Fastener Design Course Part -6 : Dowel Pins | Role Pins | Fasteners holes | Countersunk Hole
Channel: Fasteners
Date: 2021-03-29

Match drilling of fasteners holes:
Although proper match drilling can protect and enhance the appearance of a fastener hole, it still has limitations and is not always the best choice for all applications. This video discusses match drilling as a method of locating and creating the pilot hole in the work piece, as well as some of the issues that may arise during the process.

The first step is to drill a hole in the center of the fastener. This hole should be slightly larger than the diameter of the fastener. With the first hole drilled, the next step is to measure the exact distance between the top and bottom of the hole. (The distance between the bottom of the hole and the top of the fastener should be slightly larger than the thickness of the material you are drilling through.)

Dimpled and counter sunk holes:
Most fasteners, such as screws and nuts, have a head that is designed to fit a specific type of fastener recess. The recess is a dimple, counterbore, or counter-sunk hole that allows the nut to hold the screw or bolt firmly in place. The recess is threaded to match the fastener and is designed to prevent loosening in use. There are several different types of fasteners, and each type of fastener is used in specific applications. When selecting the correct fastener for a given application, there are many factors to consider, including the size, shape, and type of material to be fastened; the size and type of the hole in which the fastener will be installed; and the desired design of the finished product.

Dowel Pins:
The concept of dowel pins as a means of connecting components together is not new. The ancient Greeks used dowel pins to hold together the parts of their chariots, and Leonardo da Vinci used a version of the dowel pin to connect the shaft and wheel of his design for a helicopter. In the modern era, dowel pins continue to play an important role in many products, from the stock and barrel of a gun to the handles of a pair of pliers. Dowel pins are actually important in many areas of construction. In a typical wooden door, for example, there is a hole drilled right through the door. From the outside of the door, you can see the hole where the dowel, or pin, penetrates. The hole is there to align the door. A dowel pin is placed through this hole and a hole that is drilled in the door frame. They are used as support to stop the two pieces from spreading apart.


Fastener design is the process of using engineering principles to design fasteners for use in a product, system, or structure. One of the best ways to learn fasteners, in particular, is to sit down with an experienced practitioner and listen to him or her explain the ups and downs of their career. Richard T. Barrett is an aerospace engineer (aerospace engineer) at NASA Lewis Research Center in Cleveland. He has been involved in aerospace and rocketry for over forty years, including work on the Space Program, rocket engines, and launch pads. He is one of the world's experts on the subject of fasteners and fastener design.

Role Pins Design Criteria

Source: http://www.sti.nasa.gov​
https://www.youtube.com/channel/UCI9BX-UcPOhsfr0fTklLytQ

Richard T. Barrett, Senior Aerospace Engineer of NASA Lewis Research Center presents a comprehensive course on fastener design. A recognized expert in the field of fastener technology Mr. Barrett combines lecture, charts, illustrations with real-world experiences. Topics covered include: materials, plantings and coatings, locking methods threads, joint stiffness, rivets, inserts, nut plates, thread lubricants, design criteria, etc.