Military Insignia

Badge Manufacture

Badge design and manufacture

This is a précis on the various stages of the manufacture of our products, and details some of the techniques carried out before the product finally sees the light of day.

The Master

With the decision made to produce a product, we then have to produce a number of designs, however, with most of the items that we have produced; and are going to produce, most of the designing has been done for us.

To produce for example an identical gold or silver badge of 16mm x 12mm, of a Regimental cap badge that is 43mm x 28mm requires a master to be made which is identical to the original badge but significantly larger.

The reason behind this is, because it is easier to make something larger to an accurate scale than something considerably smaller to the same criteria and level of accuracy.

The material used to make a master can be as simple as standard clay through to commercial modeling materials such Primo, Cernit, or Fimo. Each material has its own qualities, some are more suitable for jewellery, whilst another for dolls heads and porcelain work.

Considerations such as time constraints, how difficult the material is to work with, how long will the master take to dry out before further work can be done with it.

Master Mould

With the master completed, we now have to make a mould from it. This involves the production of a moulding box into which the master is placed having wiped the inside of the box and the parts to be moulded with a release agent. This allows the master to be easily removed from the moulding box after the mould has cured.

There are many moulding materials available on the market, Silicone, Polyester resins, urethanes Epoxies the list is endless, each designed to lend itself to the quality of finish required, the material that the master is made from, how complex the mould is going to be, and what facilities you have available to work with to carry out this type of work.

The Engraving Master

From the master mould we now have to cast a second master, this one will be from a far harder material such as acrylic which has the qualities of stiffness; it's stable as a material, no shrinkage, hard wearing, easy to work with, not expensive.

This master, when produced will be used to machine a master in brass, that will be the exact size of the item we wish to produce, in this particular case a Regimental cap badge 16mm * 12mm.

Engraving

The master is mounted in an engraving machine that was designed and manufactured in our own workshop a number of years ago.

With this machine we have the ability to produce a casting master of any size (within the capacity of the machine) which will be an exact copy of the larger master, it therefore it goes to say that the more accurate the master is to the required dimensions and scale, then the casting master will be as accurate as the original form.

The process of engraving the casting master is done in our workshop, and requires a high level of concentration by the operator in working the machine, whilst monitoring the cutting process through a high magnification lens.

The Casting Master

The casting master is nearly the end of the process and represents the exact shape, size and detail in brass of the original large master we made earlier.

Why make it from Brass and not aluminium or steel? Brass takes on a good finish it's ductile, easy to work, and is very stable as a material. Having passed inspection it’s now time to dispatch our master to the gold smelting company who carry this work out on our behalf.

Casting Most casting carried out by smelting companies is based on the lost wax method or centrifugal induction casting. Both systems are ideal for picking up the fine detail in the master, to such an extent that fingerprints have been found embodied in the work.

Lost Wax

The Lost wax process is shrouded in antiquity, it gives of an air of a Dickensian process involving black magic, heath Robinson devices and procedures designed to endanger life and limb, of all those in the vicinity of the glowing furnace.

This Process however has been used for thousands of years to produce objects in metal which could not be produced any other way due to the complexity of their shape.

It permits anything that can be modeled in wax to be faithfully transmuted into metal, and is still used to day for certain industrial parts, fine jewellery and sculptures.

Induction

A typical induction heating system consists of the induction heating power supply, an induction heating coil, and a water-cooling source, which cools the coil and several internal components inside the power supply.

The induction heating power supply sends alternating current through the induction coil, thus generating a magnetic field. When a work piece is placed within the coil and enters the magnetic field, eddy currents are induced within the work-piece, generating precise and localized heat without any physical contact between the induction coil and the work piece.

For complex parts this process is usually carried out by having the whole mechanism fitted to an arm which can rotate at high speed inside a guarded cage and is known as centrifugal induction casting.

Hallmarking

Having received the castings ordered; which had been made from our casting master as supplied to the smelting company, we now have to finish the product ready to send them to the Assay office for hallmarking.

Care has to be taken at this stage in order that during the removal of the sprue's and risers that we don't damage the insignia.

Any polishing required on the product has to be done very carefully in order not to eradicate any fine detail on the badge.

The badge, now fitted with its mounting pin is ready for dispatch to Assay office in Sheffield.

Assaying and hallmarking is necessary because when jewellery is manufactured precious metals are not used in their pure form, as they are too soft.

Gold, silver and platinum are always alloyed with copper or other metals to create an alloy that is more suitable to the requirements of the jeweller. Such an alloy needs to be strong, workable, yet still attractive. The assay office tests the (assay) of precious metal goods.

In the UK it is illegal to sell items as gold, silver or platinum unless they have been tested and hallmarked by an assay office.

There are some exceptions, notably items coming in from countries with which they have signed an International Convention 1976.

Since 1st January 1999, the UK also accepts some equivalent European marks without the need for further testing. At present these include Denmark, Finland, Ireland, Portugal and Sweden, plus some Spanish marks.

Otherwise, imported goods must be hallmarked. Some small items may be exempt from hallmarking but must still be up to standard.