Originally Posted by frewster

I decided to compare the A86BHM, on the left, to the A80BHSW, on the right. The A80 is shorter, both in case size and motor length. The gears are almost identical although the A80BHSW servo spline gear does not have a pin to keep it from rotating 360 degrees. The A86BHM has a pin and a a slot that keeps it from rotating more than about 220 degrees. The encoder for the A86 cannot rotate continuously but the one for the A80 can, of course.

The A80BHSW has the encoder and the motor held in with the same white epoxy as in Bill's, so that's another difference from the A86BHM.

The board is identical to the A86BHM but, like on Bill's, the codes on the FETs has been removed so I can't identify them.

The biggest difference I noticed was the pin for the center gear. It's 2.0mm in diameter for the A86BHM and only 1.6mm for the A80BHSW.

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