Having been badly burnt with colors bleeding on something I worked on recently (red, of course), I plan to always prewash from now on. I prewashed something yellow recently, and used a color catcher, and it "caught" a ton of dye. There's nothing worse than spending hours working on something, only to have it bleed all over itself the first time you wash it, trust me.

Where do you buy "color catcher"?

I just want to emphasize what crashnquilt says about prewashing. I learned this in a class I took on fibers and was surprised to say the least.

Formaldehyde, which, if you're unfamiliar with it, is the stuff they use to preserve dead things. When you see a dead thing floating in a jar with liquid in it, that liquid is formaldehyde. It's one of the most popular chemicals used in fabric because it kills bugs, and their eggs. Fabric is stored in warehouses before being shipped and bugs love warehouses AND fabric.

Sizing is also used in fabric. It's great because it makes the fabric smooth and even looking. When you wash out the sizing, your fabric may suddenly be not so smooth and very uneven.

And just because a fabric is 100% cotton, doesn't mean it has the same weave. Some are tighter than others, some threads are denser, you can tell by feeling the fabric.

And how many people do you think have touchy feeled that fabric before you? Now we're talking dirt and oil.

And dyes do run so washing with a color catcher to catch the running dyes, or using white vinegar, which will keep the running dyes from adhering to the other fabrics and will also "set" the colors in your fabric, is a good idea as well.

If you prewash the fabric you are assured that all the chemicals and whatever else is on it have been removed. After dyes have been released you will have the true color of your fabric. And with the sizing wash out, you will also have the true size of your fabric and you can straighten out any lopsided grain issues you may have as well.

I bought Carbona Dye Grabber at Joanns. I was making a quilt for a client, and even though I prewash EVERYTHING, when I was giving it a final press using steam..yup, the red ran onto the cream. I took it to the laundramat, placed the completed quilt in with the dye grabber (in their biggest washer)and crossed my fingers. It came out!! Not a hint of red. So now I use the dye grabber at home when I prewash darks.
bev. :]

Thank you. I'll be sure to buy that next time I'm there.

I always prewash, if only to get all the dust in the fabric out. Recently, I didn't prewash for one quilt. I noticed that my rotary cutter got dull more quickly than usual. I surmise it was the stiffness of the unwashed fabric that caused the blade to dull.

Just one more thing to consider.

I've mixed on alot of quilts. When I started in the late 70s everyone seemed to wash fabric, so I did. Stopped sometime in the 90s. I always clipped a small triangle on an edge when I washed, so I'd know.
I've not had any problems from mixing them.

grocery store