Tag Archives: metric fasteners
If you want to boost the speed and efficiency of your assembly processes, you should look into SEMS, or “pre-asSEMbled” fasteners. These handy devices combine the screw and the washer into a single component, eliminating the need to match the right items up and slip the washer into place by hand. It also simplifies your inventory by giving you one part to track and purchase instead of two. SEMs have been around since the 1930s and come in inch-measure or metric varieties. (Guess which kind we sell!)
SEMs typically come with some form of lockwasher to prevent slippage once the screw is firmly secured. Two popular choices include internal-tooth and external-tooth lockwashers. Internal-tooth SEMs have teeth inside diameter of the lockwasher to bite into the substrate and hold the washer in place, while external-tooth SEMs perform the same task with teeth extending from the outside diameter of the washer.
You’ve probably heard a lot about stainless steel this and that. but what’s the big deal about stainless steel — and when do you need to choose stainless steel fasteners for your project?
First let’s examine what goes into stainless steel that makes it, well, stainless. Ordinary carbon steel met the world’s steel needs for centuries, finding its way into everything from building projects to swords, but it was by no means a perfect metal. Before you could say “Taste my steel!” the exposure of the steel’s surface to oxygen would lead to oxidation, which would show itself in the form of iron oxide — in short, it would rust. The more corrosive your environment, the faster oxidation would take place. If you lived by the seaside, forget about it.
Mr. Metric’s Custom Services for Metric Fasteners
You may have noticed that Mr. Metric offers plating among its other custom services for its clients. This means you can choose from a plethora of zinc, cadmium, gold, nickel, chrome and other finishes for your metric bolts, metric washers and metric nuts. But why does the choice of plating matter — and how do you know what kind of plating to select?
Plating is simply covering a conductive surface with a metallic coating, such as hot-dip galvanization to coat a steel fastener with a layer of zinc, or electroplating to add a layer of cadmium or chromium. We do this to take advantage of some desirable characteristic in the plating material. Sometimes that characteristic is purely cosmetic. If you want a bright, shiny look to your screw heads, get them plated in chrome. If you want black fasteners without having to paint them, order them in black zinc.