Engineering on a mac? Answered

Can anyone recommend some CAD or CAE software for mac, I love mac dearly but i need some engineering software. 

Question by Douglerful   |  last reply


I was thinking that what will happen if we arrange inlet & exhaust valves on the piston (spark plug remaining on cylinder head)? i think that may be by using metal foam on the cylinder head the knocking of the engine might decrease. please assume that somehow i use proper mechanisms for valve timing & they dont have any appreciable effect on the piston. just consider that the weight of the valves is added to the piston. i was wondering that this might increase the efficiency of the engine because suction will take place more slowly (so it will near a reversible process, so efficiency will increase) & force of the explosion will be better. please you ppl; if anybody can give me satisfactorily explanatory answers, do reply! :)

Question by coepian   |  last reply

Is reverse engineering illegal?

Is reverse engineering illegal? Well, if you then go on to sell your version? For example, in an upcoming instructable I'm modding some electronics, well, without revealing my instructable here's an equivilent example: Lets say I buy a little robot at the store, it has motors and the case and everything. Only problem is, it runs on AA's and you want rechargable batteries. Also, the wireless module for some reason is external and is super ugly and annoying. You crack open everything and you find that the needlessly large circuitboards only have about 20 (somewhat) easy to find components that adds up to like 2 dollars. Following traces, you recreate a schematic from the PCB (already did this, that was fuuunnn :P). Now you reengineer the board (still same schematic) so that it's much more compact, you've added a little charging circuit (and correspond boost circuit, replacing a couple of AA's with a lithium ion), and you made it all fit inside the robot (no wireless module just hanging around outside the robot. Now, essentially the schematic is the same, but you've added stuff like the boost circuit and charging circuit. You've also added a few customizing features that make it more special (adding LEDs, microcontroller, cough cough etc.). Would it be illegal to sell a board/kit (incase other people want the board and can't solder smd to good) for people to modify there own robot (same model etc.). Also, the schematic from the reverse engineering is very similar to an example circuit in the main chip's datasheet, and a few other parts are common sense (like some resistors here and there, LEDs, a few extra filtering caps), so the company's circuit is nearly identical to the datasheet, is this illegal to sell?

Topic by guyfrom7up   |  last reply

search engine for instructables?

How come i cant find an instructables search engine that searches an instructables database?? I would certainly use this site alot more, as it is, I dont know If im going to resubscribe. C'on Instructables!!!!

Question by bestburglar   |  last reply

Turbine Jet engine...? Answered

If the intake turbines' speed is regulated by the compressed exhaust over the rear turbines, would it be more effecent to have 2 props in a row, or a single large one at the rear of the engine to control the rotation speed?

Question by shawneegeek   |  last reply

Electronic Engineering Project?

I am Student of Bachelor in Electronic Engineering in Final year starting, I want to select my Final Year Project and I have my passion in Robotics, can anyone please suggest me a great project.

Question by innocentkhalil   |  last reply

Electronic Engineering Project

I am Student of Bachelor in Electronic Engineering in Final year starting, I want to select my Final Year Project and I have my passion in Robotics, can anyone please suggest me a great project.

Topic by innocentkhalil   |  last reply

alcohol expansion engine?

While expirimenting in my back yard i came across somthing. I was working on my steam engine and was testing the boiler with methyl alcohol as the heat source( i used nitro car fuel 20%) and i wondered what would happen if i put the alcohol in the boiler. I heated the boiler at the same temperature as i normaly heat water and the alcohol seemed to produce alot more vapors at a faster rate and volume than just steam. So... I was wondering if it was possible to create an engine on the same basic design as a steam engine that ran on alcohol expansion. I do not realy plan on creating this i was just wondering if it would work as good or better than steam. If someone has already made this please tell me. Thanks

Question by myakka   |  last reply

Rocket engines, anyone?

 How can you make a simple rocket fuel with only materials that you could get from your local hardware store.

Question by 2tautges   |  last reply

V6 Stirling Engine

I have a 4.3l v6 that came out of a s-10 pickup.  I was wondering if i could make it run on the stirling cycle? It is a 90 degree v6 so it should work, This is the only site i could think of to post this question on. I was thinking i would isolate the water jackets to the right and left bank of cylinders then heat one side and cool the other. I am good with engines and am skilled in the garage. I'm just tinkering. Maybe run a generator with it if it runs. I have a welder, plasma cutter, ect and can use them. Just kinda throwin it out there...

Question by qparker   |  last reply

auotmotive engineering business?

Its awhile away but i want to know how to start my own automotive car business i love building things and making things work. sites would be best p.s. whats a good school (college) for taking an automotive class or classes

Question by DELETED_JAZ97   |  last reply

Search engine virus?

Occasionally, when I try to click a link to a web page (especially links that have already been clicked on and are purple,) I will be redirected to a different (and often generic/unrecognized,) website. I have had issues with this virus on a different computer and want to know if anybody knows anything about it. As in the other computer, when I am redirected, the small website identifier image (to the left of the URL,) changed to a sort of bluish 2 with kind of a flourish to it. A name to the virus would be helpful and a way to destroy it would be even more so.

Question by An Villain   |  last reply

project for mechanical engineering student? Answered

I am preparing a project on the topic "necessity is the mother of invention".i am a mechanical engineering student.can anybody give any ideas about what could be done on this topic. i am supposed to register the project unitl 12th plz u ppl hurry ?

Question by coepian   |  last reply

Any good books to read for getting started with mechanical engineering and electrical engineering?

Hello. I was hoping that you guys could give me some advice on good books to read. I am looking to get more into electrical and mechanical engineering. Any books that you would think would help me the most. I would be very great full for your guys help. Thanks

Question by cooldude01   |  last reply

Engineering Career Choice ??? Renewable Energy/ Electronic Answered

Hello I have a big choice with my career. I am not sure what to choose between electronic and renewable energy engineering. Could you please help me if you can. Thanks

Question by mechatr0nix   |  last reply

UG level chemical engineering projects (having some ICT relation as well)?

We are a group of 4 people. Must have some ICT (information and communication technology) relation. Should be cheap (in terms of cost). Not to complex for us to understand (as we are 1st semester students). Should be challenging (requires hard-work).

Question by Shirjeel001   |  last reply

Yanosuke Hirai

Here's another one of my occasional notes on Engineers  and engineering ethics. Yanosuke Hirai Hirai was responsible for insisting on the design of a sea wall which prevented another Japanese reactor being destroyed by the 2011 tsunami, and also for ensuring that, as the sea recedes sharply AFTER a tsunami, that the water intakes were placed so that cooling water could still be maintained.

Topic by steveastrouk   |  last reply

how can i design a rubber band pawered launcher?

This is a design project that i must do a rubber band powered launcher. the launcher must be able to reach a target 0f 2400mm from origin and it must be in the form of a vahecle

Question by rulph   |  last reply

How many resistors do I need to use for this configuration? Answered

I am soldering 5 standard Radioshack LEDs together to a 9v battery. How many resistors should I use and where? Should I go Battery-resistor-LED-Resistor-LED-Resistor-LED-Resistor-LED-Resistor-LED-Resistor-Battery? Or something else? Thanks. :)

Question by sciguy77   |  last reply

Help ! Auto CAD, Turbo CAD - What's best ??

I need a good CAD program. Have no experience in using CAD, but need something that will aid me in putting up a better wind charger tower (farmer, dependant on off grid power), need also to be able to design meshing gears and perhaps PC board layouts. The internet is so full of advice (read sales pitch) that I am frankly baffled. Come to think of it I also need the earth, but can't afford it. Need advice please

Topic by Karroo Oakey   |  last reply

I m currently doing my final year project in ME, i wanna ask abt what project can i do about centrifugal pump?

I m wondering what can i do about centrifugal pump, either its improving its design or doing experiment about it or do some research study about it ?  I seriously have no idea what can i do about it. but I just popped up with this topic in my mind, n I wanna do something about it. But i not sure what exact aim or purpose shud my project be, I need help in this..  Can anyone provide me with some guidance & suggestions ?  Ideas........ needed !  Thankx so so much if anyone is willing to help & able to help me ! Its very urgent actually. I need to submit my proposal n final year report in a short time. I wish i can finish it on time.  =)

Question by JesusLoveMe   |  last reply

>_< Specifications... i needz them.

So... about six months ago i moved into  new place.  it's great, but the previous tenants kinda trashed the place.  they left loads of rubbish around and were generally horrible to the house.  The previous tenants did leave a few things that are kinda nifty.  First, they left tons of PVC pipe. i have something like 20 ft of 2 inch pvc pipe, 15 ft of 3/4 inch pvc, and 10 or so feet of 1.25 inch pipe.  the second thing they left was an above ground water filter.  The owner's manual to the pump can be found here online: This got me to thinking i could setup a little hydroponic rig in my house. I have a hallway window which i'm too cheap to buy a blind for, and letting a bunch of plants cover it over appeals to me.  However, there's some problems.  The owners guide is critically lacking in any sort of technical specifications and all the info on the web just relates back to the pool pump being used as such.  Sooo... if anybody knows anything about what kind of performance can be expected out of this little dandy, let me know. 

Topic by Qcks   |  last reply

how to make a jet Engine?

Hi i wanna know how i can use nano tech to improve a jet engine?

Question by paymanf   |  last reply

A source for a small Diesel engine?

I'm doing a science fair project about algae biofuels, and was looking for a small, tabletop, less then 70 lb diesel engine. Oh, and cheap would be nice too :D.

Question by Rotten194   |  last reply



Question by bustedknuckles   |  last reply

Solar engine for a solar boat Answered

 Here of some of my queries.  we need to run a solar powered boat on a 1.4meter long water track in a shortest possible time( max time 5 min given)........ so i would be glad if u let me know the correct solar engine circuit to it..( i mean the capacitor selection , solar panel specifications etc etc) also there are many slar engine circuits online..which one do u prefer (1381,FLED,millers,zener based etc etc)           waiting for ur reply....... thanx in advance........

Question by abdul moiz   |  last reply

Electrical Enthusiast or Engineer Needed

Looking for someone that can help me design a system. This will include pcb layout and incorporation of wireless sensors or local wifi network and testing of the system. This is a great opportunity to be a part of great idea that will eventually be marketed, so it leaves room for great compensation. Anyone interested or that thinks they are qualified feel free to email me at for any clarification needed.

Topic by Island1337   |  last reply

Stirling engine displacer design? Answered

I am designing a gamma Stirling engine (this type) and I am unsure how long the piston should be and how long its stroke length should be the specs for the cylinder and piston pipes are below. The pipe for the cylinder is stainless steel. Wall thickness: 1.56mm Outer diameter: 31.7mm Inner diameter: 28.6 Length: 200mm (can be cut smaller) (Stainless steel cap will be welded to one end, the other end where the shaft comes out will be plugged with this nylon/graphite stuff) The pipe for the displacer piston is aluminium pipe.  Wall thickness: 1mm Outer diameter: 27.88mm Inner diameter: 25.88mm Length: ? (Two aluminium plugs will be used to seal its ends) How long should the piston, cylinder and stroke lengths be based on the specs?

Question by The MadScientist   |  last reply

Offensive Images on Search Engines

This is a Topic I've been wanting to discuss for a while, Offensive Images on Search EnginesYou've probably searched on google for a perfectly innocent image for something, only to get some what most will consider some very offensive images, mainly the male member (please stay classy on this, no comments I beg of you)This has really become an issue as these people insert popular keywords into these image sites so they will appear if one searches for something completely unrelated. This is truly a problem for moral people trying to go on with their regular lives.These cases have also moved out of search engines, as many of you will unfortunately remember hello.png ( I extremely warn you, DO NOT GOOGLE THIS! EXTREMELY OFFENSIVE> YOU HAVE BEEN WARNED NOW INSTRUCTABLES NOR I TAKE ANY RESPONSIBILITY FOR ANY RESULTS OF NOT FOLLOWING IT. )I would like to see your points of view in this topic

Topic by Keith-Kid   |  last reply

DIY water jet engine?

Hello. Me and couple of my local DIY buddies are also big fans of fishing. Because we are all students and can't drop 1K+ on normal outboard motor for our tiny aluminum boat, we are thinking on making our own. What we have here is a 200cc lawnmower engine. Because we don't wanna get into business of making our own gears we are looking for ways to implement water jet system. The problem is we just can't figure out what is gonna do a good job of being our turbine. Any suggestions? Does anyone know if the intake half of automotive turbocharger is gonna for pumping water?

Topic by Kizzmansky   |  last reply

Tin Can Turbine Engine

Hello!               Let me give you some insight into this project (Tin Can Turbine). I'm going to school to get an Airframe and Power Plant Cert. (Aircraft Mechanic). I stumbled across this idea on YouTube one day in class and it really got my gears turning. It's purely for fun, and I'm not even sure if I have the technical skills to get it to work.             First of all the way a turbine engine works in layman's terms is Suck, Squeeze, Bang, Blow. The fan section sucks air in from the atmosphere, Where it is moved to a compressor section which squeezes the air into a tighter pocket of air; which makes the air hotter and more explosive. When the compressed air is pushed into the combustion chamber, it is more volatile than normal air due to the compression. When you add a fuel (jet fuel, gasoline, propane, kerosene etc...) it will ignite with the compressed air (given that there is a spark to get the fuel vapors to ignite). When the fuel/air mixture is lit the fire will continue to burn without an ignition source due to the explosive nature of the compressed air. And the gas (burnt fuel/air) is pushed out the exhaust. There are blades in the rear of the engine called turbine blades, which are connected to the front of the fan/compressor section, in some cases there are two or three turbine blades, which drive the fan, compressor sections independently. Due to the turbine blades being pushed by the exiting gasses, the engine becomes self sustaining. And through black magic, you have a jet engine!!!              I'm going to attempt to construct a jet engine (not a motor!) out of a "tin can". I'm really not going to use a tin can, I'm actually going to use .032" thick 3" wide, and about 6" long exhaust piping made out galvanized steel. It's a lot thicker than a typical soup can, thus willing to stand up to more heat. My proposed fuel source will be propane, because it's cheap, and the I'm sure that I'm capable of controling the amount of fuel going into the engine. I'm not sure yet how many fan blades vs. turbine blades that I'm going to use. Right now I'm in the experiment phase. My blades are going to be made out steel can tops, because there is very little cutting involved, beside the actual cutting and angling the blades. and they fit perfectly into the pipe. As for the fuel delivery i'm going to use a copper pipe that is approx .042 thick and hallow. I'm going to cap the end, and wrap it around the inside of can. There will be eight holes drilled into the copper, which should give it plenty of fuel at equal pressure all the way around the can, equals same heat all around.         As for the drive shaft, I'm not exactly sure of what to use for that. I may want to go with something hardened already, so the heat surrounding it won't melt it. (that's the hope anyways) . I'm also not sure of what sort of bearings I will use. I was thinking skate board bearing with the plastic crap around the middle taken out (so it doesn't melt and seize the bearings) and extreme high temp. white lithium grease for lube.          This is an experiment and I guarantee myself absolutely no success. But I think it will be fun to try. Questions or comments are more than welcome. Please, if you see any problems with the design, let me KNOW!!!

Topic by shawnpc   |  last reply

Basic electrical engineering question Answered

Although I can carve my way through data and can tell you a lot about how data is stored on various mediums, I am not the best electrical engineer, but I still do some projects for fun. I have a project that I am working to help a friend of mine who works in a climbing wall.  They had an existing siren at the top for the kids that someone broke, and wanted to switch it out to something that they could put custom sound effects on.  I happened to think of the 9V recording module at Radio Shack (, and proceeded to hack it to make it more usable for their needs.  I made two different parts to it: 1.  The recording module in a project box, and 2.  A momentary switch at the top of the wall to trigger the module.  I changed the microphone on the recording module to a 1/8 in jack, sent the speaker output to a better speaker (with an amp of course), added a record button to the outside of the main project box, and created a "triggering system" by soldering a separate wire to both 1 and 2 in the picture, and then shorting it whenever I want to trigger the sound.  It worked perfectly in my shop, but when I installed it, the test trigger on the ground works, but the switch on top of the wall does not work well... it only works intermittently.  The wall is 2-stories high, so figure a 22 foot run for the wire (and I don't remember what gauge wire I used... it was just something I had laying around... but figure cheap speaker wire). My first guess was that it wasn't getting enough power from the battery, so I switched it out to a AC-DC adapter instead of the battery.  I am still having problems, so I am guessing it is too much resistance due to the long run?  (Would you agree or disagree?)  If so, is there some type of amplifying circuit that I could use to overcome this?  The only other explanation that I have is that the momentary switch that I am using at the top is pretty old and could be going bad, but I wanted to check first and see what you EEs out there think. Thanks for your help!  :) Edit: I'm sorry I am so bad at explaining this... I have uploaded my attempt at a schematic for clarification. Edit: After installing a new switch, it did work a little better, but still not 100%; so I installed the relay, which solved the problem.  Thanks to everyone who helped!  :)

Question by thegeeke   |  last reply

What's so hard about electrical engineering? Answered

I enjoy a lot playing with electronics and making new stuff, and I also understand electronics very good and am determined to do electrical engineering no matter how hard they say it is. I just don't understand what so hard about it, some people say it's the complex circuitry involved in it and some say that its the math in it.

Question by Wisaam   |  last reply

Jet Engine Question. Combustion in engine just used to expand air?

Lately I have been researching Jet engines. I once heard that the gas combution process was just there to expand the air being sucked in. Is this true?

Question by Kalrag   |  last reply

What is the best place to get low cost pcb boards?

I want to start with low quantities, I only need 2 layers, and all of my pcb boards will be relatively small. Most important, I'm on a pretty tight budget.

Question by sciguy77   |  last reply

Why did the duck go up? Any theories?;=related Skip ahead to 4:57. What he refers to as string appears to be an elastic material. He pulls up and it goes up. He pulls down and it goes up. The video is supposed to be about electrostatic toys.

Question by Vorenus   |  last reply

3D Modeling Program?

I have some ideas for a project I want to build, but I'd let to sketch it out in 3D form and create a model. Are there programs that can do this? I'd prefer free ones, but I guess I can shell out a few bucks if needed. I basically just need somewhere to put my thoughts into a 3D design so I can view what I'm actually building.

Topic by freethetech   |  last reply

What resistor(s) would I use for this LED?

What resistor(s) would I use for this ( UV LED? I'll be using 3 of them in a row with a 9v power supply, would I wire it to be battery - resistor - UV LED - resistor - UV LED - resistor - UV LED - battery? Or something like battery - resistor - UV LED - UV LED - UV LED - battery?Thanks!

Question by sciguy77   |  last reply

Confusion about transformers, specifically planar ones and how they work?

I'm trying to eliminate the need for a large coil transformer (120V, 60hz, AC to AC). Now I know very little about transformers but I've been researching planar transformers (for their low profile nature and weight savings) however they only seem to come in AC to DC variants. All of the reading I do about transformers state that all they do is change voltage through inductance. Why and how does a planar transformer change incoming AC to DC with out a separate rectifier?

Question by tofunater   |  last reply

physical and electrical engineering. what is a good thing to start with?

I am thinking about getting into amateur physical and electrical engineering. is there anything i can build, read, see or explore that would either spark an idea or get me some experience? (robotics, model-making, circuit boards) or even kits that you could suggest, involving that sort of thing. thanks

Question by shiboohi   |  last reply

Which engineering discipline is most worthwhile to major in? (mechatronics and nano included) Answered

 I am a student from Canada and I enjoy math physics and logic in general, some programs have a specialized 1st year so I'm wondering which discipline would be most useful in terms of enjoyment career options and pay.  So far I'm leaning towards Mechatronics at Waterloo and Mechanical at UBC and Queens (for those of you familiar with Canadian Universities) 

Question by ducktape1   |  last reply

What are some resources I can utilize to teach myself the basics of engineering and mechanics? Answered

Being adept in this kind of thing certainly gives one an edge in innovation by a wider range of what is physically possible to create. I am currently a high school student with no intention of earning a formal degree in mechanical engineering in the future, however, I do take a keen interest in it and would love to become knowledgeable enough to successfully, safely, integrate it into my inventions. I'm wondering how many of you actually have a background in this field and if not, how did you manage to teach yourself?

Question by orangejuicedisco   |  last reply

How do I get started in Electronic Circuit Engineering? Answered

I have been teaching my self the basics of Electronics in the past month and I think that I am far enough along that I want to start teaching my self what goes into a circuit.  I understand the fundamental stuff, the basic parts and pieces and now I am trying to find some books that explains a circuit.  Take for example a 2 transistor LED flasher. I can build this circuit from memory and is simple enough and you can find many diagrams of it on the web. What I cannot find is someplace that explains step by step the processes occurring that make it actually flash.  The above mentioned circuit is simple enough for me to understand what is going on, but I am not talking about that one circuit in particular. I guess what I am after is a guide that teaches me how to read what a circuit is doing, and for what purpose a component is needed for in a circuit. I hope I was clear in my question, I wasn't really sure exactly how to ask. 

Question by atrumblood   |  last reply

School course of study?

Hello everyone, I am not sure if this is the right place to post this or not, but I am looking into going back to school. I would like to be in an industry where I can learn how to make things like robots, and electric cars etc.. I am sure these things will require more then just a basic degree but I would like to get started in the right path. The problem I have is, would these fall under mechanical engineering or would if be electrical engineering? I like the idea of building something from concept to final design where I learn the hardware as well as the programming skills to make the device do what I want it to do. So can someone tell me what course of study would be best? Thanks, Jester

Topic by Jester_boy2   |  last reply

Ceiling Fan for a Theatrical Production?

My theater group is doing Guys and Dolls for our spring production, and our director wants to have ceiling fans in a few of the scenes. Is there any way to create prop fans that can hang from a fly rail and rotate, but without being electrically powered? Thanks in advance!

Question by earningmyimaginears   |  last reply

Can I have a quick hand putting this simple circuit together?

I've begun to try to put together this circuit myself. I have all the parts, but I'm horrible at reading schemas. I've failed 4 times now, and only managed to get a little movement from the motor once. I've read a couple tutorials on reading schemas, so I know most of the symbols, but actually putting them together is a whole new deal for me. I'm trying to get a photo cell to regulate the power of a motor without starving it of power. Could someone please give me a bit of direction as to how I solder the parts together (i.e. solder resistor to the left lead of the transistor etc.)? Thank you for the help. :)

Question by sciguy77   |  last reply

Any one here have an idea as to the wiring diagram of a Astec AA20540 computer power supply?

Here's the problem. I took the 20pin header off an old ATX motherboard thinking I could just match the wire colors and presto, a working PSU. Unfortunately the before mentioned unit doesn't seem to have the same color codes for the voltages and/or standby power/wake wires. See I do know a little about them. Normally the green wire, when grounded turns the unit on. Not the case with this one. It's plenty frustrating I can assure you. I don't exactly want to go just randomly shorting out different wires to find the right one either. I want it to work when I'm done. Help, I've looked everywhere else.....

Question by Koil_01   |  last reply

need help with joining 6 speakers

Hi~ I currently need help in knowing how to attach 4 speakers and 2 subwoofer together while making sure it's portable. It also needs a mic jack plus a plug to be able to plug to a mp3 player or a smart phone. I think it needs to be powered by batteries as well? It's for a cosplay costume i am doing that have speaker attached to it and since the costume will have my mouth covered by a mask, i decided i could actually make good use of the speakers to talk to people with a small mic hidden under the mask. But the thing is that i have totally no idea on how to do it, i have found some tutorials but it doesn't seem to match what i am planning to do. It would be nice if anyone is kind enough to help me with this problem. Thanks :) Here is the image of the cosplay i'm planning to do:

Topic by sakura_rin   |  last reply

what drives the compressor in a jet engine? Answered

Does a motor or something drive the compressor in a jet engine.

Question by Tawhid K   |  last reply

How to make a "Preferance" Search Engine.?

Is there something to make a search engine with? Where people can put in what they want, like >50 in, and the products shown will all be greater than 50?

Question by Batryn   |  last reply