Megatrees
Here's an article from the February 2007 issue of the PlanetChristmas
newsletter.
Megatrees By
Darryl Brown
What Are Megatrees?
If
you frequent the PlanetChristmas
forums
then you will know there have been a ton of post about these megatrees and
it can be a bit confusing. There are really only two basic types of
megatrees, one that go all the way to the ground and the other is a tree
with a trunk (as seen in picture to the left.) They seem to be as small as
6’ and over 100’ tall.
A short definition of mega is as follows; “great,
extended, powerful.” In my personal humble opinion a mega-tree starts
at 20’ and goes up from there.
Getting started
Okay, to get started we need to know how high we want to build the
megatree. Once
we know how high we can easily figure out the diameter of the bottom.
Diameter is figured by dividing the height by two. So for this
megatree we will be talking about a 20’ tree. If you follow these
guidelines you can apply it to almost any size tree. For a 20’ tree we will
need a 10’ base (20'/2=10').
The Base?
There are two ways to build a tree, one is having the lights go all the
way to the ground and attached to a ring or build a base that will give your
tree the shape with a trunk and/or a skirt. If you would like for your
lights to go all the way to the ground, this is the simplest way. You
can go buy some gray electrical PVC pipe at the home center.
Now we need to do the math. If you are not good at math open up your calculator on your computer, click on the view tab and select “scientific”,
this will give you more options. I am going to show how to figure the amount of PVC pipe you will need to get a 10’ diameter.
The area around the circle is called the circumference. To find the
circumference, enter you diameter (10') and then multiply it by Pi (3.1416).
You should get the figure 31.42. This number represents the number of
feet in PVC pipe that you will need. Since PVC pipe comes in 10’ lengths we
can round the number down to 30’ and use three lengths of gray PVC pipe. I
recommend 3/4" or 1" pipe. When you get your electrical gray PVC you
will notice that it is really flexible and has a built in coupling. Now
connect the PVC end to end and you will have a nice complete circle with a
diameter to match the height of the tree. To hold this down on the ground
you can make some U shaped anchors out of ¼” rod to drive in the ground.
This is important otherwise the wind will blow your strings and possibly
get them tangled. Once the ring is secure, you can run your strings from the
top of your tree to the bottom, space them out accordingly and tie them down
using a zip tie. I recommend that you look for 5" reusable ties. From my
experience they can be removed much quicker then regular ones that have to
be cut off and you can reuse these next year, plus they have UV protection
built in. Now if you want to build a base to hold all the lights in the
shape of a tree with a trunk you can
click here for some free plans.
Center Support Pole
What
you will use depends on your budget. Some have used wood, galvanized
pipe, PVC pipe or a flag pole. Whatever you use needs to be set in
concrete. Right off the bat I want to say, using PVC for 20’ or higher
is looking for disaster. Once you get past 15’ in the air, everything
changes. Your PVC becomes more wobbly and the wind can be more fierce.
My first year building a mega tree, I used a telescopic flag pole from
Sunsetter Flag Poles. It was a 20’ pole. The drawback to a telescopic
flag pole is that it gets smaller at the top. Think of it as the telescopic
antenna that pulls off a radio. The top piece is the section that always
breaks off. The telescopic flag pole is not that weak, but it is the
weakest where you need the most strength. It will work, but you are
limited to the number of light strings you can use because of the total
weight. I used 128 strings of 100 mini lights (lighted length 33’) on
my first year tree using a telescopic pole and it was too much weight for
the top segment to handle. Your average 100 mini string weighs about 1
pound, so that totals 128 pounds pulling down on the top section. All
that weight caused the top section to slightly show a bend. To resolve this
problem we lowered that segment about three feet into the section just below
the top section.
In the picture at the top, Wayne Kremer used 1.5” (2” OD) galvanized
pipe. He put a 3” nipple cemented in the ground. You can read in detail how
he built his at his
website.
The most important thing is to guy wire the center pole. Some have
used three guy wires and others have used four. I say the more the
better. After my experience with extremely high winds in 2005, I feel
like somewhat of an expert now. We had high gusts of wind come through
and destroyed most of our display three days before the show started.
We got everything back up and got even worse winds the next day. You
would have thought we were safe and this should not happen again, but the
winds came a week later and were the worst ever, but this time we beat the
wind. So that is why I say you cannot have too many tie downs.
If you get lazy and try to take the short cuts, you will have problems.
So a little extra work is like insurance and will help you sleep better at
night. I personally use four guy wires. Even more important than
guy wires are the stakes that hold them into the ground. The stakes need to
at least be 18” long. I personally try to go 24” or deeper. There is
no such thing as overkill.
The Tree Topper
The
tree topper is what holds the light strings. I made mine using a bun
foot (round piece of wood), metal floor flange and a piece of 1.25” pipe,
you can see the details by
clicking here. Since Wayne K. used 1.5” galvanized pipe he was
able to screw the metal flange on to the top end of the pipe.
How Many Lights
The
amount of lights comes down to preference, power and/or budget. I
prefer to have as many lights as possible. You can never have too many, but
as a general rule I like my lights to be spaced 3" to 4" (I recommend not
going over 6" in spacing) apart. To figure how many lights I want on my
tree, I take the circumference of the circle, which we figured out earlier
by multiplying the diameter times Pi (3.14159). Earlier we came up with just
over 31' and decided to reduce it to 30' since we could use three - 10'
lengths of gray PVC pipe. Now let's take 30 (feet) x 12 (inches) = 360
(inches), then divide that number by 3 (inches) (our desired spacing) and we
come up with 120 light strings.
Computer Control

If you are going to hook this tree up using computer control (light
controller) this can also affect how many lights you will have, so we will
have to either round up or down the figure we came up with (120 sets of mini
lights) earlier. First we need to figure up how many amps we are going to be
pulling. Mini lights can pull anywhere from 0.22 to 0.42 amps. I will
use an average figure, lets say 0.32 amps. So 0.32 amps x 120 = 38.4 amps.
This tells me that I can get away with one light controller if I wanted too,
but I think I am going to use two light controllers, because if I use 16
channels, then one channel (slice of the pie) will be 22.5" wide. I came up
with this figure by dividing 120 (mini light set) by 3" (spacing between
lights). There is really nothing wrong with that width except that I cannot
make that channel width smaller if I wanted too. In this case I will go with
32 channels and my width will be half of that. 11.25. But now this averages
3.75 light strings per channel. This is not going to work so it looks like
we will round it up to four light strings per channel which will give us 128
light strings total when we multiply 4 (strings) x 32 (channels).
The
World's Biggest Christmas (Mega)Tree
Indianapolis, Indiana. claimed to have the world's biggest Christmas tree
in 2007. They use a monument that was 284' tall. Supposedly it is 15'
shorter then the statue of Liberty. I would have liked this tree
better if they used a center pole rather then a statue. The biggest I built
is a 40' tree.
Click here to see the video.
Click
here to see the
YouTube Video.
Suggestions
If you are going to start with a 30' or higher tree and have never done
any type of tree I highly recommend that you start with a 20' or less to get
some experience. I was a little naive with my first tree. I used 10"
anchors in soft ground and got lucky one night and walked out just as the
wind pulled one out. Another thing about the wind...it does not sleep.
The Mega tree is the central piece in your display, please don't try to take
short cuts, it will ruin your Christmas and disappoint the people that come
to see your show. Good Luck and if you have any questions please
email me, Darryl Brown.
A special thanks to Darryl Brown for submitting this story for our
newsletter.
Anthony Vetrano also has a great Megatree calculator.
Click here if you have Microsoft Excel
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