REPORTE DE FALLAS (ATENCIÓN DE QUEJAS Y RECLAMOS)

5.6.1 In-House or Outsource

As with any process that requires capital investment, operational overhead, and staffing, the first decision is to choose between acquisition and operation of a rapid prototyping system and out-sourcing the work to a qualified service bureau. The justification for either approach will be made with consideration of system utilization, expected benefits, and total expense.

Rapid prototyping can be difficult to evaluate since there is a limited body of publicly available information. This is most evident when trying to determine the cost of operation and limitations of the technology. With dozens of available systems and limited information, it can be challenging to select the most appropriate for the current needs. For this reason, many companies elect to use ser-vice bureaus prior to a system purchase. The use of the serser-vice bureau allows the evaluation of mul-tiple technologies and materials with minimal risk. It also establishes a baseline upon which financial projections can be made.

Should the implementation of a rapid prototyping system be justified, many find that they still require outsourced prototypes to support users’ demands. There are three reasons for this outsourc-ing strategy. First, it is not economically sound to have the available capacity to meet peak demands.

Doing so means that on most days the system will be idle or underutilized. In this case, the service bureau is used to provide capacity when demand outstrips supply. Second, for some rapid prototyp-ing systems, carryprototyp-ing multiple materials can be expensive, and material conversion can be time con-suming. Rather than bearing the expense of carrying all possible materials and impacting efficiency

and productivity with downtime for conversion, parts are outsourced when desired material properties cannot be satisfied with the in-house material inventory. Third, it is unlikely that one technology can address all applications. It is best to implement a technology that addresses the majority of the demands while outsourcing the balance of work to service bureaus that possess the desired alterna-tive technologies.

5.6.2 Implementing Rapid Prototyping

Independent of the decision between in-house operations or outsource purchases, there are key ele-ments to the successful application of rapid prototyping. Like any other manufacturing technology, a strong operation is built upon education, organization, process, measurement, and management.

Without these elements, the full impact of the technology will not be realized.

Beyond training, processes, and management, an in-house implementation of a rapid prototyping system has three areas of consideration: front-end systems, rapid prototyping systems, and back-end operations.

5.6.3 Technology Implementation

Front-End Systems. To deliver the speed and responsiveness expected of rapid prototyping, the implementation of front-end systems must address both process and computing needs. The areas that are addressed are the receipt, management, and processing of data for the rapid prototyping builds.

Rapid prototyping is fast-paced and subject to frequent change. Therefore, a process to coordi-nate, manage, and schedule the operation is vital. The schedule will be dynamic, often changing many times a day. So, a process for submitting work and managing the schedule needs to be devised.

Also, multiple revisions to each part’s design should be expected, and this requires a strategy for revision control and data archival needs to be developed.

The installation of front-end systems is relatively straightforward, where many elements are com-mon to other information technology (IT) projects. Dependent on typical part size, STL files can get quite large, so it is important to establish a local area network that can transmit large files rapidly. It is also important to consider wide area network demands if data will originate from outside the rapid prototyping operations facility. This would require an FTP server with large bandwidth.

Checklist of implementation elements:

䊊 Data communications 䊊 Data preparation

䊐 FTP communications 䊐 STL generation

䊐 Local area network 䊐 File processing

䊐 Computer servers and workstations 䊊 Scheduling

䊊 Data handling 䊐 Order receipt

䊐 Revision control 䊐 Job scheduling

䊐 Archival 䊐 Order confirmation

RP Systems. Implementing the hardware for a rapid prototyping operation requires some advanced planning. Prior to the delivery of the system, facility modifications are often required. Most rapid prototyping systems are best suited to a controlled lab environment, not the shop floor or the office area. In constructing the lab, considerations include HVAC, isolation from (or for) airborne contam-inants, and electricity. For some systems, supply lines for gases or water may also be required. Also allot space for material inventory, tools, and supporting equipment in the lab.

Prior to the installation, practices and procedures should be created for material storage, handling, and disposal. For those materials that are not treated as hazardous, the procedures may focus only on proper handling, disposal, or reclamation of materials. For systems that use materials that are con-sidered hazardous, employee safety procedures should be created and corporate policies and gov-ernmental regulations should be reviewed.

In all cases, the equipment vendor will be an important information source for facility, safety, and equipment requirements. This information will be offered in advance of system delivery so that the facility is ready for the installation.

Checklist of implementation elements:

䊊 Facilities 䊊 Maintenance

䊐 Space allocation and modification 䊐 Routine preventative maintenance

䊐 Electricity 䊐 Routine system calibration

䊐 Uninterruptible power supplies 䊐 Repairs

䊐 Environmental control (HVAC) 䊊 Materials

䊐 Ventilation 䊐 Material selection (may be third party)

䊐 Isolation of airborne contaminants 䊐 Inventory control

䊊 Installation 䊐 Waste disposal

䊐 Set-up 䊊 Safety

䊐 Calibration 䊐 Equipment (gloves, respirators)

䊐 Testing 䊐 Handling and operation procedures

Back-End Operations. The post-build requirements of the rapid prototyping systems vary greatly.

However, the one common element is that no technology produces a part that is ready for use directly from the machine. In general, there are two components to consider during the implementation, cleaning, and benching.

The considerations for back-end operations are similar to those for any model shop environment.

In fact, if a model shop exists, the implementation may require only the addition of a few pieces of specialized equipment.

Rapid prototypes require cleaning after being removed from the system. For most processes, this entails removal of excess material (resin or powder) that coats the part’s surface and the removal of support structures. The system vendor will recommend the appropriate equipment, which may include part washers, solvent tanks, or downdraft tables.

Benching is the most labor-dependent operation in the rapid prototyping process. For every sys-tem, supplying a prototype, pattern, or tool with the desired level of finish will require some degree of benching. This process will require facility modification for workstations, solvent baths, debris isolation, and possibly paint booths. Additionally, an inventory of supplies and tools will be needed.

These operations generate waste and contaminants, so thought should be given to the disposal of wastes (some considered hazardous), safety, and isolation of airborne contaminants.

Checklist of implementation elements:

ⵧ Solvent tanks 䉯 Waste hauler

ⵧ Hand tools 䉯 Procedures

ⵧ Downdraft tables ⵧ Regulatory controls

ⵧ Paint booths 䊊 Safety

ⵧ Shop equipment ⵧ Equipment

䉯 Mills, drills, lathes 䉯 Gloves

䊐 Bead blaster 䉯 Safety glasses or shields

䊐 Ovens 䉯 Respirators

䊊 Supplies 䊐 Handling and operation procedures

䊐 Consumables

䉯 Adhesives

䉯 Solvents and other chemical agents