Hair particle feathers: any advice?

I’m trying to add some down to soften the edges of this bird model, but am losing my mind trying to get it working. The theory, I thought, was pretty sound: take some short particle hair, clump the heck out of it to make “feathers”, then brush it fairly flat to the model’s surface, fluffing it up around the belly/chest area.

I’m not sure if that’s sound theory to start with, but the practice is a disaster.

I’m pretty new to Blender (and this is my first time playing with the particle system) but from all appearances, it seems to be more or less ignoring the clumping, styling, and length map settings when I render. It’s a massive, fluffy puffball.


For the experts out there: where am I going so wrong? Any idea why the clumping/styling seems to have so little effect? Is it a matter of scale? Or is there a better way to do this entirely? Any advice would be very appreciated!

Ah! Forgot: here are the density/length maps, if that helps:

I assumed shortening the particle wouldn’t “cut off” the end of each clump, but maybe that’s what’s happening?