Originally Posted by
KC8QVO
If you can see the wall thickness you can measure it. As to how precisely - if you were trying to make an emergency repair I don't think a precise measurement is required. If you can see the wall thickness you can see that it is pretty thin. If it is pretty thin that will be a good guide to whoever is doing the repair as to how much heat the parts can take.
You can’t really “see” how thick or thin the wall of a bicycle tube is by just looking at the vent holes. Someone doing the repair who isn’t familiar with bicycles…by far the most likely scenario…may not even know about the vent holes in the frame. I’m also going off my experience long ago with a welder who was used to delicate welding and a cyclist himself. He was the one who was surprised by how thing bicycle tubing is.