ONE
OF MANY WAYS TO LAY OUT A DUCT IN A HALF HOUR (!)....
IT WORKS
FOR THE WEBERS!!
(A
special thank you to Verdon for spending his Sunday morning on
the computer with me to accomplish this page!)
Regardless of what type of duct
you want to end up with, it's in your best interests to
find the easiest way to do it and yet the most efficient
for your crafts overall speed! This particular duct was
the beginning of the Weber WIG duct.....
Start with a good disc.......you
can make one yourself, or get a template.....it should be
collapsible for easy removal when your duct is completed.
It's time to lay out the strips
of beadboard...here Vernon uses 1" and is literally
strapping them together with inexpensive masking tape.
This particular duct requires
four lengths of varying widths of 14 1/2" to 5
1/2", all four can be taken out of one 4' x 8' sheet
of 1" beadboard. Since you need 2 of each length,
you will need two 4x8 sheets to complete it. It makes a
completed duct of 19" in depth.
Apply several beads of Great
Stuff as you wrap each layer, but not including the very
first layer....see next picture.
This is applying first layer
which has no Great Stuff applied to it. Each succeeding
layer will have to be glued.
The masking tape you see has
been applied to prevent breakage during bending.
Two small ropes will then be applied
around the unit and tightened and clamped to hold
everything tight, then short layers of tape are applied
to hold the ends together when you remove the ropes.
Forgive the finger here because I'm pointing so the
cameraman can focus on Vernon's activities....but he
didn't catch the hint!
Before applying second layer,
ONE rope will need to be removed and nails inserted four
inches above the trailing edge of the first layer to rest
the second layer on.
(note
the nail in the picture)
Second layer is applied resting
on the nails and tied together with one rope.
Third layer being applied to
rest on nails inserted in second layer 4 7/8" above
trailing edge and tied together with just one rope.
Another view of third layer
being applied.
Fourth and final layer evened up
with the leading edge of the third layer and tied with
rope to secure....no nails needed here. We leave one rope
on each layer until everything is set up.
The duct is slipped on a spindle
so that it can turn for glassing and shaping.
The inside surface aft of the
disc is glassed, a heavy bar is used to stabilize the
duct during glassing and just merely rests against the
duct.
Shaping the leading edge is done
with a special tool chucked in an electric drill...
which has been tooled to the
final shape we want the leading edge to be.
Inlet radius rough
finished....hot wiring of the rest of the outer surface
has already been done.
Initially when applying masking
tape be sure to apply it where it will not interfere with
the hot wire.
Masking tape
does not hot wire readily.
Duct is now removed from spindle
and hand sanded.
...and wallah, after a little
more coaxing we will have THE END of a StarCruiser!