Battery saws and big wood

[Old2stroke]

I have a friend that has a lot of big tree storm damage and as he has issues with gas chainsaws, he is thinking of a good battery powered one. Are there electric saws available that would handle a 20" bar in hardwood and what voltage would be required? How about cutting time on one battery? What happens to an electric saw when you overload it and drag the chain speed way down?

 

[HumBurner]

"What happens to an electric saw when you overload it and drag the chain speed way down?"

The chain stops moving. Sometimes it'll take a second or two for the chain to be able to move again.

 

[ElevatorGuy]

20” in hardwood is 60cc territory, I wouldn’t go battery.

 

[isawben]

Get one that can handle a 14-16 in bar, and make multiple cuts.

 

[SteveH]

I have a battery saw and am using it regularly now, along with a 441 and 026. The battery saw is being used as much as the two gas saws together.

Mine has an 18" bar. I am cutting up 9-12" trunks at present. I can run about 40 minutes or so on one battery [80 v, 4 amp hr]

Just for the heck of it, I tried cutting a 24" trunk the other day, blue spruce. It was green, a wind-downed tree. I was able to get about a quarter of the way through the cut [cutting rounds] and the saw lagged a bit and I quit, have the 441 for that. I just wanted to see what the battery saw would do.

So, my experience with the battery saw is good performance up to about 14" diameter and nearly 3/4 hour per charge. I do have three batteries, so I can switch out if needed. Charge time is about an hour and a half on the 4 amp hr. I also have a 2 amp hr battery and that takes just over a half hour to charge [also 80 volts].

Like with any saw, sharp chain is the way to go. I find the battery saw needs the sharp chain even more than the gas saws. Don't know why.....

 

[ValleyForge]

Coal fired saws are a novelty….

 

[Franny K]

say the charger is 500 watts
say 13 amps at 120 volts will get you 2 hp in a circular saw
13*120=1560 watts

so, to get 2 hp it will need to charge for three times as long as to run. you probably would like 4 hp maybe could settle for 3 hp on a narrow kerf chain. Modify the above equation as needed maybe the charger is only 300 watts. I do not believe run time posted on the internet. 800 seconds or 13 minutes and not totally constant was what I got for my t536 Husqvarna and the 4.2 amp hour battery. If it is hot and the chainsaw you select does not adequately cool both the battery and the motor it will cut out earlier than in the spring or fall is my experience with the Makita stuff that only cools the battery on the charger. Basically these things for the brushless motors cut out like a circuit breaker trips, can let off and go. The brushed ones can be pushed harder and act more like a corded too.

Wait would be my suggestion but have not any of the larger heavier newest models. Makita is supposedly coming out with an 80 volt. When some come out with a small spline drive and cooling on the battery and saw I will perhaps upgrade.

Fran

 

[Franny K]

Coal fired saws are a novelty….

You are just being silly. Maybe you do have a coal fired plant nearby, even still the high pressure steam and turbine generation transmission charging losses will still come out more environmentally "responsible" than a two cycle engine.

 

[ValleyForge]

You are just being silly. Maybe you do have a coal fired plant nearby, even still the high pressure steam and turbine generation transmission charging losses will still come out more environmentally "responsible" than a two cycle engine.

I agree, it would be more efficient to just burn the coal in the saw….

I’ll stick with the more environmentally responsible option…..

 

[ericm979]

I find the battery saw needs the sharp chain even more than the gas saws. Don't know why.....

Battery saws usually run a narrower chain.

 

[JustPlainJeff]

I think the key words in your description OP were "A LOT OF BIG TREE STORM DAMAGE". I don't know what your definition of "a lot" is, but as soon as I heard that, I mentally eliminated a battery powered option in my own head. I think the battery powered saws have their place, but it's not in big lumber, and unless you want to invest in multiple batteries, which can get expensive in a hurry, it sounds like that job would take FOREVER to finish with a battery powered saw. Shoot, even with multiple batteries, the battery powered saws, just don't turn nearly as fast as a gas powered saw, so I think it would still take way longer than I would consider doing with a battery powered saw. To each their own though. Maybe you can go help him?

 

[GrizG]

Stihl has some corded electric saws... MSE 210 is 15 AMP which from a practical standpoint comes in at nearly 2 HP. That would be a better option than the battery saws as you can keep running... That said, I've been cleaning up ice storm damage since April and have done so in 5-8 hour sessions with an MS261 and MS461. The trees have ranged from about 6" DBH to about 30" DBH. I cannot imagine trying it with a 2 HP saw... I might be tempted to turn it on myself!

 

[oldbuzzard]

I have a battery saw and am using it regularly now, along with a 441 and 026. The battery saw is being used as much as the two gas saws together.

Mine has an 18" bar. I am cutting up 9-12" trunks at present. I can run about 40 minutes or so on one battery [80 v, 4 amp hr]

Just for the heck of it, I tried cutting a 24" trunk the other day, blue spruce. It was green, a wind-downed tree. I was able to get about a quarter of the way through the cut [cutting rounds] and the saw lagged a bit and I quit, have the 441 for that. I just wanted to see what the battery saw would do.

So, my experience with the battery saw is good performance up to about 14" diameter and nearly 3/4 hour per charge. I do have three batteries, so I can switch out if needed. Charge time is about an hour and a half on the 4 amp hr. I also have a 2 amp hr battery and that takes just over a half hour to charge [also 80 volts].

Like with any saw, sharp chain is the way to go. I find the battery saw needs the sharp chain even more than the gas saws. Don't know why.....

What make battery saw?
I have a MSA220 and a 540xp with 16” bars. I like them both but would like an 18” bar.

 

[Philbert]

All this is covered in the many battery saw threads. Current models compete with 30 to 50cc saws. As with those gas saws, you can cut most anything, if you are patient. But they might not be the best choice for a big task.

Most battery saws have an overload cut out, in addition to a chain brake.

Don’t confuse voltage with power. 80V is not necessarily more powerful than 40V.

As @GrizG notes, I have cleaned storm damage with corded electric saws, one power was restored.

I have cut a full face cord of green, silver maple with one battery, but battery capacity varies (measured in Watt-Hours).

Philbert

 

[Mad Professor]

All this is covered in the many battery saw threads. Current models compete with 30 to 50cc saws. As with those gas saws, you can cut most anything, if you are patient. But they might not be the best choice for a big task.

Most battery saws have an overload cut out, in addition to a chain brake.

Don’t confuse voltage with power. 80V is not necessarily more powerful than 40V.

As @GrizG notes, I have cleaned storm damage with corded electric saws, one power was restored.

I have cut a full face cord of green, silver maple with one battery, but battery capacity varies (measured in Watt-Hours).

Philbert

Yes, from my high school physics class........... Power = V (volts) X I (amps)

 

[Kodiak Kid]

I have a battery saw and am using it regularly now, along with a 441 and 026. The battery saw is being used as much as the two gas saws together.

Mine has an 18" bar. I am cutting up 9-12" trunks at present. I can run about 40 minutes or so on one battery [80 v, 4 amp hr]

Just for the heck of it, I tried cutting a 24" trunk the other day, blue spruce. It was green, a wind-downed tree. I was able to get about a quarter of the way through the cut [cutting rounds] and the saw lagged a bit and I quit, have the 441 for that. I just wanted to see what the battery saw would do.

So, my experience with the battery saw is good performance up to about 14" diameter and nearly 3/4 hour per charge. I do have three batteries, so I can switch out if needed. Charge time is about an hour and a half on the 4 amp hr. I also have a 2 amp hr battery and that takes just over a half hour to charge [also 80 volts].

Like with any saw, sharp chain is the way to go. I find the battery saw needs the sharp chain even more than the gas saws. Don't know why.....

Every saw needs a sharp chain! Sharp is the standard! There is no such thing as dull when it comes to a saw chain! If it's dull? It's not a saw chain! It's a paper weight!

 

[Kodiak Kid]

I have a friend that has a lot of big tree storm damage and as he has issues with gas chainsaws, he is thinking of a good battery powered one. Are there electric saws available that would handle a 20" bar in hardwood and what voltage would be required? How about cutting time on one battery? What happens to an electric saw when you overload it and drag the chain speed way down?

Battery powered chain saw? I would try Toy's 'R' Us first!Probably find wut your looking for there. If not? My three year old daughter might lend you her's for some candy as saw rent!

Just take'n the piss out of ya a little bit bud! Sorry I couldn't help it!

Cut safe, stay sharp, be aware, and keep your battery charger at the ready!

 

[anlrolfe]

The brushed ones can be pushed harder and act more like a corded tool.

Brushed motors are archaic. The brushes add resistance. Whether you can see brush arcing or not, it's consuming power, robbing it from the motor, making more heat, and killing your run time. Most quality batteries, ie Milwaukee, have onboard power management to prevent overloading and as previous mentioned "cut out" when that threshold is exceeded. That's saving your $$$ investment.

Yes, from my high school physics class........... Power = V (volts) X I (amps)

For a motor load it's actually
Power = V x I x PF
PF(power factor) = the phase shift created in a reactive circuit AKA motors inductive nature. PF is a ratio of true to apparent power. Simply, what is the load putting out/producing(HP) vs what is it demanding. A generic induction motor may have PF 75-85%.
Compounding these losses is Efficiency, so subtract heat loss in the motor and heat loss in the battery from internal resistance loss, commutation from brushes or transistors(brushless), windage, friction, flux linkage, eddy currents....
It's been a while since I've used the Milwaukee chainsaw but as I recall it's on par with my old 026, so maybe equate to 40-45cc gas.

Don’t confuse voltage with power. 80V is not necessarily more powerful than 40V.

I agree 100%
Getting higher voltage puts cells in series which increases internal resistance. If you double the voltage mathematically you can double the power BUT, current is the better part of power. P=I^2R squaring the current means that if you can double the current you produce 4x the power. Accidently feed your 120v load 240v and this is why the factory smoke comes out so fast. IMHO, Parallel the batteries(CELLS) and a lower voltage with more AMPs is the way to go for portable tools.

 

[Husky77]

I have a friend that has a lot of big tree storm damage and as he has issues with gas chainsaws, he is thinking of a good battery powered one. Are there electric saws available that would handle a 20" bar in hardwood and what voltage would be required? How about cutting time on one battery? What happens to an electric saw when you overload it and drag the chain speed way down?

What are the "issues" why I asked is a friend I knew was so scared of a saw it was an accident just waiting to happen. Never underestimate and think because a battery saw is quiet it cant do the same damage to flesh and bone. Or could it be just a two stroke engine he cant get his head around, again this could be an accident just waiting to happen. I see lots buying a saw thinking they can cut some wood without a thought, it's a brilliant tool in the right hands but the wrong hands can be deadly. One I knew didnt know what the chain oil was for.... thought it was a four stroke saw!

 

[J D]

Getting higher voltage puts cells in series which increases internal resistance. If you double the voltage mathematically you can double the power BUT, current is the better part of power. P=I^2R squaring the current means that if you can double the current you produce 4x the power.

The thing about that is, in order to increase the flow of current either the voltage needs to go up or the resistance needs to come down... & the more current passes the more every bit of resistance creates loss as heat. The sum of it (pun intended) is "Power (in Watts) = Volts x Current (in Amps)"... So changing either voltage or current will cause an equally proportional change in power. However, in the real world the resistance of the load is made up of all the connections, wiring, circuitry, & internal resistance of the batteries, & these resistances start to become rather significant in comparison to a motor with the low resistance needed to draw a higher current.
This is the same reasoning behind power being transmitted at high voltage over distance.
The problem with higher voltage in power tools lies more with the insulation & safety side of things