Universal AC Plug Model

Despite my company confidential project that I been doing, there is some component that modeled base on the data sheet. Well, some time they just throw me a component and the pain staking, measure with vernier caliper journey begin.

One of my favorite model is this Universal AC plug. This is special because there is NO data sheet been given and need to get the fine detail as close to the actual one as possible. Have a look…

Here is the actual picture, taken from supplier website:

Check down here for the supplier link:

http://www.wonpro.cc/en/products_list.php?catalog_id=44

You can download this and my other designed models via my 3D Content Central page. I am proud to be one of designer that contribute design at 3DCC for making SolidWorks… working world…a better place..

http://www.3dcontentcentral.com/Contributors.aspx?id=832104

And please leave a comment while you at it. Cheers.

SolidWorks related job interview tips

Let’s say, some day… that day may come (line from Don Vito Corleone, Godfather 1 movie ^^) you got call from a lady, usually a HR are or the receptionist, saying that you been invited to come to certain company for a job interview.

Ok, after you finished jumping and scream excitement to friend and neighbors,  there are things need to be prepare for this interview in order to guarantee it’s success.

For general things, head to this website Preparing for an Interview , courtesy lowyat.net. I will explain things that I did and hope this help in your future interviews.

1. Dress to impress – Long sleeve for fresh graduate and newbies, short sleeve are for pro. Depends on what job you interview, short sleeve showed that you are up to some elbow greasing rather than starring at a monitor all day.
2. Latest certificate first, school days later – This what I been suggested on my recent interview, the person said they are more likely to know what been doing recently rather than high school track record.For the school things, they would like to know you are active or not,rather than being a nerd.
3. Be a chatter box – don’t be a half duplex communication like walkie talkie. If they ask something, tell them more and try related to the things that you did, or cook something up. A general tips is, dont let the interviewer spend more time reading your certificate rather than your face.
4. Print out your design – “Print , or it never happened”, don’t just say that you did this, did that but nothing to prove.The interviewer are more interest in this rather than your colorful certificate and big number CGPA. To further prove that you made this, explain to them the step that you perform until you finished it.
5. Be prepare for the test – They wont just simply buy your story, high chance is they will throw something for you to design in a certain time on your first interview. When design against time, make you have an arsenal of shortcut keys memorize to speed up the design. Make sure you ask interviewer first, what version of solidworks been using in that company, so that you know the button location and work a round for a feature that  not been implemented on old version.
6. Ask when you will know the result – In generally, they would say 2 weeks. In truth is, if the company interest on you, they would call and tell the good news all call for a second interview. After one week, they is a higher chance they found some lucky bastard that better than you. This is base on my experienced.

For a bonus tip, it help to learn how to read body languages, this help to know whether a person buying what you said or you loosing them.You can google it a round, or go watch Lie To Me, a very interesting series, close to CSI.

So, good luck and may the force be with you.

Sketching like a butterfly,stinging like a bee

OK  OK, the title does not make sense anyway but I would like to share with you all some tips on sketching, the foundation of Solidwork modeling… well, other thing also…. so that you can make knock out punch of your design..anytime.

In sketching, there a two things need to understand and know where to apply; Dimensions and Relations.

First of all, the preparation  before sketching…

If you are new to  Solidwork and still learning it, hovering around and clicking icon in different place does not make  a big deal… but when you getting better, the urge to minimize such delay kicks in. That is why most designer use ‘shortcuts’ to sprint things up.

Depends on the user style…some like to organize their buttons on one side to minimize mouse movement  or while others like to right click the right mouse button to access the sketching buttons.

For me, as a gamer… prefer to dual-wield my input peripheral (mouse and keyboard) rather letting my right hand do the clicking and the lefty..well… touch some place the should not be mention here.

Since I’m used to FPS or RPG game key layout, the combination that I would like recommend to assign  as shortcut is:

(Tools –> Customize –> Keyboard)

Alt + S  = Smart Dimension

Alt + R = Add Relations

You be using this two a lot during sketching. Because in sketching, Dimensions and Relation is important, as I mention above

OK matey… lets start sketching.

The first thing you encounter when creating new part is to pick a plane as base. Before start anything, imagine the end product will look like and how it will stand, here is some guideline:

• Single thickness extrusion (chocolate bar,coin) = Sketch from TOP
• Cylindrical that need revolve (Tin can,bottle, vase) = Sketch from FRONT
• Model that need to mirror = Sketch from RIGHT (mean you need to model in one side, the final step is just to mirror to complete whole design)

Once you pick the plane, make sure to start at origin to avoid under define to your sketch later.

Press ‘S’ to pop out a sketch control button at you mouse tip rather dragging the mouse to the buttons at top screen. Exercise this method and you will cut sketching time a lot in the future.

I am lazy  to go through detail like how to use guideline to horizontal or vertical and read relation icon, I just point some detail that you might miss or dint know.

Lets continue…

Once you start dragging, notice the decimal number near cursor like above pictures? and it will change value according the distance or the way  you drag the mouse.Well, this number is a guideline on how the size it will be so that you would not end up sketching a M8 nut to a size of a 17″ inch wheel.

So next time don’t go happy-doodling like  it  was a Microsoft Paint. Pay attention to number , sketch respectively. (Do I sound like don’t drink and drive commercial?)

Once you finish your doodling… I call it doodling, because with out dimension….its just a concept, fresh from your brain…that Blue line need to turn bad to to Black.

The Blue line is under define,  a doodle. To give them attitude, you need to define them with relation or dimension.Once the turn black, any change will affect the other line if related to them. This how things been done hommies~

Hit Alt + S and start dimensioning from the maximum length (edge to edge)  and then after that,continue with inner side ad the doodle doodle line. Be aware on which to dimension first or you might end up with over-defined =  RED (If you keep ignore the YELLOW) at the end.

If you cannot figure out whats wrong and dunno how to fix it, allow Solidwork provide some solutions for you:

1. Hit the “Over Defined” button at the below screen
2. The Sketch Expert will pop out and offer options to solve the problem.
3. Pick “Diagnose” and browse through possible solution.
4. Remember, always pick option that have the least relation deleting step to avoid further problem.
5. All solution will solve the conflict but, only the best one will stay you out or trouble in the future..so,choose wisely.

But if thing get out of hands and your sketch have more yellow and red rather then black or blue lines… its time to wipe it all and start over again:

Display/Delete Relations –> Relations: [All in this Sketch]–> Hit “Delete All” button

Move your ass from your PC and take a walk and have a coffee break. Its frustrating at first but you get over it. The second time you do it, you already know what that to be done and what is to avoid. Dont finish the sketch of you are not happy with it.

OK lets move to Relation.

Relation is a bit tricky to manipulate and understand for beginner. For any line in sketch, you address it on what it will need to follow and posses relative  the origin. You can say it is a duplicate that you can control what to have from original or not .For me, I sometime I  use it to eliminate the need to dimension a same thing…I like my sketch to be neat and have only the necessary dimension.

For example:

Now the right circle have the same diameter as the left one with out putting dimension to it. For lines, you can assign it so that have a same parallel angle or been overlay on top of its original source.

Another thing need to understand about this blue doodle line is they tends to follow any fully define dragging them. It will come to nuisance sometime dealing with it.And by dragging the doodle line, if it move on certain direction..then you know where to put dimension so that it will lock in place.

Another good habit is to sketch or add relation base on construction line. You have a great direction once apply it properly.

Lastly, the ultimate way to define sketch is to use the “Fully Define Sketch” function. All the dimension and relation will apply relative to origin location.

Tools–> Dimensions–>Fully Define Sketch

Yes…it may save the  trouble from doing the manual step that I just explained…but bear in mind…use this in simple sketch… not in complex because you are not in a full control and if you do a major change like delete the existing line, at the end of the day, you might end up delete all the relation and sketch and start all over again. Use with extra, extra caution.

So, I bid you all farewell for now and happy sketching.

How Mechanical Design Engineer Work?

Lets see, if I got a kid right now, it will go something like this.

“Dad, what is your job?”.

“I’m a mechanical design engineer, sonny boy”

“Uh?”

See, its kinda hard to explain it. In lame definition its like you are rocket scientist to design that related to law of gravity, force, inertia which is not in my case.Well, that’s another kind of ME (Mechanical Engineer), but mine is man the keyboard and mouse all day long, thinking of something to craft from a thin air.

Think of me in situation that somebody sparked a new idea, and then you…which in this case is me, need it to be close to reality as possible.Be inspire, be creative…. Its kinda art actually.

The idea don’t have restriction, but when come putting  it together… the hard part begins.

To be honest with you all, Solidworks is easy to learn, and I really stress on that. The tricky part is to apply what you knew and implemented it at the right way and the right sequence and the right time.

“How you design actually?” If your kid ask.

The first thing is to gather information as much of possible rather then jump and open a new sketch. Dont just do it if somebody said that this thing need certaint length, width and height, you should need to know more detail…like is there any hole? Does the edge need to chamfer or not? What is the possible variable on design?

Make sure you have enough information to start a model foundation which in this case, the Sketch.

The best thing to do is to ask for the data sheet or technical drawing of the product that you need to model. Remember, if you cannot imagine the end product, don do it yet.Make sure you can visualize in your head first.

Next, model first, finishing later..

Don’t bother to put chamfer or fillet to the edge on a half done project. Later you might mistakenly following curve tangent rather then edge to outline another segment.The worse is when the chamfer/fillet is on the part that you need to delete later and it is related to others.

Another thing is need to know when to model using a ‘feature’ or just by ‘drawing’…

For instance, why you need to sketch a rounded edge rectangle when you can can just make ordinary rectangle and apply fillet feature later?  Another example is if you intend to put a screw hole, why draw a extrude cut hole when you can just use the hole wizard feature. You have more control of the thread size and end finish (counter sink or through hole) if want to modified later.

Try to utilize the feature provided in Solidworks, if the thing you making have a repeating profile= pattern it, if you think it have a symmetrical line = mirror it, don’t waste you time on sketch things that can be made using feature, it’s the foundation and keep simple and tidy…you don’t want to mess it around much.

Once you done with it, there is something need to consider = TOLERENCE.

In Solidwork virtual environment, all can be seen as match that has been made in heaven, when come to real thing.. nothings perfect. That’s why you need to leave a margin for error , and inform the toolmaker how much they can screw up. Normally, +/- 0.3mm should sufficient, so it should be that  gap between parts when parts mate in Solidworks assembly.

If you designing something that need to be injection molded, please bear in mind that its not everything can have 90 degree shoot straight towards the sky. All the profile that perpendicular to the product floor must have at least 0.5 degree of draft angle.

The reason is that injected material is shrinked down once it cool off in the mold.This will be inform by manufacturer how much shrinkage  percentage can happen. Draft angle can eliminate the problem that material stuck to the core or the cavity of the mold, and help the ejecting process by the ejecting pin. For more info can be read at here: http://www.dsm.com/en_US/html/dep/draftangle.htm

When to making assemblies, one rule of thumb needs to remember, DO NOT MAKE FUKIN BIG assembly!

You can actually assemble parts that is from an already made assembly file, making it a sub assembly. To much parts in one assembly will fryour workstation like playing Crysis game on a Pentium 2,if it can run.But “lightweight mode” can help if still want to do large assemblies.

The most important thing tips, MAKE SURE YOU KNOW YOUR WAY BACK.

Please don’t go happy extruding or digging hole on top of other thing when you can modify the original sketch. Later in a future when you need modified something; you have hard time dealing with invalid relation or over defined sketches, and that is the closest thing to hell for design engineer if you don’t know what you are doing. The may end up delete all the sketch relation or even worse.. make a new sketch.

Here is a tip; if you want know your way back, MAKE YOUR ROAD SHORTER. Try to eliminate the modeling step as much as possible, the tree that branches on your left screen. If you tend to make a long list of step, cut it back, later on it will save your time or life. In addition,don’t be lazy. Fully define the sketch… don’t over look the yellow warning, and for god sake, don’t  “Distance Mate” in your assembly just for fun, unless you are dumping the design to another guy that you hate.Please mate respectively.

So, there you are son… how to design and save your time and your ass in the same time.  Designing is a subject to changes, and you will never know when it will come, trust me….It happened to me a lot. This serve as a mental note to me and hope it will help you guys out there to understand more on Mechanical Design

Anyway, I attach my recent rejected by my management design due to their monkeys late to spark any idea over their brain since 2 weeks when I start doing this thing.Since it will not be implemented in final design, it safe to post it here.

It’s a lithium polymer cell pack for mobile telecommunication antenna base station all over Malaysia. This what happen when you substitute a monkey for a brain to decide which battery cell is FCC approve rather go the cheap one….sigh.

So, I’m signing of now… cheers to all.