Lets all welcome @Carl_Snarl to the forum!
I’m sure everyone already knows, but he is the owner of Metal Guru and is a supplier of tubes and parts. I think he does a great job of posting the specifications of every tube. It’s better than Columbus’s own website 
. In addition, Carl teaches framebuilding classes. Being a supplier and educator makes him a great resource for the community.
Carl will happily respond to your emails, but if you this forum to ask questions, make product requests, stock questions, etc, you will help the reduce his communication load.