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(Note;
If you cut and paste the materials
needed list from the previous page
and print it out, you
will have an accurate shopping list to take to the hardware store. There are
other items needed to complete this entire project that aren't shown here, but
these are the items needed to build the entire mechanical portion of this event.)
The l-shaped sides for both sides
of your framework will be assembled
as shown above using the pocket
bore jig. Use a yellow wood
worker's glue in the joint and be
sure your cuts are square. Hold
your two pieces of wood down FLAT
to your work bench so
 your
joint is flat and square. Be sure
the screws pull up tight.
Here are both sides and the center piece that will attach them to each other.
 Between the lower legs of each side I will need a "foot" to stick
out forward that is exactly 1 5/8" wide like the above separator. To
achieve this I am gluing two 3/4" solid pieces of oak together and since
four quarter stock is actually a finished size of 13/16" thickness
(1/16" thicker than 3/4") this will equal precisely what I need. These
pieces are 2 1/4" wide by 15 1/2" long. You can clamp these together
not using any nails if you want. They will be dry enough to work with within one
to four hours depending on your temperature.
 I used a few staples in mine so I could work with them immediately and will
cut off one corner which will be at the top of the foot's end. While your glue is drying on the framework, you can turn to the
details of the mechanism. The strap hinge above shows how it looks like when you
first see it and on the left with one tongue cut down to 3/4" and a
 hole
drilled in the middle for a 5/16" bolt (the bike pump's air ram) to fit
through. As you can see, the hole will cut into a previous hole, but it will
still work just fine. Notice the other tongue is bent as we mentioned earlier to
a nearly 90 degree bend. This will give you the cavity needed underneath.
 Now we turn to the air ram. We will need to mount the base somehow to
the frame, so the way I chose is to use a section of one of the feet that is on
the bottom. You can cut this to 2 3/8" or even 2 1/2". This
"pin" will slide through the two holes that the foot used to clamp
into and into holes drilled in to each side of the
 framework.
 The placement of the 3/16" hole drilled for the pin is at 13
3/8" off the floor and 7/16" from the front edge of the frame. Drill
in about 3/8" to 1/2" deep. Make sure your holes are exactly the same
on both sides of the frame so the line up and leave the cylinder mounted square to
the frame.
At the end of the upright section
of the sides we will need to drill
some holes. Here you can see two large holes that are countersunk with the
1" forstner bit that will allow 5/16" x 3 1/2" carriage bolts
that will mount the top of the scissor to the frame to sit in flush. Also a
countersunk #8 hole for the screws we will be using to attach both sides of the
frame together. You will be drilling 6 of these from the top as shown (not right
at the end of the wood, as we don't want our pieces splitting out) to just above
the foot section below.
 A close up of the scissor attachments show the hinge already in place. With
my air ram, the perfect spot to attach this was at 15 5/8" from the end on
center to the pin of the hinge itself. You should put your entire mechanism
together and place yours where it needs to be to allow your scissor to be fully
folded down with your air cylinder standing vertical. Once attached, if your cylinder has
the same throw as mine did, your lower or the two parts of the scissor shown
above should lift up to perfectly horizontal.
Also shown above is the connection of the scissor to one side of the frame
and how you will space this out to work with just enough clearance to pivot, but
not allow slop. Drill your 5/16" holes at 3/8" from the end of each
tube aluminum, on center to the tube. Be sure your holes are drilled square to
itself, or they will be lopsided in the frame. It is best to use a drill press
for these holes. And remember also to keep your holes drilled through each side
of the frame to be perfectly aligned with each side too. If you attach both
sides of the frame to each other temporarily with some screws you can drill
these holes together at the same time, insuring perfect alignment. The
attachment of the scissor on the bolt will be; flat washer / nut / flat washer /
tube aluminum / flat washer / nut / flat washer. This should space out to
precisely 1 5/8". If it does not, use more washers or thinner washers to
achieve a perfect dimension to 1 5/8" before putting the final side of the
frame on.
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