California gas. Plus if those run, you are breathing in 2-cycle exhaust for 
>>> hours which can't be healthy. That's what I definitely don't want anymore.
>>
>> I *miss* gas powered tools (string trimmer, edger, hedge trimmer, power
>> washer, chain saw, etc.) as they always had plenty of "oompf".  But, the
>> fuel (esp "mixed") was a PITA to keep on hand -- and wonder if I had to mix
>> up more for today's workload).
> 
> The only way to keep that stuff going somewhat reliably is to make 110% sure 
> the carburetor is dry after use, drain all fuel _and_ have Sta-Bil in the fuel.

When I was younger, I had to deal with grass -- which had to be mowed
at least weekly.  Or snow.  So, keeping fuel on hand was necessary.
But, it was a safety concern and messy.  And, you always had to
worry about getting some "crappy gas" (e.g., water from bottom
of the tank at the filling station)

>> [I felled a couple of 18" dia trees with the neighbor's *electric* chain saw.
>> Felt like I was digging a ditch with a tablespoon!  :< ]
> 
> 18" diameter is a bit much for an electric saw.

Short bar -- but, you can cut *around* the tree instead of across it.
(not as safe but no problem if you know what you're doing).

>>>> Battery powered power-washer?  Jackhammer?  Air compressor?
>>>
>>> Except for the jackhammer they make those. Too wimpy for me though.
>>
>> A 20A outlet can do a lot of "work" for you -- and for an indefinite
>> amount of time.
> 
> If you have one nearby. At a lot of place on our property that's just not the 
> case.

Just use a longer cord!  With 12AWG cords, you can go a pretty long
way before you start having to worry about losses in the cord.

> Main thing is, I like to be able to go out there and quickly do a couple bushes 
> that look "unkempt", then do something else.

We trim twice a year -- when we are told the city's "Brush and Bulky"
pickup is coming.  This allows us to simply drag the materials to
the front curb and let the city folks haul them away (we separate
items so things like yard waste can be shredded on the spot and
the chips hauled off to mulch city plantings).

On 5/25/2021 3:11 PM, Ralph Mowery wrote:

> I switched to the ethanol free fuel a few years back and have no
> problems with the small engines.

Hmmm... that's interesting.  But, would mean keeping that fuel in
a separate container (instead of "in the car")

> I even put the Sta-bil in it just to
> be sure.  The lawn mower is put up from about november to march with the
> gas in it and for the last 10 years no problem.
> 
> I have a 5 kw generator that gets almost no use.  I have had to clean
> out the carborator about 3 times because of the ethanol junk.  I have
> learned to use the ethanol free gas and also drain all the fuel out and
> run it dry after each use.

That;s our strategy.  You can still *use* the electricity
that it is generating while running dry -- it's just more
costly than the electric power that has just been "restored".
And, it gives the engine a chance to actually *run* instead
of sit around waiting for the opportunity.

> Bought a propane/gasolien fuel generator
> about 2 years ago and only use propane in it.

We thought of buying a small one (2KW portable) that we could
transport without having to worry about liquid fuel leaking
inside the car.

We figured we could leverage the propane for the grill
as an on-hand supply.  And, if "small", it shouldn't
burn through that supply as quickly as it would if having
to support bigger loads.

[The LAST thing we want to do is have to run out to buy
fuel during an outage]

> For those that like to use the 120 volt tools there is a small (about
> 500 to 700 watt) generator that runs on propane.  While you do have to
> contend with a drop cord, you can get by with one only about 25 feet
> long or less.  I have a gasoliene only one from Harbor Freight that is
> about the same size.  I carry that one near where I want to use the AC
> tools.  If not too far,just carry it, if longe, sit it in the small
> wagon and use the lawn tractor to pull it where needed.  It is sore of
> hard to start, but I use the spry starting fluid on it and it cranks
> right up.  I don't like to run the 2 cycle stuff dry so I use the E-free
> gas and Sta-bil in it and start it once a month.  It does put out a lot
> of smoke for a short period of time,but keeps the bugs away..

On 5/25/2021 2:21 PM, Ralph Mowery wrote:
> In article <s8jmkp$f84$1@dont-email.me>, blockedofcourse@foo.invalid
> says...
>> No, we have a property littered with "landscape boulders" (large rocks that
>> you pay to have delivered and placed on your land -- where they will never
>> move!) and ~100 "plantings".  The rocks very aptly bite into the cords
>> as they pass, the larger plantings defy the cord taking the best
>> "straight line between two points" and the smaller plantings are
>> inevitably damaged if the cord passes by or over them (my cords are
>> 12/3, 5/8" dia)
> 
> You will not like it, but around some items I use Roundup or other grass
> and weed killer.

We have no "lawn" so the number of weeds is easily controlled
just by pulling them when they first sprout.  (We used RoundUp
decades ago to kill off the original "lawn".)

> I have never tried it,but there are lots of you mix
> your own out of kitchen items like viniger that is not harmful to you
> unless you decide to drink large quanities.

Yeah, a neighbor is always trying to convince folks, here, to
use such a mix.  ("chemicals" are BIG, here; ground water
supply is rarely considered when folks start spraying their
"weeds")

On 26/05/2021 04:14, Joerg wrote:
> On 5/25/21 4:41 AM, Chris Jones wrote:
>> On 25/05/2021 09:02, Joerg wrote:
>>> I dread all those extension cords when using the hedge trimmer and 
>>> other stuff. I found that if I connect the E-bike battery of a friend 
>>> to it the hedge trimmer runs somewhat slower but reliably. It had 53V 
>>> DC.
>>>
>>> Those machines contain brush-type universal motors, probably with a 
>>> compensation winding but not sure. Is is safe to run these with 
>>> 40-60V DC over long periods of time or is there some sort of motor 
>>> pathology that could hit?
>>
>> If you go much higher in voltage using DC on equipment designed for 
>> AC, then the on/off switch may arc for quite a while each time you 
>> turn it off, especially with an inductive field coil in series, and 
>> even more so at higher currents, like if you stall the motor and 
>> really want to turn it off. Same applies to fuses, if it has any. 
>> Perhaps 53V is still ok. Otherwise, a device that makes the current go 
>> to zero periodically (like an inverter) might help to extinguish any arc.
>>
> 
> Good point. Might have to add in a TVS across the motor connection.
But if you do that, label it and change the mains connector to something 
else, in case someone plugs it into a wall socket!

On 26/05/2021 04:07, Joerg wrote:
> 
> Edison failed to make cars

I've seen pictures of some electric cars from >100 years ago, with 
Edison NiFe batteries in them. IIRC some were still working, as those 
batteries are quite robust.

In article <s8k313$ofq$1@dont-email.me>, blockedofcourse@foo.invalid 
says...
> 
> > Bought a propane/gasolien fuel generator
> > about 2 years ago and only use propane in it.
> 
> We thought of buying a small one (2KW portable) that we could
> transport without having to worry about liquid fuel leaking
> inside the car.
> 
> We figured we could leverage the propane for the grill
> as an on-hand supply.  And, if "small", it shouldn't
> burn through that supply as quickly as it would if having
> to support bigger loads.
> 
> [The LAST thing we want to do is have to run out to buy
> fuel during an outage]
> 
> 

I think the 5 kw gas generators are about right for most people unless 
going with the inverter type generators.  Go much larger and you burn a 
lot of fuel even if not using much power.  

I caught a 3500 watt dual fuel generator on sale so bought it .  The 
book says it will run  5 to 8 hours on a 20 lb propane tank depending on 
the load.  Good thing about the propane is that the fuel never goes bad 
or gums up the carborator.  Also there are lots of places like the Blue 
Rino where you can swap out the tanks.  However they often only have 15 
pounds in the tank instead of the 20 lb it can hold.  I don't have a gas 
grill, but for those that do you have a reserve for either activity.  I 
did buy 2 tanks of propane and thinking about buying 2 more.  Around 
here it is about $ 12 to fill them and the tanks are about $ 35 empty.

I am not sure which is really safer to store,but I have a small building 
about 50 feet  away from the house that I store the fuel in, from 5 to 
18 gallons of gas and a propane tank. The other tank stays connected to 
the generator that is in a 'dog house' next to the house where it is 
plugged in when needed.  I do keep a gallon can of mixed fuel for the 2 
cycle engines in a seperate carport type garage that has my truck and 
lawn tractor and weedeater and leaf blower.

Chris Jones <lugnut808@spam.yahoo.com> wrote:
> On 26/05/2021 04:14, Joerg wrote:
>> On 5/25/21 4:41 AM, Chris Jones wrote:
>>> On 25/05/2021 09:02, Joerg wrote:
>>>> I dread all those extension cords when using the hedge trimmer and 
>>>> other stuff. I found that if I connect the E-bike battery of a friend 
>>>> to it the hedge trimmer runs somewhat slower but reliably. It had 53V 
>>>> DC.
>>>>
>>>> Those machines contain brush-type universal motors, probably with a 
>>>> compensation winding but not sure. Is is safe to run these with 
>>>> 40-60V DC over long periods of time or is there some sort of motor 
>>>> pathology that could hit?
>>>
>>> If you go much higher in voltage using DC on equipment designed for 
>>> AC, then the on/off switch may arc for quite a while each time you 
>>> turn it off, especially with an inductive field coil in series, and 
>>> even more so at higher currents, like if you stall the motor and 
>>> really want to turn it off. Same applies to fuses, if it has any. 
>>> Perhaps 53V is still ok. Otherwise, a device that makes the current go 
>>> to zero periodically (like an inverter) might help to extinguish any arc.
>>>
>> 
>> Good point. Might have to add in a TVS across the motor connection.
> But if you do that, label it and change the mains connector to something 
> else, in case someone plugs it into a wall socket!

Or just leave it alone. It sounds like this guy can fix a switch if he has 
to.

On 5/25/21 8:08 PM, Chris Jones wrote:
> On 26/05/2021 04:14, Joerg wrote:
>> On 5/25/21 4:41 AM, Chris Jones wrote:
>>> On 25/05/2021 09:02, Joerg wrote:
>>>> I dread all those extension cords when using the hedge trimmer and 
>>>> other stuff. I found that if I connect the E-bike battery of a 
>>>> friend to it the hedge trimmer runs somewhat slower but reliably. It 
>>>> had 53V DC.
>>>>
>>>> Those machines contain brush-type universal motors, probably with a 
>>>> compensation winding but not sure. Is is safe to run these with 
>>>> 40-60V DC over long periods of time or is there some sort of motor 
>>>> pathology that could hit?
>>>
>>> If you go much higher in voltage using DC on equipment designed for 
>>> AC, then the on/off switch may arc for quite a while each time you 
>>> turn it off, especially with an inductive field coil in series, and 
>>> even more so at higher currents, like if you stall the motor and 
>>> really want to turn it off. Same applies to fuses, if it has any. 
>>> Perhaps 53V is still ok. Otherwise, a device that makes the current 
>>> go to zero periodically (like an inverter) might help to extinguish 
>>> any arc.
>>>
>>
>> Good point. Might have to add in a TVS across the motor connection.
> But if you do that, label it and change the mains connector to something 
> else, in case someone plugs it into a wall socket!


Just use a large enough TVS so it's ok on 120VAC. The switch must be 
rated to take sparks in the 200-300V range. On DC it'll arc a bit longer 
but I am not one of those guys who is constantly clicking the trigger. 
Like the guy in a neighbor yard yesterday who constantly revved his gas 
chain saw. Its clucth can't last long that way.

-- 
Regards, Joerg

http://www.analogconsultants.com/

On 5/26/21 7:19 AM, Ralph Mowery wrote:
> In article <s8k313$ofq$1@dont-email.me>, blockedofcourse@foo.invalid
> says...
>>
>>> Bought a propane/gasolien fuel generator
>>> about 2 years ago and only use propane in it.
>>
>> We thought of buying a small one (2KW portable) that we could
>> transport without having to worry about liquid fuel leaking
>> inside the car.
>>
>> We figured we could leverage the propane for the grill
>> as an on-hand supply. 


Real men do not use gas to grill :-)

No kidding, I generally use real wood. Mostly Almond and Manzanita.


>>                       ... And, if "small", it shouldn't
>> burn through that supply as quickly as it would if having
>> to support bigger loads.
>>
>> [The LAST thing we want to do is have to run out to buy
>> fuel during an outage]
>>

That's one reason why we have a gas generator, not propane. You can buy 
a squeeze pump from Harborfreight for under $10 and that plus a small 
extra section of clear fuel hose allows to siphon off gas from your car. 
Provided one fills up before a potential emergency a car gas tank stores 
much more energy than a barbecue cylinder.

Come to think of it, I wonder if a Tesla can be used to generate a kW or 
so of 120VAC to run a frigde plus some little things.

> 
> I think the 5 kw gas generators are about right for most people unless
> going with the inverter type generators.  Go much larger and you burn a
> lot of fuel even if not using much power.
> 
> I caught a 3500 watt dual fuel generator on sale so bought it .  The
> book says it will run  5 to 8 hours on a 20 lb propane tank depending on
> the load.  Good thing about the propane is that the fuel never goes bad
> or gums up the carborator.  Also there are lots of places like the Blue
> Rino where you can swap out the tanks.


Unless those places can't because the utility has called in yet another 
"PSPS" outage.

[...]

-- 
Regards, Joerg

http://www.analogconsultants.com/