Bulding a Lightsaber (in 5 weeks) [June 2005]

First of all, building a Lightsaber was in my Project List but I never did expect to build it too soon. It all started when Kenneth, asked me to join him in building a Lightsaber for the upcoming Star Wars:Episode III premiere. However, we soon calculated that we have less than five weeks to do all this.

The Lightsaber Blade

After some lengthy brain-storming session, the best way to light up the Lightsaber blade was to use a very bright light source since using electroluminescent posed to be a very expensive problem. We really liked the idea of using EL because it is light. But the problem was, we would need to order it Internationally which takes time and also, in order to protect the lighting strip, we would have to search for tough polycarbonate tubes. We did try to ask aroudn but the guy keeps giving us the reply, "I'll have to check with the Factory". Using a bulb would be a nice and cheap option but because its lighting radiation was spread too wide, it would only light up the blade less than halfway up the tube. If the Lightsaber exists in real life, its weight lies in the hilt as the blade, since it is made of light, does not contribute to the total weight. So, it is easer to swing (How easy? Go swing your torchlight and you get the idea)

Since it was hard to get a polycarbonate tube with the right diameter, we opted for the next best choice; acrylic. Originally, we did go to a supplier who has, in their showroom, a solid acrylic blade with some fibre-optic core in the middle which lit up wonderfully. So, when you shine at one end, there is a straight 1cm beam of light all the way through. Imagine if you used a very bright lightsource. But unfortunately after waiting for three weeks, when he got the tube to us, it was the wrong one despite us describing to him what we wanted many times. Luckily, Kenneth was able to source the hollow acrylic tube in time, despite the price. As consolation, if we had gotten the solid acrylic tube, it would be too fragile and heavy to swing about. So, we decided not to deal with that guy anymore and not entertain his phone calls. We have stressed the urgency of our case but yet they treated us as if its just a normal enquiry. I will discuss with this in the later section.

This is the short demo version of the acrylic tube. The centre has some kind of fibre which lights up very well. The LED used here was a 1Watt Luxeon

When the man brought the acrylic tube we wanted, the core’s fibre was a spiral design instead of straight. So, the Lightsaber blade would as its made of dots. The LED used here was a 3Watt Luxeon

Luxeon LED

My idea of using the Luxeon LED came when we were at that showroom. Unfortunately, they were not able to sell it to us because it as a demo. So, after scouring the RS and Farnell catalogues, I finally made up my mind to get a 3Watt Cyan (Green) Luxeon LED along with the collimator lens. The 3Watt Luxeon produces about 80Lumens which makes it very bright. And very hot. It gets hot very quickly and therefore, in order to drive such an LED (you need about 1A of current) and still conserve power, I would have to design a Luxeon driver circuit. But because time was running out, there was no way I could get those IC chips in time and I would still need to test them. So, I made the decision to drive the LED directly from the batteries, using a 5 watt resistor to control the current. Not a very efficient use of battery power for this LED but then again, I am not going to turn it on for long periods of time.

By this time, Kenneth has decided to use multiple white LEDs to light up his Lightsaber. This was because his design allows him to separate his double bladed Lightsaber into two. If he had used Luxeon LEDs, the cost (about RM87 at that time) would be two-fold. But the results would be amazing.

The 3Watt Luxeon LED thatI had, comes with a star-shaped heatsink. Whenever an electronic components comes with a heatsink, you can be sure that it will be very hot. LEDs are current devices and with this Luxeon, it draws about close to 1A. So, I had a temperature test (using a PC temperature module) on the Luxeon. And the conclusion was, I really needed a very big heatsink, even though I am going to switch it on briefly.

The 3Watt Luxeon Star (right) and the Colimator lens (left)

The underside of the Luxeon LED is actually a heatsink which is the only part that is hot

This is how it looks like when the collimator lens is glued to the 3Watt Luxeon

Direct drive of the 3Watt Luxeon using a resistor. It is very bright and when I switched off all the lights, I can pretend I have a night vision. Ha ha ha ha

Testing the Luxeon temperature using a PC temperatue module

In l ess than 40 seconds, the temperature went up beyond the module's measuring range. The Luxeon’s own heatsink is not enough

The 3Watt Luxeon’s light radiation pattern without the collimator lens

The 3Watt Luxeon’s light radiation pattern with the collimator lens

 

Testing the 3Watt Luxeon on the acrylic blade.

The Hilt Design

The design on the hilt was loosely based on Qui-gon Jinn’s after I seeing Episode I. I was so in love with those flat discs (which are power cells in Star Wars) located on the hilt which also serves as part of the Lightsaber’s grip. But because the acrylic blade is going into the hilt, there is no way I could re-create them and still make the hilt strong. It would look beautiful if I could construct the the discs in such a way the acrylic blade will pass through them in the middle and a lit it from the end of the hilt, thus creating a glowing handle.

This is the handle and Control Box detail. Unfortunately, these are the only pictures I have left on my design plans and luckily I took pictues of them

Anyway, I happened to bump into a friend of mine by chance , who introduced me to a machinist. After a lengthy discussion, I had to redesign my Lightsaber. The reason was that I had chosen a 1.25-inch diameter (about 38mm) for the hilt, I have to take into account a lot of things. Firstly, the diameter must be large enough for the battery holder. And it must be narrow enough for the Luxeon LED and its lens to fit through. By the time hilt was hollowed out, I only had 20mm left in the middle to play with. The design for the discs (as handle) were gone, only to be replaced with bands of alternating thickness. Because I insisted on the bands, I have only about 1mm to play with the width of the internal tube. If he machined the inner grooves too deep, the hilt will weaken and break off. So, we sort of compromised due to the design and the material’s strength.

The Lightsaber’s outer copper layer (top) and its inner aluminium layer (middle). On the right, you can see the cover or rather, the bottom end of the Lightsaber. Slightly at the middle left, is the control box

The battery holder fits snugly into the whole hilt. But it is too thin to thread in the inner wall for the cap. So, in order to close up the Lightsaber, we hammered the cap in. Bad idea

To cut the design for the outer layer, it was not easy mainly because the copper tube was quite thin. And if he stuck it in the vice now, it would be bent out of shape. So, the machinist had to stuff it with some plastic material and cut it. If he had not done so, the tube would have collapsed halfway through.

After cutting the outer copper tube, we test fitted both tubes and they fit in quite nicely. The grooves you see on the aluminium was machined

Now, the hardest part. In order for the control box to fit into both tubes, a rectangular hole must be cut. This is also to allow the light from the Luxeon to shine into the Control Box’s acrylics. The machinist has started the cut (for the inner tube) for the Control Box
The he starts to make the threads for the screws For the heatsink core, the machinist milled out two small grooves
This allows the wire to go through the core and into the Luxeon LED without getting stuck inside Here, you see the heatsink core about to be test fit into the hilt. You can already see the Luxeon Star in there
This is the Control Box. The machinist built it using traditional way. In order to cut the smaller rectangular holes, he started with a hole and then using a thin saw, cut the shapes out. Note the straight line where the saw needs to go through to make every hole. If he stops and start for every hole, the machining time would have tripled and so was the cost. The machinist sub-contracted the making of the Control-Box so that he can concentrate on my inner hilt. When it came back, he just machined the curve underneath
I have taken out this switch in favour of the rounded button. This is because this switch is momentary i.e., when you press it, it switches on but once you let go, it switches off The completed Control Box. I have just added in the flashing LED and its bezel
Earlier, we had to test fit the Control Box again and again because this involves three layers of the hilt. If it goes wrong, then everything is wasted The three tubes fit like a glove. Once I attach them, only will I know if there is any problem in the design

The Lightsaber now consists of three tubes. The inner 10 cm bronze tube is used to grip the acrylic rod and also to keep the Luxeon in its place. Then the solid 20mm metal heatsink core (just behind the Luxeon LED) is screwed in its place from the second tube. The second tube, being made from aluminium, really holds everything together and also gives the Lightsaber its looks. The third outer tube, made from copper, is mostly for decoration.

This is how my Lightsaber looks like. Some of the parts have been made slightly transparent for better illustration. Missing were the three screws and the two holes at the front of the emitter. You can see the two tubes in the top half of the photo and how I used them to keep the electronics and the inner parts together. The cap at the other end of the Lightsaber is friction locked and until now, I still can’t open it up to replace the worn batteries. Ha ha ha ha ha

This image was done with Google’s amazing free 3D CAD software called SketchUp.

 

The Power box

Actually, its not a powerbox but just a metal block for decoration. This is the most expensive part of the Lightsaber as the machinist used traditional methods. At that time, neither of us have heard about laser-cutting. Otherwise, the cost would be much, much lower. Really.

I wanted the Control Box to have lights to shows its state or charge and so on. But after seeing another member’s design whose rectangular LEDs would move up and down ala Knight Rider, I decided to drop the idea. But I still wanted the lights. This posed another problem because to light up all these 10 LEDs, I would need a lot of power and not only that, if I put the electronics in there, there would not be any space left for the blade to enter. In the end, I cut pieces of acrylics, glued them in place and use the reflected Luxeon light to lit them up instead. This is why the hilt has a rectangular hole. The power Box also serves as the main component to lock all the three metal tubes together using two screws.

The third screw was to lock the Luxeon’s solid core into the hilt. Overall, I have designed the Lightsaber not to have any visible studs or screws that is out of place but to make it blend into the design so that it does not look out of place.

The Build

After obtaining all the components together, it was time to buildthe Lightsaber. With only less than 2 days to go, any mistake at this stage would be disastrous. Once everything was fitted together, I tested the Luxeon again as my fear is that the blade would be very hot within a very short time. And since everything in the hilt was made of metal, it effectively became a very big heatsink for the Luxeon. If it gets too hot, I would know. When I switched it on, even after more than a few minutes, the hilt did not heat up. The only heat I could detect were the ones from my hands on the hilt.

As for decorations, I decided not to pain the Lightsaber but rather show off its natural metallic sheen. But I wanted to cover up the aluminium hilt since it was so “bright”. I used darkened windscreen tints to cover it up. As for the raised edges, I used those 3mmx12mm black rubber foam. The outer copper layer proved to be a problem as it oxidizes quickly. After holding it for a while, your hands would have that metallic smell and the copper would have turned from shiny to blackish in colour. So I sanded the copper again and instead of rubbing the dust away, I use a clear gloss coat and mixed the copper dust into it to give a very aged look. In the end, I also clear coated the aluminium layer too. But somehow, maybe one day when I get bored with the design, I would remove the black foam and also the dark tints.

And with some copper dust mixed with the clear coat, you can see some subtle weathering.

I used dark tints, the ones you get from a car tinting shop and also black rubber foam. The foam is actually used for noise suppression but because of its rubbery grip, I decided to use it. At the time of the purchase, it was less than RM20 from Farnell Catalogue

This is the clear coat I bought at some DIY store in 1-Utama’s new wing. Can’t remember the price though. But now, its missing. If I did not use those tints and foam tapes, this is how my Lightsaber would have originally looked. Few details are missing but you get the idea

 

Final Construction

With everything put together, the Lightsaber looked quite decent. I won’t say its absolutely brilliant but its look as if it was found from some obscure cave having survived from a duel decades ago.

Test fitting the electronics before putting them into the Lightsaber permanently

Once the electronics are in, I tested the Lightsaber once again.
The acrylics in the Control Box were nicely lit by the Luxeon LED Note the flashing Blue led at the Control Box. Originally, it was a red flashing LED. You can buy these LEDs from Pasar Road and you do not need any other electronic components to make t flash. Just make sure you give it the correct voltage
This is how the Lightsaber looked at the final stage. There is one part which I was not satisfied, which is the activation switch. It is jutting out too long. It was also positioned there so that the battery holder does not move inside the tube and start banging on the the Luxeon’s heatsink And guess how much it weighed?
Yes, slightly more than ¾ of a Kilogram. Which makes it very heavy. But with the metal tubes, the lightsaber feels very solid and I have held a Master Replica Lightsaber, the weight compared, it is quite reasonable. For me, that is. Another shot of the Lightsaber. Oh well, at least the switch stops the Lightsaber from rolling about. I should go and buy a shorter switch. Sometime. Soon. Maybe this year
 
Here I am, at the Premiere, about to single-handedly destroy the Empire. This is the Art of Backstabbing at its best. Ha ha ha ha. 

Conclusion

Would I build a Lightsaber again? It depends. After the showing of Episode III, the whole Star Wars episode is complete. By now, you would have watched Clone Wars as well. So, the excitement has already started to die down, unless you’re waiting for the TV series. But anyway, would I build one again depends on the Lightsaber design and the available time I have. For you see, by now, almost every Star Wars fan has either a Toys ‘R’ Us or a Master Replica Lightsaber. For those who wants a real replica, there only so many Graflex handles in existence. So, it depends.

The fun comes in making a custom or unique Lightsaber. It does not matter if the Lightsaber works or is just for static display. After all, in a nutshell, it’s a fancy torchlight with a plastic tube stuck on it.

How the Lightsaber looks also depends on the power of your wallet and also the technology you are able get access to. For example, laser cutting is easily available in other countries but it is not easy to find them here. Moreover, if you did manage to find them you will have to expect three things and understand them:

But once you do get one, hold on to them because its not easy to find another. And its business as usual because you have to make sure their efforts are worthwhile too. So, if you’re really interested in making these items, its not only eBay that you have to go to. That is because, if you cannot get the items from eBay, you have to do them yourself. So you have to learn things like mould making, resin casting, silkscreening, etc. and again, they’re not easily available here. Your project therefore suffers a lot of delay. And that is only one part of the project you have to take into account. Now, let’s talk about the design.

The initial design would look good on paper but when it comes to actual reality, it could be very disappointing if you cannot accept any compromises. Over here, while making my Lightsaber, it has taught me a lot of things. It taught me how to go to the right person and how I must consistently network. It also taught me how to properly translate my design (from paper to reality) to a person who cannot visualize them. It also taught me how to be patient with them and to accept and understand their advise. And both of us have to learn from each other in order to get the job done. And there are things that I you cannot argue on how much it would cost to make because your design is unique and for prototypes, it is definitely an untouched area. Not only that, because my area is limited to electronics, I would also have to learn fast in terms of which material to use and a bit of mechanical stuff. Assumptions are not an option where millimeter measurements are concerned. But once everything is ready, you are the Master. You will assemble your design and when it is fully working, the feeling is undescribable.

However, once the euphoria has ended, I realised my Lightsaber looked very different from my initial sketch although it has retained some of the designs I wanted. And the cost to make it can easily be translated to two or three MR Lightsabers.

You know what? Sometimes its much better if you just participate more in Forums and scour eBay more often. But if you’re doing a really custom design, you’re usually on your own.

 

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