Marji - I went shopping for underlinings

Yesterday the sun was shining in St Louis, it was a hot humid day, and most people were outside, doing whatever it is that people do outside on weekends. Perfect day for me to make a trip to the last independent all-purpose fabric store left in our area.
So I pulled out my 4 pieces of wool and trekked off to the store. Fortunately people were outside and the store wasn't busy, because I spent 2 hours and used up a whole (short) counter while I draped fabric over potential underlinings.

First up was my yummy piece of red cashmere (The Wool House, Toronto, 2005). It's a light-coat weight or heavy jacket weight. I unfolded the fabric, pulled some bolts of potential underlinings, and proceeded to unroll a bit of each of them in turn. First I would line up my selvage edges - potential underlining and cashmere, so that the grainlines matched, and then drape the fabrics over my arm, trying to come up with something I was happy with. I ended up with a piece of silk batiste that is light as air - matches the light-as-air feel of the cashmere, and the drape of the two are beautiful together. The silk batiste doesn't add any bulk or weight to the cashmere, yet it's tightly woven and will prevent any bag out at the elbow or undue stress on the cashmere. It was pricey - but so was the fabric.

Moving on to the Purple Ungaro felted wool. This piece of fabric is a mystery to me.
I've got to get a crosswise picture to insert here. It's dense, but the loft on the fabric is thinner than a dime. It's got a soft-finish feel to it, but is as tight as a worsted.
I expected, because of the thin-ness of the fabric, to end up with a china silk or a batiste. I was really leary of putting a cotton underneath it, because I don't want any wrinkle show-through and this fabric is fine enough to show what's underneath. (ohh, shades of challenges to come with this one - everything I put into it is going to have to be thought out and well done so that it doesn't look a mess). Well, this stuff is heavier than I thought. China silk, silk batiste, cotton batiste, all collapsed and didn't do a thing for it. The salesclerk pulled out some Ambiance - I really don't want to deal with Ambiance as an underlining - and fortunately it didn't work either.
Cotton broadcloth was too -something. It just didn't feel right, and I've got that issue of cotton broadcloth and the wrinkle factor.
I ended up with something I totally didn't expect - a fairly stiff cotton voile. It's perfect!
And that is the advantage of being able to stand in a store and actually drape the yardage. I never in a million years would have guessed that I'd end up with a voile for this one.

Next up was the coating weight double faced wool/cashmere blend that is a new piece, ordered for this project from Gorgeous Fabrics. It's the heaviest of all the wools I've got. I didn't think I was going to want to underline it at all - then I tried the knuckle test. In a corner that I won't end up using, I put the fabric over my knuckle and pressed hard. I ended up with a deformed bubble in the fabric - which is still there. I really don't want my elbows to look like that after one season, so, to find an underlining which won't change the drape of the fabric, won't add bulk or warmth, yet will provide support.
Again, the salesclerk wanted me to try Ambiance. - why, I don't know. Come to find out, she doesn't sew with wool, has never underlined anything, and is a quilter. I could tell she must be a quilter because she was wanting to feel the fabric with the underlining in a little 2" square in her hand, whereas I wanted to drape a half a yard of it over my arm. This store has shifted focus in the last 5 years heavily towards quilting. Anyway, back to the burgundy piece of wool/cashmere. Again, cotton broadcloth was too heavy for what I want, this is to be a jacket. If it were a coat I would have tried cotton flannel, but I have a problem with being too hot - I need less, not more insulation. I tried the usual suspects and again, none were right. Then I decided to try Imperial Batiste. It's a high quality cotton poly blend and can be found in stores that sell fabrics for heirloom sewing (you know, smocking and lacey/embroidered baby/childrens clothing). I went over to that section of the store and pulled a Spechler-Vogel 100% cotton batiste and the Imperial Batiste.
The Imperial Batiste won, hands down. It provided the exact amount of support I wanted without changing the drape of the fabric.
I bought it in black for both the wool/cashmere blend and an old piece of wool plaid I had with me.