Gluing Instructions

Overview of the Gluing Application Processes

When gluing Swarovski Crystals, optimal results are obtained by coordinating the entire application process. Following the application steps in the right order is very important. Experience has shown that the most common reasons for crystals becoming detached are inappropriate areas of application, poorly produced cavities, unsuitable gluing systems, and insufficient quantities of glue. Product-specific application instructions are detailed later in this section.

Gluing Overview


Cavity Production

Many Swarovski crystals require cavities in order to be applied to materials. A properly produced cavity in combination with a suitable gluing system ensures a stylish, long-lasting application. The cavity makes it easy to glue properly and ensures a higher protection of the crystal against mechanical and chemical stress.

There are several different production methods and cavity types. Always take into consideration the requirements and base material of the finished product when choosing the appropriate cavity, pre-treatment method and right kind of glue.

 

Production methods

  • Drilling is when materials are machined using a power drill and drilling tool.
  • Milling is when materials are machined using a milling machine and milling cutter. Milling machines can be fitted with appropriate tools depending on the materials, e.g. for working with metal and plastic, wood or natural stone. Modern CNC machining centers offer the greatest precision and can be used to producecavities of every shape necessary. Please note that when machining natural stone, ceramic or glass, for example, special diamond-tipped tools must be used.
  • Water jet cutting allows materials to be separated via a high-pressure jet of water. Economic reasons make water jet cutting machines ideal for certain crystal shapes that are integrated into flat materials. Please note that only end-to-end cavities can be produced in this way. In addition, materials which swell through water cannot be worked with. Absorbent materials must be fully dried before gluing the crystal.
  • Casting: To reproduce cavities, particularly in the jewelry sector, the cavities can be made when the metal component is cast. When following this process, the cavities must be cut into the original model. To prevent the bottom of the cavity being rounded off, which would result in the crystal sitting too high, it is recommended that an additional indentation is made when producing the original model.

 

Checking Surface Tension and Pre-Treatment

The surface tension is an indicator for the wetting properties of the surface to be glued. A surface tension of at least 38 mN/m is recommended for gluing SWAROVSKI ELEMENTS. It should also be randomly tested during production. 

It is best to use the test pen (Art. 9030/000) to measure the surface tension.

Surface Tension Testing

Note: On porous or absorbent materials, the surface tension cannot be checked with the test pen.

 

Choice of Glue

The selection of the best gluing system is the next stage in ensuring a long-lasting application. When selecting the most suitable glue, the following factors should be considered:

  • The type of cavities/the resulting gluing gap
  • The size of the crystals/gluing surface
  • The gluing properties and finish required
  • The type of base material

 

The type of cavities/the resulting gluing gap

When selecting an adhesive, it is also important to consider the gluing gap that results from the type of cavity chosen. For cavities offering a large gluing gap, soft, gap-filling glues such as silicone glue are recommended, to avoid tension in the glue joint. 

Epoxyethane/polyurethane glues offer greater strength, and can be used for cavities with a small gluing gap.

Gluing Gap

 

 

The size of the crystals/gluing surface

Please note that when gluing small crystals, glues with higher shearing strengths (e.g. epoxy resin glue CG 500-35) should be used. Further information can be found in the manufacturer’s technical data sheets.

 

The gluing properties and finish required

When selecting glues, it is important to consider properties such as pot life, viscosity, color, curing time, ease of dosing and shrinkage.
Further information can be found in the manufacturer’s technical data sheets. 

Adhesives tend to shrink during curing. There will be a greater amount of shrinkage if the wrong glue has been chosen, it is hardened under the wrong conditions or if there is an incorrectly sized cavity (too much space around the crystal). The tension thus created can damage the foiling and the crystals may even detach. Glues that are very hard after curing and shrink considerably are not suitable for Swarovski crystals with foiling.

Gluing  

 

Dosage

The glue can be precisely dispensed via a variety of dosage systems. Dispensers with a vacuum connection prevent the glue from dripping and reduce the amount of cleaning needed. The correct amount of glue will additionally protect the foiling from external influences. Attention must be paid to the application and quantity of the glue.

 

Glue application

Irrespective of the shape of the gluing area, the glue should be applied as follows:

Gluing Area

With a round gluing area, a dot of glue in the centre is sufficient. When the crystal is applied, the glue will be evenly distributed in the gluing gap. To glue a single spot, aim the dispensing needle just above the spot to be glued and lift it slowly upward to avoid any glue spreading out sideways.

Gluing Area 2

 With a square or rectangular gluing area, apply a cross of glue to ensure it is evenly spread into the corners.


Glue quantity

When selecting the amount of glue to dispense, ensure that when setting and pressing down on the crystal, the glue spreads to the edges, thus offering additional protection for the foiling.

Gluing 4


Post Cleaning

Excess glue that escapes during setting can be carefully removed using a cotton wipe that has been soaked in a solvent, e.g. isopropyl alcohol. It must be removed while the glue is hardening, as dried glue cannot be fully removed.
Remember to follow the glue manufacturer’s instructions, as well as considering the resistance of the base material.

 

 

Curing

The curing time of the glue depends mainly on the temperature, or on the humidity in the case of silicone glues. Please note the glue manufacturer’s instructions. To minimize shrinking and tension during hardening, we recommend a maximum curing temperature of 50°C (122°F), with the exception of two-component epoxy resin glue CG 500-35. CG 500-35 can be cured at a maximum temperature of 100°C (212°F), without any changes to its properties.