I'm using a 9 inch angle grinder to open the cases & also to remove one end of the windings.
It leaves the ends clean with no caught & ripped out bits of wire.
The small discs do cost a lot more than the 9inch ones, thats just taking money from away the job, the 9 inch discs vary a huge amount in prices, it pays to look around to get the best deal.
My 9inch grinders out of action at the moment, the 4 screws holding the discs shaft come loose & the two gears got a bit to far away from each & started to strip the teeth.
Thats some maintenance I should have done, my fault entirely.
With any luck I can pick the burrs free & maybe add a spacer so the gears are closer to each other.
It was a cheap brand new grinder when I got it, a 'cheapo' brand but its still a good worker.
So, check the 4 screws are tight every time you use one or replace a disc, I'm going to put in hex head screws & locking tabs.
The grinder makes the copper easyer to work with when removing the insulation & strings & the 3mm thick cut dosn't make much difference to the copper weight.
The other option I have found is similar to what you are doing with the sawzall.
Note, those sawzalls seem to be pretty common in the US. I have only seen one in NewZealand.
What I did was to use a cold chisel to cleave a gap between the laminations in the same place as you have cut thru it.
Then I open it up a bit more & then use a hand hacksaw or meat cleaver to cut thru the copper wiring.
It comes out of the laminations easyer too, but twice as many bits of plastic insulation to pick off....
I will put some effort into making a ornimental cannon from gas bottles & fridge compressors & post the info here as I think its a good sideline job to scrapmetal.
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