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Ignoramus7898

On 2015-04-14, wrote:
I bought my Bridgeport mill new in 1981. Today I just finished power
tapping a bunch of 5/16-18 through holes in .5 thick 7075 aluminum.
With the mill in low range at 250 RPM. I just put the tap in the drill
chuck, turn the spindle on forward till the tap is through and then
plug reverse the motor and back the tap out. I can't even begin to
count how many holes I have tapped this way on this machine. I have
never overheated the motor or switch gear and they are still original.
The motor has the "tropical insulation" in it so I guess that means it
can stand hot humid running. I don't know if a new Bridgeport today
would hold up as well, I hope they would. I do know of more than one
import mill that has cooked a motor and/or the switch gear.

I came across a pallet of five burned Excello motors.

Eric