When I pin my quilt together with quilting safety pins. After I quilt and take out the pins they leave a little dark spot where they were pinned on the quilt how do I prevent this. thanks
Some people have body chemistry that causes them to be allergic to some of the metals or to cause discoloration on their skin from the different types of metal used in jewelry. This is what may be happening to make the dark spots on your quilt. In handling the pins, there is some sort of chemical reaction that causes the black spots to rub off the pin and unto the quilt.
Safety pins are constructed from wire made of either hardened brass or high carbon steel. Then they are coated with nickel or gilt. The steel wire is plated in order to strengthen it against rust and corrosion. Brass wire will not rust. The primary reason for plating brass safety pins is for their appearance only. Nickel plating gives a silver appearance and gilt plating gives it a gold appearance. You will not be able to determine whether a pin is made from brass or steel by its appearance. Brass pins may be plated in nickel for a silvery look and steel pins may be plated in gilt and have a gold appearance.
The best way to know you have quality safety pins is to purchase your pins at a reputable fabric or quilt store. Quilter's safety pins are now available with different color coatings especially for quilters. You may have to experiment with different brands to find one that does not cause the black residue to be left on the quilt. When you find a brand that you can use, keep them in a separate container. Use them only for basting quilts.
This problem does not happen just with safety pins. As a matter of fact, if you secure your quilt top with oxidized pins before stitching it, you will have dark spots all over your quilt.
In case your pins (any pins, not just safety pins) have oxidized, you can clean them with what some call "a pepper" while others call "a strawberry".
It's a small bag of emery (fine sand) that scrapes the rust of the pins. You can get it at any quilting store that carries pins.
Here are some pictures of such "pepper":
Stick a pin in it and move it back and forth a few times.
Once you clean your pins, they shouldn't leave dark spots on the fabric. Of course, you would have to do this periodically.