Engineering

I'm a student doing a research project on PCB's (printed circuit boards) for my Digital Manufacturing class. I will be discussing the current technology used today for constructing PCB's and the future developments of ink jetting circuitry. In regards to the first part of my project (today's method of making PCB's), I have been surfing the web all day to find a website that has a simple step-by-step procedure of how a PCB is built, but all the websites I have come across are so detailed and do not have a clear cut "list" of how a PCB is made. They all suggest different methods and I would like to know the general one that is used. I am aware of a copper clad on …

I`m in charge of several 2 stroke engines for agricultural use, once upon a time 2 stroke fuel was available then we had to use 4-star fuel and add 2 stroke oil to it and mix. NOW! the 4-star fuel is no longer available in the UK and so in addition to adding 2 stroke oil, we have to buy Unleaded fuel and mix yet another compound with it! apparently with some cars this happens too, the cars that ran on 4-star fuel have to either add this new addative (like Redex) or get the engine converted. I`m wondering if I can convert these engines to run on Unleaded alone without all the faffing about like an A` Lev chem exam! I don`t mind adding the 2 stroke oil, but wit…

This is a pretty cool site... I decided to register and ask my very first question.... I am developing an Excel Spreadsheet tool for learning purposes which demonstrates effects on power generation of automobile engines by changing various specifications like charge temperature, rpm, bore, stroke, displacement, manifold pressure, volumetric efficency, etc. The part that I don't have figured out is the part I am least familiar with... combustion characteristics and burn time. I know that rate of change effects, mixture, temperature, pressure, etc effects burn time... but how. I would like to have a magical equation that takes in account mixtures (of Air, N2O, Meth…

http://informationweek.com/story/showArticle.jhtml?articleID=163104221 Here's Cornell's news release complete with lots of cool pictures: http://www.news.cornell.edu/stories/May05/selfrep.ws.html

Now that I have your attention... Out of utter curiosity, how many people here have built a hovercraft from scratch? P.S. Couldn't think of a thread title. If any mods want to, uh, rename it with something more... intelligent, feel free.

I want to pulse a set of 6 LEDs. It should be one led at a time, not all 6 together. There is a site that shows how to pulse a single LED, but how do I get to pulse 6 of them, actually even 4 will do. The LEDs will run off a 3.7V @ 1070 mA. I tried to think of a simple solution without messing things up as space is also a constraint, but I ain't getting nowhere.

I am trying to build a house with a minimum amount of money as possible, as time, money, loans are short . I am currently just putting in a foundation does anybody have any smart ideas on reducing the cost of building the frame work. eg. I was going to use blocks but labour for building them and plastering makes it quite expensive. I would still like the walls to be stong and look as if blocks were put their???????????????

Some drunk driver hit a phone pole running from the cops near my house and when they were repairing it, they replaced the stoplights. I asked the workers if I could have the old ones and they said sure. Now I have 2 stacks of 3 lights (red, yel, grn) and I can wire them up simple enough so they all come on. What I want to do it wire it so they alternate, something with a small timer that will just rotate which light is on. I was planning on getting a plug with a remote to turn it off an on. Any ideas?

Why can't we make motor engines based on water, it sure has hydrogen in it? it would be a lot cheaper than converting to electricity or hydrogen. Alternatively we may build some sort of electrolytic system in hydro engines to seperate the elements, then all you'd have to do is pour water in as fuel. Maybe someone's about to make a lot of money on hydrogen.

Do you think that Engineering is a good career choice.considering outsourcing and the decline of industry?Do you think it is a "good job" Also... I was wondering what skills I need to be an engineer.You see I am very curious and like to know how things work.I am very good at math and also at science.I love all types of science esp physics and math I can grasp concepts quite quickly and am very analytical. However I am not very hands-on or into tinkering.I still like to be practical though. My family doubts my ability to be an engineering student for three main reasons 1.I am not detail -oriented.2 I am not a hands on tinkerer.3 I am theoretical all true.However I ca…

Hello Everyone, I am a student from California State University East Bay (formally known as Cal State Hayward). My group members and I are currently conducting market research on spectroscopy as part of a course requirement in our entrepreneurship course. More specifically, we are studying the demand for infrared technology in institutions, pharmaceutical industries, and other research industries from a marketing point of view. We have created an online questionnaire in regards to the applicable uses of infrared technology. The questionnaire contains 17 short questions plus a comment section at the end for any additional information you may be able to provide. Th…

If Engineering is not the best place for this, OK, but there would be a lot of engineering problems to be solved in a colonization project on the Moon, or Mars. Wanna discuss it? Is there a source of fuel and water on either or both? Are those sources exploitable? Food? Perhaps subterranian greenhouses?

Ok, I'll preface this by saying I know almost nothing about electronics, except the bare minimum I'm picked up fro Physics 2 and working with various things at the user level. Anyhow, a bit of background: I'm going to be doing experiments soon involving electromyography, the detection of electrical impulses in muscles to tell when they're active. Specifically, I'll be working with snakes, on locomotion. Now, our current setup has direct wiring, in that the wires go from the snake to the little screw-down connector thingys (told you I was bad at electronics) to the amps, etc, which means the length of the wires constrains the motion of the animal. What I'm wonder…

I have a couple questions regarding parameter definitions. I would really appreciate the help. 1. In most of the transistor, I've noticed that most of them have the term "Junction to Free-Air Thermal Resistance" and "Junction to Case Thermal Resistance". I am confused about this matter, so I just want to ask, what is the definition of those terminologies. 2. Ripple!!!! All this while, I thought of ripple as a small oscillation due to a filter. Am I right? Thanks in advance.

I have been given the project of making a radar for detecting Narc Aircrafts. Any info words ideas about how to do this (please something usefull) most of these aircrafts are cessna like and dc-x like. Radars based on the doppler effect are not useful, and i need to make it the cheaper that i can. thank you.

I'm building an amplifying circuit on PCB using two 741 op-amps, both inverting, giving an overall gain of 10. My output signal though has spikes...I've tried decoupling the power supply and that doesn't make any improvement, is there anyway to get rid of the spike and get a steady output from the op-amp circuit?

I plan to build a miniature wind tunnel, a lot like the Wright Brothers' used in 1901. I have stabilization (of model and air currents) all set up, I just have one problem- I have no devices to measure lift or drag. The site I went to (don't have a link, but if you just google up "wright brothers wind tunnel" you'll find it) mentioned that they used old hack saw blades and other things lying aroung to make their devices. My assumption was that they used a spring that was calibrated so that each increment would equal a notch on the hack saw blade. I want to look into making instruments that could do this or just find out what modern-day equivalents we have that will wo…

Can anyone recomend a good book or online resource to aid in making a model rocket? And if anyones actually made one is it hard and what sort of things will you need inc. tools etc. Thanks

I am learning how to make a PCB board using OrCad Capture CIS version 10.1. I've created the whole schematics for the circuit. The question is, what are the steps that is needed to make actually come up with PCB board layout? I will be greatful if someone can help me. Thanks in advance.

If you put wings on a car, would the lift make the car lighter and thus use less gas?

My dryer makes a very loud and continuous noise when the timer's up. How do I stop it? I'm no mechanic, but I want to stop the noise somehow.

I thank you for your time. I am new and I have been working on this problem for a while. Hopefully, I can explain it clearly. Motor I am using is a 12Vdc 1.7amp geared motor. Summery--I am trying to hook the motor up to a thermostat so that a window will be opened when tempature is above 80deg. And the window will be closed when the tempature is below 80 degrees. What I think I need to do: The thermostat can switch a relay on or off. So, use a relay and two limit switch on either side of the window, I should be able to have the window move one direction when the relay is on until it hit the limit switch. Then when the relay close it will move the wind…

Are there any glasses right now that can ignore the effects of mirages? Meaning if you wear these glasses, you won't see the mirage.

We are using 35% H2O2 for oxidizing spent caustic (strength between 1-10%, rich in sodium sulfide and sodium mercaptides, ranging between 200-20000ppmw). My concern is about using carbon steel vessel for mixing streams of caustic and H2O2 solutions, with recirculation pump ensuring 100% oxidation. How does the presence of H2O2 affect carbon steel equipment? Dillution rate of caustic is very big (max. allowable concentrations of sulfides and mercaptides before injecting H2O2 are 4500ppmw; vessel volume is 25m3), so unreacted H2O2 would be in very small concentrations. Oxidation is controled by H2O2 dozing and reaction temperature (<80C). If you have any suggestions,…

Does anyone know how artillery shells (Not fireworks) are made, The part i am most interested is the ignition cap. How do they make it.