I've been thinking that we don't pay much attention to the published literature. So I hereby start ... The RepRap Joural Club! Here is one book and two articles about RP which people may find interesting. Forrest's thoughts on them: [3dreplicators.com] Please email me at penguin at supermeta dot com if you want me to email you a copy of one or both articles. I'd attach them as files, but there's a note from the publisher asking that I not do that. The second article, "Conceptual framework for the thermal process modelling of fused deposition", is from the bibliography of this book: "Rapid Prototyping: Laser-Based and Other Technologies" by Patri K. Venuvinod and Weiyin Ma [www.amazon.com] abebooks has it for USD$16.52 [www.abebooks.com] ** [pep.metapress.com] Three-dimensional finite element analysis simulations of the fused deposition modelling process Journal Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture Publisher Professional Engineering Publishing ISSN 0954-4054 Issue Volume 220, Number 10 / 2006 DOI 10.1243/09544054JEM572 Pages 1663-1671 Authors Y Zhang1, Y K Chou1 1Mechanical Engineering Department, The University of Alabama, Tuscaloosa, Alabama, USA Abstract Fused deposition modelling (FDM) is a layer-manufacturing technology that has been widely used for rapid prototyping applications in product design and development. Owing to the intensive energy, rapid cooling, and phase changes, parts made by FDM and other layer-manufacturing processes deviate from the designed geometry, and some require laborious post-processing. Most severe form inaccuracies such as curl, warping, and delamination are attributed to the residual stress accumulations during prototype fabrications. This study investigates the FDM process, which consists of complicated heat and mass transfer phenomena coupled with mechanical loading and phase changes. A finite element analysis model using element activations has been developed to simulate the mechanical and thermal phenomena in FDM and further used for residual stress and part distortion simulations. The model has also been used to study the tool-path effects on the FDM process. Tool-path patterns affect the residual stresses in not only the magnitude but also the distribution which shows stress concentrations aligned with the primary direction of the tool path. Measured prototypes from the experiment show that the part distortion centre shifts distinctly owing to different tool-path patterns, which is consistent with the residual stress characteristics in the simulations. From the simulations, it is also shown that the short-raster tool path results in higher residual stresses, and thus possibly larger distortions, than the long-raster and alternate-raster patterns, both having similar stress distributions and distortion features. Keywords fused deposition modelling, finite element analysis, layer manufacturing, part distortion, residual stress References References secured to subscribers. ** [www.emeraldinsight.com] Title: Conceptual framework for the thermal process modelling of fused deposition Author(s): M. Atif Yardimci, Sel https://reprap.org/forum/read.php?1,10007,10007#msg-10007 Sat, 16 May 2026 16:21:28 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?1,10007,10137#msg-10137 https://reprap.org/forum/read.php?1,10007,10137#msg-10137 Forrest Higgs General Thu, 06 Mar 2008 19:02:32 -0500 https://reprap.org/forum/read.php?1,10007,10136#msg-10136 https://reprap.org/forum/read.php?1,10007,10136#msg-10136
Have you tried building from the outside in?]]> nophead General Thu, 06 Mar 2008 18:16:42 -0500 https://reprap.org/forum/read.php?1,10007,10135#msg-10135 https://reprap.org/forum/read.php?1,10007,10135#msg-10135 Forrest Higgs General Thu, 06 Mar 2008 17:53:06 -0500 https://reprap.org/forum/read.php?1,10007,10134#msg-10134 https://reprap.org/forum/read.php?1,10007,10134#msg-10134
And surprising, I was planning to try starting at the inside and spiraling out as intuitively that would seem better. Each new turn of the spiral has a solid core to resist its shrinkage inwards.]]> nophead General Thu, 06 Mar 2008 17:50:04 -0500 https://reprap.org/forum/read.php?1,10007,10133#msg-10133 https://reprap.org/forum/read.php?1,10007,10133#msg-10133
Sean, on that off topic topic I found this:

"""
The mechanical effects of deposition patterns in welding-bflsed layered manufacturing
Mughal, M.P. (Faculty of Mechanical Engineering, GIK Institute of Engineering Sciences and Technology, NWFP); Mufti, R.A.; Fawad, H. Source: Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture, v 221, n 10, 2007, p 1499-1509
ISSN: 0954-4054 CODEN: PIBMEU
Publisher: Professional Engineering Publishing Ltd.

Abstract: This paper presents a finite element (FE)-based three-dimensional analysis to study the structural effects of deposition patterns in welding-based layered manufacturing (LM). A commercial finite element software ANSYS is used to simulate the deposition incorporating a double ellipsoidal heat source, material addition, and temperature-dependent material properties. Simulations carried out with various deposition sequences revealed that the thermal and structural effects on the workpiece are different for different patterns. The sequence starting from outside and ending at the centre is identified as the one which produces minimum warpage.
"""

Of note is that last sentence in the abstract.

Demented]]> Demented Chihuahua General Thu, 06 Mar 2008 16:45:14 -0500 https://reprap.org/forum/read.php?1,10007,10009#msg-10009 https://reprap.org/forum/read.php?1,10007,10009#msg-10009 Roach_S General Fri, 29 Feb 2008 19:55:39 -0500 https://reprap.org/forum/read.php?1,10007,10007#msg-10007 https://reprap.org/forum/read.php?1,10007,10007#msg-10007
Here is one book and two articles about RP which people may find interesting.

Forrest's thoughts on them:
[3dreplicators.com]
Please email me at penguin at supermeta dot com if you want me to email you a copy of one or both articles. I'd attach them as files, but there's a note from the publisher asking that I not do that.

The second article, "Conceptual framework for the thermal process modelling of
fused deposition", is from the bibliography of this book:
"Rapid Prototyping: Laser-Based and Other Technologies"
by Patri K. Venuvinod and Weiyin Ma
[www.amazon.com]

abebooks has it for USD$16.52
[www.abebooks.com]

**
[pep.metapress.com]
Three-dimensional finite element analysis simulations of the fused deposition
modelling process
Journal Proceedings of the Institution of Mechanical Engineers, Part B:
Journal of Engineering Manufacture
Publisher Professional Engineering Publishing
ISSN 0954-4054
Issue Volume 220, Number 10 / 2006
DOI 10.1243/09544054JEM572
Pages 1663-1671

Authors
Y Zhang1, Y K Chou1

1Mechanical Engineering Department, The University of Alabama, Tuscaloosa,
Alabama, USA
Abstract

Fused deposition modelling (FDM) is a layer-manufacturing technology that has
been widely used for rapid prototyping applications in product design and
development. Owing to the intensive energy, rapid cooling, and phase changes,
parts made by FDM and other layer-manufacturing processes deviate from the
designed geometry, and some require laborious post-processing. Most severe
form inaccuracies such as curl, warping, and delamination are attributed to
the residual stress accumulations during prototype fabrications.

This study investigates the FDM process, which consists of complicated heat
and mass transfer phenomena coupled with mechanical loading and phase
changes. A finite element analysis model using element activations has been
developed to simulate the mechanical and thermal phenomena in FDM and further
used for residual stress and part distortion simulations. The model has also
been used to study the tool-path effects on the FDM process. Tool-path
patterns affect the residual stresses in not only the magnitude but also the
distribution which shows stress concentrations aligned with the primary
direction of the tool path. Measured prototypes from the experiment show that
the part distortion centre shifts distinctly owing to different tool-path
patterns, which is consistent with the residual stress characteristics in the
simulations. From the simulations, it is also shown that the short-raster
tool path results in higher residual stresses, and thus possibly larger
distortions, than the long-raster and alternate-raster patterns, both having
similar stress distributions and distortion features.

Keywords
fused deposition modelling, finite element analysis, layer manufacturing, part
distortion, residual stress
References

References secured to subscribers.

**
[www.emeraldinsight.com]
Title: Conceptual framework for the thermal process modelling of fused
deposition
Author(s): M. Atif Yardimci, Sel]]> SebastienBailard General Fri, 29 Feb 2008 19:00:52 -0500