January 16, 2022
Last updated Jan 27, 2022
Machining is a process in which a material (often metal) is cut to a desired final shape and size by a controlled material-removal process. The processes that have this common theme are collectively called subtractive manufacturing - Wikipedia
Beginning in 2015, I had a couple of career moves that led me to learn about CNC machines and metal machining. I entered the field through woodworking, but quickly became interested in machining metal. I began learning on my own time, and eventually found a career opportunity where I could pursue that interest professionally. I’m not a full time machinist now, but it’s been a really useful skill to have.
I found the learning curve for machining to be steep. Compared to woodworking and computer programming, for example, there are fewer resources for someone looking to self-teach. Machining is a deep discipline, with lots of technical sophistication and specialized processes. The stakes of machining are also high- most metalworking equipment is expensive and dangerous to untrained users.
This article is a compilation of resources I have found useful when learning about machining. The primary focus is on the basics of metal machining, using manual and/or CNC machine tools such as mills and lathes. This encompasses the most common and useful processes in the machining world. My intent is that someone who is curious, but totally new to machining and metalworking can find helpful resources here.
A note about self-teaching machining #
Like any physical craft, machining cannot be completely learned at the desk or classroom. There is no replacement for hands-on experience in a safe, controlled environment. Although I consider myself mostly self-taught, I was fortunate to receive in-person guidance from more experienced people at certain times. I was also fortunate to have working environments where I could learn and practice on the job. The resources here will help you built and deepen your machining knowledge, but must be supplemented with safe hands-on practice, ideally under the guidance of an experienced person.
- Machining Fundamentals, 10th edition, by Walker and Dixon (2018).
- A great starting point, this is a modern textbook that could be used to teach a “Machining 101” course. Well-illustrated and approachable.
- Machine Shop Practice volumes 1 & 2, by Karl Moltrecht (1981).
- A hefty compilation of manual machining equipment and techniques. While it doesn’t cover modern CNC machines, it teaches fundamentals applicable to new and old machines alike.
- Sandvik Training Handbook
- Free PDF (select “Technical Information” on the filter at left, the Training Handbook download should be the first result). This is a well-illustrated textbook focusing on cutting tool selection and design for various machining operations. It’s a textbook version of the Sandvik e-learning course linked in the “Courses” section below. It uses Sandvik tooling for examples, but also teaches principles of cutting tool use that apply to all manufacturers.
- How to Run a Lathe, by South Bend Lathe Works (1914)
- Free PDF. This manual was included with early 20th Century South Bend Lathes. It’s a very useful introduction to the workings of a manual metal cutting lathe and basic lathe techniques. Don’t be put off by the antique style- while tooling has changed and improved, basic manual lathe techniques are still largely the same.
- Machinery’s Handbook
- This is an essential desk reference for any machinist. If you want to save money, pick up a slightly older edition. There are not many changes between editions and the older binding will likely be higher quality.
- ASM Metals Handbook (Desk Edition)
- Large, dense desk reference describing everything to do with the production, characteristics and use of various metal alloys. Please note that ASM also publishes an absolutely massive, multi-volume set of Metals Handbooks. I’m suggesting the desk edition, which is more concise. Like machinery’s handbook, I suggest finding an affordably priced used edition.
- Various quick/pocket reference books. There are many quick reference books out there. On my desk I have Engineer’s Black Book, the Machinist’s Practical Guide, various laminated charts and probably others I’ve forgotten about. Without exception, these are all compilations of information available elsewhere (mostly Machinery’s Handbook). They are edited and organized according to the author’s idea of what is most useful, which may or may not make sense to you. While lots of people like these little books, I’ve always preferred to make my own quick references, either by annotating/indexing existing resources such as books or webpages, or by using a note-taking program where I can organize text to my liking.
Special topics #
- Gears and Gear Cutting, by Ivan Law
- CNC Programming Handbook, by Peter Smid. Introduction to CNC programming. Keep in mind programming syntax and functionality varies by controller manufacturer and version.
- Foundations of Mechanical Accuracy by Wayne R. Moore. Describes the principles of precision manufacturing and machine design.
- Forces of Production: A Social History of Industrial Automation by David F. Noble. Historical account of the development of NC machines and their integration into factories.
Prefer a more structured, classroom style format?
- Sandvik e-learning
- Free online course. Not comprehensive, but a good supplement to other learning methods. Uses Sandvik products as examples but the general principles are widely applicable.
- MIT Machine Shop Course videos
- Free video course series covering common manual machines and techniques. A substantial 10 part series, with each installment lasting 30 minutes-1 hour. Unfortunately the video resolution is poor, but the instruction is straightforward and information dense. It is also available on YouTube.
- Titans of CNC
- Included based on recommendation of others. Free online courses, founded by machinist/reality TV personality Titan Gilroy.
- Mastercam University
- Included based on recommendation of others. Free courses for learning Mastercam CAD/CAM software, which is popular in the machining industry.
- Your local community college or trade school
- I don’t have personal experience with a classroom course on machining. Quality and availability will vary depending on location. Networking with recent graduates will help evaluate the quality of these programs.
- Apprenticeship programs
- I don’t have personal experience with a formal apprenticeship. In the US, quality and availability of these programs will vary widely depending on the location and employer. If considering such a position, I would critically examine whether others have gone through this program and their career outcomes.
- Iscar e-learning
- Similar to Sandvik, the tool manufacturer Iscar also has a set of online training courses. I have not tried it personally, but I have used some of Iscar’s other catalogs and resources.
YouTube Channels #
- Dan Gelbart’s series on building prototypes
- While this series isn’t primarily focused on machining, it’s a very informative walkthrough of a shop setup and techniques for quickly making durable prototypes using a variety of techniques. Great to see other skills that complement machining.
- NYC CNC
- Very popular channel covering many aspects of machining, CAD/CAM and running a machine shop
- Crash Course in Machining by Glacern Machine Tools
- Series of short videos about milling tools and operations. Decent overview if you are in a hurry, but not a substitute for more in depth study.
- Interesting project-driven channel with a focus on precision toolmaking
- Focus on manual machining techniques and vintage machinery
- Stuart de Haro
- No-nonsense howtos on a variety of machining topics
- Joe Pieczynski
- John Grimsmo
- Mazatrol Tips and Tricks
- Only relevant if you use a CNC lathe with a Mazatrol controller. If you do, this is an excellent resource!
- H&W Machine Repair and Rebuilding
- If you own or use a Bridgeport mill, this is a great resource for maintenance and repair videos.
Other online resources #
- Long Island Indicator
- LII sells and services precision measuring tools for machinists. They have a very large archive of articles on various measuring tools and topics. They also publish the “Companion Reference Guide for Test Indicators”
- Industrial supply house. They have an incredibly well-organized website and publish a large paper catalog. While this is a good place to buy supplies and hardware (although sometimes pricey), it’s also very illuminating to browse. Flipping through the paper catalog can show you lots of interesting and useful items that you never knew existed before.
- Tooling manufacturer websites. I suggest reading the free PDF catalogs and technical publications on each manufacturer’s website. They can be extremely informative, even if you have no intention of purchasing their product. Major manufacturers include:
Online communities #
- Practical Machinist forums
- This old-school forum is a wealth of knowledge and a great place to search when you have a specific question. It’s unabashedly focused on the world of professional machining and actively discourages posting about “hobby-grade” machines. This generally keeps the technical level of discussions fairly high. Many one-man-shops and small shop owners post here. Unfortunately, quality has declined in recent years due to decreased moderation. Can be hostile to newbies. So a great place to search, but not necessarily the best place to post unless you have specific, technical questions.
- CNCZone.com forums
- Huge forum, with dozens of sub-forums. Generally a lower level of technical discourse than PM, with a large proportion of newbies, hobbyists and infrequent or one-time posters. Lots of very specific subforums for different machine manufacturers/software, but this seems to dilute activity and most get low traffic. Still a useful place to search.
- As is typical for a subreddit, r/Machinists has many low content image posts but occasional good information. It is well trafficked by lots of people who will try to answer questions in good faith. The regular posts about wages/hours/shop culture are good for learning about typical working conditions in the industry, and relatively unfiltered compared to owner-dominated PM.
- Machinist Board
- Splintered off from PM, has similar content but lower traffic. Some subforums require a login to read.
- Home Shop Machinist forums
- I’ve never really browsed or posted on this forum, but it seems popular.
What these resources don’t cover #
As you learn more about machining, you will probably want to learn more about the following related fields:
- Learning CNC programming
- CAD and CAM software
- Principles of mechanical engineering and design
- Drawing schematics, geometric dimensioning and tolerances (GD&T)
Some resources mentioned here will touch on those topics, but you will likely need to seek out more in-depth resources depending on your requirements.
Readers may notice that most of these resources focus on professional and/or industrial machining processes and do not cater to a hobbyist audience. This is not out of snobbishness, but for a few simple reasons. One reason is that professional training materials tend to be much denser, theory-driven and rigorously edited. I prefer this style of writing when learning a new technical discipline. Secondly, hobbyist-focused learning materials and websites vary widely in quality. To speed up my own discovery and learning process, I have tried to read what the pros read and use the same references they do. Undoubtedly there are a lot of good, accurate hobbyist-focused resources out there, I just don’t have the time to sort the good from the bad. Finally, the principles of machining are the same whether you are a pro with a brand new 5 axis machining center or a hobbyist with a bench top mini-mill. The resources here are relevant for aspiring pros and hobbyists alike.
Suggestions and feedback? #
In this post I’ve mostly included resources that I’ve used personally. If you have a suggestion for something else to add, let me know!