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I bought the 20' mega tree kit from CLS. I bought a 21' piece of black pipe to use as my center pole. Is the pole stronger as one 21' section or would it be stronger if I cut the pole on half and used the pole pin that came with the kit?

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What is the "Pole Pin"?

 

Is it just a smaller diameter pipe that would fit into the two cut pieces of pipe? If so, how long is it?

 

EDIT:  Never mind..Googled it...

 

It certainly would be stronger where the pin is, just on the basis that you have more material...but I think you would need guy wire both at the top and in the middle of your mast or else it could still buckle in the middle under the right circumstances...from the voice of experience...  ;)

Edited by jimswinder

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I would think 1 piece would be stronger.

I agree one piece is better. Don't cut it. The only reason for the pin is if you can't get one piece long enough.

 

I agree with Jim on guying it at the top and middle whether it is one piece or cut.

 

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It certainly would be stronger where the pin is, just on the basis that you have more material...but I think you would need guy wire both at the top and in the middle of your mast or else it could still buckle in the middle under the right circumstances...from the voice of experience... 

 

Jim,

What type of pipe where you using and what size that you had problems?

 

Mike

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...from the voice of experience...  ;)

 

I remember that "ah sh_t" moment, Jim was none too happy that day.

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I have used a pole pin and two 10' sections of galvanized for the last two years. We had some pretty windy days (gusts over 50mph) during that time and I only guy mine at the top.  I have had no issue what so ever.  YMMV of course.

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If a mega-tree falls and no one hears it does it still make a sound?

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I have been using a single 21' piece of pipe for my tree for the last 4 years with no problems.  I have 4 - 3/16" steel guy wires on the top of it (I use the mega tree kit from CLS as well) and have seen up to 65 MPH gusts on the tree.  I have 96 strings of C6 LEDs on it as well as some strings of strobes inside it.  It has not moved a bit during any wind or snow storms.

 

The single lenght of pipe will be stronger overall than cutting it and using the sleeve and pin in the middle.  While the middle might get a little bit of extra strenght to it by the sleeve, cutting the pipe introduces a "weak point" in the overall strenght of the pipe.  If you were to cut it, then you would want to use guy wires at the center point so that it would not want to flex at that point from wind and whatever.

 

You will want to make sure that the pipe stands as vertical as possible as well.  Every little bit that it is off from truely plumb and vertical will introduce stress on the pipe, so keeping it as straight and true upright is the best thing to do.

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Jim,

What type of pipe where you using and what size that you had problems?

 

It was 2-1/2" Aluminum pipe...but I had a LOT of other pressures exerting themselves on my tree. I had what I called "Streamers" going from the top of my 9 Mini trees on the ground going to the top of my Mega tree on the top of my roof. Each streamer was about 60' long and consisted of 6 - 10' x 3/4" PVC pieces and each was wrapped with 4 strings of 50Ct LED's (RGBW)..plus the 3/16" cable that ran thru the streamer...so a lot of weight was being pulled on my tree in one direction.

 

You can see it here:

 

http://vimeo.com/21280597

Edited by jimswinder

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I have used a pole pin and two 10' sections of galvanized for the last two years. We had some pretty windy days (gusts over 50mph) during that time and I only guy mine at the top.  I have had no issue what so ever.  YMMV of course.

Same here....

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I bought the 20' mega tree kit from CLS. I bought a 21' piece of black pipe to use as my center pole. Is the pole stronger as one 21' section or would it be stronger if I cut the pole on half and used the pole pin that came with the kit?

 

What diameter is the pipe?  I would hope 1" or bigger.

 

I use 2 pieces of EMT for my tree.  1 1/2" and 1 1/4".  Holds 9,600 C-6 Leds but I wouldnt dream of it without gut wires.

3 on top and 3 in the middle.

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Good grief, lots of stuff some of you are doing I would never do. First is the last one. I would not use EMT or Alum. poles. At worse case I would only think about Rigid electrical conduit. I  agree one piece of 21' galvanized is stronger than 2 10' of same dia.  And even though the pin would make the joint stronger than say a coupling. I have to think that the pipe would split open before the pin would fail. Now as for the need of guy wires in the middle. When using the proper pipe material such as thick walled galvanized and 2 10' x 1 1/4". Then no middle guys are needed so long as you have 3 or 4 guys at the top and well snugged in. But thinking about this I will back up and say that if you have so much weight that you reach a certain point that you could overload and cause the pole to buckle in the middle. Be fine going up but ice loading could do you in.

Anyone trying to do a mega tree, even a 10' one with PVC or T.V. antenna pole is crazy, just plain crazy. I am a poor boy and cant afford to buy enough LED strings to make my 17' tree heavy enough to need mid guy wires. Currently only have 36 100ct strings. Even at 72 100 ct I dont think that I would have to worry.

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The first question you have to ask yourself is 'What are my conditions?', Environmental, winds, rain, snow, all that fun stuff that is unique to each region that we live in, even the neighborhood.  Every Mega Tree is going to be unique also, each of us will build the same tree differently dependant on our wants and skills.  Here's what I can tell you about my Mega Tree:

It's a total of 25' to the top of the 3' star, with 64 strings of minis, we get some rain, though generally not bad (I love Southern California), winds are a different story, during a normal season we will have 2-4 days/nights of 30mph with gust to 50+, in 2011, we got hit with hurricane force winds with gusts over 100 mph.  I have zero guy wires.  The winds generally come from the north and my stand is/was built with that in mind, I did get hit in 2011, with an easterly gust and the tree took the hit.  My base now is built to take the winds from any direction.  Now for the details, parts of which are thanks to Walter Monk.

The bottom of the base, are 5 legs made of 3" square tubing welded to a 6" center pipe (3" tall), it looks sort of like a star..  On top of this is a block of concrete approx 24" x 24" x 10", it weighs about 400 lbs and is clamped to the legs.  In the middle of the concrete block is a 24" piece of 6" pipe, towards the bottom of the pipe I have 3 5/8" bolts that come together about 3" apart for the bottom of the Mega Pole to go into.  Towards the top of the 6" pipe there are 3 more bolts that I tighten onto the pole and ensure it is plumb.  The bottom of the Mega Pole is 14' of 2 1/2" Galvanized Pipe, next is 10' of 1 1/2" EMT, that fits inside the 2 1/2" gal and I use a through bolt to connect the two pieces of pipe.  On top of the EMT, I attach the 3' star.

I will admit that I tend towards overbuilding, but I'm comfortable in knowing that damage is less likely to occur.  This is the biggest thing that I want to get across to everyone, Figure out what will do for your installation and then figure out how to build it better.

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Good grief, lots of stuff some of you are doing I would never do. First is the last one. I would not use EMT or Alum. poles. At worse case I would only think about Rigid electrical conduit.

 

That made me chuckle.

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What diameter is the pipe?  I would hope 1" or bigger.

 

I use 2 pieces of EMT for my tree.  1 1/2" and 1 1/4".  Holds 9,600 C-6 Leds but I wouldnt dream of it without gut wires.

3 on top and 3 in the middle.

I will be using a 21' piece  of 1-1/4" black gas pipe.

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Thanks for all the replies. I'm glad I asked the question, because it sound like the consensus is that the single 21' piece of 1-1/4" black gas pipe is better than two pieces joined by the supplied pole pin. I guessed wrong because when I stood the 21' section upright, I noticed some flex in the middle, which I would not expect with a piece that is 10.5'

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Black pipe does have some flex to it.  I hung more pipe than I care to remember and we always had some sag in full lengths.

You will still get some flex with 10.5' sections  but without a connector or coupling in the middle that can break.

 

Make sure you use good guy wires and secure to the ground well.

(P.S. A piece of rebar pounded into the ground at an angle is not a good guy wire anchor)

 

Good Luck and have fun!!

 

Scott

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It was 2-1/2" Aluminum pipe...but I had a LOT of other pressures exerting themselves on my tree. I had what I called "Streamers" going from the top of my 9 Mini trees on the ground going to the top of my Mega tree on the top of my roof. Each streamer was about 60' long and consisted of 6 - 10' x 3/4" PVC pieces and each was wrapped with 4 strings of 50Ct LED's (RGBW)..plus the 3/16" cable that ran thru the streamer...so a lot of weight was being pulled on my tree in one direction.

 

Thanks JIm That pole would have had to have really thick walls to hold up under all that!

 

Mike

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Thanks for all the replies. I'm glad I asked the question, because it sound like the consensus is that the single 21' piece of 1-1/4" black gas pipe is better than two pieces joined by the supplied pole pin. I guessed wrong because when I stood the 21' section upright, I noticed some flex in the middle, which I would not expect with a piece that is 10.5'

Guess I'll go against the grain.......I have the same kit from CLS that you have I've been using mine for 3 seasons now and for storage constraints I use 2pcs of black pipe  with their Pole Pin. I have 96 sets of 100ct lights along with their rotating star and I would guess that equates to about 100 to 125 lbs hanging off the top of that pole and we have had 60mph wind gusts many times. and the center pole stays about as straight as you could possibly want. so if it's easier for you to do 2pcs go for it without concerns. 

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Ha, no such thing as against the grain in this hobby!  I believe that the "think outside the box" style is why some of us do this in the first place.

Something that I wanted to throw in here was that while both methods (either a single 21' piece or 2 - 10 foot pieces with a sleeve and pin) will be acceptable for a center mast for a tree, the forces that can come into play with it are the biggest concern.   It may be easier for some to use or store the 2 pieces of pipe rather than 1 long piece so that can come into play as well.

 

I get more into the dynamics of the forces on the pipe as a concern.  If either the single or the two pieces stay absolutely vertical and don't move, then the load is the same.  Once you start to introduce any lean or sway into them, then the force on the pipe and the center connection point if using 2 pieces becomes more relevant.  As the pipe leans further away from true vertical, you begin to get concentrated force on the place where the 2 pieces are joined together more than on a single piece of pipe, although with enough lean (and/or weight) you can reach the point where that joint will fail before a single pipe would fail (but a single lenght of pipe an certanily buckle and fail as well).

Most of all it must be considered where the pipe or pole is located with respect to wind, weather, soil, weight of lights and materials, and how it is going to be guy wired off as to what will work and what will not.  Some folks can get away with an Aluminum flag pole while others may need a 2" galvanized steel pipe for the center pole.  Also some may only use 3 or 4 guy wires on the top while others may use 4 or more guy wires at the top and at the middle of the pole.

So anyone should make it a point to study all the factors before just tossing a 21 foot tall pipe out there and thinking that all is good with the world.  Not trying to scare anyone but a few minutes of study beforehand can save a lot of extra work or possibly a bad accident later on.  We also have to be careful because we all want to add more and more to our displays so while we may have a center pole that can handle the 30 strings ofs lights that we started out with, it does not take long before we are thinking of using 100 or more strings on that same setup.

I tend to overdesign to be safe but also so that I can make changes later on without any problems.

Just wanted to throw this "food for thought" into the conversation.

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Ha, no such thing as against the grain in this hobby!  I believe that the "think outside the box" style is why some of us do this in the first place.

Something that I wanted to throw in here was that while both methods (either a single 21' piece or 2 - 10 foot pieces with a sleeve and pin) will be acceptable for a center mast for a tree, the forces that can come into play with it are the biggest concern.   It may be easier for some to use or store the 2 pieces of pipe rather than 1 long piece so that can come into play as well.

 

I get more into the dynamics of the forces on the pipe as a concern.  If either the single or the two pieces stay absolutely vertical and don't move, then the load is the same.  Once you start to introduce any lean or sway into them, then the force on the pipe and the center connection point if using 2 pieces becomes more relevant.  As the pipe leans further away from true vertical, you begin to get concentrated force on the place where the 2 pieces are joined together more than on a single piece of pipe, although with enough lean (and/or weight) you can reach the point where that joint will fail before a single pipe would fail (but a single lenght of pipe an certanily buckle and fail as well).

Most of all it must be considered where the pipe or pole is located with respect to wind, weather, soil, weight of lights and materials, and how it is going to be guy wired off as to what will work and what will not.  Some folks can get away with an Aluminum flag pole while others may need a 2" galvanized steel pipe for the center pole.  Also some may only use 3 or 4 guy wires on the top while others may use 4 or more guy wires at the top and at the middle of the pole.

So anyone should make it a point to study all the factors before just tossing a 21 foot tall pipe out there and thinking that all is good with the world.  Not trying to scare anyone but a few minutes of study beforehand can save a lot of extra work or possibly a bad accident later on.  We also have to be careful because we all want to add more and more to our displays so while we may have a center pole that can handle the 30 strings ofs lights that we started out with, it does not take long before we are thinking of using 100 or more strings on that same setup.

I tend to overdesign to be safe but also so that I can make changes later on without any problems.

Just wanted to throw this "food for thought" into the conversation.

I learned this lesson the hard way, had a "cheaper" telescoping flagpole and overloaded it to the point it is now junk in a landfill.  Got a better one but am finding out it is not ideal for anything more than 16 strands of lights.  used 2" rigid EMT last year and that works great, will be  using 96 strands of light this year plus a topper.

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I learned this lesson the hard way, had a "cheaper" telescoping flagpole and overloaded it to the point it is now junk in a landfill.  Got a better one but am finding out it is not ideal for anything more than 16 strands of lights.  used 2" rigid EMT last year and that works great, will be  using 96 strands of light this year plus a topper.

Caniac - can I ask what your problem with the flag pole was?  I've heard multiple people suggest not to use them.  Was it just the telescoping portion of it?  Because I have a 25ft tapered (non-telescoping) aluminum pole (approx 6" on the bottom down to 2.5-3" on the top)...and I just can't see how this would be problematic, at least not due to weight.  I could see winds potentially bending it, but guy wires should fix that.  I plan on going with 96 strings right off the bat.

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it is four 5ft sections that start out at 2.5 inches at the base and taper up to 1.25 inches.  they use a push button spring mechanism to lock into place as you raise the pole.  when you are putting a flag on it this works great.  I put up and American flag 9 months of the year, October it flies a Jolly Roger, November-December some part of the Christmas show.  The issues I was have is that the weight of more than 16 strands of lights was more than the push button mechanism could handle, the first one I had was a Sunsetter and it was crap (or at least for a mega tree), have a Tel-a-Pole now and though it works better (thicker gauge aluminum and stronger springs), it still isn't ideal.

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The pole pin Darryl sells is a solid 8 inch long pin, which is divided euqally between the two10 foot sections of black pipe. There is no coupler joint per se, just a solid steel pin that both black pipes slide over.

The top of his tree is guyed in 4 directions (although 3 would have worked just as well).

More than a few folks have used his design over the years without any issue.

I doubt you would have any issue with it, assuming adequate guys at the top, and a good base.

Black pipe is pretty strong, as is galvanzied pipe.

I agree with the comments above to avoid pvc/EMT conduit if you are faced with any significant winds (and who among us isn't), as I have seen quite a few folks on the various forums report failures when using those.

Rigid conduit is fairly strong. I use that for the first 10 foot section of my pixel tree, with galvanized pipe making up the upper telescoping piece.

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