I'm not real familiar with felting, but I understand some colors of some yarns felt faster than others. I wonder if blocking after felting would help even things out. Sounds like a neat idea for a heavy blanket. Seems like it would be nice and warm.
"Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it's the only thing that ever has."--Margaret Mead
If you don't let it felt too much you should be able to make it even and not out of shape. I can't picture a felted blanket being soft enough, but that's probably just me. I do think it would make a great rug though!
Try "fulling" it instead of felting it completely.
The idea is to stop when some shrinkage has occurred but there is still some stitch definition.
The blanket will be warmer and thicker, but it will still feel like knitting. I agree with Jan: a hard, firm, fully-felted blanket just doesn't sound comfortable.
As for the different rates at which different colors felt, you may want to felt a swatch of each color and see what happens.
Funny you should post this. My mom found an old blanket some uncle had made years ago. It reminded me of the Hudson bay blanket. My mom said he knit it. It had to have been felted then.
If I ever see it again, I'll get a picture of it. It made me think of trying the same thing.
Please keep us posted on how it turns out and good luck!
OTN: Not a thing. I'm supposed to be studying.....
future plans: Afghan, baby blanket and a cabled...something ;hats and mittens to follow for kids.
I think you might be able to achieve some softness with different yarn, maybe something thinner, and a blend of silk or alpaca. I've felted with KP Elegance and andean silk, and they are both super soft and flexable... but you'd be knitting that blanket for years!
Otherwise, I concur: it might be too stiff... you'd had a log cabin rug instead.