Is bigger better?

Cootamike

New elf
Joined
Apr 27, 2014
Messages
16
I'm already planning next years display and my major addition will be a mega tree.


My question is on size, i'm toying with a few designs anywhere between 4m and 9m tall.


My current thought is for a 360 degree tree 9m from ground to top ring with the option of a star on top next year. 16 x 8m of ray's pixels at 100mm spacing attached to 2mm galvanised wire to a 2.5m ring at ground level.


I'll program it as if it had 32 strings and just patch every second one in so I can easily double the strings later on.


The base will be cemented in to the ground and a tilt over plate will attach the top section and allow one person to put it up in a few hours.


I'm thinking size would be relative to the size of the yard it is in and we have a 1 acre property with a big front yard.


There is also a bit of a dick measuring contest going on with the people up the road a little who are on top of a hill and their static tree can be seen from 5km away.
 

scamper

Dedicated elf
Joined
Jan 5, 2014
Messages
1,225
Location
collie
Love it, any contest is a good contest :)

I would just be a little wary on the size as council regulations should be at least considered.
some councils wouldn't allow a structure of that size. I am not sure what it would come under, flag pole, or whatever.
I only say some consideration as no one will really care until someone gets their nose out of joint, and if a council receives a complaint, it must be dealt with.

another thing I would consider on a taller tree is, the extra weight, so lifting it into place and then securing it. you would need some serious guy wires as well.

But, if you have the space, and all the other things considered, then go for it, just make sure it is engineered well enough to put up with all the weight and wind loadings.
 

Fing

Full time elf
Generous elf
Joined
Dec 31, 2014
Messages
405
Location
Muswellbrook
I just built mine and a few observations.
1. Bigger is dearer....
2. power injection becomes an issue. mine is 5m strings injected at the bottom only, 8m *may* require injecting at the top as well
3. only do 360 if everyone can see all of it ( see point 1) mine is 270 and I think i could have gotten away with a 180
4. seriously consider buying pixel strips from James at Boscoyo
5. They can be surprisingly heavy my 36 string 50 pix 5m was about 30kg, which i winched up.
6. Don't under estimate the wind load on it
7. 9m high and 2.5 base I think will be to "tall and skinny" mine is 5m x 2.4m base and I wouldn't go any skinner. ( unless you want a tall skinny tree for your "competition" ( short and thick will do the trick... :p )
8. seeing as its xmas some kids might be getting new trampolines, look for the old ones, these make great tree bases ( Lizard Kings idea - these are known as Lizard rings lol)
9. if you have the space build two, then you can do "call and answer" sequencing :D
10. which ever way you go pixel mega trees are freakin awesome....
11 seriously, buy pixel strips...


cheers
Fing
 

lizardking

IT IS STILL ALL BENS FAULT
Joined
Dec 26, 2014
Messages
416
Location
Gold Coast
There is also a bit of a dick measuring contest going on with the people up the road a little who are on top of a hill and their static tree can be seen from 5km away.
if you build it they will come if you use pixels and want it to be seen just remember you can illuminate pixels to 100% the brighter the better lol when my 2.5 m tree flashes green at 100% you cant look at it from 5 m away its too bright as mentioned by other members 8 m strings you will need to inject at bottom middle and top to stop pixel fade i will post a pix of my 2.5 m and see what you think
 

Attachments

  • house1.jpg
    house1.jpg
    42.5 KB · Views: 43

Cootamike

New elf
Joined
Apr 27, 2014
Messages
16
In terms of wind loading and strength, what I'm looking at is a tilt-down radio tower from somewhere like this place: http://www.nbsantennas.com.au/masts_products.html

They need guying but nothing too heavy duty and they are designed to hold a heavy antenna in serious wind.

The base is actually my old 8ft trampoline. Lizard king's idea rubbed off on me.

On the pixels, I'm still thinking 360 degrees with the pixels pointing down so they can all be seen regardless of viewing angle and with 80 per string i should be able to just power from the bottom but I'll have the option of injecting at the top too if required. These are tge pixels I'm looking at: http://m.aliexpress.com/item/1932863171.html
 

Fing

Full time elf
Generous elf
Joined
Dec 31, 2014
Messages
405
Location
Muswellbrook
Cootamike said:
On the pixels, I'm still thinking 360 degrees with the pixels pointing down


I don't know for certain but does pointing them down lead to water ingress issues? most ones i've seen are pointed up with drip loops


other people may have a better idea but the 12v versions are less efficient as you are dropping the volts across a resistor to get it down to LED voltage, for this reason 5v pixels are often preferred


Cheers
Fing
 

Cootamike

New elf
Joined
Apr 27, 2014
Messages
16
mmmm, the 5v ones are actually cheaper....


It does make me rethink the number of pixels per string though, the voltage drop from 5v would be a bit more harsh than 12v


Fing said:
I don't know for certain but does pointing them down lead to water ingress issues?


Rain isn't much of an issue around here in December, they say their IP68 rated but that is taken with a heavy dose of salt however i'm happy with the risk.
 

i13

Dedicated elf
Joined
Jul 5, 2013
Messages
1,172
You don't need much water to do a lot of damage if your lights aren't sealed well enough. Some of my store bought lights are having that problem even in Adelaide's weather!

If the 5V is cheaper than 12V, recheck the number of pixels per string that Ray sells. Sometimes you're getting twice as many pixels when you pay more.
 

BundyRoy

Dedicated elf
Joined
Apr 9, 2014
Messages
1,026
Mike. Simple answer is yes. Doesn't have to be a lot bigger than the neighbours but it must be bigger. The ability to go bigger in future when your neighbours responds to the challenge would also be a plus.

On the 5v thing. Another option if you go 5v is use 12v power lines and use a buck convertor to go to 5v at the pixels. Buck convertors are cheap and it gives you a bit of room to move with voltage drop in the cables as you can lose a bit and the buck convertor will still have enough voltage to drop it to 5v. I'm sure there are some issues that need to be overcome. Water proofing the buck convertor is one and I don't think all buck convertors are created equal. I seem to remember reading that you need/should use a buck convertor that has some particular feature (maybe a fuse/isolating feature) but I can't remember what it is.
 

tooms

12v4life
Joined
Jan 2, 2015
Messages
208
Location
Kalgoorlie
Their is a guy on youtube with some videos, if you search for Johnson family Christmas lights you'll find them, he has 6 smaller pixel tree's .. I think they look neato.

2015 seems to be the year of the mega tree .. seems like everyone has one now, I was going to do one as well but didn't .. I think 2016 I'll steer clear of it as well and try and think up something else
 

fasteddy

I have C.L.A.P
Global moderator
Joined
Apr 26, 2010
Messages
6,648
Location
Albion Park NSW
Fing said:
other people may have a better idea but the 12v versions are less efficient as you are dropping the volts across a resistor to get it down to LED voltage, for this reason 5v pixels are often preferred


Cheers
Fing

This may not be the full picture as people are split between using 12vdc and 5vdc pixels based on what they perceive as important and what LED design they are using
The 12vdc version should run at around 10mA per pixel per colour instead of around 20mA (18.5mA for 2811) per pixels per colour, so efficiency is not really an issue here. But some of Rays 12vdc do run at the full 20mA which can be an issue due to the added heat that is dissipated. LEDs are linear in there dimming but the human eye is not, so we see LED dimming very easily at lower levels but when it comes to high intensity levels then we do not see the differences very easily so a LED running at 10mA instead of 20 mA may appear to be very similar in intensity to the human eye.
The other factor is the LED quality used, so if higher grade LEDs are used then the light output for 12vdc being driven at 10mA could actually have a much better light output than a lower quality 5vdc LED being driven at 20mA which I have witnessed on many occasions.

Both 12vdc and 5vdc have their advantages and disadvantages

12vdc has lower current used per watt which means less % of voltage drop over the same distance as 5vdc which means less power injection required
12vdc is less efficient if driven at the same current as 5vdc pixels and using the same LEDs
12vdc will let out less measured light but may appear similar to the human eye when driven at approx. 10mA using the same LEDs as 5vdc
Less power supplies and thinner gauge of cable needed with 12vdc when driven at approx. 10mA compared to 5vdc

12vdc is a compromise to allow for a more workable solution when dealing with pixels compared to 5vdc which is a better electronic design because LEDs used in pixels typically run at approx. 2.3 volts for red and approx. 3.2 volts for blue and green (this can vary) so that means less voltage needs to be dropped to drive the LED compared to that of a 12vdc LED

So both have there advantages and disadvantages, what needs to be decided is what factors are most important for the person choosing their lighting system.
 
Top