ArticleCalibrate your Winemaking ToolsWritten by Chris ColbyYour hydrometer shows that your must has a specific gravity of 1.100 - but how do you know that's accurate? Learn how to calibrate your hydrometer and all your winemaking tools, so you can be sure.Already a member? Log InYou'll Also Like Article MEMBERS ONLY One Wall Winery: One World. One Winery. One Wall. If you have a free wall in your garage, you can have your entire winery organized there. See the plans by Steve Hughes. Article MEMBERS ONLY The Retirement Plan All good things must come to an end . . . and that includes your winemaking equipment. Let’s run through the signs of when it’s time to replace equipment, when it can be restored, and how to best preserve it for a few more seasons.