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A while ago MAKE did a post on A Beginning Engineer’s Checklist from the PIClist site.  And while I love these kind of lists, it left me – as a mechanical engineering – feeling a little left out, with all the talk of chips and Ohm’s Law and power busses (oh my!).  It also reminded me of a list we had posted on a bulletin board at my first job, called Akin’s Laws of Spacecraft Design, which definitely apply to more than just spacecraft.  So here’s my attempt at rearranging and adding to these lists to give them more of a mechanical flavor and include some of my own lessons learned over the last few years.

1.  NEVER loan out your copies of:
Machinery’s Handbook
Shigley’s Mechanical Engineering Design
Making Things Move: DIY Mechanisms for Inventors, Hobbyists, and Artists (okay this one is a shameless plug, but Dug North told me it’s “destined to be be a classic of sorts” so you can blame him)

2.  Project planning follows the rule of pi.  Take how much time you think you can complete something in, multiply it by pi, and that will be the actual length of time it takes.

3.  Parkinson’s Law: Work expands so as to fill the time available for its completion.  Don’t give yourself too much time for a project or it will never get done.  Speaking of done, check out The Cult of Done Manifesto.  If it weren’t for the last minute, nothing would ever get done.

4. Everything is a spring.

5. If it moves and it shouldn’t, use duct tape.  If it doesn’t move and it should, use WD-40.

6. Document everything you do.  Someone will ask you to justify your design at some point, and “it kind of sort of looked right” is never a good answer.  This is especially true on collaborative projects.  The group will forget who did what and it will make going back and changing things that much harder.

7. Design is an iterative process. The necessary number of iterations is one more than the number you have currently done. This is true at any point in time.

8. Ask questions.  If you don’t know something, say so.  Your credibility as an engineer lies not in being infinitely intelligent, but in knowing how to get at the right resources to figure it out.  If you cheat, people will die.

9. Designing for disassemble is just as important as design for assembly.  It will never work the first time you put it together.  Oh, and make sure that everywhere there is a screw, there is a place for a screwdriver to install it.  And for a hand to fit around said screwdriver.

10. Business will always be a part of engineering.  Don’t work for free (unless you really want to) and don’t work without a contract.  Don’t design a better mousetrap THEN expect someone to want it.  The products that sell the best are not necessarily the ones that are technologically superior.

11. Design is based on requirements. There’s no justification for designing something one bit “better” than the requirements dictate.  Better is the enemy of good enough.  Get it done then go play outside.

12. Engineering is done with numbers. Analysis without numbers is only an opinion.

13. Be friendly and talk to your machinist and/or shop techs.  You may have a fancier title or degree, but that does not make you better.  A short conversation on how to make a part more easily machinable/moldable/etc. can save thousands of dollars and make you both look good.  You may even learn something.

What would you add to this list? Tell us in the comments.

More:
The Beginning Engineer’s Checklist


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Comments

  1. Alfredo Jara says:

    As a mechanical Engineer myself, I totally agree with this content. Along with the bachelor diploma, a copy of this should be given to evey mechanical engineer! Most of the stuff on the list I had to learn myself.

  2. Anonymous says:

    Rounding out the old time triumvirate of electrical/mechanical/chemical: “The” chemical engineering book is “Perry’s Chemical Engineer’s Handbook”. Another reference work that should be useful to anyone making things from scratch is the “CRC Handbook of Chemistry and Physics”. It covers a mind-blowing number of processes for converting raw materials into useful stuff.

    The chemical engineering equivalent for rule #4 is: Everything is a bomb. Know exactly how much pressure your vessels can hold.

  3. johngineer says:

    I would expand on #13 to say that it is well worth your time and effort to learn machining and manufacturing yourself, at least at a cursory level, even if this is not your specialty. All electrical engineers should know how to solder, and all mechanical engineers should at least know how to face a part on a lathe, and tap a thread. Good engineers should at least be aware of g-code — how it works and what you can (and cannot) do with it.

    And #14 — Nearly every problem is caused by heat. Heat is the enemy.

  4. Mark Wilson says:

    #13 is the most important one on the list. I learned more from the machinists who learned their craft on tenders in the south pacific in WWII then I ever learned from a book. and once you have a design, take it out to the shop floor and work with the guys who need to make it, how to improve the design so it’s easier (and cheaper) to make

    1. I agree – I learned this by being told at one of my first internships in college, and then learned this through experience at my first job. I think that having the same level of respect for the cleaning crew and the president of the company keeps your mind friendly and open – you never know who you can learn from.

  5. tonyvr says:

    KISS — “Keep it simple” + your favorite expletive that begins with ‘s’.

  6. Roger Haley says:

    #13 should be closer to the top. Maybe first.

    1. A very important point indeed. I certainly did not order in terms of priority – I agree this is an important one!

  7. ian says:

    i also love #13.

    in particular the line “You may have a fancier title or degree, but that does not make you better.”

    It drives me nuts when other Engineers have the attitude that they are smarter, better, and know it all because they got a piece of paper.

    Having the humility to treat machinists and techs as equal humans who can teach you more about design that any stupid class is the most important thing i learned while getting my BSME.

    1. Rich Barker says:

      I hate this attitude! I am going to school with a lot of engineers-in-training with this mindset.

      Look, I understand that some people are more adept with physical problem solving, but just because a student is training as an engineer doesn’t give them a free pass to be an elitist jerk. Everyone has to start somewhere, maybe instead of treating “laymen” like idiots they could spend time educating them! My favorite part about being an engineer is explaining to others how things work!

      1. If you can explain a concept to someone else in non-jargon words, it usually helps you to fully understand the concept as well. Also, you give the person you are explaining it to a more complete understanding of the problem/issue/ condition (Not ‘smarter’, just more aware).

        I had a lot of fun over the years explaining that just because something is ‘harder’ doesn’t mean it will flex less under load. (Young’s modulus) This still gets good results from machinists when someone is trying to make something not bend. Also ‘stainless steel’ is not inherently ‘better’ than carbon steel. (This comes up all the time)

      2. Stuart R says:

        “My favorite part about being an engineer is explaining to others how things work!”
        Ask them, I’ll guarantee that’s their least favorite part of knowing an Engineer.

      3. Stuart R says:

        “My favorite part about being an engineer is explaining to others how things work!”
        Ask them, I’ll guarantee that’s their least favorite part of knowing an Engineer.

  8. I’m not an engineer, so #4 is lost on me. What does “Everything is a spring” mean?

    1. Anonymous says:

      Everything acts like a spring to some degree. All of the parts in an assembly will deform slightly under load. If you don’t take this into account very bad things can happen.

  9. Emyr Derfel says:

    #5

    As a cyclist, sound technician and programmer/geek/network engineer, I contest that Zipties are more useful than duct tape. Yes, as a sound tech I used both zipties and duct tape, but zipties are far less messy and have more get-you-home uses.

    1. Homer68 says:

      Zipties do have their uses but they do tend to weaken and snap when exposed to certain chemicals as well as excessive exposure to UV light.

  10. Combining #8 and #11: Find out what your customer really wants. Often on big jobs, you’ll get mounds and mounds of specifications, codes, etc. These are often put together by people who do not fully understand the job. Ask why a particular technology was selected or spec’d if it doesn’t make sense to you. You may find out that “that’s how the last one was done…oh, and we’ve had problems with it.” You may figure out the solution that puts you in front.

    The opposite of this is that if the process is run in such a way that all potential vendors’ questions (and the answers) are shared with everyone else (real big nowadays with “spend management” and ERM systems), keep your mouth shut. Don’t give your ideas or advantages away to your competition. Work around the system, if possible, to find the people in the know who can answer your questions without getting them spread around.

  11. Also, Eshbach’s Handbook is a good general handbook to have around.

    ChemEs should also get McCabe, Smith, and Harriot’s unit ops book if they don’t already have it. Lots of good info. If you’re a mechanical engineer working in the process industry, this and Perry’s will be a big help to you.

  12. Dave Akin says:

    Maybe you could link to the original?
    http://spacecraft.ssl.umd.edu/akins_laws.html
    – Dave Akin

  13. My Dad, a controls engineer for McDonnell Douglas gave me “The Unwritten laws of Engineering” by W. J. King when I graduated from school 20 years ago. It was written in 1944 and I have to agree that everything in it is applicable today (except for the blatant male bias).
    Here is the link: http://www.engineeringrecords.com/Private_Companies/Unwritten%20Laws%20of%20Engineering.pdf

  14. Ho Liu says:

    Although I agree with no.6, I have to disagree with “it kind of sort of looked right” is a bad answer. Most of my designs start somewhere and it usually starts by ‘looking’ right.

  15. jon shupe says:

    Far too complex. There are only three things than any engineer should know:

    1. F=MA
    2. E=IR
    3. Don’t push on a rope.

    Everything else can be derived.

  16. Anonymous says:

    Mechanical Engineering Internships encompasses several engineering disciplines and was developed as a result of applying principles of physics and materials science. Mechanical engineering is based on generation and application of heat and mechanical power and the design, production, and use of machines and tools.

  17. T says:

    As an engineer in training, I promise to always respect my techs. The can do things I could never do.

  18. Mike Lever says:

    I would add,
    Allow for metal finishing. Design it without blind holes, fluid traps and perhaps somewhere to attach a wire and the plater will like you. Give him a week to do it instead of a day and we will love you and probably do it quicker!
    And if you talk to the plater they maybe will suggest the best finish. Chrome is not always best. Triple plating is unnecessary.

  19. You missed the number one mistake every young engineer will make, inconsistent tolerances. If you do perform your geometric tolerancing correctly, the best machinist in the world will still make you a part which doesn’t fit. Stacking tolerances are the number one cause of new engineers design failure.

  20. Mike Cook says:

    love it, my grandfather and father are both machinists and i worked for them until i was 26, then i decided to go to school, and after reading this and esp 13, i know that i will be able to better design whatever my life my throw at me. this is great.

  21. As a mechanical engineer still in school we are constantly told to respect all those around you. The person cleaning the building is just as important as the person in the CEO seat. We also are made to do machining in more than one ME course. I think that was my favorite day ever as a ME. We got to use our hands. 

    1. Stuart R says:

      Your favorite DAY as an ME. hmmm but it was in more than one ME class??? 

  22. Keith Irwin says:

    I HOPE business is not always a part of engineering.  Engineering will take over economics when we replace all labor jobs with technology.

  23. Ivan says:

    LIKE THIS!!! :)
    can I post this on my blog? 

  24. Malcolm G says:

    If you have a budget, plan on it as if it was less.
    So when Murphys’ Law comes about, and it will, you can compensate.

  25. 5. Replace WD-40 with Aero-Kroil and and duct tape with sika-flex.

    9. This is probably the most important number on the list aside from #13. I work on a shipyard and I can’t tell you how many times I’ve had to spend 30 minutes to remove one galled-up, rusted bolt because someone didn’t leave enough room for a ratchet head or a decent amount of wrench swing. I’ve probably ruined more tools than I care to admit compensating for engineering oversight. Remember: Your fasteners will rust and some disgruntled peon is going to have to remove them. At least leave him enough room to torque them off in the name of human decency.

  26. 5. Replace WD-40 with Aero-Kroil and and duct tape with sika-flex.

    9. This is probably the most important number on the list aside from #13. I work on a shipyard and I can’t tell you how many times I’ve had to spend 30 minutes to remove one galled-up, rusted bolt because someone didn’t leave enough room for a ratchet head or a decent amount of wrench swing. I’ve probably ruined more tools than I care to admit compensating for engineering oversight. Remember: Your fasteners will rust and some disgruntled peon is going to have to remove them. At least leave him enough room to torque them off in the name of human decency.

  27. John Spain says:

    Here’s another important concept as well.  Dont question a man about how
    he feeds his family.  You may be a PE, but that doesnt mean you know
    more about sheet metal than the guy thats been feeding his family as a
    sheet metal worker for the past 30 years.  #14. Know your limits,
    recognize your faults.  (Im an ME major so bear with me).  Ive seen
    smart guys design great things only to find out that theyre too big to
    fit through the door of the shop. The PE on the hill probably wont know that, but the guy bending your metal in the yard will.

  28. John Spain says:

    Here’s another important concept as well.  Dont question a man about how
    he feeds his family.  You may be a PE, but that doesnt mean you know
    more about sheet metal than the guy thats been feeding his family as a
    sheet metal worker for the past 30 years.  #14. Know your limits,
    recognize your faults.  (Im an ME major so bear with me).  Ive seen
    smart guys design great things only to find out that theyre too big to
    fit through the door of the shop. The PE on the hill probably wont know that, but the guy bending your metal in the yard will.

  29. John Spain says:

    Here’s another important concept as well.  Dont question a man about how
    he feeds his family.  You may be a PE, but that doesnt mean you know
    more about sheet metal than the guy thats been feeding his family as a
    sheet metal worker for the past 30 years.  #14. Know your limits,
    recognize your faults.  (Im an ME major so bear with me).  Ive seen
    smart guys design great things only to find out that theyre too big to
    fit through the door of the shop. The PE on the hill probably wont know that, but the guy bending your metal in the yard will.

  30. Ryan Cahoon says:

    #2

    Personally, I prefer Hofstadter’s Law: It always takes longer than you expect, even when you take into account Hofstadter’s Law.

  31. Craig Libuse says:

    Another book that every beginning engineer should read is “Tabletop Machining” by Joe Martin. It’s subtitle is: “A basic approach to making small parts on miniature machine tools…what every engineer should know about machining, machinists and manufacturing.” Although it uses small parts and small machine tools in the examples, the principles are universal and highlight the problems of engineering from the perspective of the machinist who has to make the parts the engineers come up with. A few simple tips can help you make parts that actually work and don’t cost a needless fortune to make. Besides that, it’s a fun read with lots of color photos of cool things people have made using benchtop tools.

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