Testing a sample versus washing the whole piece of fabric
 

FOR ME - and this is MY opinion and MY experience -

it seems to be about as much work/bother to test a small sample of a piece of fabric as it is to wash the whole piece.

I agree. I just wash it all. Plus I prewash not just for the risk of bleeding dye but also to pre shrink the fabrics and batting.

When I test a fabric, I snip off about a 2" square and drop it into a glass of water, leave it overnight, then look the next day to see if there are any streaks of dye in the water. If not, I fish the scrap out and rub it against a couple of light fabrics I plan to use to see if any dye streaks that way. I do this only for fabrics I consider suspicious, which is usually only 1 or 2 for any given quilt.

If I were to wash all the fabrics, I would need to do at minimum 2 loads -- one for lights and one for darks. (If there is a "bleeder" in the lot, I would need to test further to figure out which one it is. Usually this would have been a suspicious fabrics to begin with.) I would then need to starch and iron all of the washed yardage to restore crispness and stability before cutting.

I used to prewash all fabrics; now I don't prewash any unless a suspicious fabric doesn't pass my tests (very rare).

For me, not prewashing saves me a ton of time. I do take care with the first washing of a quilt to use Synthrapol in a large washing machine that uses a lot of water, but I would do this even if I prewashed all the fabrics since, even with prewashing, there can be a "bleeder" fabric that just keeps on giving.

Batting controls shrinkage once there is moderate quilting in a quilt. (Batting is not in control with tied quilts or quilts with large areas unquilted.) That is, the fabric is constrained from shrinking more than the batting. I like crinkly quilts, so I am fine with using cotton batting; it shrinks just the amount I like. If I preferred a smooth quilt similar to modern commercial comforters, I would use polyester batting.

I often wonder whether quilters who prewash all of their fabrics are simply a lot younger than I am, with more energy. Years ago, when I used to prewash, I had a lot more energy. These days I prefer conserving my energy for cutting, piecing and quilting!

I agree. Just wash it!

Eventually, most of us settle on a routine that we feel works for us.

I am reasonably sure the newbies must get very confused about whether or not to wash their fabrics before cutting them.

So we present our viewpoints - - - -

Me too. I don't pre-wash just because of bleeding. I like to know that the fabric is clean and free of chemicals and that I won't be surprised by shrinkage later.

I can understand prewashing fabrics to remove chemicals. What I don't understand is how testing fabrics could be as much work as prewashing fabrics.

I agree with Tartan. I like to sew with that factory sizing still on the fabric. I thought I would be odd man out. Harriet Hargrave taught me to put warm water in a small container, put tiny bit of quilt soap and the test fabric in. Shake it every so often like a washing machine. Then rinse and put it on a white paper towel. Works for me because then I don't have to press those yards of fabric.

I also just wash my fabric as it comes in the house. It is just one more load of laundry. If I have a fabric I think will run I will test it to see how much bleeding there will be. Then I know if I should do that separately with a fixative. If some fabrics bleed a little, a normal wash usually takes care of it.

By the way, I have never had a fabric ruin a quilt project because of bleeding. Is there a lesson here???????
peace