All types of threaded insert require installation and all the varying methods of installation require different tools. Threaded-in inserts are the most simple and can be installed by anyone; the other types require specialised equipment and are not recommended for a DIYer.
Threaded-in inserts
Inserts which are threaded in have external threads, as well as internal threads and are threaded in like screws. They are either self-tapping or require tapping in order to be threaded into the hole using specialised tools.These inserts are usually for use in metals, but can also be used with wood.
Moulded-in inserts
Inserts can also be inserted during the manufacturing process. For some plastics, this involves moulding the plastic around the insert when in liquid form. The insert is therefore set in to the plastic when solid. These are mould-in inserts; they create permanent threads in both thermoplastics and thermoset plastics.
Ultrasonic and thermal insertion
Ultrasonic and thermal insertion is another way of installing inserts into plastics. Instead of being moulded in when the plastic is in liquid form, they are installed by applying heat to the area where the insert is to be placed, slightly melting the surface of the plastic and allowing the insert to slide into a pre-made hole; it is then secured by the resetting plastic.
Pressed-in inserts
This type of insert is pushed into a pre-made hole, usually using an arbour press or hammer. These inserts are designed with knurls which take to the material; this increases the pull-out resistance.Press-in inserts can be used in some woods and plastics.
