To read the full version of this content please select one of the options below:

Entry‐level RP machines: how well can they cope with geometric complexity?

Eujin Pei (Vaal University of Technology, Vanderbijlpark, South Africa)
R. Ian Campbell (Vaal University of Technology, Vanderbijlpark, South Africa)
Deon de Beer (Vaal University of Technology, Vanderbijlpark, South Africa)

Assembly Automation

ISSN: 0144-5154

Article publication date: 12 April 2011



The purpose of this paper is to examine the limitations of entry‐level rapid prototyping (ELRP) machines when fabricating objects with high complexity.


The literature review provides an overview of RP technologies, followed by a discussion on the different levels of complexity in objects. The paper continues with a discussion on the definition of ELRP, followed by a number of experiments to explore the limitations of an ELRP system when fabricating complex models, and to compare the results obtained with those from a professional RP machine using standardised build parameters and the same acrylonitrile butadiene styrene material.


Of the five complex models that were produced from the Rapman machine, four of them were affected by warping; also, support structures were difficult to remove due to the interwoven build pattern. The study also found that the Rapman parts were coarsely built as opposed to the Dimension parts that were less coarse. The Rapman parts were also much lighter due to the hollow internal structure, as compared to the dimension parts that were virtually solid. From a quantitative viewpoint, parts produced from the Rapman machine showed significantly greater average errors in both absolute and percentage terms.

Practical implications

Users should bear in mind the restrictions of ELRP machines when fabricating complex shapes. The models may be prone to warping and the support structures could be difficult to remove.


This paper allows developers to understand the restrictions when fabricating complex models on an ELRP machine. The findings will also enable manufacturers to develop better entry‐level systems.



Pei, E., Ian Campbell, R. and de Beer, D. (2011), "Entry‐level RP machines: how well can they cope with geometric complexity?", Assembly Automation, Vol. 31 No. 2, pp. 153-160.



Emerald Group Publishing Limited

Copyright © 2011, Emerald Group Publishing Limited