dog with book


Anytime I have to do the same calculation twice I start thinking about how to automate the process. The result is this collection of excel calculators & cheat sheets. You are invited to download these documents and use them as you wish, everything here is free and always will be!  -Enjoy!

relative properties of beam sections

Wire Sizing Guide


speacilty tool ruleThe multi-tool Rulecommon-robot-configurations

 Bolt Sizing Calculator (EXCEL) Calculate the strength of any size fastener.
 Heat Sink Quick Reference (PDF) Quickly design a custom heatsink.
 Strength of Materials Calculator (EXCEL) Calculate the strength of simple beams.
 Clevis Sizing Calculator (EXCEL) Calculate clevis strength and hole tearout forces.
 Wire Gauge Sizing Calculator (EXCEL) Calculate the ampacity of electrical wire.
 Shaft Key Sizing (EXCEL) Calculate the torque rating of shafts and keys.
 Air Cylinder Force Calcs (EXCEL) Calculate the force from pressure cylinders.
Ball Screw Calculator (EXCEL)  Determine the buckling load and critical speed of ball screws and lead screws.
Electric Motorcycle Calculator (EXCEL)  Estimate the performance of an electric motorcycle design prior to building one.
Engineering Economics Calculator (EXCEL)  Engineering economics class in an nutshell
Investment Portfolio Performance Tester (EXCEL)  Intended as a pseudo-realistic illustration of how an investment portfolio might perform over time.
 Financial Survival Pocket Guide (PDF)  Provides a succinct yet solid baseline for money management and investing skills.
 Simple BOM for Hobby Grade Use  (EXCEL)  Provides a starting point for a DIY grade bill of materials. Example provided is the TestrBot project.
3D Printed Part Cost Calculator (EXCEL) Calculate the cost per assembly of kits containing 3d printed and non-printed components


*This list is a perpetual work in progress. Check back every once in a while to see whats new! (I also take requests)

**The calculator excel documents are protected for quality purposes, use the TAB button to cycle through the unlocked cells.

***I cannot claim responsibility for any unintended consequences caused by the use or misuse of these resources.


***GREAT OFFSITE READS*** ***DESCRIPTION:*** R&D Hardware Guide. Excellent read on strategic prototyping methods, lessons learned from development experience, and expert insights. 5 Programming  “Rules  of Thumb” G.L. Huyett Engineering Handbook: Awesome free eBook on steels, steelmaking, mechanical properties, metalworking, heattreatment, manufacturing, and metal part finishing. (Sorry had the wrong link!) Guerrilla guide to CNC machining, mold making, and resin casting. (CH6 is excellent even if your already good at cnc machining)


Engineering (& Related) Books
***Link For The Bookshelf*** ***Title*** ***DESCRIPTION:*** Machinery’s Handbook Classic reference book. This is the most popular reference book for metalworking, design, engineering, and manufacturing shops that I can think of. Shigley’s Mechanical Engineering Design Review Pending Ultimate GD&T Pocket Guide: Based on ASME Y14.5-2009 Review Pending Marks’ Standard Handbook for Mechanical Engineers Review Pending The Art of Electronics Classic Electrical Engineering Book. Covers many areas of circuit design, from basic DC voltage, current, and resistance, to active filters and oscillators, to digital electronics, including microprocessors and digital bus interfacing. Machine Shop Trade Secrets Intended for machinists needing good basic knowledge of machine set up as well as the experienced folks wanting to learn some good shortcuts. It isn’t dry and full of feeds and charts, just good basic info and excellent tips and tricks. Machining for Hobbyists: Getting Started Clear and concise guide with great illistrations Mechanical Engineering Reference Manual for the PE Exam  This book is a great test preparation tool and a great general reference to have anyway. Its full of specific equations and succinct theoretical explanations.
I have yet to take the PE exam, but when I took the FE exam I remember crushing it because I had studied the reference material itself. I didnt do any practice problems, just brush up on what equations are used when and reminded myself of some obscure material. You are allowed to use the book during the exam, so familiarizing yourself with it before hand is essential. Cooking for Geeks: Real Science, Great Hacks, and Good Food by Jeff Potter Although there is some organization to the book, like most cook books, it can be opened to any page, and there is likely to be something interesting to peruse. It is not put together as a textbook on cooking. If you enjoy experimenting, using the scientific method in your cooking, if your curiosity isn’t satisfied by just following a recipe time after time, you’ll enjoy this book.
It answer questions that most cook books don’t think about asking. And if you have any curiosity about why recipes turn out like they do, and are interested in experimenting, using a knowledge of chemistry and physics to improve your dishes, this is a great book. 101 Things I Learned in Engineering School Each chapter is a two-page spread with an illustration on one page and one-to-three paragraphs of text on the other. focuses on a given engineering concept. Some of the chapters feature appropriate quotes.
With great illustrations and brief descriptions, this book is a great intro to many useful ideas. Good bathroom book. 101 Things I Learned in Architecture School by Matthew Frederick Each chapter (a two-page spread with an illustration on the left page and one-to-three paragraphs of text on the right page) focuses on a given concept that is important in architecture. Some of the chapters feature appropriate quotes.
With great illustrations and brief descriptions, this book is a great intro to many useful ideas. Good bathroom book. Unwritten Laws of Engineering: Revised and Updated Edition by W.J. King A quick read, this is a good one for anyone starting out as an engineer in any field. The book focuses on the soft skills aspect of the engineering what usually good engineers lack. Though its old, the ideas are about dealing people, so they are timeless. Universal Principles of Design This fully illustrated book introduces various design principles that truly are universal. It explains 150 concepts of design pertaining to disciplines including architecture, software design, security, marketing, and productivity. Every entry is concise, but includes at least one specific example. There is little to no room for misunderstanding.
This is more of a dictionary than an encyclopedia. It is not being marketed as a manual and should not be mistaken for one. Good short read / bathroom book. Audel Millwrights and Mechanics Guide Review Pending Schaum’s Outline of Machine Design Review Pending. Right to the point useful reference. Learning tool.


Business Books
***Link For The Bookshelf*** ***Title*** ***DESCRIPTION:*** The E-Myth Revisited: Why Most Small Businesses Don’t Work and What to Do About It My single favorite business book. How to Develop Self-Confidence And Influence People by Dale Carnegie How do you tell the difference between an introverted and extroverted engineer? An introverted engineer looks at his feet when he talks to you and an extroverted one looks at *your feet*.
Engineers are known for being smart folks, but not so much for their ability to communicate. This book is an excellent guide aid for those of us needing to develop on that weakness. The Startup Owner’s Manual: The Step-By-Step Guide for Building a Great Company Review Pending How to Fail at Almost Everything and Still Win Big: Kind of the Story of My Life by Scott Adams Written by the creator of Dilbert comics, this book is more aptly described as ‘How to Think towards/about Success’. It is a book of opinions though ones that make good sense. The basic premise is that success is not easy… but it’s achievable for anyone. Bringing a Hardware
Product to Market
Review Pending The incredible secret money machine Free! See review from article The Four Steps to the Epiphany Review Pending Zero to Maker: Learn (Just Enough) to Make (Just About) Anything Review Pending Made to Stick: Why Some Ideas Survive and Others Die by Chip Heath This book is about how to make your ideas memorable! Weather its promoting a product or project, being a professional, forwarding a company’s strategy or lessons to students. Everything revolves around the SUCCESS methodology.For an idea to stick, for it to be useful and lasting, it’s got to make the audience:
Pay attention – Unexpected
Understand and remember it – Concrete
Agree/Believe – Credible
Care – Emotional
Be able to act on it – Story. Influence: The Psychology of Persuasion by Robert B. Cialdini Included here because this is a fascinating read for us folks who naturally understand machines but not so much on dealing with other people.
This book is a tool that will enable you to take your ideas farther and avoid being taken advantage of.


Personal Finance Books
***For The Bookshelf*** ***Title*** ***DESCRIPTION:*** A Random Walk Down Wall Street: The Time-Tested Strategy for Successful Investing by Burton G. Malkiel  Show me an engineer uninterested in personal finance and I’ll show you an authentic photo of bigfoot. Seriously, proper money management skills has an outsize effect on your life and yet it is poorly covered in traditional education.
Not that there is a lack of info on this topic…there is an immense amount out there but the noise to signal ratio is too damn high!
If I had to recommend one signal book on the topic of managing your life savings, it would be this one! Early Retirement Extreme: A Philosophical and Practical Guide to Financial Independence Review Pending


  1. Great, except units of recommended tightening & ultimate breaking torque in the Bolt sizing calculator should be lb-in not in-lb.

    You have it expressed as an energy (scalar) where it should be expressed as torque (vector)


  2. Kudos for your willingness to share. I was looking for max loading for reciprocating lead screws which have rather wide customized applications, when I came upon your site. Guess I will have to make trials and errors to see their (Reciprocating Screws) “breaking” point, myself.

    Liked by 1 person

  3. Could you make new entries under the materials cell for 301 spring tempered steel as well other “springy” alloys such as 1075, 1095, etc.?


  4. I really like the look of your clevis calculator but it I need a few more features to be really useful. SI Units, ability to specify other materials and radius clevis ends as well as square ends. Might you consider adding these?


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