A bird plucker/cleaner upper you mount on a drill.

You'll need small rubber plucking fingers.
I bought mine from the Ukraine, who knew ?
The plucker takes 18 and they come in packs of 20 :-)
http://www.ebay.co.uk/itm/20-pcs-pack-poultry-plucking-fingers-for-small-birds-small-poultry-/201114459605?pt=LH_DefaultDomain_0&hash=item2ed35b1dd5]

We found that while you can use this to totally pluck a bird. It's easier to do the quick big stuff by hand and then use the plucker to clean up the bird and get rid of the hard to remove down.
That and when we used it on a fully plumed bird it apparently looked like we were standing in the midst of a large snowstorm :-)

I also made a model that used the big 10cm plucking fingers. We found it actually went through the skin and started to remove the flesh. So that's not really useful.
If anyone wants the file for that let me know. I won't upload it otherwise as it's just bloody dangerous :-)

17/08/2016
Added heavy duty model.
made the base 4mm thicker, made the inside washer slightly larger and added reinforcement at the corners.