Most Helpful Customer Reviews
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6 of 6 people found the following review helpful:
4.0 out of 5 stars
Good but only an outline to build your own., 20 April 2007
On the whole this book was excellent, however, it lacked certain details about the build of the authors CNC machine. It was more of a design brief instead of what I was expecting, i.e. a prescriptive build manual. It is though, an excellent starting point especially if you're into taking your time and experimenting with the ideas outlined. The chapters involving the software to drive the CNC machine was excellent, and prescriptive, along with the electronics to drive the stepper motors. A little more detail on stepper motors and the guide rail construction would have been helpful. Some dimensioned drawings would have been useful, but I felt the author was trying to make the design flexible to the individual needs of the reader. Some further research will be needed for me to embark on this project, especially with regards to component suppliers, as the author is American and list suppliers from the USA. Definitely a good read, but only half a build manual.
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2 of 2 people found the following review helpful:
2.0 out of 5 stars
More a prescription than a guide., 16 Feb 2009
Like some of the previous reviewers, I came to this book hoping to find out details about what CNC machines are, how they work, what they're good for and how to build a "get started" machine.
I think it's reasonable to expect that a book that tells you how to build something should also tell you why you should build it, what the trade offs are in the presented design features and also provide some introductory level detail in how it works. But (with one expection) that's not what this book does.
By and large, this book reads like a set of kit instructions to build a very specific device - but leaves you to source your own kit parts. I guess that'd be okay if you already knew about CNC in some detail and wanted to replicate the author's creation. However, there's precious little overview and almost no novice-level description of the finished thing and how(and for what) to use it.
Thus, in my opinion, the book is more of a prescription for a machine than a general introduction to the subject, set in the context of building a machine. I feel that the book therefore fails the majority of its potential audience.
There is one specific useful area for the newcomer. 53 pages of the 307 pages in the book are given over to a reproduction of a data sheet for an SCS-Thompson L297 motor controller chip. This actually contains a very detailed and accessible introduction to how multi-phase motor control works. This is an area I knew only a little bit about before, but the datasheet taught me so much more and gave me half a dozen "Aha" moments from things I'd not known or not fully understood before. But, you can download this datasheet for the L297 from the SCS-Thompson website for free anyway - now that you know it's there! This new knowledge was my main takeway from the book.
So, the book is (probably) great if you just want to slavishly reproduce the author's machine as a start point, but if (like me) your aims are more generalised or you just want to get an introduction to the subject so that you can roll your own machine, then I'm afraid I can't recommend this to you.
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1 of 1 people found the following review helpful:
2.0 out of 5 stars
great introduction but poor design, 24 Aug 2008
'Home-built' CNC is a fascinating topic with enormous potential. It sparked my interested and this was the only guide that I could find aimed at complete beginners. The background descriptions are simple to understand and the details of the build instructions and are very clear, however based on my own experience I would say the design and choice of materials is poor or out of date. For example the book proposes using welded steel box section, bolted aluminum sections from the likes of 'Rexroth' would be easier and perform better. Furthermore the book proposes using driving the lead screw from one side. that's crazy you should have two screw each side or one in the middle. I could go on. In summary, great introduction and workshop guide but bad design.
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