I have made several of baby quilts but would like to make a quilt big enough for a twin bed. Any suggestions for a batting that is heavy/warm enough for a bed? I like using cotton batting and I machine quilt. Thx

I always use Warm and Natural.

I like Mountain Mist Blue Ribbon cotton batting, but it is an old-fashioned batting that requires close quilting (2"). Warm n Natural has a bit of a stiff drape for me, and it can make a large quilt too heavy for my taste; however, many people like it.

Warm and natural is great and not really heavy.

warm and natural; dream poly; dream wool (my absolute favorite!)
hobbs 80/20; dream silk/bamboo blend (expensive but oh sooooo nice!)

Warm and natural.

I use warm and white for all size quilts.

I've always used warm & natural. However, I just read that it's NOT 100% cotton so I may switch. I hate that they call it cotton when it's not all cotton.
http://loftcreations.blogspot.com/2010/08/batting.html

Warm and Natural gets my vote.

depends what you like. If you like the thickness of typical quilts, like what you see int he store then buy 80/20.

If you like more the thickness of a comforter then you will need to use a thicker batting, but it will be more difficult to quilt.