Personally, I prefer aluminum tubing brake lines, or steel. Steel brake lines are very light weight and can usually be found at some auto supply stores and for sure at companies that make custom hydraulic hose lines. Lots of steel hydraulic lines are used on tractors and many different kinds of dirt working machinery. I guess anything can break eventually but after being involved in building Variezes, LongEzes and Defiant, monitoring the ezes for almost 30 years, there has been many torn up eze types from a melted, cracked, come loose from fittings, and or broken aged plastic lines. After all of the problems I have heard about the plastic lines including aging and needing to be replaced at some point there is no way I would ever use any plastic lines for something as important as my brakes. I like doing something one time without thinking that I will have to replace sometime in the future. With plastic you will eventully have to replace if you keep your airplane long enough.The Ezes rely upon braking for steering and is critical to staying on the runway. Lose one of your lines due to one of the reasons listed above and you are in a mess which many in the past have been. I am not saying that using plastic lines is a major problem but it has been a problem. The Vans aircraft use aluminum brake lines or they used to when I helped my neighbor build his RV6A many years ago. I don't think I have ever heard of a RV breaking a brake line and they rely upon differential braking for steering as well. Plastic lines are easy to install but so are metal lines. Larry H.
Wait a minute. I don't think that makes any sense! What you meant was that plastic was the problem, I suspect, not that it was too big. Mine are 3/16", and work fine except for full throttle, which is certainly good enough to stand it on it's nose at any given time. I'm not sure where I got the 3/16" sizing from, but it was somewhere from way back in past history. One thing I'll do differently on the next plane is install a plastic conduit that will allow easy brake line replacement, rather than clamping and floxing the tubing directly to the spar!
