The much awaited release of the Italian made Digital Wax Systems 3D Printer will be held in Tucson at the Rio Grande Catalog In Motion on February 5- 8th. The CAM systems being introduced are compatible with all CAD software and provide wax patterns with a superior surface finish designed for investment casting.
I recently visited Rio Grande and met with the owner of DWS who invented and manufactures the laser based printers in Vicenza, Italy. The technology is mature and has been used in Europe and the far-east for several years where it is marketed exclusively to the jewelry industry. Rio Grande is now the North American distributor who will provide all training and full technical support.
DWS manufactures three models of 3D printing machines based on laser solidification of UV photopolymers. The system design is a hybrid of both the familiar EnvisionTec and the 3D Systems SLA technologies.
Patterns are developed from a shallow optical glass tray which contains a minimum amount of polymer. Each solidified layer of the process is peeled from the tray by an elevator platform after solidification by a laser plotting from beneath the tray. Peel is also assisted by an elastic membrane layer within the material tray. This membrane is a distinct advantage over other technologies as it requires fewer and smaller supporting structures for the build process.
All three machines can build models in a layer thickness ranging from 0.01 – 0.05 mm in the Z axis depending on resin type. These materials however seem to be optimized by the manufacturer for 0.03 mm layers. Support generation is expected to be performed primarily in the native CAD software.
The DWS 008 model is an entry level machine with a 65 x 65 mm envelope which can produce on average 4 – 6 models per day. The curing process is performed by a diode laser affixed to a carriage on a gantry beneath the tray.
The plotting of the carriage is performed by rotary encoders driven by belts and pulleys. The gantry system allows for the laser curing spot to remain very constant in shape although it does increase build time significantly over the other two DWS models. The plotting style is drawn in a single line raster with user defined hatching based on the design geometry in a range from 0.02 – 0.06 mm. There is, unfortunately, no plotting of the design perimeter to optimize surface quality and no Z compensation preparation software included. Users must supply a SLC file type with supports generated by a third party program or native CAD software.
The DWS028 model also has a 65mm x 65 mm envelope which can produce 30-40 models per day. The curing is performed by a fixed laser diode which uses a movable mirror array to plot the curing process. The plotting style is raster like the DWS008 but also includes a final vector plot of the model perimeter on each layer which improves surface quality. The raster hatch range is also greater from 0.01 – 0.09 mm. The DWS028 comes with a software suite which can provide for Z compensation and thus a slightly more accurate result. Users can supply either an SLC from a third party / native CAD or an STL file which can be converted to SLC after Z compensation is performed. This software suite seems to be much more robust and provides repair and Boolean Union of created primitive STL supports. The diode laser used on DWS0028 is less powerful than the other two DWS models and thus users are constrained to the DWS400 polymer material for investment casting. Look for a new resin that we tested last month to be l released in Q1 of 2010 with a remarkable surface finish
The DWS029 model is similar in construction to the DWS028 with a few exceptions. The build envelope is 110 mm x 110 mm and thus the throughput is significantly higher in excess of 100 designs per day. The laser is also a higher output than the DWS028 so the DWS500 resin can be used. This resin seems to cast somewhat easier than the DWS400 used on the DWS028 machine. All software and firmware supplied on the DWS028 is also provided for the DWS029.
Given the apparent quality of these products and the reliability of experienced customer service from Rio Grande, this system is well worth your time and interest in Tucson or other trade shows this year. We are currently testing the castability of these new resins here at Techform and I will report our results here on JCKOnline next month.