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Hard top hoist design

To: Allan Connell <alcon@earthlink.net>
Subject: Hard top hoist design
From: Steve Laifman <laifman@flash.net>
Date: Fri, 28 May 1999 10:54:43 -0700
Allan and Tigers,

I also built my own hoist, using swivel pulleys from
Home Depot, a manual worm drive winch from Harbor
Freight and Supply ($29), and a drill motor because
I am lazy.

Start with a bolt-on "J" hook on a beam above the
place where you want the corner of the side window
to be (that's the approximate  center of gravity (a
little behind, actually).  Put another about 4"
over.  These hooks have tow lag bolts attaching them
to the side of the beam. The center between the
hooks is where the center of the top will be,
laterally.

Hang a swivel eye 1/2" pulley off one hook, and tie
off a flat braided 1/2" smooth rope on the other
hook.  Thread the rope through another swivel
pulley, which will be the one you attach the top to,
and then back up through the "J" hook stud mounted
pulley.  From here, run the line to a "J"
hook/swivel pulley on your rafters at the
appropriate front or side wall.  The last "J" hook
should be at about a 45 degree angle to allow the
swivel to let the rope go down.

If you use this method you will have reduced the
pull force to half the top weight.  Using multiple
shive pulleys (not Home Depot stuff) you can
increase this significantly, but you can do it if
you were gloves.

I bought a screw type manual hoist.  This has an
advantage over the normal winch with the click stops
as it is self locking, and needs to be reverse
cranked to lower, instead of manually letting the
rope burn your hands.  It also has a very high gear
ratio and requires many turns for little movement.
A 1/4 inch reversible drill, with a 1/2" chuck, will
allow you do grab the shaft with the drill and do it
electrically at about 2/3 speed.  I have thought
about an old garage door opener motor and
transmitter/receiver and pulley/belt coupling to do
it remotely.

The top sling can be made from the same rope.  Using
a double strand, make a knotted loop on one end,
thread it under the top at the rear of the window
opening, and over the rain gutters to the snap hook
you attach to the hanging pulley eye.  Give enough
slack to prevent the rope from touching the top
paint.  Use a piece of garden hose, heater hose,
sponge hose from a/c line covers, whatever, to cover
the rope on the inside of the top and around the
gutters.  This protects that area from rope load
concentration,  Putting some rubber fuel line tubing
in the top rubber fold in the contact area prevents
collapse here.

Another alternative, if you can find one,  is the
old type car roof rack with rain gutter mounting
brackets.  An screw eye in the center will connect
to the snap hook. If you find a pair of really nice
ones, I'll buy the second one.

The top, when lifted, will angle very slightly to
the front.  This is good, because you don't want to
have it trying to slide off.  Mine is mounted with
the top front facing the garage door.  I hoist it
high enough to allow the top front edge to be above
the raised garage door.  Make sure of your distances
BEFORE you mount those first "J" hooks.  A soft
cover, like an old blanket, should keep the dust
off.  Clean and wax it before storage.

Good luck, and open to any ideas for improving this
do-it-yourself project.

Steve




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Steve Laifman         < Find out what is most     >
B9472289              < important in your life    >
                      < and don't let it get away!>

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