Model Subjects that Inspire, and to Aspire to..

[Mark RandParticipant @markrand96270]

What can I say? I’ve got all of the drawings that survived from when it was built, but I don’t know if I’ll have the life expectancy to make it. 12 cylinders, 428rpm, 8,000hp. 965cc for a 1:10 model or 560 for a 1 inch to the foot model.

[Diogenes]

On Diogenes Said:

…
Nigel, yes, modelling ‘mechanisms’ is often overlooked, but as you say could probably be made an avenue of modelling to occupy a lifetime – I have seen cased ‘exhibition/demonstration’ models of ‘mechanisms’, I can definitely see the appeal of producing a couple of those, or even a series illustrating variations, or the ‘evolution of an idea’..

…

 

Here’s an example, developed by me from an outline plan in 1938 Detective Novel, mainly to exercise my Solid Edge CAD skills, but also to see how practical a mechanism it is.  (Not very!)

Can you guess what it is?

 

A doorknob, oddly elongated (partly my fault), with at least one strange external feature.  What’s inside?  The  wireframe view below shows why the Antikythera mechanism is so hard to understand, with lots of inconclusive hints and anything but obvious how it works or what it does.   Part of it is missing.

An exploded view helps:

 

Now we can see a spiral drive spring, an eccentric, two levers driven by the eccentric, and what might be a trip mechanism.  Here’s another view, confirming that grasping this doorknob releases a spring driven motor that spins an eccentric that waggles two arms to and fro. The trigger plate is underneath.

The purpose: it’s a fiendishly contrived murder weapon designed and built by a man with a workshop who needs to inherit big money quickly.  No harm in publishing this deadly device on the forum because the book is vague about an important detail, and it’s not in my version either. This missing parts would be difficult to make too!  Also, the death doorknob needs a very particular set of circumstances and a supply of rare snake venom with a dead snake.  The perpetrator needs the door-knob to fake an accidental snake bite because the victim works with snake venom.

The book is “Antidote to Venom” by Freeman Wills Crofts, who was a pukka Railway Engineer.  Once known as “The King of Crime Writers” when Agatha Christie was Queen, he’s moderately forgotten now.   His books are of the puzzle solving type, with alibis broken by measuring speeds and distances, checking railway timetables and other technically sound methods.  Not famous now I think because the novels wouldn’t be easy to televise.  There’s not enough action, and a good deal of routine police work that slowly homes in on the criminals.   A good read if you like puzzles, sadly not photogenic compared with the likes of Poirot, Miss Marple and Lord Peter Wimsey.

The doorknob of doom put me and Solid Edge to the test, and I’ll share some of the misadventures in the CAD section later.  Turns out Solid Edge has some odd shortcomings, and so do I…

Dave

 

 

 

[JasonBModerator @jasonb]

The image of the Canon came from this forum

Nick It is tempting to replicate the old distressed finish which I have done before but will probably not do it on this engine. Still trying to decide if it was painted green and brown or if there is more rust than I think

[Nicholas FarrParticipant @nicholasfarr14254]

Hi JasonB, not got a problem with you painting it, and I expected that you would. My thinking is, it’s proud to look the way it does, as it probably paid its kept over and over a few times. It is tempting to look a green colour originally though.

Regards Nick.

[Author]

Posts