KMODDL: A Mechanism Maker’s Dream Site.

Computers are relatively new still, but we’ve had mechanics for a very long time. KMODDL  keeps us from reinventing the wheel. It contains collections of mechanisms with descriptions, pictures, and even videos. We were working on a arbalest design not too long ago, and we were having trouble coming up with a clever ratchet design for one of the parts. We spent a few moments in KMODDL looking through the ratchet section of the Reuleaux collection, and  soon after we had the basic building blocks of our design. Sure there are books you could buy that do a similar thing, but KMODDL is completely free, very in depth, and easier to search. Plus, with a useful tool like this you might not even have to take apart all your appliances anymore to see how they work. My first sewing machine might have lived a longer life had I seen this first. Anyone know of more resources like this?

20 thoughts on “KMODDL: A Mechanism Maker’s Dream Site.

  1. A number of years ago a group of us got in on a deal to buy a few copies of “Illustrated Sourcebook of Mechanical Components”. It’s not a cheap book but it is a massive tome filled with lots of little odds and ends (not just gears, linkages, etc but also how to join sheet material together and use of dished washers). It contains quite a few pivot tables to allow you to actually calculate values required on some devices.
    I’d recommend a read of it should anyone have a chance, if only to give you a few ideas at the least!

  2. Machinery’s Handbook is still expensive – $75 used on amazon. I wish I had a copy! Really, I NEED a copy.

    The latest edition is 2700 pages.

    Does anyone else find referencing or reading large books like that difficult on a reader or computer? Especially in a shop. I much prefer the ability to flip and skip around. Though searching on a computer is sometimes nice.

    When reading those old books, it is readily apparent just how much smarts and know how we are rapidly losing.

    Those wise and experienced old mentors we consult on our projects – if we are lucky to have any – aren’t going to be around forever.

    1. Just about every Gerstner or Kennedy toolmaker’s toolbox had a drawer specifically for the Handbook. (it’s that tallish middle drawer) The newer models of Gerstner have a different layout now that they are catering to hobbyists instead of professionals.
      ($980 for a toolbox??? I have a model 52 Journeyman box. You DON’T want to know how much I estimate the tools I made cost as well as the ones I purchased)

      I find the older editions of Machinery’s Handbook more interesting, there’s things like recipes for various lubricants and proper flooring for foundries, blacksmiths shops, die and mold maker shops (thick parquet wooden floors to protect the steel should it be dropped after many hours of work, concrete is no good) It’s interesting the information that has been dropped over the years from subsequent editions. A 1920’s editon had different info from a 1944 edition, from a 2012 edition.
      The well thumbed pages in my 28th edition book were the sections on gears and screws and screwthreads. I designed a lot of tooling to make gears over the years, got to keep that addendum & dedendum clear in my head.

    2. The information is around, it’s just separated by the digital divide.

      There are tens of thousands of old guys around that know everything – but they’re generally anti-social, having been the geeks of their generation. Extracting information from them can be very difficult compared to using google, and many are unable to work in anything other than stream of consciousness mode.

      The Lindsey pubs are pretty good, but circa WW1 to 1960’s/1970s science and mechanics magazines are pure gold. More recent information exists – and is sometimes available on CD or DVD – home shop machinist, all that stuff.

      The best place to ask mechanical questions is on the various CNC and machine shop forums. The ones that have jumped the divide often hang out there.

      Google is amassing huge libraries of this stuff, but it’s not being done for the good of mankind – there is no replacement for having your own copies.

      There are a few russian, chinese and indian websites with scanned copies of rather interesting and valuable out of print books covering all things technical.

      These are getting very hard to locate, and are often actively “jammed” through connection resets.

      The Lindsey stuff is an excellent hard copy repository of older (“pirated”) technical works, grabbed under previous copyright regimes that made it legal at the time.

      I have found some excellent sets of aviation journals dating from around 1901 to World War Two, repackaged (“pirated”) by Tab books, and showing all phases of aircraft construction and testing from a point when the aircraft industry was full of beginners. Very Edifying.

      Some may object to my use of the term “pirated”, as all of these appropriations were once permitted by law… but I assure you that this word is being re-purposed and extended just like the word “hacker” was.

      Please – if you have old valuable publications, I urge you to consider scanning them at 150dpi or more and then, you know: Keep them safe for future generations.

      When you die, your kids will simply send your stanky old books to be incinerated. Think about the next generation of doers… they might be dumb as rocks, but at least they’re curious.

      If a couple of those kids archive a little extra information, you’re extending the flame.
      Do it!

    3. $75 for anything hurts for most in the 1% and those between 1% and 99%, however $75 for 2700 pages of good information can be seen as a good bargain as well. This is where hackerspace libraries come in. obtain books as these, and never let them leave the library, when one can take a photo of the info they need home. In the event anyone is tempted to bust me on it, no I was not implying that those who now own the book or purchase now are members of the 99% or ever where.

  3. I have a book from the early 1900s that was my great grandfathers that I use called “Inginous mechanisms for the inventor” thats been one of my favorites since i was a kid. He was a machinist now I am a hobby machinist and its worth its weight in gold.

    1. That’s OK contrary to what many hackaday commentators seem to believe benign grammar and spelling mistake can’t aren’t really injurious to one’s physical well being, when compared to build mistakes. Yes I know that grammar and spelling mistakes that impart erroneous information aren’t benign, but some of the mistakes pointed out are often petty. :)

  4. We can make lights blink, store information, do calculations, control motors and electromechanical devices. But to truly interact with the world at some point you need to get into the gears.
    What an awesome site!!! Thank you for sharing.

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