I was hoping someone could share some techniques for recalibrating manifold gauges. My R-22 and R-410A sets were in storage for a few years, not pressurized, while I was out of work. Recently I used them on job sites only to discover both sets are way off. While they were hung in storage, they were repeatedly knocked off their hooks by careless "helpers" (aka: friends of mine that are clueless to the sensitivity of gauges). Any help would be greatly appreciated. I am not permitted to join the Professional Member ranks as of yet and cannot access a link to another thread which provides the details I seek. Thanks!