Jump to content
Light-O-Rama Forums
Sign in to follow this  
captainron19

Mega Tree Pole

Recommended Posts

Been using a telescoping flagpole for my mega tree for last 4 years - last year a wild wind storm broke my pole a couple of feet from the top. I was able to get back up and running with the same pole after I removed the damaged section and kept it lower

This year I want to go back to full height and was looking for any possible ideas to create some more support. I already have 3 guide wires in place but I was thinking about something inside the center of the pole like maybe some black pipe to provide some more support.

Does anyone have any input?

Share this post


Link to post
Share on other sites

Walter Monkhouse has an excellent design for a pole and portable hole. No guy wires needed.

Check out his site and click on the JUMP hyperlink.

He describes both the pole and how to make the portable hole. Be sure you are looking at the latest mods of both designs. I was just in Chicago at the Chicagoland Mini, and saw both, live in action. Very cool stuff.

The pole(s) he had at the mini were going up 30'. Plenty tall for a mega tree. Check it out

http://www.magicchristmas.org/

Share this post


Link to post
Share on other sites

jimswinder wrote:

what height you looking at?


I forget the exact height of the flagpole but it is about 20 feet I believe when fully extended

Share this post


Link to post
Share on other sites

I have been sitting here trying to think of what would cause a guy wired pole to break under the guy wire attachment point. I will email a structural engineer friend and ask.

Share this post


Link to post
Share on other sites

ainsworth wrote:

I have been sitting here trying to think of what would cause a guy wired pole to break under the guy wire attachment point. I will email a structural engineer friend and ask.

Seems to me that it has the potential to buckle under such weight (which flag poles aren't made for) if it starts to bend whatsoever. The top (where guyed) and bottom should move (if secured properly). But there is nothing holding the middle still. So soon as the wind pushes the middle of the pole slightly (thus bending the pole in the middle) it weakens the pole and it allows it to snap under the weight. The pole can sustain an axial load as long as the pole is straight. But such a pole is not designed for heavy bending load or shear load (I think that is the proper terms, but I am not an engineer so your friend will probably comment on this further).

Remember the school trick of how you can stand on an empty pop can if you step on it just right and don't move once there, but as soon as a friend would tap the middle sides of the can the can would crumble? Same idea I suppose.

That is why I suspect that if you guyed the pole in the middle also (or maybe 2/3rds up--again there is a calculation for this that engineers use) that would prevent enough lateral bend to help prevent snapping.

Share this post


Link to post
Share on other sites

zman wrote:

Walter Monkhouse has an excellent design for a pole and portable hole. No guy wires needed.

Check out his site and click on the JUMP hyperlink.

He describes both the pole and how to make the portable hole. Be sure you are looking at the latest mods of both designs. I was just in Chicago at the Chicagoland Mini, and saw both, live in action. Very cool stuff.

The pole(s) he had at the mini were going up 30'. Plenty tall for a mega tree. Check it out

http://www.magicchristmas.org/

Also I have information and videos on how to build the JUMP on my website. Also if you have any questions just ask.

http://www.brownchristmaslightshow.com/mega-tree.html

Hope this helps.

Jeremy B.

Share this post


Link to post
Share on other sites

black water pipe would work great, but is very heavy and usually quite dirty, but you can go with electrical emt pipe if you reinforce it a bit. Get two pieces in the size you need for the center pole and two pieces in the next smaller size. plus a coupler for the larger pipe. Cut one of the smaller pipes in half and put it down inside one of the bigger pieces so that you can stagger the smaller pieces inside of the larger piece, this will beef up the overall strength and the center at the coupler where you need it most.

Share this post


Link to post
Share on other sites

I used aluminum pipe...two pieces.

Bottom piece is about 13' tall 2-1/2" diameter.

Top piece is about 10' tall and I believe is 2" diameter (whatever fits snugly into the bottom pipe).

About 3' from the bottom of the 2" pipe I welded a collar (made from a small piece (about 2") of the 2-1/2" pipe) so that the 3' feet of the 2" top pipe slides into the 2-1/2" bottom pipe.

Even though it is 20' tall put together, it is very easy to lift up and put into it's base.

I do not even bolt the two pieces together as the weight of my Weber Tree lights (about 160 lbs) will keep it from coming apart.

BUT...it is very expensive...cost me about $200 for both pieces.

Share this post


Link to post
Share on other sites

here is the response I got;

[align=left]There are a lot of unanswered questions here. But I can tell you what might have happened, not having the answer to those questions.[/align] [align=left] [/align] [align=left]1. There might have been an imperfection at that point of the break, or rust accumulated.[/align] [align=left] [/align] [align=left]2. If one does not use guy wires, the moment near the top is small, but gets increasingly greater along the pole until it is greatest near the bottom. Also, shear accumulates at the bottom only. But when guy wires are attached, there is shear at the point of each guy wire attachment and moment is greatest between the guy wires. That is why we put bands around towers where a guy wire is attached. [/align] [align=left] [/align] [align=left]With guy wires attached, the moment near the base is decreased. But now the moment below the guy wires is increased. If the pole is not strong enough to take that moment near the top, or if there was a weak point, the pole could fail.[/align] [align=left] [/align] [align=left]If there were no imperfections in the pole, the fellow needs a thicker pole or one with a larger diameter.[/align] [align=left] [/align] [align=left]Can't wait to see this year's display![/align] [align=left] [/align] [align=left]Jacob

So, I would say you have the right Idea in making the top section thicker

Bruce
[/align]

Share this post


Link to post
Share on other sites

ainsworth wrote:

[align=left]If there were no imperfections in the pole, the fellow needs a thicker pole or one with a larger diameter.[/align]

I found a message in my SPAM folder that told me the same thing!

Share this post


Link to post
Share on other sites

Steven wrote:

I found a message in my SPAM folder that told me the same thing!

1511767.GIF

Share this post


Link to post
Share on other sites

Here's a few pictures of my 20 foot mega pole setup.It is just about 24 foot to the top of my 3 foot star.I also made the star with 2 blue ropelights.2 inch galvanized pipe.

Dans007.jpg

Dans013.jpg

Dans010.jpg

Dans023.jpg

Share this post


Link to post
Share on other sites

Hey Wally, are you a ham radio guy? 'Cause that's a JinPole we use to put up antennas.. never wudda thot of using it for a Mega Tree

TJ, NS2E
Amatuer Extra

Share this post


Link to post
Share on other sites

No.Just a farmer.I have never seen one like this.I just wanted an easy way to put on my star.

Share this post


Link to post
Share on other sites

I salvaged some 4 inch aluminum conduit, then attached a winch and pully system through the inside of the pole, added a ring on the top and just winch my lights up when they are all attached. I guy wire it so it doesn't move in our high winds. I had 8400 lights hung on it last year, it never moved. I am at 22 feet. We stick it in the ground with a construction fork lift last year. This year I will use a tripod of 4 X 4's, and over 10,000 lights.

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this  

×
×
  • Create New...