GALLERY

Double Technology Company in Hong Kong is a succesfull reseller of DeskProto in Hong Kong and China. Their combination of the JewelCAD design software, the DeskProto CAM software and a desktop Roland Jewela milling machine proves to make an excellent total system for jewellers.

Double Technology offers more than just a combination of these standard solutions: proprietary hardware and software is added, that enables the machining of very complex wax models for rings.
For inquiries about this system please contact Double Technology.

The sketch of the desired ring, that was created by the client and used as basis for the CAD work.

This project has been realized by Double Technology as benchmark for Hong Kong based jeweller Gin Jewellery Ltd.. As the resulting ring has indeed been manufactured, the project qualifies for display on the DeskProto Gallery.

Start of the project was a hand drawn sketch from the client. Based on this sketch Double Technology's service team created the 3D model and next machined and finished the wax model. The actual manufacturing of the ring has been done by the client.

Left, right: Renderings of the final design in JewelCAD.

As said the ring geometry has been modelled in JewelCAD, Version 5.1. This CAD program is meant only for jewelry design, and offers a wide range of tools and options for jewellers. One of the tools is a high quality rendering output: ideal for presenting the design to the client.

After the client's approval an extra "core" is added at the inside of the ring, to be used with Double Technology's special ring machining fixture described below. The resulting combined CAD model then is exported as an STL file.

Left, right: Rotation axis toolpaths in DeskProto.

Based on this STL geometry the toolpaths have been calculated in DeskProto, for a very sharp conical cutter in order to also produce the most intricate small details. Three sets of toolpaths have been created: two using DeskProto's Two Sided Milling Wizard, and one using Rotation axis machining.

This machining from several sides makes it possible to create very complex wax models, including many undercuts, on a machine that in theory does not allow any undercuts. As a result the advantages of CNC milling (low cost, high surface quality) are combined with the main advantage of additive manufacturing (model complexity).

Left: two sided machining of the wax model Right: rotation axis machining.

Machining of the wax model has been done on a Roland Jewela machine (model JWX-10). The pictures above clearly show the special fixture for ring machining that has been applied. The Jewela makes it possible to do the two sided machining while the rotation axis unit keeps attached: no need to continuously attach and de-attach this unit.

Different solutions for ring machining fixture are available from other suppliers. Advantage of this Double Technology fixture is that it supports full rotation axis machining: 360 degrees around the complete ring.

The part was cut in green carving wax. The two sided milling was done in approximately 2 hours. Next the rotation toolpath took approximately 30 minutes.

The resulting wax model.

The wax model as it comes from the milling machine is sufficiently smooth for casting: polishing is not needed. Still some manual finishing is required, as the "core" has to be removed from the ring. The places where the bridges connected it to the ring have to be smoothened.

The resulting ring, in platinum-plated silver

The final product has been cast in Silver. Of course after casting manual cleanup was needed to remove the sprues used in casting. The ring also has been polished to get the gloss as shown above, and has been plated with platinum.
After this the stones will be set, and a final polishing will be applied to achieve the high gloss that is required.