Bump tube holes

[domocles]

I am new to inventor but this thing should be fairly easy. I want to make a tube with a series of bump holes. I can make the tube no problem by creating two circles and extending them to the desired length, but when I go to add a hole it just doesn't want to know. I tried using a sheet metal flat design but I can't seem to wrap it into a tube, any ideas?

 

[jvo1]

I usually end up either making a work plane, or sketching off one of the origin planes. Since its a tube, it shouldnt really matter which one you pikc. Then you should be able to get the desired hole.

 

[DesignerMike]

I usually constrain the tubing sketch to the center point so that the origin planes are passing through the center and then use one of the origin planes as the sketch plane for locating.