(ET) $15.00 chainsaw....

[Chris Zach <czach computer org>]

Ok, in a new quest to make things work with the Elec-trak, I've started 
with a portable chainsaw.

Ryobi made a line of 18 volt appliances that run on little battery 
packs. One of the failures apparently was a cordless chainsaw. It's a 
really attractive device, with a chain, oiler, and a 10 inch length. 
There are *hundreds* of them being auctioned on Ebay right now, all new, 
all with the little oil containers un-opened. My guess is Ryobi made 
them and is now getting rid of inventory.

So I bought one. $15.00 without battery, can't beat that. It's really 
nice actually: Small and red and actually cute. It's plastic, but seems 
to be rather well made with modern features. It's also very light, which 
is nice.

I admired it for about 5 minutes, then took it apart. Screws, it's easy 
to take apart. The motor is a little thing with a geardown for the 
blade. Bar and chain of fine quality with a little anti-kickback shield.

Inside it's 16 gauge wiring, small but there. I have to look up the 
specs on the battey pack, my guess is it's a 3ah pack and they run it at 
around 12-15 amps. So it's an under 200 watt motor.

So I pulled out the little battery connector, and replaced it with a 
nice AMP plug. Attached another plug to a 14 gauge 50 foot extension 
cord and wired it into the rear 3 batteries on my Elec-trak. Off we went.

Oh the chain spins slowly at 18 volts. Must be the gearing and the fact 
that the pack had to be small. I see why these didn't do too well in the 
world. But we have Elec-Traks, so I went up to 24 volts.

Better, but still slower than my 14 inch electric. I wonder how it would 
work at a full 36 volts; I hate the thought of imbalancing my pack.

Still, it cut down a small tree without much difficulty. Just takes a 
bit of time. I'll try wiring it up for 36 volts and see how it works 
later, from what I remember you can run DC motors at higher voltage 
without wrecking them as the amps stay the same. Correct?

Only issue there would be the switch: It would have to clear a lot more 
voltage and might melt down. I recall that the Elec-trak chainsaw used a 
contactor in the line that was triggered by the saw switch. Makes sense.

It's a bit of a throwaway, but still I am thinking that instead of 
buying an AC inverter I could build a 36-24 volt DC-DC converter and get 
a few of these tools from Ebay.

Chris