Thinking abut a cordless hedgetrimmer

well yes. My shoulders are aching from this afternoons efforts to chop up a 10 metre tall tree that fell over last year. The thickest part of the trunk - that I have yet to tackle - is about 2' diameter.

My little chainsaw - petrol - is having trouble with the 8" diameter sections. I guess its around 1500W equivalent.

I was on for about a continuous hour today 1.5kwh.

The equivalent battery model is twice the price and has little more than half an hour in the battery

and weighs only a little less.

No, not light years, about 50%, For the whole package. A neodymium based brushless motor is a lot lighter than an equivalent 2 stroke. But the final weight is really all about battery capacity. That means a cordless is a winner for occasional consumer use, but is f****ng pointless if you need to run the thing all day on a major bit of tree surgery

They do, but the price you pay is very short charge life. and its not a lot lighter.

A decent bowsaw would have no trouble at all with such diameters, unless the wood is yew or hawthorn, when anything would. Yes, it would take some time and effort.

Regards, Nick Maclaren.

given something like a total of 500 meters of hedge I never considered using anything else....:-)

Oh sure. When the last chainsaw died I used the bowsaw on similar, this is 5-10 times faster. And I am getting too old

Nothing specially tough about hawthorn, This is field maple. Tougher than hawthorn IME. Last hawthorn I cut up the small Stihl waltzed through.

maple similar to oak and yew but cant find specs for hawthorn on line... oh..they reckon 2x hard - well I didnt find it so

What I meant was that its taking a long time to cut the tree. Its purely a function of power, but then a more powerful saw would weigh even more.

I can probably do about 100W bow sawing. Chainsaw does 1500W.

Good grief! Not on your Nelly! If I want exercise I'll walk to the fridge for another beer.

Bill

That doesn't equate with a vehicle's range with a tankful of petrol compared to a battery full of leccy. And the battery weighs a lot more than the petrol.

Bill

My 36V chainsaw (with a nice new blade) happily slices 14" willow trunks, it says it's 1100W max.

Don't give up.

There are differences between the original chain, and some third party replacements. I found my saw worked better with the second chain on it. I would never have guessed there would be a difference, as visually "a chain is a chain", right ?

Paul

yes. That sounds about right. First of all this is maple. Its hard stuff. More than that its been fallen all over winter and has dried out. Finally 'having trouble' mean its slow...oh the chips are flying out all right, but each cut takes a minute, not 5 seconds like smaller stuff.

And can your cordless keep that up for two or three hours to section a full sized tree?

I'll give the blade a sharpen and see if I can get near to finishing the job today. Then it's on to easier stuff. 5m yews and Hornbeams that haven't been lopped in 7 years...

actually it is the original chain as the saw its brand new, but it probably needs sharpening by now. So far its been brilliant, but really the saw is too small for what I will be asking it to do. The blade length is less than the trunk diameter...so the later cuts will be in two goes, one from each side..

no, its fairly close - leccy cars have about 200 miles range and petrol ones 400 - 600.

But its oranges and apples, What counts is the total package, and an electric power train weighs way less than a petrol or diesel one *if you exclude the battery*.

Mains powered hedgetrimmers ought to be the lightest per unit power, of all.

But the actual stats that I looked up on a Stihl,. showed that the battery equivalent to my baby Stihl was more expensive, of similar power, slightly less weight but only half an hour cutting time.

Operationally as with a car what counts is the recharge time - seldom less than an hour if you want the battery to last.

It takes me less than a minute to refill oil and petrol...

I only nip down and do a couple of hours worth at a time to get rid of the tree, the section of trunk was [guestimating] a few hundred kilos, so levering it about to avoid the saw touching the ground takes a lot of time, the saw's not running for long periods, but I'd expect it to need maybe a set of batteries per hour if it was.

I don't think people realise that the cross section area goes up as the

And that times the wood hardness (willow is soft) is the amount of energy it takes...

Not only do you have to recharge the battery more frequently, but every time you have to wait many hours, as opposed to 5 mins max when filling up with

When cars have enough range to do a whole journey on one charging of the battery, then they'll be a viable replacement. We'll probably never get anywhere near the recharge rate of 60 litres of diesel (700 miles range) in < 5 minutes, but then that is several MW of power. But if charging can be confined to overnight when you're not travelling (or 9-5 when you're in the office) then it's no great hassle. But having to charge during a journey is a definite disincentive to owning an electric car.

That, too, is my concern. If life returns to 'normal', I expect to do 2 or

Longer advertised mileage ones appear to be coming, but they seem to mostly "fashion statements" rather than useful vehicles.

its the same order of magnitude

Oh I agree. Don't get me wrong.

My point was really that while electric cars *are* close, there is certainly no cigar. Not even a hand rolled old Holborn.

Actually 5 minute recharges are *technically* possible. The trade-off is shorter battery life, less efficiency and a heavier battery. This is one area where development is actually making decent progress,

I didn't.

Two resharpens, four tanks of petrol, and almost 2 hours of continuous cutting.

Batteries may work for occasional hobby use, but some of us have MAN SIZED TREES.

Sharpening is te key. I need a new file now ...