37 replies to this topic

[jc1991]

I've recently taken an interest in the concept of the Farnsworth Fusor (technically the Farnsworth-Hirsch Fusor) and the idea of building one.

For anyone who doesn't know what a fusor is:
It's a simple fusion (yes, that is fusion, not fission) reactor. They can be built for under $1000 in a basement if you go about obtaining the materials in the right way. (IE: Via Ebay and similar sources for the expensive parts.)

Basically the fusor consists of a steel (preferably) vacuum chamber, a high-voltage power supply, a source of deuterium gas (one reason the reactor is so easy to build), and two (or more) metal grids to help start the reaction.
The outer grid is left at its original voltage, and the inner grid is negatively charged. This causes the deuterium gas to become ionized, upon which it is immediately attracted to the inner grid. Because the grid has many large holes in it most of the ions miss it and collide with each other at the center of the reactor. This collision overcomes the natural repulsion between two like ions and causes the ions to fuse. The vacuum chamber contains everything and prevents dangerous radiation at low power levels. Higher levels require external shielding, generally via lead and/or water. Unfortunately, while the resulting reaction is spectacular to look at, it is of little to no use for producing power because the reaction does not break even with the amount of power required to cause fusion.

Anyway, is anyone else here interested in the idea? I'm currently laying out plans for construction, after which I'll have to get enough expendable money to purchase the materials.

Edited by jc1991, 25 November 2006 - 04:58 PM.

[caston]

I'm interested. Do you hope to improve on the design and develop one that can produce power or just make a fuseor for fun and games?

If you see my post on the fuzor.net forums you can see i've generated some debate.

http://www.fusor.net...&key=1164181348

There is a way to turn matter into energy we just haven't found it yet. Perhaps we need to somehow mimic the effect of anti-matter on matter without actualy going to the expense of producing it.

[jc1991]

At the moment, it's just for fun, but once the original is finished I'll probably begin experimenting in methods of boosting power output. It would be nice, but unlikely, to produce a design that breaks even.

As for duplicating the effect of antimatter on matter, interesting idea. I know next to nothing about cold fusion, but I'm always interested in experimenting.

[caston]

If you read one of the posts in that thread that I linked to says that cold fusion is now described as "compressed matter science" (CMS).

Being an IT guy I love the idea of using computers to simulate stuff. The big cell based heavy iron that IBM built for US DoE should be used to help us simulate fusion power. Perhaps we should talk about what software we would use to simulate fusion.

http://www.ornl.gov/...article05.shtml

The development of a home brew approach to fusion simulation is needed.

Have you ever considered a form of energy production based on the same principals as energy production in Mitochondria?

Edited by caston, 25 November 2006 - 04:26 PM.

[jc1991]

What, do you mean oxidation to produce ATP? Or am I misreading your post?

If that is what you mean, no, I've never thought about that. Based on my limited knowledge of the processes within Mitochondria, I suppose you could extract electrons and/or protons from the reaction. I have no idea how efficient that would be though.

[caston]

Yes, that is what I meant. I have no idea how efficent it would be either but I would love to find out. I think energy is protons and or neutrons.

[xanadu]

Very interesting. I would not want to make anything that is going to produce ionizing radiation because of the obvious danger. But, as a concept it is fascinating. I have a few questions for those of you who have looked into it more deeply. What does this part mean? "The outer grid is left at its original voltage, and the inner grid is negatively charged." What is the original voltage and is the inner grid negative towards the outer grid or in relation to some other electrode? What levels of voltage are we talking about and must it be DC? I would assume it must. Neon sign transformers can bring you up to 100kv or so, perhaps higher. How hard a vacuum must you have and how clean does it have to be inside? There will be contaminants coming from everywhere so it must be fairly tollerant towards that. A rectifier to change the high voltage ac to dc would be a challenge as well but I would think an appropriate vacuum tube might be the ticket. I just have no idea where they would be found.

[jc1991]

The original voltage of the outer grid is ground voltage. The inner grid is negative in relation to the outer grid. It's possible to use more electrodes, but it makes the design more complicated.

Voltage is variable, depending on the amount of output power you want. It should start at about -20,000 volts if you want visible fusion. Yes, DC is a must. (To my knowledge anyway.)

Deuterium gas will react violently with air, so a vacuum clean of air is needed. The contaminants from the actual equipment shouldn't effect the reaction unless you have some very unusual hardware. The vacuum should be pressurized at 10^-3 Torr.

I've always been recommended an X-ray transformer for AC to DC change.

Edited by jc1991, 25 November 2006 - 09:23 PM.

[xanadu]

jc, that clears up a few things but I have loads of other questions. What exactly makes the deuterium fuse? I read your explanation above but simply putting a charge on the deuterium ions does not seem like enough to bring this about. Other fusion experiments I've heard about used very much higher energies to make it happen. Banks of super high powered lasers were used to simultaneously slam into a pellet with the fuel. Your system sounds a lot like cold fusion that was discredited a while back. I'm not saying it doesn't work, I'm just wondering how a relatively low voltage of 20kv is going to do anything?

The original voltage of the outer grid is ground voltage. The inner grid is negative in relation to the outer grid.

If the inner grid is negative in relation to the outer, then the outer grid has a positive polarity. I can see how deuterium would react violently in contact with oxygen in the presence of high voltage. Where do you get your deuterium? If you have access to an old xray machine that should give you enough high voltage DC. If you don't, then the neon sign transformer along with a high voltage rectifier tube from a TV might do the job. A big enough TV might give you the high voltage DC all by itself but the available current will be low. How big a vacuum chamber do you use? Have you heard from people who did it and was their data convincing? You might be able to use glass for the chamber though I don't see how you get the vacuum and then inject the deuterium. That must be a good trick.

[xanadu]

On second thought, I may have figured out how they do it. Just flood the chamber with deuterium at normal pressures until you are sure it's all deuterium and then pump out your vacuum. That doesn't explain the fusion though.

[jc1991]

Your system sounds a lot like cold fusion that was discredited a while back.

Well, cold fusion hasn't actually been discredited yet, as no one can seem to prove or disprove it. Regardless, this is not cold fusion. It's very hot fusion. It simply uses much less power and generates much less power. As for a source of Deuterium, it can be easily obtained since it isn't a regulated substance and is non-radioactive.

The vacuum is established before the Deuterium gas enters it. If it wasn't, the tubes connecting the Deuterium source to the chamber would explode.

Fusion happens as follows:
The vacuum is established. Than the inner grid is charged to -20,000 volts on up. (Depending on how much power output you want.) After the charging process is finished, the Deuterium is introduced into the chamber. The high voltage charge violently pulls the Deuterium inward. Notice that the Deuterium itself does not recieve the charge. Because the grid is so thin (IE: It has large holes in it.) the Deuterium misses the grid and continues onward to the center of the vacuum chamber, where the particles meet and fuse. (It should be noted, Deuterium has a very high reaction rate.)

The Deuterium is introduced from a sealed chamber into a sealed tube connected to the vacuum chamber, to make sure that no air leaks in. The biggest problem is that once the fuel is used up, their isn't any way to reintroduce Deuterium without breaking the vacuum. (Or rather, doing so isn't easy.)

As for using glass, bad idea. The vacuum would implode the container, unless it was reinforced. Even then, the glass would become extremely hot once a plasma state was established. There would be a possibility of melting.

The process itself is old (IE: It was pioneered in the early 1930's by Philo Farnsworth. He also played a major role in creating the television.), and widely documented. Fusors are now widely (from the perspective of nuclear fusion technology) used as commercial neutron sources.

Edited by jc1991, 26 November 2006 - 12:18 AM.

[vortexentity]

I find the fusor work interesting but I have directed my attention to the hydrogen plasma vortex and light metals fusion technology. It is somewhat related but different in its construction. In the plasma vortex fusion device the suction head of the hydrogen plasma vortex is focused on an anode which is made from certain light elements that are easily brought to the point of fusion by the atomic hydrogen that collides with the anode material.

At the vortex suction head near the anode of the device the hydrogen's electrons are very near the proton which allows for a fusion with the light metals at a lower than expected energy. The metals used are B, Be, and Li. These are also the elements that for some reason do not follow the availability curve of elements. There is a dip at these elements so the theory goes that they are consumed and fuse into higher elements in plasma vortex formations in the universe like in the corona of stars and other vortex events such as in nebula.

Some very basic info is on plasmavortex.com

More info is here

From the Tornado and Ball Lightning to Controlled Nuclear Fusion

And here

Two component plasma vortex approach to fusion

and one more

Coherent electron catalyzed fusion

The experimental devices I have been involved with as explained in brief above are a bit different than these later abstracts detail but they use some of the same basic physics. The fusion technology I am interested takes advantage of a little known fact of these light metals in fusion reaction to atomic hydrogen.

See the below chart for details of the abundance curve.



Exploitation of this phenomena will bring about the fusion power that our planet needs.

Edited by vortexentity, 26 November 2006 - 12:59 AM.

[caston]

That makes a lot of sense. I know that lithium is used to breed tritium and boron-11 is used in focus fusion.

When you consider though that ITER (at least accoring to that ornl.gov link I posted) aims to basically use the heat from the fusion reation to boil water and then use the steam to move a turbine that maybe its no wonder that we have yet to get a net energy gain with an idea so primative.

Also maybe the "mean oxidation to produce ATP" by mitochondria may actually be very inefficent especially when we take into consideration all the fossil fuels and natural gas used to produce and transport food. Maybe in our quest to solve our energy problems we should consider modifications that could make the human body more efficient to run.

http://www.plasmavortex.com seems quite interesting. How did you find out about them and do you know anything more about the company?

This may or not be related but it is possible to produce hydrogen from water using metals like aluminium. I often wonder why they don't replace big noisy and smelly petrol/diesel generators with devices built according to this concept.

http://www.pinktenta...r-and-aluminum/

Edited by caston, 26 November 2006 - 01:58 PM.

[vortexentity]

caston,
The plasmavortex.com site is mine and so is the company. I am about to sign a deal to finance the prototype build for the demonstration unit. Our deal fell through with the inventor of the fusion energy device but we are not restricted in building a variation for demonstration of the plasma vortex. What is not shown in the model is the fine silver plated solenoid winding around the vortex chamber that is required to create the vortex effect. It was just too hard to 3D CAD model as the winding is very fine and thin. We actually will use a chemical reaction such as you suggest to obtain the hydrogen needed to charge the sealed units. we have tested them for ionizing radiation and it only outputs some UV light during operation and soft x-rays on startup. The units do produce some beta radiation if they use Li for fuel. The demo units will use Be,Mg,Al anode material which will not produce any Tritium.

We might make some larger ones set props for SciFi movies. Some Hollywood folks have shown an interest in having a bank of them as an engine core prop. It would be good exposure for the company and the product if we pull that off.

[xanadu]

jc wrote:

The vacuum is established before the Deuterium gas enters it. If it wasn't, the tubes connecting the Deuterium source to the chamber would explode.

Why would the deuterium explode? There should be no oxygen present at the time pumping begins.

Fusion happens as follows:
The vacuum is established. Than the inner grid is charged to -20,000 volts on up. (Depending on how much power output you want.) After the charging process is finished, the Deuterium is introduced into the chamber. The high voltage charge violently pulls the Deuterium inward. Notice that the Deuterium itself does not recieve the charge. Because the grid is so thin (IE: It has large holes in it.) the Deuterium misses the grid and continues onward to the center of the vacuum chamber, where the particles meet and fuse. (It should be noted, Deuterium has a very high reaction rate.)

What is it that accelerates the deuterium? Does the outer grid give a positive charge to the gas which then is drawn to the inner grid and flies through it to smash against other deuterium atoms coming from the other direction? What is the shape of your grids?

vortexentity, it's very interesting that you are involved in a company trying to start up fusion research. I think that's great. I take it you are accelerating hydrogen towards a fixed target. That seems more doable than trying to smash two particles together which would be hit or miss at best. I will check out your links and probably have more to say later on.

[jc1991]

Why would the deuterium explode? There should be no oxygen present at the time pumping begins.

I was referring to what would occur of there was still oxygen present in the system. I probably should have worded that better.

What is it that accelerates the deuterium? Does the outer grid give a positive charge to the gas which then is drawn to the inner grid and flies through it to smash against other deuterium atoms coming from the other direction?

Your summary is correct.

What is the shape of your grids?

The grids are spheres, one within the other, with Deuterium released into the area outside the grid. The Deuterium is always pulled into the center of the chamber, unless it is already inside the grids at which point it has enough acceleration to continue inward.

Edited by jc1991, 27 November 2006 - 12:28 AM.

[caston]

I'm very impressed. If there is anything at all I can do to help please let me know. I've finished uni for the year.

[xanadu]

jc, I can see that you would not want a lot of deuterium in the chamber when you turned on the juice because the atoms in the center which would be at rest would tend to get in the way. You want two ions coming from opposite directions to collide thereby giving you twice the velocity you could get from smashing them into a stationary target. That effectively doubles your voltage. Where the deuterium is injected from would seem to be important. If it's all put in at the same spot then the ions would accelerate towards the center but there would be nothing coming back to collide with. You would have to wait for them to go past that and hopefully make another trip in from the opposite direction. One problem with that is that the ions may simply imbed in the reactor wall or stay in that area. Since they were given a positive charge they would not be attracted to the positively charged outer grid and may stay on the outside.

Have you considered using a tube rather than a sphere? Using a tube shape with grids on both sides of center would allow you to shoot your ions toward the center from two directions rather than hoping they rebound. It would be like two guns shooting toward each other. You could use multiple grids each with a higher voltage to accelerate the ions even more. Accelerating them over a long tube should impart more energy than just the outer and inner grid. It would be a sort of particle accelerator using electric fields rather than magnetic fields.

[jc1991]

An interesting idea. I would have to construct or purchase some kind of firing device for the Deuterium, which would make the fusor much more complex. Adding grids would also increase complexity, although that's mostly a result of the fact that I would need more power to charge the grids with. There's also the problem of accuracy. The spherical electrodes make it much more likely that particles will meet and fuse. A cylinder would prevent any "missed" particles from fusing, as they would continue on to the end of the cylinder. The cost of reduced accuracy might overweight the gain from increased speed.

Either way, if I can get a hold of two firing devices of some sort, and a strong enough power source, I'll probably test a fusor based on a cylinder design.

Edit:
Another thing, which I'd entirely forgotten when I posted this. A fusor doesn't require complex magnetic containment of the plasma because it does the containing itself. The spherical nature of the entire system generates a soft of "natural" containment system that prevents the plasma from melting the grids or vacuum chamber. I have no idea if the same would apply in a cylinder. I would tend to think not though, based on my understanding of the principle behind plasma containment in the fusor.

[xanadu]

After considering the design a little more, I came to the conclusion that while some of the deuterium would fly past the outer electrode, most would be sent back and would recycle. If the steel containment vessel were grounded then the ions that hit it would lose their charge and could be picked up by the outer grid again and sent inward. It's a really simple but nifty design.

Your grids would have to be exactly spherical. They should be premade. Trying to bend them yourself with your hands is not going to be exact enough. You want both grids to be precisely focused on the center. A 1 mm radius focus area in the center might sound tight but you will get relatively few collisions. Making it a sphere with a radius of 10 microns would increace density and collisions by a million fold. Precision of construction and alignment will be key. Another problem is that almost all collisons will be at an angle rather than head on. It's your head on collisions at almost exactly 180 degrees that will give you the energy needed for fusion if it can be done.

A cylinder will be more complex and costly. If I were going to start with one or the other I'd do yours first. You could use one voltage source using a scheme like voltage dividers to provide various voltages to each grid on each side. Another way to do it would be to use high voltage transformers with a rectifier for each one. Those things are not expensive but the cost and complexity would be more. You would focus the beam with grids made of concentric circles. Further focusing could be with a circle grid of the same charge as the ions. By varying the voltage on that grid you would tend to constrict the flow of ions into a tight beam. The main advantage of the cylinder is that virtually all the collisions you get will be head on which is what you want. As for recycling the deuterium, the ions would tend to go past the point of collision if they don't collide and go to the opposite end. There, they could be recycled same as in the spherical design.

[knite]

could you just make a grid around the perimeter of the cylinder to bottle the deuterium into an incredibly narrow "virtual" cylinder?

[xanadu]

Let me say first that anyone thinking of making any sort of fusion device should keep in mind safety features. High voltage can be deadly so use the proper wire, insulators, and treat it with respect. I would strongly recommend a lead lined cabinet. It will protect you against explosions in case the deuterium ignites. It will also help block ionizing radiation all the way from soft x rays to high energy particles. Lead sheeting can be obtained cheaply and any sort of wood cabinet should do. I would also keep a fire extinguisher handy and do not run the device while you are away. Double check all connections, seals, etc before turning on power and keep close to the cut off switch in case anything goes wrong.

Knite wrote:

could you just make a grid around the perimeter of the cylinder to bottle the deuterium into an incredibly narrow "virtual" cylinder?

Yes, this relates to what I said in the last post about using a circle shaped electrode of the same charge as the deuterium to compress and focus the beam. This does not accelerate the ion beam but in fact will slow it slightly. You will need accelerating grids to give it momentum and use compressing grids sparingly to shape and focus your beam. I would seriously consider making a single accelerator first so that you can work on your technique. You could use a cylinder of pyrex or perhaps even plastic and a target of some material that will give off light when hit by radiation. This will allow you to see the size of your beam and you can play around with it until you get confident. It is still no toy and while you would not expect any fusion to take place, soft x rays and other hazards could exist.

[xanadu]

There are many other obstacles and hurdles to overcome. Creating and maintaining a vacuum would be top of the list. High end lab vacuum pumps cost tens of thousands of dollars on up. You will likely have to buy used equipment and compromise a little. Your reaction vessel will have to have a gasket that withstands a vacuum and you will need vacuum grease which is expensive. You might be able to scrape by with a high temp grease like lithium grease, not sure about that. You will need a port and a valve so you can pump the air out. Naturally it needs to be a special valve lubed with vacuum grease. The deuterium injection port is another subject. All objects put into the vessel must be able to withstand a vacuum without breaking down or releasing contaminants. That includes any wire, insulation, supports and welds or glues. You will need to drill feed throughs for your high voltage and need insulated fittings.

The safety cabinet needs to be large enough to hold all your equipment. If not, then your high voltage and vacuum lines will have to go through it creating more work. A window would be excellent. I suggest leaded safety glass with embedded alloy reinforcement wire or high strength fiber. If you can't find that you could get by with any leaded glass backed up with a piece of ordinary safety glass. This will allow you to look in and watch the progress in your glass or plexiglass accelerator. You may see interesting things going on and if you have a target, you can fine tune the beam to get what you want.

Is anyone still interested or have I managed to discourage everybody? jc1991, how are you doing? We haven't heard from you in a while. How will you measure the output from your reactor? You could use a geiger counter or cloud chamber to detect radiation. Or just measure the temerature. Make a number of runs without deuterium to see how hot it gets. Then run it with deuterium and see if it runs hotter and by how much.

I would flood the chamber first with deuterium and then pump rather than pump first and then inject deuterium. By pumping first you know that the traces of gas that remain will be 20% oxygen. By flooding first you can make sure the remains are less than 0.1% oxygen and other gases.

[jc1991]

I'm fine, just haven't had anything to comment on.

I have several options for testing the output. The best choice would be finding a neutron counter, but they tend to be expensive. ($2000 range.) The cheapest option is a bubble neutron dosimeter, which would run at about $100.


Unfortunetly, flooding the chamber first presents a real danger of damaging the grids in the resulting reaction.

As for cost overall, I intend to buy as much of my equipment from (reliable) second hand sources as possible. This will help to reduce cost quite a bit.

[xanadu]

Unfortunetly, flooding the chamber first presents a real danger of damaging the grids in the resulting reaction.

What reaction? There will be no oxygen present. That's the whole point. Doing it your way you pump first and then add De. Then you will have to pump again because you just ruined your vacuum. Doing it my way you pump once and get a cleaner mix.

I have several options for testing the output. The best choice would be finding a neutron counter, but they tend to be expensive. ($2000 range.) The cheapest option is a bubble neutron dosimeter, which would run at about $100.

I just saw several geiger counters and dosimeters on ebay ranging from $40 to $60. If you are trying to make the overall cost less than $1000 why spend $2k on a neutron counter?

What other uses are there for a particle accelerator or fusion device? It's a huge feather in the cap for anyone who did it. Taking photos to document your work would be a huge plus when people go out into the adult world looking for a job particularly if you are looking for something in the fields of engineering or research. Even if its unrelated to your eventual job area, it would be highly impressive. Just being able to tell people you own an accelerator or fusion reactor would raise a lot of eyebrows and perhaps gain respect and envy. Bragging that you belong to mensa is so 20th century anymore that few are impressed. A fusion reactor is something else again.

[jc1991]

What reaction? There will be no oxygen present. That's the whole point. Doing it your way you pump first and then add De. Then you will have to pump again because you just ruined your vacuum. Doing it my way you pump once and get a cleaner mix.

I must be misunderstanding you. The Deuterium is pure and pressurized to the level of pressure of the chamber. Once the vacuum is established, nothing but Deuterium enters the vacuum chamber. If you don't remove the air from the chamber before you introduce the deuterium, the resulting reaction is quite violent. Are you suggesting air removal, Deuterium introduction, and than vacuum? That would work just as well, but Deuterium gas comes highly pressurized, so you actually have to lower the pressure to use it in the fusor.


As for the neutron counter, I don't intend to purchase one unless I can get it cheaply or I get the funds from somewhere else. I intend to use a dosimeter, for the forseable future.

[xanadu]

If you don't remove the air from the chamber before you introduce the deuterium, the resulting reaction is quite violent.

De will not react with air unless ignition temperatures are present. It's just hydrogen gas after all.

Are you suggesting air removal, Deuterium introduction, and than vacuum?

No, that's your system. My system is put De in pushing out air and then pump. I can't explain it any more simply.

Once the vacuum is established, nothing but Deuterium enters the vacuum chamber.

You vacuum is never going to be complete. You will always have residual gas which in your case will be air. You then plan to put De in and as I explained, you then have to pump again to reestablish your vacuum. Do it however you wish and let us know how you made out.

[xanadu]

I was waiting for someone to suggest this but no one did. Maybe jc and I are the only ones still interested in the fusors and accelerators? If you want to save a lot of trouble, just use a bell jar and a base made for it. Bingo, no need to reinvent the wheel. You can pick them up on ebay for around $100 and sometimes less. You have your valve, chamber, etc all done. The high voltage will need some aditional work if the base doesn't have those fittings already but every thing else is done.

For making the sphere, it has to be precise and I have a suggestion about that. Buy a hollow sphere and cut it in half. You now have a form with which to fashion your grid and you will know it's symetrical. You can make half your grid, turn it over and make the other half or make each half separately and put them together. For the inner grid, get a smaller sphere. I've been trying to think of a source for ready made grids but don't know of any. You could use the hemishperical form and deposit metal inside it. Then, etch out what you don't need. Removing it from the form might be tricky but if you used plastic for the form you could heat it and evaporate it away from the finished grid or grid segments.

[jc1991]

I've actually been looking at using a bell jar. There might be problems at high power levels/high vacuum pressure, but I'm looking into that.

As for the grids, most current designs use multiple hoops made seperately and welded together. Your idea is interesting, although it would probably be more difficult to create the grids from a sphere. There are problems with the hoops as well, mostly with the inner grid which is smaller and thus much more harder to create.

[xanadu]

Using hoops allows you to have a symetrical shape but putting them together will be a problem. I was thinking to deposit metal on the inside of a sphere or hemisphere. You just spray or paint the conductant in a thin and even layer, connect an electrode and electrodeposit metal. You would want at least 20 or 30 mills and I'd shoot for perhaps 50. Then you have an even layer of metal in the shape of a sphere. Now, just draw your grid design with a special grease pen. Then, use acid to etch away everything except your design. Next, use solvents to remove the plastic mold. Or you could use wax even. Take a ball of the right size, coat with wax, harden and remove and you have your mold. Deposit metal and etch like I said. Use heat to melt away the wax. This gives you a precise exact shape for your grid. Do the same for the inner grid.

If you have trouble finding high voltage wire, spark plug wire should work. It should be good up to 30 or 40 kv. A little trick is to put flexible tubing over your wire to increace insulation. You can get it at any home improvement store. Get a size just larger than the wire so the wire will fit easily inside but not so large that the wire has lots of extra room. Another little trick is to get a piece of the next larger size tubing for a sleeve. Have a couple 2 or 3" pieces slid over the tubing with the wire inside. After you make your connections to the terminals, slide the sleeves down over the connections to insulate them. You have to put the sleeves on before you make your connections.

High power levels should be no problem. I doubt there will be a lot of current flow or power used. We are talking about accelerating particles in a thin gas almost a vacuum. Fusion power produced will be so small that you will need your geiger counter or dosimeter to prove there was fusion taking place. Make logs of the data you produce along with photos of equipment. It makes a nice scrap book. Science fair project anyone? Like I say, if you are looking for a job in engineering, design or a lot of related fields, having something like that to show the interviewer is going to put you at the top of the heap.