The humble washer often gets overlooked during building projects, but the truth is that these small discs actually serve a number of important purposes. Washers provide balance and support for bolts, but they also protect surfaces from damage due to contact wear. Without washers, bolt heads may become chemically fused to surfaces over time, and excessive wear and over- or under-tightening of can lead to stability concerns without a washer to balance the load.
More importantly, your choice of washer can be a safety issue. This is certainly the case when working around electrical components. In these types of environments, plastic washers are often the go-to choice for gaining stability, strength and durability while also receiving protection from current.
Speaking of plastic washers, another benefit to relying on plastics is that they are malleable during manufacturing to allow for customization. For example, you can get plastic washers stamped to your specs because plastic is easier to work with during molding. With many metals, the forging process means that making adjustments to the finished product becomes difficult or impossible.
When choosing washers, whether they be plastic flat washers, aluminum washers or anything in between, size matters. Not only is it necessary for the diameter to match your bolts and bolt heads, but you also want to ensure that the thickness of the washer is appropriate.
A washer that is too thick can lead to stability and strength concerns since there may be too much space left between the bolt head pressure point and the surface to which it is being affixed. If the diameter of the washer is too large or doesn’t align properly, it may spread the pressure and tension to a point where the connection becomes less stable.
For these reasons, you’re encouraged to follow the recommendations of the bolt manufacturer when selecting washers. These recommendations may include dimension information as well as pressure rating and chemical interaction information.
Material Choice Matters
As stated above, choosing the right material for your washers is vitally important. To ensure safety and to get the longest life out of your project, you want to use washers that are rated for your usage.
Once again, this is where following manufacturer instructions becomes a matter of importance. If your bolt manufacturer recommends using black plastic washers to insulate a metallic surface and connection, the use of metal washers may not be a good idea. As an added benefit, following recommendations can save money in some cases since it isn’t always necessary to go with a more expensive washer material choice when an alternative is recommended.
Likewise, some manufacturers will recommend certain metals over others due to the potential for bonding. In many cases, stainless steel washers can be used on a variety of surfaces due to the chromium contained within the metal. This prevents corrosion which plays a big part in metals fusing together over time.
Tool Choice Matters
Interestingly, one of the biggest factors in choosing the right washer doesn’t even have to do with the washer itself; it’s the choice of tool that makes a difference. Using the wrong tool can lead to over- or under-tightening. The wrong tool choice can also cause you to strip bolt heads and screw heads which can lead to big trouble if changes need to be made to a project later or if a tightening error occurs.
To choose the right tool, consider manufacturer recommendations, but also rely on common sense. Washers should never be forced as the pressure can warp the washer’s surface and leave it ineffective. When working with a washer, the connection should feel firm. If you’re experiencing a washer that is spinning or providing give, you may need to rethink your tool choice.