I Don't pin the bottom of my quilt tops and these clamps work great, even if I'm using the CompuQuilter. Need to call shop to order, not on website.

http://www.quiltshop.us
 

Using the Deelybob makes any size cone a snug fit with no rattling around.
I even use it on my Singer Featherweight to hold a cone of thread.
You will want a couple of them.

http://www.deelybob.com
 

One pair does the trick.
Nice even tension. I use these clamps and my regular clamps to stretch sweatshirts out to sew on the longarm.

http://www.quiltshop.us
 

I use these all the time to mark spines in borders and blocks for freehand feathers and I use them to guide the hopping foot too.

http://www.quiltersrule.com/template/nestedMain.html
 

$10.00

I usually turn off my machine light because I can see better with side lighting, especially when it's tone on tone.

I use one on each end to hold up my clamp straps.