Check your tools! Some items such as crescents wrenches May be confiscated if in your carryon!
How do people carrying tools like wrenches manage to keep their checked bags under the 50 lb. limit? The tricky part with carrying tools and spares is to balance benefit and likelihood of needing it with the extra weight. Before a recent trip I had the idea to carry a spare first stage and a spare long hose, but it turned out there was no way I was going to make the weight limit.