Sunday, March 20, 2022

A Poor-Man's Skyhook

  A few years ago, I suffered some serious muscle strains in my lower back and glutes, which gave me a temporary bout of sciatica and scared the crap out of me.

 The injury happened when I lifted - single-handedly, the twelve-inch Bridgeport rotary table off of my mill table.  It weighs 130 pounds.  Oooops.

 When I recovered enough that I could sit up in a chair in front of my computer again - or stand up, or walk - I started shopping for material handling solutions for this kind of lifting that I could apply in my small, cramped shop.

 The first thing I found was the SkyHook, and to be sure it is a thing of beauty and a joy forever.

 It also costs thousands of dollars, and thats just for the little yellow crane, before you even get into additional accessories like the cart, or attachments to mount the crane post to the tool post of a lathe, or to the t-slots of a mill table...

 Don't get me wrong, I've seen these in action in videos, it is clearly a nice tool if you can afford it, and when this topic came up between me and a good friend of mine who has money, I suggested he buy one.

 But my budget is more beer than champagne, so decided to build one.

 What I will end up with will not be as easy to use, or as smooth in adjusting of the height.  Mine won't have the chain feature (instead of cable) which prevents the load from twisting - a nice feature.  Mine will automatically brake the load, because I am using a cheap electric hoist instead of a fancy gearbox, friction clutch, and handwheel.

 Mine will also cost less than $200 all up, because I already had the cart, the high-weight-capacity expensive casters I needed just - showed up - in the alley one day (I kid you not) the hoist was about $100, and the additional steel bits I need are much less than $100.  In fact, I have all of the steel and parts except the vertical piece of pipe, plus whatever I come up with to go over the pipe and swivel on it (with a thrust bearing).

 The rig will look something like this:

 The jib extends 24" from center, or 12" past the edge of the 24" wide cart.  With some weight in the bottom, I shouldn't need to extend the casters on the hoist end on out-riggers, to lift any tool (or likely work) I can think of - I am unlikely to work on anything that approaches the weight limit of the hoist.

 Some time next week I will run out to my favorite scrap metal yard and buy the vertical bit.  A standard corner post for chainlink fence would be the right material, except that it's heavily galvanized and I need to weld on this, so I need tubing or black pipe.  The good news is that plain carbon steel is cheap, because right now, so am I.

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