Friday, March 17, 2023

a material handling incident Wile E. Coyote would have recognized

  So there I was*, minding my own business in my shop, making a lifting rig for my rotary table, so I can hoist it to and from my mill's table with ease and safety...

 For a while now, said rotary table has been sitting on a wheeled cart, on top of a random steel framedingus to bring it to a convenient height, all just so I can move the damned thing around the shop easily.  note: the top of the cart has carpet on it.  (former bell cart)

 The steel framus is just a random leftover, roughly cubic, from something I once took apart.
note that it is smooth(ish) and painted on top.
note that the bottom of the rotary is very smooth indeed... and it leaks oil.
  (ooh! foreshadowing!)

 Said cart was in my way, so I gave it a shove with one foot.  A hard shove, since there's some two hundred pounds total mass there.  To my astonishment and horror, the cart moved smartly as intended, the cubical framatron went with it as intended, and the rotary stayed put in mid-air for a split instant (because Newton was a savage motherfucker, shit must have been wild before he invented inertia) then succumbed to gravity and fell to the remaining top of the cart.

 It did not hit the cement floor and break (cuz cast iron, cuz!) and it did not touch my foot.  My ancestors were looking out for me this morning.

 I moved the cart to take the picture, but everything on it remained where it was after the incident (and will remain there - the rotary at least - until the paint has dried on the second half of the lifting sling I was making).  The gizmoframe was shifted by the table coming down at an angle.  No toes were harmed in the making of this safety film.


 Speaking of lifting slings; the reason I was making a lifting sling is that I have (temporarily, until the hoist cart is built) rigged a hoist over one end of the mill table, enabling me to get the 59kg / 130lb beast up and down without hurting my back.  So far so good.  But the table has long rods for handles, 11.5cm / 4.5in long.  Putting a chain sling or hooks on these and lifting is dangerously unstable.

 Maybe I've spent too much time as a Texas Tank Watcher, but the "correct" solution seemed obvious: make a custom lifting rig which solidly prevents shifting and makes for a clean, level lift.  This we then do.  I finished the first half a few days ago.  Fabbing the second hook took only a few hours early this morning, followed by primer.  I will update this post showing it in use when the paint is dry.

 This is a typical pattern of fabrication for me whenever I need to make more than one of something (unless I have drawings and am doing precision or interchangeable parts); I complete one to figure out how to do it, then I make numbers 2 through N, subtracting any mistakes I made on the first one.

EDIT: action shot:

 


 

 

 

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* 'there I was' indicates this is a 'war story'.
If this were it a fairy tale, it would begin with "once upon a time."


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