Paramount PDS Paramount PDS

Rapid Prototyping

Paramount uses two RP technologies to support it,s product development assignments. RP, also know as SFF (Solid Freeform Fabrication) is a layer by layer fabrication process. A three-dimensional computer model of a part is sliced into layers by the RP systems computer program. Each slice is fed to a processor which in turn directs a laser in X and Y axis directions, as well as controlling the beam output strength, to cure or sinter through either UV laser (SLA) or CO2 laser (SLS) the cross section (slice) of the part. After the slice is completed the system's build mechanism vertically repositions incrementally (Z vector), usually between .07mm and .15mm per layer. This process is repeated until the vertical height of the part is completed.

SLS (Selective Laser Sintering) and SLA (StereoLithography Apparatus) have proven invaluable as aids in the rapid development of products. There are virtually no industries, including medicine, that have not realized the benefits of these technologies. If time is money, then time compression wherever possible, is critical to your business. The opportunities are far reaching well beyond prototyping. Manufacturing, whether its tooling to produce parts, or patterns to produce multiple parts have just begun to embrace RP. Clearly those systems that are visionary will be those that best fit real manufacturing needs.

Paramount began using rapid prototypes in 1989 to augment its product development process. After recognizing the future potential, rather than purchase a system early, we chose to embrace and learn 3D CAD/CAE solid modeling design tools. In 1990, we acquired two seats of SDRC I-DEAS. We monitored the progress of SLA and other emerging RP systems carefully. As a design engineering/product development company using 3D solid modeling, we were customers as well as suppliers of these processes. In 1994-95, improved quality was apparent, both dimensional and surface finish. These attributes were best realized using SLA. In 1991, DTM Corporation introduced Selective Laser Sintering (SLS). After careful evaluation of the marketplace, we purchased our first SLS Sinterstation 2000 in 1996. The decision was made because of the wide range of powder materials available to SLS. Our initial decision was based on RapidSteel 1.0. Knowing that there were nylon and polycarbonate powders available only strengthened our decision. In 1997, we acquired a rapid prototyping service bureau in southeast Pennsylvania, acquiring our second SLS 2000. In 1998, we purchased an SLS Sinterstation 2500plus.

As experts in model making, pattern making and mold making we understand prototype model quality and accuracy. Our knowledge of manufacturing processes gives us a unique advantage to leverage both SLS and SLA for their individually unique application characteristics. SLA emerged as the industry leader in form, fit and appearance applications. SLA still demands the leading position when it comes to holding close tolerances (<.07mm) and smooth surface finish. Its material properties are limited where robust or demanding performance situations are present. Stereolithography (SLA) is a UV curable epoxy resin base system. Because it is an epoxy resin system there are self-imposed practical limits to prototyping and manufacturing applications. Frequently, parts that are produced from SLA are transferred to urethane castings using silicone rubber molds (RTV - Room Temperature Vulcanization). The urethane castings are used in the customer's application. SLS materials are suited for direct functional applications where performance demands robust resistance from chemical, heat, wear, abrasion, flexibility, and internal/external surface pressures.

Paramount's RP sales associates, after consulting with you and understanding your RP application, will help you select the most appropriate RP process. If functional prototypes, rapid metal parts, concept-bridge tools or prototype injection molds are required, our team of professionals can offer an SLS solution that best meets your needs. We offer you a free download of Adobe Acrobat PDF Reader TM and a free download of DTM's SLS material mechanical properties sheets. If you need an SLA master to make a rubber mold, Paramount can project manage the purchase and offer you a turnkey solution. We measure ourselves by the value we add to our clients and their projects.

SLS Rapidsteel Technology & Process Overview:

DTM introduced metals in 1995. Their original material RapidSteel 1.0 was a composite of 1080 steel and copper. In 1998 DTM commercialized RapidSteel 2.0. The material is a fine powder 40-50 microns in diameter. RS2 powder represents a 40% improvement in surface roughness and fineness of part features. It is processed in DTM's sinterstation. The metal powder (316L stainless steel and bronze) is mixed with a polymer binder system. The laser solidifies the binder one slice at a time forming the part.

The metal powder is suspended in the binder. This step is commonly referred to as the green part. Build times vary depending upon the particular model sinterstation you are operating. The new 2500plus with a 100-watt laser is 240% faster then the model 2000. Next the green part is placed into a crucible, packed in a course alumina powder to be sintered at 1120c for 24 hours. This part is referred to as a brown part. After sintering infiltration tabs are placed adjacent to the brown parts. Bronze pellets or bars are then stacked. Fine alumina powder is placed around the part and tabs to direct molten bronze to the sintered parts being infiltrated. The crucible is again placed in the furnace to be infiltrated at 950c. This completes the SLS process. The mold insert or part is now ready for secondary machining and finishing operations.

Products & Services:

RP Applications:

Materials:

For Your convenience SLS material properties sheets can be downloaded from our web site. To read the PDF files you will first need to download Adobe's Acrobat Reader 4.0 from the Adobe website. After you've downloaded Acrobat Reader, select a material properties sheet by clicking on the applicable PDF file to begin the download.

The Tools We Use

Software

Machinery and Equipment

Rapid Prototyping Success Story:

Volvo Penta

DTM, RapidSteel, Somos, DuraForm, CastForm PS, Sinterstation, and SLS, Selective Laser Sintering are registered trademarks of DTM Corporation.