Piston-style musical instruments rely on smooth, true cylinders for proper tone quality and instant note response. If a valve body becomes damaged or worn, the horn is, of course, "of no use" to the owner. Many horns with these types of problems can be saved by trueing, honing, plating and final lapping to restore the smooth bore.
Complete Piston Refit
This job is for those who desire us to take care of ALL the details concerning the restoration of the valve action of their horn. The proper way to refit pistons is to hone and true the pistons and the valve casings until you have a true cylindrical shape with no leaks between ports. Then a comparison must be done of the casing ID and piston OD. The difference must be made up by copper building the piston to the casings current size. Next the piston must be honed back down undersize and nickel plated and honed to the final size. Finally, the piston is hand lapped into the casing producing a smooth fit. To check our refit, the horns slides must be included. Once completed, this instrument is ready to play.
Piston - Hone To Size
Honing only the pistons to size is a job option typically requested by repair shops only. Final fit is performed by a technician. For this job type, we only require the pistons(s) to be worked on and the specific size required for each. We will strip, prepare, and nickel plate the pistons slightly beyond the requested size. Then hone them back down to the exact size. Note that no casing work is performed under this option. It is the customers responsibilty to provide accurate measurements in writing of desired size, at minimum down to the thousandith (.001").