Q. "Does soft copper have less copper content? In other words, is it less or more pure than straight lengths?"
A. Hard and soft copper (unless utility grade) are very pure in copper content (99.9% pure copper with no other metals mixed in). The only difference is the way they are made. There are differences in thickness in copper grades of pipe. We like refrigeration grade because when we get it, it is "sealed dehydrated" (cleaner than most other grades). Many codes insist on certain "types" (K, L, or M) of copper and so, if you are plumbing a house, etc. please do not assume that the copper tubing that we offer is code in your area. Check with your local code authorities before ordering. Generally it is "best" to purchase your copper fittings from us and to purchase your copper pipe and tubing locally. The main reason that we offer the copper tubing above is for people that only need a small amount or short lengths as well as we offer sizes not found in many local hardware stores and home centers.
Q."I have 'refrigeration grade' copper tubing. How do I determine which size copper sweat fittings to use?"
A. Refrigeration grade soft copper tubing is sized according to the outside diameter of the copper pipe. The plumbing industry uses the inside diameter (nominal) size of the pipe for their measurement of sweat/solder fittings. To determine what size sweat fittings to use on refrigeration grade tubing you must subtract 1/8" from the outside diameter of the copper pipe measurements. If you have 1/4" outside diameter refrigeration grade tubing then you will need to order 1/8" (nominal) sweat/solder fittings. Copper sweat fittings are not available for 1/8" or 3/16" O.D. copper tubing.