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Flux Capacitor Lighting

Lights - How many are there?

Just how many lights are there under each of the fluxing tubes?  I just don't know. There are at least 4, but there may be as many as 6 from what I've read on other BTTF web sites.   While I'm sure having 3 would probably be fine, if I'm making the circuit from scratch, adding more lights is not a big deal.

Counting the lights in the flux capacitorI decided a little investigative work was in order.  I popped in my BTTF DVD and imported the Flux Capacitor clip into my video editing software.  It didn't take to long to find the right scene.  There is a key moment when Doc Brown points at the Flux Capacitor for a few seconds and explains to Marty, holding the camera how time travel works..

I captured the clip and looked at several consecutive frames showing the fluxing lights.  Now, I know all about film speeds and frame rates from 20+ years working for Kodak and there's just so much you can gather from looking at a DVD, frame by frame. 

 

 

I figured I'd count the lights I can see in each frame and plot their positions.

 Flux Capacitor Lights

Click on the picture above for a closer look.  I stepped through every frame I could and marked each light location that I saw.  Except for occasionally seeing two lights at once (one turning on and one turning off) I never saw more than the 4 positions I have circled.  Even considering frame rates and the possibility of missing a light, I'm not sure there are more than 4.

If you look at the spacing between the 3rd & 4th light (counting down from the top right) there may be enough room for another one.  Also the first three overlap a little but #4 is all by itself.

So, the jury may still be out for some, but I've settled on 4 lights.

Internal Mounting plate

Using several sources on the web, screen shots from the movie and trial and error moving some parts around on the base, I settled on the locations shown below for all the parts. Key to this was the placement of the LED's and corresponding Solenoid bases.  I labelled most of the holes below with the size drill bit i used.  In hind sight, and for my next one, I plan on drilling the 4 "arc" holes smaller than the 7/64 in. shown here.  That's just one of the many tweaks I'll be making on my next one.

Internal Mounting plate

Lights Bars

After I watched the video over and over, I've decided on 4 lights per fluxing tube.  I've spaced them out 16 mm, the first starting 8 mm from the back edge.  Yes, I know that's metric.  But it easier to measure than 41/64 of an inch.

After I watched the video over and over, I've decided on 4 lights per fluxing tube.  I've spaced them out 16 mm, the first starting 8 mm from the back edge.  Yes, I know that's metric.  But it easier to measure than 41/64 of an inch.

Flux Capacitor Light Bars marked

I use a mill vise on my drill press so that I can drill the holes in line easier.  First I drilled a 13/64 inch hole 3/8 inch deep.

Drilling the light bars 1

Then I counter-bored a 1/4 inch hole 1/8 inch deep.  This will allow the light bars to sit down flat over the LEDs.

Drilling the light bars 2

Here's what they look like after they were drilled.  They came out pretty good.

Light Bar drilled

I had to set it in place to see how it looked.  So far, so good.

testing light bar

Next I needed to sand and polish the top edge so that the lights will shine through.  This took quite a while.

sanding the light bars

You can see the progression of the sanding and polishing.  Acrylic is great because you can polish it to be crystal clear.

Sanding results

I then masked the edges and painted the sides a metallic gray.

painting the light bar

So, do all that for all three light bars and you can move on to the mounting plate.

Bright Lights - Big Problem

I've been experimenting with the Arduino and it is very fun to play with. I've been able to program a basic cascade pattern. I will post my code when I tweak it some more. I really like the flexibility it provides. Below is a video showing a quick test I did with the Arduino and a row of four LEDs. I set it to strobe at a constant speed.

You can see that the video also drops a few lights because of the frame rate (like the original movie).

The LEDs I'm using are very bright white. I ordered some Warm White LEDs and hope to get them in a few days. You can also see that I activate it using the RF Remote fob. The receiver is to the left at the end of the black cable.


Bright White LED's

I received my "Warm White" LED's today. While they were represented as a white LED with a yellowish incandescent glow, they sure look white to me. Below is a video for comparison. I also had the light sequence speed up each pass, to see what it would look like. I figured as the car approaches 88 MPH, the fluxing speed must increase unitl it reaches the magic number.


Yes, I know. I can't really see a difference either. Back to the drawing board. The good thing about dealing with a Flux Capacitor is it's pretty easy to go BACK and do it over. I really need to find an amber LED, I guess.


Warm White LED's


Another Experiment

Below I have added a second row of LEDs at an angle and also 4 additional LEDs that will be in the corners of the box. They are set to flash after the 88 MPH speed-up sequence.


I decided to go with the Warm White LED for now. I will continue to look for something closer to an incandescent look. The thing with LED technology lately is that every few months something new comes out and before long we should have something closer in color.