Optimal Strategies for Filament Orientation in Non-Planar 3D Printing

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Good work has been carried out by the authors. Few more recent references can be added

Author Response

We greatly appreciate your kind comments and suggestions. We are pleased to know that the work carried out has been to your liking

Comments 1: Good work has been carried out by the authors. Few more recent references can be added

Response 1: In response to your suggestion, we have added 19 recent references, which are reflected in the references section, from line  708 to line 743 (page 18). We deeply value your valuable input and remain at your disposal for any further recommendations.

Reviewer 2 Report

Comments and Suggestions for Authors

This article presents a methodology for generating the trajectories for planar and non-planar layers based on the contours from the level set functions. After a mathematical approach on nonplanar and planar tool path generation, adjustment velocity and material flow, generating G-code for 3D printing, material extrusion on nonplanar layers was made using a 3-axis machine combined with the trajectory parametrization algorithm. It was also presented comparisons of printed parts at an inclination angle with layers generated using the authors’ methodology and planar position obtained using a commercial slicer; comparisons of printed samples at different filament orientation angles.

 

The article will be more useful for the readers in case of implementation of the following improvements:

 

- It is better to use impersonal mode when you write an article.  My recommendation is not to used first plural person (“we” and “our”). I suggest rewriting the sentences with the words “we” and/or “our”;

- For a good visibility in the international databases, the abstract of the paper could be rewritten, not more than 200 words, to have the following information: background, problem statement, approach, results and conclusions;

- Keywords section could be rearranged as follows: “Additive manufacturing; FDM, non-planar printing trajectory; parametrization; STL; G-Code;

- Renumber the references in order of citations in the article;

- At the end of the subsection “1.1. Literature Review” is better for the readers to have the information of the article structure. Update the lines 208-210 according to the sections of the article;

- Figures 1 and 2 are too small. It is not possible to see all the details. Resize and add measuring units on axis;

- Add the measuring units for values from Table 1;

- In the title of the paper (“Optimal Strategies for Filament Orientation in Non-Planar 3D Printing”) you use the term “Optimal” and also in the abstract and the paper. In the body of the paper is not clear how the strategies are optimized.  In sentences from lines 456 – 461 and 472-473, are used the term:“optimal configurations” and “optimize quality”. Are the configurations and quality optimized? What are the values of manufacturing parameters for optimal quality determined?

- In different places of the paper text is used the term “surface quality”. How do you appreciate/measure the “surface quality/quality of the piece” when your affirmations are: “lowest surface quality” (line 447), “significant deficiencies in surface quality” (437) and “without compromising the quality of the piece”?

- Please, give more details on how the methodology was practically validated. It is needed for the readers to have more details (technical information) about the 3D printer used for manufacturing the parts and it will be useful to have relevant pictures from the printing process; Also, give more details regarding the filaments (incl. properties) used for manufacturing the samples presented in the article;

- For printed parts from figures 6 and 7, please, present in the paper text what are the manufacturing parameters their values and/or the interval of variations of them; Are they the same for all the samples;

- Detail in the article why is important the study (including the obtained results), for the industrial environment;

- In my opinion, for an article, a separate “Conclusion” section offers to the readers valuable information about research; Here the novelty of the research has to be emphasized; This section could include the Future research; To add a separate “Conclusion” section could improve the article quality.

- To demonstrate that you have a current literature review, more relevant references, especially from the last three years, must be added.

Author Response

We sincerely appreciate your kind words and valuable feedback. In response to your suggestion, we have revised the article to clearly present the methodology for generating planar and non-planar trajectories, including the mathematical approach, G-code generation, and comparisons of printed parts at various angles. Your insights have significantly improved the clarity of the presentation.

Comment 1:   It is better to use impersonal mode when you write an article.  My recommendation is not to used first plural person (“we” and “our”). I suggest rewriting the sentences with the words “we” and/or “our”;

Response 1: Thank you for your valuable suggestion. In response, all sentences that previously used the first-person plural ("we" and "our") have been rewritten in the third person, in line with your recommendation to maintain an impersonal tone throughout the article. 

Comment 2:  we have revised the abstract to include the conclusions and results of the study, while ensuring it remains under the 200-word limit. This adjustment aims to provide a clearer overview of the background, problem statement, approach, results, and conclusions, as recommended (line 10 to 24). 

Response 2:  we have revised the abstract to include the conclusions and results of the study, while ensuring it remains under the 200-word limit. This adjustment aims to provide a clearer overview of the background, problem statement, approach, results, and conclusions, as recommended (line 10 to 24). 

Comment 3:  Keywords section could be rearranged as follows: “Additive manufacturing; FDM, non-planar printing trajectory; parametrization; STL; G-Code;

Response 3: Your proposed rearrangement of the keywords is very accurate, as the order of keywords plays an important role in guiding the reader’s understanding and enhancing the accessibility of the publication. We have adopted your recommendation and adjusted the order of the keywords accordingly (line 25).

Comment 4:  Renumber the references in order of citations in the article;

Response 4: The references in the manuscript are already numbered in the order in which they are cited within the text.

Comment 5:   At the end of the subsection “1.1. Literature Review” is better for the readers to have the information of the article structure. Update the lines 208-210 according to the sections of the article.

Response 5: In response, the structure of the article has been included in lines 23 to 45, providing readers with a clear overview of the sections (line 221 to 228).

Comment 6:  Figures 1 and 2 are too small. It is not possible to see all the details. Resize and add measuring units on axis;

Response 6: Figures 1 and 2 have been resized to improve visibility, and measuring units have been added to the axes as suggested (line 296 and line 250).

Comment 7:  Add the measuring units for values from Table 1;

Response 7: In response, the units for the values in Table 1 have been added to ensure clarity and precision. We appreciate your attention to detail and your helpful feedback (line 443).

Comment 8:   In the title of the paper (“Optimal Strategies for Filament Orientation in Non-Planar 3D Printing”) you use the term “Optimal” and also in the abstract and the paper. In the body of the paper is not clear how the strategies are optimized.  In sentences from lines 456 – 461 and 472-473, are used the term:“optimal configurations” and “optimize quality”. Are the configurations and quality optimized? What are the values of manufacturing parameters for optimal quality determined?

Response 8: To address your concern, additional information has been added in the discussion section to clarify how the strategies are optimized. Specifically, details regarding the optimization process of configurations and quality have been provided. (line 520 to 532)

Comment 9:  In different places of the paper text is used the term “surface quality”. How do you appreciate/measure the “surface quality/quality of the piece” when your affirmations are: “lowest surface quality” (line 447), “significant deficiencies in surface quality” (437) and “without compromising the quality of the piece”?

Response 9: To clarify the statements made regarding "surface quality" and "piece quality," detailed information has been added in the discussion section of the article. (line 520 to 532)

Comment 10:  Please, give more details on how the methodology was practically validated. It is needed for the readers to have more details (technical information) about the 3D printer used for manufacturing the parts and it will be useful to have relevant pictures from the printing process; Also, give more details regarding the filaments (incl. properties) used for manufacturing the samples presented in the article;

Response 10: A section titled "Material Properties" has been added, detailing the characteristics of the filaments used. Additionally, the applied printing parameters are included in the results section (line 410 to 422 and line 453 to 459 )

Comment 11:  For printed parts from figures 6 and 7, please, present in the paper text what are the manufacturing parameters their values and/or the interval of variations of them; Are they the same for all the samples;

Response 11: In response, the manufacturing parameters, including their values and intervals, have been added in Section 3, "Results," from lines 452 to 457. This ensures clarity regarding the conditions under which the parts in Figures 6 and 7 were fabricated.

Comment 12:  Detail in the article why is important the study (including the obtained results), for the industrial environment;

Response 12: In response, we have added a detailed explanation in Subsection 4.3 regarding the potential applications of our methodology in the industrial environment, including its relevance and the importance of the obtained results (line 604 to 615). 

Comment 13:  In my opinion, for an article, a separate “Conclusion” section offers to the readers valuable information about research; Here the novelty of the research has to be emphasized; This section could include the Future research; To add a separate “Conclusion” section could improve the article quality.

Response 13: Your opinion is absolutely correct, as having a separate "Conclusion" section makes it much easier for readers to understand the significance and results of the research. In light of your suggestion, we have created a new "Conclusion" section where the novelty of the study is emphasized, and directions for future research are outlined. (line 573 to 593)

Comment 14:  To demonstrate that you have a current literature review, more relevant references, especially from the last three years, must be added.

Response 14: In response, 19 more recent references, primarily from the last three and five years, have been added to ensure the literature review reflects the most current and relevant research. (line 706 to 743 )

Reviewer 3 Report

Comments and Suggestions for Authors

First of all congratulations to the authors for the studies and conclusions in this article. For a better understanding of the research carried out, please take into account the following observations and recommendations:

- The abstract should also contain some conclusions/results to increase interest in reading the article;

- you used 2 chapter titles that actually represent the same thing (Introduction and Literature Review) creates a bit of confusion so I think it is recommended to have only one chapter title (especially since you noted 1.1 Literature Review but 1.2 doesn't even exist);

- in chapter 2. Materials and Methods talks about the method but not about the materials used, except for one table (Table 1);

- please specify the type of 3D printer you used (maybe I missed it);

- Congratulations on the Study limitations chapter, I think it is even more important than the conclusions of this study.

 

Author Response

We sincerely appreciate your kind words and valuable comments. 

Comment 1:  The abstract should also contain some conclusions/results to increase interest in reading the article.

Response 1: we have modified the abstract to include the conclusions and results of the study, in order to provide a more comprehensive overview (line 10 to 24)

Comment 2: You used 2 chapter titles that actually represent the same thing (Introduction and Literature Review) creates a bit of confusion so I think it is recommended to have only one chapter title (especially since you noted 1.1 Literature Review but 1.2 doesn't even exist);

Response 2: You are absolutely right, the use of both "Introduction" and "Literature Review" as separate chapter titles was redundant and could cause confusion. In response to your comment, we have removed section 1.1 and streamlined the structure accordingly. 

Comment 3: In chapter 2. Materials and Methods talks about the method but not about the materials used, except for one table (Table 1);

Response 3: You are correct that Chapter 2, "Materials and Methods," primarily focused on the method without providing sufficient detail on the materials used, aside from Table 1. In response to your suggestion, we have added a new subsection titled "Material Properties" in Section 2, where we highlight the properties and characteristics of the materials, as well as the recommended ranges of printing parameters for optimal results. (line 409 to 422)

Comment 4: Please specify the type of 3D printer you used (maybe I missed it);

Response 4: You did not overlook it; the information has indeed been included. Specifically, the methodology was validated using an Ender 3 3D printer, and this detail has now been added in the revised version of the publication in line 362 to 365

Comment 5: Congratulations on the Study limitations chapter, I think it is even more important than the conclusions of this study.

Response 5: Thank you very much for your kind words and thoughtful feedback. 

Reviewer 4 Report

Comments and Suggestions for Authors

 

• What is the main question addressed by the research?

The present study proposed a new slicing approach for fused deposition modeling (FDM) that generates non-planar paths and allows for parametric adjustment of filament direction, improving print quality and the structural integrity of parts.

• Do you consider the topic original or relevant to the field? Does it address a specific gap in the field? Please also explain why this is/ is not the case.

The topic is original since there are some studies in scientific literature that focuses on non-planar slicing, this study outlined a method that parameterizes filament direction across both planar and non-planar layers

• What does it add to the subject area compared with other published material?

As stated in the previous comment, the existing literature lacks a robust mathematical algorithm for producing planar and non-planar slices for parts with complex external and internal features.

• What specific improvements should the authors consider regarding the methodology? What further controls should be considered?

The methodology and how is presented in the article is good enough. They showed how planar and non-planar surface slices can be generated mathematically and then how these slices can be turned into G-codes by including print speed. They also validated this method by method with experiments. One problematic thing is that the similarity report shows that the similarity is very high (20%), normally this is an unacceptable high similarity from my perspective. But if the “Processes” accepts this similarity, then there is no  problem.

• Are the conclusions consistent with the evidence and arguments presented and do they address the main question posed? Please also explain why this is/is not the case.

Yes, the methodology and results are consistent with the initial question of the article (Can both planar and non-planar slicing and printing increase the surface quality?). The authors very clearly presented the results in Results and Discussion section. They also highlighted the limitations and future studies.

• Are the references appropriate?

They are appropriate but a bit old-dated. I would recommend using more up-date references

• Any additional comments on the tables and figures.

No, Table and Figures are enough, readable and understandable.

 

• English quality and typos.

English quality is fine, I didn’t find any mistakes. However, there are some very small typos, please correct them.

• Page 5, Line 240: “Traditionally, the FM process begins…”. FM should be FDM
• Page 11, Line 416: “In Figure 6 presents…” Delete “In”
• Page 12, Line 44: “In Figure 7, Are present…” Please change it as “Figure 7 presents…”

 

Author Response

We deeply appreciate the comments, which have provided us with valuable feedback. We also thank you for your positive evaluation of our methodology and the experimental validation presented in the article. We take into account your recommendation regarding the update of references and the writing corrections.

Comment 1: They are appropriate but a bit old-dated. I would recommend using more up-date references

Response 1: In response, 19 more recent references on the topic have been included to ensure the literature cited reflects the latest advancements in the field. We appreciate your suggestion to improve this aspect of the article. 

Comment 2: 

English quality is fine, I didn’t find any mistakes. However, there are some very small typos, please correct them.

Page 5, Line 240: “Traditionally, the FM process begins…”. FM should be FDM
Page 11, Line 416: “In Figure 6 presents…” Delete “In”
Page 12, Line 44: “In Figure 7, Are present…” Please change it as “Figure 7 presents…”

Response 2:

The suggested corrections have been made as follows:

Page 5, Line 261: "FM" has been changed to "FDM."
Page 11, Line 488: The extra "In" has been removed.
Page 12, Line 462: The sentence has been corrected to "Figure 7 presents..."

I appreciate your attention to detail.

 

 

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors answered to all my comments/recommendations.