A good screw can be the difference between a solid product and something that falls apart when you need it least. Finding the right screw for the job is an art form in of itself, which is nothing to say of using it correctly and making sure it can hold up to years of wear and tear. When you’re not sure whether or not to use undersized screws or a micro fastener, the list below can help you with the basics. Screws are an essential part of building, repairing and crafting, making this one foundation you don’t want to miss out on.
Everything you use in an assembly needs to fit neatly together. Failure to meet this simple rule can lead to a lot of frustration and lost money down the road. A custom screw should have a custom shoulder bolt. A micro fastener can help in some areas, but other areas might require the ability of custom fastener options. Even seasoned professionals can slip up on these little details. How do you know you’ve got the right stuff?
Let’s talk about thread lockers first. There are two kinds currently available on the market. You have your inert thread lockers and your reactive thread lockers. The former is also known as ‘prevailing torque’, that of which creates a secure fastening lock that is noticeably resistant to vibration and any form of slippage caused by shock. For objects that will face a lot of stress and movement, these are invaluable additions.
We’ve touched on torque, so let’s keep going to keep you updated on the basic know-how. A breakaway torque is necessary to start what’s known as a relative rotation. This is between a locking fastener and its mating thread with no axial load on the screw. This changes with reuse and is known, subsequently, as the ‘1st Off’ torque, the ‘5th Off’ torque, and so on and so forth. Keep track of these somewhere you can easily find to avoid headache.
What do you need to know about said axial load? Remember the measure of the axial load is imparted on a fastener. The amount that’s applied to the seating torque is most often measured in pounds per square inch to create the tension needed to make sure nothing is coming lose right under your nose. While a commonly accepted percentage is around 80% to 85%, double-check your manufacturer’s recommendations to save yourself the trouble.
Now to get into the heart of undersized screws, miniature screws and small screws. Hi-lo screws are known for having a much more reduced minor diameter as well as less plastic material. These minimize stress and are considered a superior option than what was available just years back. Combine this with a double lead high as well as a low thread with a 30 degree thread form and you have the most positive thread engagement available.
For those eager to find some brands to start off with, Delta PT screws have an impressive 50% improved torsional as well as tensile strength for the same diameter. You also have SEMS screws, that of which combine two separate parts into a low cost fastener for easy usage. These are considered highly adaptable and can be used for a wide variety of applications, making them indispensable for do-it-yourself homeowners and professionals alike.
Undersized screws and tiny screws may be small and tricky, but becoming comfortable with them is the key to creating products that last.