Trojan Special Fastener is a specialised manufacturer of internally and externally threaded fasteners. We make these in our factory in Birmingham.

Slotted Nuts

Thursday, September 21st, 2017

Slotted nuts are often called castellated nuts. They have slots cut into one side. Typically there are a total of 6 opposing slots, but this number can vary - in very large nuts 8 are common, as well as 2 in smaller nuts.The name comes from the nut's resemblance to the parapet of a typical medieval castle. The slots are designed to align with holes in a mated bolt to accept a cotter pin, a split pin, R-clip or even safety wire to be inserted, which then locks the nut in place and prevents it from loosening and turning. Don't confuse castle nuts with slotted nuts. Castle nuts have a round reduced section formed on the section where the…

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5/16 UNF hex set screws 3.1/2 inches long

Thursday, September 21st, 2017

Whilst making bolts, setscrews and other externally threaded rods is not our speciality, we still managed to precision machine these 3.5 inch long (under the head) hexagon set screws in bright mild steel. Our customer said they needed them quickly and to their drawing with a very short plain section, so in record time, we turned these out. A set screw is a type of screw used to secure an object within or against another object, normally not using a nut. The most common examples are securing a gear or pulley to a shaft.

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1.1/4 UNC to M20 Connecting Adapter

Wednesday, September 13th, 2017

In a cost saving exercise for our customer, we manufactured 4 pieces of the unified to metric threaded hexagon connector nuts. Our customer wished to use a brush head on a device that came in unified form and he could only get the attaching rodwork in metric. We said no problem matey! We figured out the amount of thread engagement he needed and machined a prototype which he tried out - it worked as expected and so we machined a few more! Mixing threads on one kind of nut is not an issue for us. Typically we manufacture a large quantity of right handed to left handed adapters for some of our customers. Be they unified, whitworth or metric thread, let…

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Tuesday, September 12th, 2017

We recently manufactured a small batch of just 10 flange nuts out of naval brass for one of our customers. Smaller quantities are not an issue and as you can see, the quality is exceptional.

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M6 Special Flat Cap/Blind nuts

Monday, July 17th, 2017

It took us just 2 hours to make a small batch of these cap nuts to our customers sample. He didn't know what thread was being used and he found the cap the sample he had wouldn't go all the way. But we were able to modify the internal thread profile slightly to allow a deeper thread engagement without altering the overall size of the nuts. Another customer happy with our goods that they'll be ordering a much larger quantity from us!

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M12x1.75 Male to 1/2 BSW (12tpi) Female adapter with cross thread and grub screw

Thursday, December 22nd, 2016

A customer asked us to prototype an adaptor of theirs to join two incompatible parts, one with a metric M12x1.75 female thread and the other part with a male 1/2x12tpi BSW thread. We said no sweat. 1 hour later and we have the prototype ready to use along with our suggested cross tapped hole with grub screw for fixing. Not bad I'd say!

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1/4 BSF Single Slot special nuts to drawing

Tuesday, December 13th, 2016

We were provided with a customer's drawing and a sample to work from on this part. It involved a number of different processes, and ensuring the finish was right was key to this product. Trojan drilled, chamfered, turned down, threaded and slotted the nuts so quickly that our customer was surprised the day they landed on his doorstep.

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Monday, December 12th, 2016

We made some nylon insert nuts in a fine pitch format out of CZ121 (CW614N) hexagon brass bar. These were made to DIN985 standard and are often known as nylock nuts or nyloc nuts. These are a prevailing torque type of nut that uses a nylon ring to create increased torque upon application. When the nut is tightened onto a bolt or setscrew the nylon ring deforms and creates a tight frictional fit which reduces the risk of the nut loosening upon vibration. We typically use Nylon 66 in a natural colour for this. We typically use Tecamid 66 material for this.

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M4 to M3 reducing hexagon coupler nut

Thursday, December 8th, 2016

We just made some M4 to M3 reducing hexagon coupling nuts for one of our regular customers in 303 stainless steel material. The nuts are tapped half way in each thread form from either side. They took a few hours to make and none were rejected during our testing process. This is an example of a special nut made to a customer's verbal specification. We did this without a drawing or a sample. We're trying to make smaller special nuts than our usual size limit. We can make double ended hexagon coupling nuts with any mixture of thread forms on one thread. If you want to mix metric and unified - no problem. If it's machinable, we'll do…

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