Re-inventing the scare light

[Lumatic]

Originally Posted by Zeppelinium

This is a lot easier than making a fixture for a segment of the LED tape. I'm thinking of using them in other places--compartment lights, shower, over the toilet...

Zep

I got 15' of LED strip from Amazon for less than $1 a foot. I thought I would play with replacing the bulbs in the longer light over the bed , but, I really don't know what the heck I am doing. Do I just cut the strip down to the desired length, secure it and hook up the positive and negative wires?

[Zeppelinium]

Originally Posted by Lumatic

...Do I just cut the strip down to the desired length, secure it and hook up the positive and negative wires?

In a word, yes. The strip is polarity sensitive, make sure you keep track of which side is positive before you solder on your color-coded wire (like red and white, or red and black). If you don't use a color code you WILL screw this up at some point.

The strip is marked at the acceptable cut locations, which is is every 3rd LED. Each of the little copper spots are where you solder on your wires. The spots are tiny, so use a small soldering iron.

If you got the waterproof version, you'll have to carefully slice the plastic and then scrape off the 0.1" at the end in order to get to the copper.

Z

[Zeppelinium]

Originally Posted by Zeppelinium

...Be sure you've got 1" clearance between your step (when the step is up) and top of the step well, or mount it further back in the well. The emitted light angle is fine for mounting it towards the back of the well. ...

PS--Despite the drawing showing the light emitting angle shining down, mount the fixture with the mounting plate UP, so the light shines OUT horizontally. You'd figure it out right away...Duh. Z

[vswingfield]

Originally Posted by Zeppelinium

...

PS--congrats on the use of wry. I looked it up (usage, not the word) and you're only the third person to have used it in the last 30 years.

I had some friends in the Texas Hill Country that had a bluegrass band named Wrygrass. It was in the late 80s/early 90s so it was in the last 30 years. But working its way towards barley in the last 30 years.

[Zeppelinium]

I moved the Safari back to the woods. I went out in the dark to check the light patterns and am completely satisfied. Here are my findings:

1. The over-door light on bright is pretty much in your face 30-40 feet out to the side of the Airstream and gives good ground illumination out 22-25 feet and all along the length of the Safari.
2. The over-door light in dim is not so annoying out 30 feet, so the neighbors won't come after you with pitch fork and torches, but still provides good light around the step and door.
3. The "party light" setting on the front marker lights can be easily seen from 1300+ feet away, even through sparse forest.
4. The light over the curb side window provides good illumination out 12 feet, plus the hitch and propane tanks, and the tow vehicle tailgate.

Totally happy,
Zep

[goshawks00]

we need pics!!;>)

[Lumatic]

Originally Posted by Zeppelinium

I moved the Safari back to the woods. I went out in the dark to check the light patterns and am completely satisfied. Here are my findings:Totally happy,
Zep

I wonder if that's how Close Encounters of the Third Kind was inspired.

[Zeppelinium]

Originally Posted by Lumatic

I wonder if that's how Close Encounters of the Third Kind was inspired.

No, I haven't installed the external speaker connections in the new "external connections" junction box where the scare light used to be. Plus, I don't have the right music ... yet. Z

[barts]

Ok, ordered some of those license plate lights... We're gonna have step lights this year. Of course, that means I have to blame demon rum (or Patron, Kob Creek or Bombay Saphire) instead of the infernal dark next time I take a tumble out the door.

- Bart

[Steve Bryant]

Zep,
I'm planning my order for LEDs now. I will do the step light and a couple of others soon while I'm reworking my steps and some other floor/belly wrap stuff. Then I'm going to go ahead and buy a weatherproof and indoor light strips for those future projects on my compartments, closets, tow vehicle and some other stuff.

BTW, this thread is moving at the speed of light!!! There's been so much activity here lately that it's smokin' hot...thus generating a kind of light that is seldom seen!

You da man!

Steve

[Lumatic]

Originally Posted by Zeppelinium

No, I haven't installed the external speaker connections in the new "external connections" junction box where the scare light used to be. Plus, I don't have the right music ... yet. Z

All you need is four quavers, a group of five quavers, and a group of four semiquavers and some big mother speakers.

[Zeppelinium]

Got my spotlights from Hong Kong last night, one day early. This is definitely a $20 light bulb in a $100 fixture, all for $12. It looks as good as its photo and, at 3" diameter, will look good in a temporary hangar on the side of the Safari.



The cord on mine has 3 wires. Two of them had a small amount of the lead stripped, and it turns out they are the power wires. No clue yet on wire number 3.

My meter says these are 6.5W (.48 A), not 10W, which is OK by me. When you take it apart you find a tiny circuit board wrapped in insulating tape and it looks like it has the A61 regulator. Despite this, the unit dims very nicely. I tried 35, 47, and 56 ohms, all of which produced reasonable amount of light. I'll use the 47 ohm resistor for dimming, which results in a current of 0.095 A.

The light pattern has a bright circle 15" diameter at 36" distance and a flood area about 80" diameter at 36" distance. I was able to double the diameter of the bright spot using a circle of sanded acrylic against the lens, but the larger flood area didn't change much. Still, hanging at mid-window height on the side of an Airstream, this little light will look good and provide good under-awning light. As a spotlight shining more out than down, it easily compares to the scare light. Two of these hanging out on the extended awning arms and you've got a party!

Zep

[Keyair]

Awesome!
That idea of putting some on the awning legs...
I like that!

The RGB version of the lamp has 3 wires.... mine only has 2...

For the electric morons out here(me!), can you give us a quick lesson on testing what the draw is on a lamp?

[Zeppelinium]

Originally Posted by Keyair

..The RGB version of the lamp has 3 wires.... mine only has 2...

For the electric morons out here(me!), can you give us a quick lesson on testing what the draw is on a lamp?

Mine is definitely warm white. Hmmm....

Testing current: Lots of small voltmeters have the ability to measure current directly. You jus hook it up in series with the light (selecting the right scale, of course). Be careful, these little meters (get one for $4 at Harbor Freight) usally have two current settings, 10 amp or 200 milliamps. Most of these LEDs we're talking about draw between 190 milliamps and .5 amps, so always start with the 10 amp setting. There is a little fuze inside on the 200 ma setting that will blow and then you lose all your current measuring capability, but all the other features will still work fine.

If your meter only measures volts and resistance, then you must have a resistor. Use the formula E=IR (volts = current times resistance, don't ask me why "E" is volts, but it stands for electromotive force). Then you hook the resistor up in series with the light and measure the voltage across the resistor (not across the light--LEDs don't act like a resistor like the old incandescents did). So, if you use a 47 ohm resistor and measure 4.47 volts, the current is 4.47/47=0.095 amps. (for LEDs, you need to initially use resistors in the range of 20-100 ohms. I have used higher values once I've determined the characteristics of the particular LED.)

You need a meter that measures current directly in order to find out what the LED current is at full brightness (that's without a resistor).

Zep

[Zeppelinium]

I made some diffusion lenses for the spotlights today. One was made of polysomething 0.050" thick and the other was acrylic 0.093 thick. I cut a circle to fit inside the front screw-on frame piece. I set the piece up on some wood blocks and used a heat gun on the plastic to allow it to sag into a dome shape. The poly sags pretty fast once it gets up to temperature. The acrylic, being thicker, takes some time to heat to a sagging temperature and I put a few bubbles in it. I think it's more susceptible to bubbles, but the thickness contributes to that.

You can see the poly lens sagged into a bigger dome and as a result makes a bigger diffused light pattern. The smaller dome of the acrylic lens didn't seem to affect the size of the inner/brighter circles much. The bubbles weren't visible in the projected light pattern. I think I like a dome about half way between these two. With a little more heat, plus some patience to avoid making bubbles, I think the acrylic can make for a bigger dome.







The "useable" light area means it's plenty good for walking around, finding things, and avoiding bumping into stuff.

Zep

[Keyair]

Gotta love ya Zep... you are the man!

[Zeppelinium]

Originally Posted by Zeppelinium

...The "useable" light area means it's plenty good for walking around, finding things, and avoiding bumping into stuff.

[ATTACH]177898[/ATTACH ]

I forgot two things. The pattern was made with the light 3' off the floor and tilted up and out about 45 degrees. If the light is up about head high on an awning arm or hanging on a window frame, the circles would be twice as big. In that case, the smaller dome is probably perfect, since you don't necessarily want a lot of light going horizontal out into space and doing no good. Duh.

You also have to sand the plastic dome with fine sand paper in order to get the diffusion. I only sanded the inside surface--you presumably could get more diffusion, but maybe less illumination, if you sanded the outside, too.

The polysomethingorother comes in about a 1' square at HD for $2. The acrylic is a rectangle with about twice as much area for $5.



Zep

[barts]

You can use air pressure to blow bubbles from polycarbonate. Take two matching pieces of ply, make a hole in one the side of the bubble base you want (doesn't need to be round) and make a matching fitting on the other piece to admit air. clamp thoroughly w/ lexan inbetween and heat; add air pressure to form bubble.

DIY Forming Lexan Canopies - Page 2 - Pelican Parts Technical BBS

Might make a nice change from those flat porthole windows
.
- Bart

[Zeppelinium]

I can take a hint. Turns out that Boyle beats Newton hands down when it comes to forming hot plastic!

I used the light bezel as an open die, with a piece of plywood with a hole in the middle (for the air) as the retention device. Worked great. This dome projects about 1/4", which means it's about 3/8" high (the bezel is fairly thick). I made a second dome that projects 7/16". There is only a slight difference in the diffusion pattern, but I like the higher dome for an area light.

Don't be too aggressive with the air. You will jump when the disc blows apart! On the other hand, I didn't have a real tight fit to the air, which allowed a fair amount of leakage flow--this helped prevent blowouts and also cooled the disc very quickly--it was stable in less than 30 seconds.







Zep

PS--thanks Bart.

[Zeppelinium]

I finally decided on how to hang the front spotlight. I made a narrow arm that is attached by using two of the screws that fasten the front window awning rail. The arm has a slot in it that the flange on the light's frame slips into. It sticks out to the side of the window so that when the awning is installed, the light is still able to illuminate under the awning. The arm provides the ground path, so only one wire is needed for the light. The power takeoff point is in the banana skin just to the right of door. (These spots are only installed when parked.)

These photos show how much illumination is available from the two spotlights and the over door light--the spots are on dim and door light is on bright. The total current draw is about 1 amp, including the marker lights. Note the the color of the step light--it's not that blue to the eye, but it is easy to see that it is definitely not a warm white.





It's a little unfair to assess the illumination level on the white snow--the bare ground doesn't glow that bright! However, the illumination level is quite bright even without the snow.

Zep