i make tons of flannel quilts and quilts that include flannel- i mix regular cottons & flannels all the time- i love working with flannels. you can make any quilt you want with flannel- it's just a softer cotton than the regular cottons. one year our lqs was offering a (saturday sampler) program with different star blocks each month- they offered it in 30's fabric, batiks & flannels- i chose to do all 3...it was GREAT- all 3 different (styles) of fabric made very different looking blocks - the flannel one was definitly my favorite finished quilt- and i had 3 family memebers almost fighting over who should get it.
i know people tend to (freak out) over pre-washing flannels----some people wash them over & over again multiple times- (then complain they pill)
i do not always pre-wash my flannels- if the are kind of thin- a loose weave i will pre-wash them (once) and dry them in a hot dryer- to tighten up the weave & give them more body- but if they are nice (meaty) flannels i don't always-unless they are a dark-saturated color i'm worried about running- and when i do pre-wash i only wash them once- gently-on a short cycle- then dry in hot dryer- i''ve been using flannels for 40+ years and haven't had any *after the fact* problems with having not pre-washed.
here's a picture of the (all flannels-some pre-washed some not) crazy patch work quilt i made for my sister a couple years ago- it also has a flannel backing & hobby 80/20 batting
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