Threaded inserts are one of those items that you are using every day, without knowing it. They are part of so many every day items, like chairs, tables, toilet seats, plug sockets, cars, planes and many more. Threaded inserts are usually brass, steel or stainless steel and are used in plastic castings, housing and parts to create a metal thread to allow screws to be used in the products listed above.
Threaded inserts are often used to repair a stripped threaded hole, to provided a durable threaded hole in a soft material, to place a thread on a material too thin to accept it, to mould or cast threads into a work piece therefore to eliminate a machining operation, or to simplify changeover from unified to metric threads or vice-versa.
Threaded inserts are available in a variety of shapes, which are determined by their use and function. The cylindrical metal shapes, which are placed in holes to provide threaded tracks for bolts and screws, provide extra durability, strength and stability.
What size hold should be used for threaded inserts?
As each threaded insert is different, and each screw or bolt that is being inserted into it also differs depending on size and material, each hole will change in size too. Fitsco threaded inserts all come with a recommended hole size, which is what we advise to ensure that our threaded inserts perform to the highest standard.
Choosing the Best Threaded Insert
Choosing the best threaded insert is an essential part of your project, and finding out which one is best is determined by a number of factors, and we run through those here.
What type of material is the threaded insert going into?
The material (thermoplastic, thermoset or DMC etc) in which the insert will be installed will directly influence the correct choice of threaded insert, the achievable performance and installation method.
What ‘torque’, ‘pull-out’ and ‘jack-out’ performance is required?
Torque is the maximum rotating force (Nm) that can be applied to the insert before it ‘spins’ in the moulding. Pull-out is the maximum force (Kg), applied in a direct line, that results in the insert being pulled out of the moulding. Jack-out is the maximum rotating force (Nm) that can be applied to the threaded inserts before it starts to be pulled-out of the moulding and occurs when the design of the two mating parts has not been done correctly.
Do the threaded inserts need to be ‘headed’ or ‘unheaded’?
The majority of threaded inserts that we design, make, manufacture and supply are unheaded as they are usually installed flush into a blind hole. The headed style are used in a through-hole application to prevent them pulling through. They can also be used in applications where there is an oversize clearance hole in the mating part preventing a jack-out situation and for use as an electrical contact.
How to choose the appropriate brand of threaded inserts?
Fitsco offer several different types of threaded inserts to suit all types of applications, materials and performance.
How do you fit threaded inserts?
We are often asked by customers how they should insert their threaded inserts. When screws or bolts are threaded directly into plastic, wood, metal or fibreglass components, failures often occur. Threaded inserts provide stability, strength and durability to the joint. There are several methods of installing threaded inserts, including thermal and ultrasonic, as well as being pressed, moulded and screwed in.
What’s the best way to install threaded inserts?
There are two methods of installing threaded inserts; post-moulded and moulded-in. The three main methods of installing post-moulded threaded inserts are using heat or by ultrasonics by cold or screw-in, with each method having its own advantages and disadvantages. The easiest method of installation is to press the threaded inserts in cold. You will get a better performance if the inserts are put in hot, using some type of installation machine. The screw-in range of inserts has to be installed with specialist equipment and is therefore the hardest to method of installation, but provides the best performance. Moulded-in installation is the method that provides the maximum performance, but has the disadvantage of requiring the threaded insert to be installed directly into the mould tool. This method is mainly used in thermoset or DMC mouldings where cycle times are slower, so the time taken to install the threaded inserts is not too much of a disadvantage. The majority of inserts blind, which stops plastic material going inside the insert and contaminating the thread.
How do you install threaded inserts in composite or fibreglass?
The standard method for thick or cored composite is to epoxy a knurled threaded insert into a small hole. Another method is to tap the hole in the composite and install a self-tapping threaded insert, covering both hole and threaded insert with epoxy. With both types, the insert should be mounted on a greased screw to protect the internal threads from the epoxy. An insert that is bonded will be durable and stronger than a sheet-metal screw inserted straight into the fibreglass, but it is not an effective replacement for a thru-bolt with a backing plate.
How do you install and use threaded inserts in metal?
If a threaded insert is being installed in metal, most will require tapping the hole, although there are some types of self-tapping threaded inserts that can be used in soft metals. The taps are usually a special size and thread intended just for the particular insert, which will typically come with the insert as a kit. Coil threaded inserts may also require an insertion tool to tighten the coil.
How do you install and use threaded inserts in wood?
Threaded inserts which are being installed into wood can be barbed, which are usually pressed or hammered into the hole. Screw threaded inserts will prove to be more durable, however. These are typically inserted by spinning, like a wood screw. Some will have a hex socket and are installed with the use of an Allen wrench. Slotted inserts could be installed with a screwdriver, but due to the slot being fragile, the most preferred method is to thread a nut, then the insert, onto a long bolt. The nut should be locked against the insert, then the threaded insert should be turned into the hole with a wrench or socket.
Why use threaded inserts in wood?
Threaded inserts will provide strengthening, durability and stability to your products.
How do you install threaded inserts in plastic?
Threaded inserts are typically pressed into plastic with the assistance of heat. A more unorthodox method would be to thread the insert onto a bolt. Use pliers to hold the bolt with the insert in place of the hole, whilst applying pressure downwards. The bolt should be heated with a soldering iron, and as the heat transfers to the insert, which after a minute or so, should begin to sink into the softening plastic. Downward pressure should be continued until the threaded insert is at the sought depth, at which point the heat should be removed and hold the bolt steady until the plastic has stiffened.
Blog by Dan Stanley - 13th June 2019
Shortly after I joined Fitsco, after a bit of thought, I decided to apply for the company to be nominated as a finalist of the Shropshire Chamber Business Awards 2019.
It was a straightforward decision to apply, as I felt that Fitsco needed to shout about the fact they are one of just two companies making their own threaded inserts in the UK and that they weren’t doing enough to increase their own brand awareness in the local area.
I searched through the awards, and found three awards to apply for, which I felt that Fitsco had the best chance of winning, which were: ‘Best Small Business (6-20)’, ‘Best Manufacturer’ and ‘Technology, Innovation and Enterprise’.
I broke each award down into their own individual criteria and arranged for the team to meet to discuss ideas. As someone who had been in the role for less than two months, it wouldn’t have been possible to apply without the valued input of Phil, Jayne, Carys and Paul. Getting the five of us together in the same place at the same time proved to be one of the biggest hurdles in the whole process! We worked through the criteria, with all of us chipping in our own thoughts and ideas on each, and I had plenty to work with and talk about.
Another hurdle to overcome was keeping within the strict 750-word limit. On one of applications, nearly 2500 words were written. Trimming these down to be clear, concise and still focused on the criteria that each award sets out proved to be a thought-provoking task.
The awards applications were all submitted on the day of the application deadline, which was Friday 26th April, with the finalists announced a week later, Friday 3rd May.
During this week, I wasn’t expecting to reach the awards finals and I just worked on as normal, looking at other avenues to promote the world of threaded inserts through. On the Friday, the announcement day, I waited in anticipation for the announcement to come through, frequently checking the Shropshire Chamber website and Twitter feeds all morning to see if there was an update.
At lunchtime, an email comes through! The finalists of the ‘Technology, Innovation and Enterprise Award’ is announced – we didn’t make it. At this point I was disappointed and a bit dejected. I tried to reaffirm myself that there’s two more awards and two more chances for us to reach the final, but there was an overwhelming feeling that perhaps I thought the applicants across Shropshire were too strong this time, as there are hundreds of small businesses and manufacturing companies all over the county. But, soon after, an email comes through. We’ve done it. We’re heading to the final as a finalist in the ‘Best Small Business (6-20)’ category. Joy. Elation. Relief! It’s worth it. I send a WhatsApp to the team to let them know and congratulate them on their hard work in reaching the final and they are all delighted, as am I.
No sooner than the office of myself and Carys that day calms down, another email comes through from the Chamber and we’ve made another final, ‘Best Manufacturer’ this time. We have just reached the final of two out of three awards, and we’re all absolutely delighted.
The application process is now completed and we then looked forward to finding out when the judges will arrive, to show them around the world of designing, making and manufacturing threaded inserts.
There are several things I can take away from applying for business awards, and here is my advice:
- Be confident in yourself and your business. I have to admit, there was times in the process where I wasn’t sure if it was worth us applying. With it being my first effort at writing an application for an award, I didn’t think I’d be experienced enough and thought there would be more experienced businesses applying for the awards. But, having reached the final of two categories, the process has instilled confidence in myself and the business.
- Think about your business from the outside. Having only recently joined Fitsco, a few weeks before the application process began, I was able look at the company from the outside. It’s important to think about what you’re good at and what differs you from the competition.
- Look at the award criteria and be concise. It’s easy to copy and paste some general information from your website or a PowerPoint but look at what is required for each criteria and write about that. The 750-word count doesn’t allow you to waffle or talk about irrelevant information.
- Get more people in the team to contribute. This is an important stage to combine knowledge, where everyone will have their own thoughts and ideas on each individual criterion. I don’t have the technical ideas that some team members have, where as other team members have good ideas on the processes that are taking place. Contribution is key.
Blog by Dan Stanley - 12th June 2019
One of our most popular threaded inserts are ScrewFits, we keep asking ourselves why they are so popular with our customers. I have thought about why they’re as popular as they are, and the evidence of a high-quality insert is there for us all to see.
Our ScrewFit threaded inserts, or ‘Trisert’ or ‘Double Ended’ as they have been known in the threaded inserts trade, are a range of inserts that are available in three different design styles; ‘Headed’, ‘Reduced Head’ and ‘Unheaded’. The threaded inserts are a high-quality, high-performing and versatile insert, that are commonly used in injection moldings and applications.
ScrewFit threaded inserts are installed post-moulding in either plastic or wood products. They are self-tapping threaded inserts with four flutes, which reduces stress on the moulding by having a balance cutting action. One of the big product advantages of ScrewFit threaded inserts are that they have a very high torque and pull-out performance, suiting a variety of mouldings.
Having thought about it, in two paragraphs, we can really see and feel the benefits that ScrewFit threaded inserts have on the products that they end up in. Having shipped these inserts all over the globe, we can fully appreciate why they have and are becoming one of the most sought-after products in the world of threaded inserts.
Blog by Dan Stanley - 11th June 2019
At Fitsco, we are frequently asked by customers “what are speaker spikes?”. They are different from threaded inserts, the products that we are accustomed to making, but the supply and amount we produce, suggests that they are a product with ever-increasing popularity.
Speaker spikes are popularly used in the hifi and music industry. As suggested with their name, they are designed in the shape of spikes. The product is designed to work as feet for the speaker or speaker stand. They provide stability, as they provide a ‘grip’ in the surface that they are in and this means that they ‘couple’ with the floor and vibrational energy disperses from the stand into the ground. The stand and speakers are isolated from external vibrations due to the shape of the speaker spikes.
The most common use for Fitsco speaker spikes is that they allow the user to couple and decouple speakers at the same time. When the speaker is playing, a forward and rearward motion is created. When the speaker is moved forwards, something needs to be pushed back to create an equal and opposite reaction to adhere to the laws of physics. Speaker spikes help keep your speakers coupled in a way that you want them, whilst decoupling them at the same time. Coupling will attempt to eradicate the internal vibrations of the speakers and decoupling assists in preventing the vibrations which come from the environment surrounding the speakers.
The hifi or speaker is often too heavy to move backwards from the force of playing, and it will vibrate, which comes from the speaker and it disrupts the vibrations that are caused by the music being played.
Fitsco speaker spikes are manufactured with two different types; knurled and threaded. The speaker spikes will be made from a different material from your speakers and speaker cabinets, so it is of importance that it helps isolate vibrations in both directions.
Another reason why speaker spikes are installed is to prevent diminished sound quality from vibrations from the floor. Speaker spikes also ensures that the speakers and stand remain stable, which is particularly beneficial when your speakers are positioned on an unstable surface, such as a carpet.
For installation, most speaker spikes are screwed into the bottom of the speaker stand, which, in turn, is coupled to the speaker. The speakers can also be isolated by the speaker spikes sitting on a pad, which is not an essential item, but it does ensure that the floor is not scratched or damaged.
Speaker spikes are an essential part of music fans receiving the best audio experience.
Blog by Dan Stanley - 11th June 2019