Why wouldn't you show a tech what you think is the problem? When we get your horn, we look it over in front of you and give you an estimate. We then go in to the back and take a more detailed look at it because we know what symptoms are caused by certain issues. There are many many things that can affect the valves. Much more than the average player knows about because most players aren't taught about the mechanics of the horn. You should never have the feeling that you should "make the tech do his job" when you bring in a horn to him. A good tech is one you trust, that tells you what is wrong and what is required to fix it. You think a valve alignment will fix valve troubles? Not really. It could be one or more of any of these things Casing isn't true Piston isn't true Piston is burred/dented Casing is burred/dented Slide tubes are out of alignment Build up on piston or casing No oil (90% of valve issues I deal with are because the kid didn't oil it) Improperly installed valve guide/spring Burred valve guide Burred spring box. Bent valve stem Overtight valve caps Horn soldered together with a lot of stress Dirty casing/piston player pushing valves at an angle plating coming off piston etc etc etc Each of them has many ways to fix them, but the right way is the way that the tech will know of and the player will likely not know of. Leave it to the tech to do a proper diagnosis. I have never done a valve alignment that fixed a valve that hangs. I rarely replace a valve spring and have the valve work again. I am done my rant. I just didn't agree with your "make him do his job" statement, and then your recommendation of a fix that will likely not solve his issue.