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Here is what I see with the use of any form of aluminum pole. And this is to also include EMT, Rigid electrical conduit and those cheap TV antenna poles. All are of a thin wall material that easily flex. When a pole has loading from the ends. Eventually a weak spot will allow the wall to stretch and flex. As for the pin. Like I said in my earlier post. This pin will survive any thing you can throw at it. It will be the pipe that fails first. If you think you can just bypass the pin and use a pipe coupler. I would not do it. This will become your weakest point on the mast. Remember that the threads are cutting into the pipe and you have lost some of the strength that comes with the wall thickness. Might even consider cutting off the threads before installing the pin.

 

Beeiilll and Greg Young make a lot of great points. And Jimswinder has been very helpful too.

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I had an issue with the pin

. it did not fit tightly in the hole causing the top ten foot section to tilt a tad.

Not a big deal, but it did annoy me that it was not perfectly straight. No issue with the lights hanging down.

If I had a choice between 20 feet pole or two tens, I would go with the one piece for that reason. 

 

And as long as we are on the subject, did any pin users have this issue? any fixes? 

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I had an issue with the pin

. it did not fit tightly in the hole causing the top ten foot section to tilt a tad.

Not a big deal, but it did annoy me that it was not perfectly straight. No issue with the lights hanging down.

If I had a choice between 20 feet pole or two tens, I would go with the one piece for that reason. 

 

And as long as we are on the subject, did any pin users have this issue? any fixes? 

I had just the opposite experience...I used 2 pices of black pipe and I had to file the weld down to get the pin to go inside and I have to lubricate the pin each year to get it in (It's more than snugG (LOL)...I think it's the Chinese Pipe we import and there tolerences arn't that exact

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Here is what I see with the use of any form of aluminum pole. And this is to also include EMT, Rigid electrical conduit and those cheap TV antenna poles. All are of a thin wall material that easily flex. When a pole has loading from the ends. Eventually a weak spot will allow the wall to stretch and flex. As for the pin. Like I said in my earlier post. This pin will survive any thing you can throw at it. It will be the pipe that fails first. If you think you can just bypass the pin and use a pipe coupler. I would not do it. This will become your weakest point on the mast. Remember that the threads are cutting into the pipe and you have lost some of the strength that comes with the wall thickness. Might even consider cutting off the threads before installing the pin.

 

Beeiilll and Greg Young make a lot of great points. And Jimswinder has been very helpful too.

I am on version 3.0 of my mega tree, this version (which I used last season) starts with a 10ft piece of 2" rigid EMT.  I then took a piece of 10ft piece 1.5 rigid EMT and wrapped it in several places with Duck Tape so that when I slid it in it was a snug fit.  I then placed three eye bolts thru where the 1.5 slides into the 2 inch piece and use these for guide wires at the mid section.  I have a WowLights star topper and use guide wires with it (this is being replace with a hook head this year).  Do you see any issues with this setup?  It survived 50mph winds this past winter with no issues.

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Here is what I see with the use of any form of aluminum pole. And this is to also include EMT, Rigid electrical conduit and those cheap TV antenna poles. All are of a thin wall material that easily flex. When a pole has loading from the ends. Eventually a weak spot will allow the wall to stretch and flex. As for the pin. Like I said in my earlier post. This pin will survive any thing you can throw at it. It will be the pipe that fails first. If you think you can just bypass the pin and use a pipe coupler. I would not do it. This will become your weakest point on the mast. Remember that the threads are cutting into the pipe and you have lost some of the strength that comes with the wall thickness. Might even consider cutting off the threads before installing the pin.

 

Beeiilll and Greg Young make a lot of great points. And Jimswinder has been very helpful too.

aaahhh.. Max.. I am a bit confused by your first two sentences..   Are you talking about aluminum conduit?  I wasn't aware of any aluminum rigid conduit...  Regular rigid is the same as galvanized water pipe except for the threads are not tappered.. I believe..   That is what I use and it is plenty strong..

I also use the pole piece from CLS and I ground a "flat" on the pole piece so it will insert in the pipe without the pipe seam being an issue.. that pole piece goes up far past the threads and seems plenty strong.  Not sure the threaded part would really have much to do with the strength.. at least from what I have experienced..  have you had problems with any of them? 

I am on version 3.0 of my mega tree, this version (which I used last season) starts with a 10ft piece of 2" rigid EMT.  I then took a piece of 10ft piece 1.5 rigid EMT and wrapped it in several places with Duck Tape so that when I slid it in it was a snug fit.  I then placed three eye bolts thru where the 1.5 slides into the 2 inch piece and use these for guide wires at the mid section.  I have a WowLights star topper and use guide wires with it (this is being replace with a hook head this year).  Do you see any issues with this setup?  It survived 50mph winds this past winter with no issues.

Caniac,  Did you use EMT or Rigid?  Not the same thing..

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aaahhh.. Max.. I am a bit confused by your first two sentences..   Are you talking about aluminum conduit?  I wasn't aware of any aluminum rigid conduit...  Regular rigid is the same as galvanized water pipe except for the threads are not tappered.. I believe..   That is what I use and it is plenty strong..

I also use the pole piece from CLS and I ground a "flat" on the pole piece so it will insert in the pipe without the pipe seam being an issue.. that pole piece goes up far past the threads and seems plenty strong.  Not sure the threaded part would really have much to do with the strength.. at least from what I have experienced..  have you had problems with any of them? 

Caniac,  Did you use EMT or Rigid?  Not the same thing..

Rigid, thought it was Rigid EMT or at least that is what the dude at Lowe's called it. 

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aaahhh.. Max.. I am a bit confused by your first two sentences..   Are you talking about aluminum conduit?  I wasn't aware of any aluminum rigid conduit...  Regular rigid is the same as galvanized water pipe except for the threads are not tappered.. I believe..   That is what I use and it is plenty strong..

I also use the pole piece from CLS and I ground a "flat" on the pole piece so it will insert in the pipe without the pipe seam being an issue.. that pole piece goes up far past the threads and seems plenty strong.  Not sure the threaded part would really have much to do with the strength.. at least from what I have experienced..  have you had problems with any of them?

Sheese........Sur' wish I would of thought of that..... I'm embarrased to say how many hours I had filing the freakin weld down inside that pipe

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Rigid, thought it was Rigid EMT or at least that is what the dude at Lowe's called it. 

 

By Rigid EMT he means galvanized pipe sold at electical supply houses. It is the same as plumming supply stores except it comes in 10' lengths (electical) instead of 21' (plumbing). Rigid conduit has the same taperd NPT threads as galvanized plumbing pipe.

 

EMT (electrical metal tubing) is thin wall steel pipe used only for electrical conduit.

(and Mega Tree's)

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I agree with Tom, EMT is usually the thin walled stuff. Tell me this gents, can you put galvanized pipe in a bender (heavy duty type) and pull a 90 on it? You can with the rigid conduit that we use in electrical wiring. I think that the two are different metals or heat treating. One is malleable and the other is not. Sure galvanized pipe will flex a bit, but suspect that it would split, crack or fold if you tried to bend it.

As for the aluminum pipe, we are talking about those telescoping flag poles or for bird houses. But there is conduit made of aluminum pipe also. And actually Plasma, I reread my post and I believe that there is a period between the aluminum poles and all of the other pole materials. So, I am kind of confused about your confusion. And about my comment about the pipe threads. If the pin should be a wee bit loose inside the pipes. At what points does the pin press against the inside of the pipe? Those points would be the very end of the pipe and about what 6 or 8" inside of the pipe, at the end of the pin. Ok is going to happen when the pipe receives flexing forces at the joint. Cause the pipe is very thin in the first inch or so. I think what could happen is that the pipe will start to split at the end. This splitting starts a rift that weaks more pipe material further from the end. My thoughts are to cut off this weak area so if a split is going to start, it will have to do so at the full thickness of the pipe not at a thinner threaded area. Maybe I am anal, but I made it through one year and we had a very windy day that had my light strings making like a sail. And as I said I only have 12 channels that make 24 runs from top to bottom. Each run is made of 3 strings of C6 lamps 50ct each.

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I agree with Tom, EMT is usually the thin walled stuff. Tell me this gents, can you put galvanized pipe in a bender (heavy duty type) and pull a 90 on it?

 

Yes.  It's done all the time.

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I am on version 3.0 of my mega tree, this version (which I used last season) starts with a 10ft piece of 2" rigid EMT.  I then took a piece of 10ft piece 1.5 rigid EMT and wrapped it in several places with Duck Tape so that when I slid it in it was a snug fit.  I then placed three eye bolts thru where the 1.5 slides into the 2 inch piece and use these for guide wires at the mid section.  I have a WowLights star topper and use guide wires with it (this is being replace with a hook head this year).  Do you see any issues with this setup?  It survived 50mph winds this past winter with no issues.

Caniac,

How far down into the 2" EMT do you slide the 1.5"?

Edited by Klayfish

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I plan on using the Monkhouse Portable Hole: http://www.magicchristmasnews.org/portable%20hole%20ii.pdf and then use 2) 1 1/4" x 10' Rigid conduit with CLS 12" Pole Pin: http://www.christmaslightshow.com/pole-pin.html

(I am trying to get away from using PVC (gray or white). I had several pieces break during take-down this passed year)

I was not planning on guy wires, but after reading this forum, I'm re-thinking that.

 

On the Monkhouse portable hole, he tested his mast (pg.7) at 20' and over 70#s pull and it only flexed. He is, however using his designed "Jump Pole", http://www.magicchristmasnews.org/monkhouse%20jump%202010%20version0001.pdf which uses the Pipe in pipe method. I may rethink my 2 pole idea and go with the Jump version.

My tree will be ~20ft with 80 strings of 70ct lights. I live in TN and we do occasionally get snow or ice, but rarely. We do get some high winds from time to time.

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I am on version 3.0 of my mega tree, this version (which I used last season) starts with a 10ft piece of 2" rigid EMT.  I then took a piece of 10ft piece 1.5 rigid EMT and wrapped it in several places with Duck Tape so that when I slid it in it was a snug fit.  I then placed three eye bolts thru where the 1.5 slides into the 2 inch piece and use these for guide wires at the mid section.  I have a WowLights star topper and use guide wires with it (this is being replace with a hook head this year).  Do you see any issues with this setup?  It survived 50mph winds this past winter with no issues.

 

I have almost the same set-up just 1 size smaller pipe.

I use 2" on the bottom then 1 1/2" and 1 1/4" on top.  Each pipe slides in about 1 foot into the larger piece.

The 1 1/4" fits pretty snug into the 1 1/2"

3 Eye bolts are slid though the connection point for guy wires.

 

This allows me to hang all the lights from a short ladder and then 2 of my strongest friends help lift the center pole to full height.

 

Then we lay on the ground and huff and puff while we catch our breath and swear this is the last year we do it like this.

At least, that's the way it's been for 7 years now.

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Caniac,

How far down into the 2" EMT do you slide the 1.5"?

4-5ft

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I have almost the same set-up just 1 size smaller pipe.

I use 2" on the bottom then 1 1/2" and 1 1/4" on top.  Each pipe slides in about 1 foot into the larger piece.

The 1 1/4" fits pretty snug into the 1 1/2"

3 Eye bolts are slid though the connection point for guy wires.

 

This allows me to hang all the lights from a short ladder and then 2 of my strongest friends help lift the center pole to full height.

 

Then we lay on the ground and huff and puff while we catch our breath and swear this is the last year we do it like this.

At least, that's the way it's been for 7 years now.

mine is a little easier, I use the Monkhouse Portable Hole II.  200+lbs of concrete, on its side, hook the lights to the top and slowly move it upright.  I number my strands, takes a little extra time to unravel but not much. 30mins and it is up.

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mine is a little easier, I use the Monkhouse Portable Hole II.  200+lbs of concrete, on its side, hook the lights to the top and slowly move it upright.  I number my strands, takes a little extra time to unravel but not much. 30mins and it is up.

 

Do you hang the lights with it fully extended?

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Do you hang the lights with it fully extended?

yep, have it laying on it's side.  hook the lights to the topper and then flip it up.  I take a 6ft level to  use as a guide from the center pole and start with strand one, strand nine, and whichever number is to the left and right, then fill out the "pies".

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My answers one at a time in order of appearance.

  • Yes, a single 20' piece will flex more than a 10' piece but it is STILL stronger than any coupling, fitting or pin, with the exception of professional welding.
  • guy wire is needed. For a 20' 3 wires near the center are fine. Place them in a triangular pattern
  • A concrete foundation is HIGHLY recommended. Mine is 18" in diameter and 42" deep. I used a PVC sleeve so I can easily pull it out, lay it down, install MT hardware and stand back up. (This is my flag pole for the other 11 months)
  • Yes, a mega tree will still make a sound. Especially if it hits the power line and your neighbors tv goes out. Then you WILL hear it.
  • Aluminum or PVC is just asking for trouble. Wind and ice loads are only 1 factor. Weight is another and heat. As metals expand they become weaker. Yes, even up north. Direct sunlight can do amazing things.
  • A piece of rebar pounded in the ground may or may not be a good anchor. There are two factors to consider. What size rebar and what type of soils. Never use anything less than #5 or #6 bar. For sandy and/or dry soils you will need at least 3-4 feet driven at no less than 30 degrees. For clayey or well compacted gravels you can get away with less. The easiest way is drive it a couple feet, then if you can move it more than an inch, drive it more.
  • Max Paul, Beeiilll and Greg Young make a lot of great points. And Jimswinder has been very helpful too
  • VERY IMPORTANT - Yes, galvanized pipe is bent at 90's all the time, but it used for gas or water and IS NOT used to support a mega tree. You can bend these pipes and bury them or secure them to a wall, truss or stud in a building. However, when they are heated  they lose structural integrity. Remember gas and water steel pipe are not built for structural applications. They are built to last for many years before they are ruined by corrosion.

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