Renfert GEO medium wax casting sprue blue – dental casting system
Référence: 678.3020
Renfert medium-hard wax sprue wire for precise casting networks
The Renfert medium-hard wax sprue wire is designed to create regular, stable and easily adaptable casting channels in the dental laboratory.
Its GEO formulation provides stress-free handling with low restoring forces, helping to reduce deformation during sprue network preparation and investment.
Renfert casting wax for bridges, frameworks and cast prosthetic elements
In dental prosthetics, the quality of the casting network directly influences metal feed regularity, restoration stability and the reduction of defects after casting. This medium-hard wax sprue wire helps build clean, progressive and reproducible channels while maintaining excellent stability during handling.
Its blue colour makes it easier to check thicknesses and connections before investment. It fits easily into casting protocols for crowns, bridges, frameworks, metal partial denture structures and laboratory work requiring a precise sprue network.
Laboratory benefits
- Medium-hard wax: good balance between shaping flexibility and positional stability.
- Low memory: limits elastic rebound after shaping.
- Stress-free handling: improved network stability before investment.
- Clean cutting: easy length and connection adjustment.
- Blue colour: quick visual reading of channels, sections and joints.
Dental applications
- Creation of main and secondary casting channels.
- Preparation of networks for crowns, bridges and metal elements.
- Fixed prosthetic work requiring regular metal feeding.
- Mounting sprue wires on wax patterns before investing.
- Creating progressive connections to reduce casting turbulence.
How to choose and use a medium-hard wax sprue wire correctly
Preparing the casting network
- Cut the required length with a clean, suitable instrument.
- Position the sprue wire according to the desired casting axis.
- Avoid excessive tension during shaping.
- Slightly warm the connection areas to obtain a clean bond.
Before investment
- Check the continuity of the main and secondary channels.
- Avoid sharp angles that may disturb metal flow.
- Make sure the sections remain consistent throughout the network.
- Stabilise the assembly before placing it in the investment ring.
Laboratory tip
Renfert documents & resources
Technical specifications
| Product | Medium-hard wax sprue wire |
|---|---|
| Brand | Renfert |
| Reference / SKU | 678.3020 |
| Range | GEO wax for dental laboratory work |
| Consistency | Medium-hard |
| Colour | Blue |
| Packaging | 250 g roll |
| Indication | Creation of casting channels and networks for prosthetic elements |
| Diameters | Several diameters available according to laboratory requirements |
Complementary products for wax work
Delivery
Supplied as one Renfert medium-hard wax sprue wire roll, blue colour, 250 g packaging — diameter of your choice.
FAQ — Renfert medium-hard wax sprue wire
Why choose medium-hard wax for sprue wires?
Medium-hard wax provides a good compromise between flexibility and stability.
It can be bent, cut and connected easily while maintaining enough hold during casting network preparation.
For the dental laboratory, this stability is important to reduce unwanted movement before investment.
It allows clean work on both main and secondary channels, with better control of the final shape.
Does the blue colour have a technical advantage?
Yes, the blue colour makes visual control of the casting network easier.
It helps distinguish the sprues, connections and sections on the wax pattern.
This contrast is useful for checking thicknesses, identifying areas that are too thin and verifying channel continuity before investing.
In the laboratory, this quick reading improves safety and consistency during casting work.
How can tension be avoided in the casting network?
It is recommended to shape the sprue wires progressively, without excessive twisting.
Connections should be made with slightly warmed wax to obtain a clean, homogeneous and bubble-free joint.
Sharp angles should be avoided, as they can disturb metal flow.
A well-balanced network, with smooth curves and suitable sections, promotes more regular casting and helps reduce defects after casting.
Is this sprue wire suitable for bridges and frameworks?
Yes, this Renfert sprue wire can be used to prepare networks for bridges, crowns, metal elements and frameworks according to the laboratory protocol.
The diameter should be selected according to the metal volume, pathway length and complexity of the piece.
For extended work, progressive feeding is recommended to obtain a more homogeneous casting result.
How should casting wax be stored in the laboratory?
Store the roll at room temperature, away from direct heat, dust and sources of deformation.
Wax that is too warm may become too soft and lose precision during handling.
Conversely, wax that is too cold may be less pleasant to shape.
Clean and stable storage helps maintain good handling properties and consistent quality for laboratory work.
Renfert GEO medium wax casting sprue blue – dental casting system