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Sharing some project planning phase: A (digital) ELECTRO-MECHANICAL Network

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RJSV:
   Thanks for thoughts, contributing to the viability of some components, in even harsher conditions, as MOLY STEEL has potential. Hypothetical there, has sometimes been the 'SOLAR ATMOSPHERE PROBE", (sounds comical, but that sort of science involves 'skimming' close to SUN, briefly.)

   I'll have to think about your post, Coppercone2.  I guess a 'jig' has a pattern and a 'follower' pin, for guiding a nearby attached cutter. I want a Dremel tool with that...
  As to developers / fabricators cost:
   Latest progress on proto box involved 3 days, total about 16 hours, and so at nominal $20 per hour that's a labor cost (equivalent) maybe of $ 320. However, most formal employment, you maybe need to double that, covering (health insurance) the myriad of formal business expense.
  That's more closer to $ 600, and only a moderate gain in the prototype development.  (Any reader wants to send me that... I can spend even more than $ 600... maybe just for decent jig...)
   I estimated, 12 of those hours spent on serious machine shop tasks:  the rest of that time, 4 hours on just 'dinking' with things: That means staring and scribbling notes, and making tiny changes in the fit and friction, on that prototype model components.
(Also involves minor nasty 'ice pick' stab wound, to finger tip...)

   Now, (thanks again coppertone2), a MOLY-D version has to be adding substantial materials cost.

   Two mechanical issues, yet to be tested / addressed involve:
   1.).  The toggle lever movement needs to have a slip     
            clutch type effect, at the end of travel just to
            guarantee full travel, (but maybe not stall at t
             that completion).

   2.).   See photo diagram: pulleys need to be operated
             by either of two torques, with the other pulley   
             not adversely affected.  In simple view, turning
             one pulley will cause the other to turn, and this
             will also put torque 'backards' into the other
             driver pulley (3/4 inch dia. here).
             I need to observe, before tackling that, as
             my mechanical expertise is not 'expert'.

            By the way, eevblog hosts a great video,
     Dan Gelbert discusses prototypes, in machine shop.

coppercone2:
yeah your design has alot of unique challenges over a gear box, that was just my first idea of a starting point. I never even made a gear before, the best I  could do is resin print one. Interesting to read that though. Maybe I can make a brass one on my proxxon mill (I do have a kind of indexer), but it would require alot of learning. I know gears are very difficult to master.

And of course doing wax prints and casting gears is an option to make them metal cheap. I would think zinc cast would be easy, brass would be best. Zinc is stronger then aluminum and I think melts at a lower temp, if you get the right formulation, and it does not need you to engage in anything especially hazardous like molten brass (that is a big step for me). I think it might be possible to pour a very good zinc casting.. but its only conjecture

RJSV:
   Here is, a nice picture, (from inventor perspective),  showing the so-called 'BRIDGE' drive arrangement:

   The toggle lever is shown, left position in this view, where that is the 'selected' state.  The foreground input shaft has that little 3/4 inch mock-up pulley driver wheel, for that blue rubber band, the band going up, to the pivot axis. The bridge is intended for bringing the input rotation, ultimately, up, over, and back down to the 'tip wheel', that is the moving part for output.

RJSV:
...Now, this second picture shows, look for continuation of the input shaft, (thru the half-wall, look towards up, and left, for the OUTPUT shaft, continues that shaft direction).
   That's the output shaft, and it's almost as if the input could just be going straight through the switch box...
BUT what happens is the rotation is transferred up, over and back down, and for the non-selected case, will exit out the OUTPUT FACE as if continuous.
That's the 'data transparent' mode.
   Of course, my modeling abilities not so stellar; in this project I tried using heavy heavy paper (tablet backing) but it is so difficult to cut using Xacto knife, I'm going back to just saw cutting my boxwood, for 3D mock-up.
  As to why fuss over aligning the shafts, to some yet-nonexisting NETWORK rules, where input and output align, I figure why leave that major design feature out...heck, that's a ton of work to have to modify later.

RJSV:
...Those last couple posts help view one section, of the three section 3PDT switch, generally using 3/4 inch pulleys for driving the band. The arrangement first acts to bring the input rotation into alignment with the toggle arm PIVOT axis: that way the toggle arm can swing the 20 degrees or so, between stops, without causing tension changes, in that drive band.
   In the photos, the left is 'SELECT' and swung to the right is the un-selected or transparent switch position.

   That input shaft also must be located going 'through' the other main section, keeping clearance from any interference. That issue is why this 'working mock-up' is valuable, as a sort-of 3D design aid.
   Anyone have suggestions, PC software for modeling to find such interfere spots ?

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