On Sat, 31 Jul 2004, Werehatrack wrote:
|On Fri, 30 Jul 2004 20:11:44 -0700, Matthew Montchalin
|<[email hidden]> wrote:
|
|>On Sat, 31 Jul 2004, RonSonic wrote:
|>|On Fri, 30 Jul 2004 09:43:57 -0700, Matthew Montchalin <[email hidden]>
|>|wrote:
|>|>I'm trying to build a bicycle-powered 'forklift' if that helps anybody
|>|>understand my objective here. The platform is supposed to rise up from
|>|>the jacking action of a cogwheel cranking the straight-edge up from
|>|>under.
|>|>
|>|>I only want the 'forklift' to go up 3 or 4 feet or so, and no higher.
|>|
|>|So you want to make a rack gear and use a cog to drive it. Bad idea.
|>
|>You sure?
|>
|>|The teeth on a chainwheel are designed to mesh with a chain, not a gear.
|>|They will NOT reliably support any amount of weight like this - at least
|>|not enough weight to make all the monkey-motion desireable.
|>
|>The load to be lifted is about 15 to 25 pounds.
|
|For that little weight, you're swatting flies with sledgehammers.
I don't see it quite like that.
|Lift it by hand.
Or perhaps an electric motor? I sort of like the crank-cogwheel-cogwheel
concept more.
|>|You'll want a chain wrapped around it and use the chain to do your lifting.
|>|There are all sorts of industrial lifting gadgets, including some fork lifts
|>|that incorporate a chain. That's what you'll want to emulate.
|>
|>Two bicycles are mounted in tandem, and the elevating platform rests
|>between the two. Since the contraption is intended for traveling into
|>a field and hoisting up booms with light fixtures at the ends of poles,
|>a cogwheel & rack arrangement ought to work well enough. It may have
|>been misleading to say it would be a forklift as opposed to an elevating
|>platform, but all I really want is for the thing to raise up about 3 or
|>4 feet above its base level.
|
|This sounds like an awful lot of work to misautomate a relatively
|simple and easily performed task.
Simple tasks get pretty tiring after doing the same thing, over and
over again. Since the lights have to be raised up to the same level,
over and over again, everytime we go to a new location, a physical limit
of some kind is highly desirable. Bicycles make setting things up pretty
fast, even if they are bolted in tandem. Ride to the location, raise the
booms (if they aren't already up, that is, which I sort of doubt), and
there you are. The expensive part is the rack, but I like the suggestion
of welding - maybe nailing - a bicycle chain onto the side of a board,
at strategic locations, and there we be.
