Posted by Lee Stofer on February 23, 2004 at 07:38:53:
In Reply to: Scope to see inside an instrument? posted by Leland Jordon on February 22, 2004 at 23:50:34:
If the purpose is simply alignment of the piston or rotor, then a scope is unnecessary. Rotor valves are almost always well-marked with alignment marks, and piston valves can be easily aligned using a piston valve alignment tool which is available from instrument repair supply companies for no more than about $10.00. These have some sort of hook at the bottom, which is inserted into the lowest port in the valve casing, then while holding pressure to keep that at the top of the port, the top portion is slid down to the top of the valve casing and turn a screw to lock it in place. When it is set, the tool is remove from the casing, the hook is inserted in the corresponding port on the piston while holding the tool next to the piston, and the upper portion will show exactly how much cork washer and felt is necessary to align the piston. After the right thickness of material is installed on the piston stem, the same measurement can be used, and the hook is inserted in the port for the down-stroke, and that will yield the correct measurement for the finger button felt. Any competent instrument repair technician can easily accomplish this for you, and not charge an arm and a leg, either.
Lee Stofer