Project Euler - less than 1,000 people above me

Solved 267 problems, now having less than 1,000 people in the world above me out of ~925,000 registered members.

Affordable, iPhone-compatible prepaid MVNO plan with tethering included, finally

I used Verizon Wireless contract plan + phone for about 10 years. I started realizing that I didn't use as much service as I paid, because my primary usage was on data with very little talk and text. Also most of the data were through wifi at home and workplace. ~50$/month/line was not worth the money. I decided to go with prepaid plan. As I can buy a used unlocked cell phone if and when I need to upgrade. I wanted freedom.

So I switched first to Tracfone. Tracfone seemed to be one of the best MVNO (mobile virtual network operator; mobile service provider via borrowing physical network of major carriers) in terms of coverage, popularity, price, and customer service rating. The cheapest plan costs 20$ per three months for 180 minutes of call + 180 text + 180MB of data that rolls over to the next renewed period. Call + text allowances were more than what I needed. Data were not. I occasionally topped off with 1GB/10$ add-on package. Back then BYOP (bring your own phone) feature was a big reason to choose Tracfone as I could keep using my iPhone with the same number. (In 2015 most prepaid plans were available with highly limited range of phone models MVNOs offer. BYOP is almost an industry standard now.)

I was very happy with Tracfone for a few years except for a glitch covered in the previous post. The only major issue I had was the absence of tethering option. Which converts your phone into a mobile hotspot, so that any wifi-enabled device such as laptop can access the internet through the mobile data allowance of the cell phone. Tracfone does not allow tethering by policy. Probably because their parent network provider Verizon prohibits by contract, so that the privilege service is available only through Verizon? Most of the time I was okay since I didn't travel a lot. But there were definitely cases you really need and want it. So over the last years I kept searching for new prepaid plan with tethering embedded at an affordable rate. A few such plans as T-mobile prepaid were out there, but at a quite high monthly payment for me to seriously consider.

At last I found one recently - USmobile. They had all features I wanted. Choice of CDMA or GSM network, low price, BYOP, and tethering. I was highly excited so ordered a SIM card activation kit immediately and tested with a new number for a month by plugging in two SIM cards back and forth depending on usage (unfortunately iPhone does not support dual SIM). And the result was, YES, YES, tethering works. Not only that. From my limited test the coverage seemed to be wider than that of Tracfone. I used to receive cell phone signal in the area where I definitely didn't with Tracfone. Their pricing system is also more favorable at least two-fold. First, the customer has wider variety of choice of call / text / data selection with lower minimum. Second, USmobile offers bulk discount. For example 1GB of data for 10$, but 3GB for $20. Which Tracfone doesn't have. Why not switch. I would strongly recommend you to do the same as me. One minor downside is that USmobile doesn't have a dedicated mobile app unlike Tracfone. But I'd rather not care.

Once you order SIM card kit on USmobile webpage, it will be shipped out of Beaverton, OR. You might need to wait for a few days to receive it depending on where you are. The kit has both CDMA-compatible and GSM-compatible SIM cards. Their website seems to say that you need to use SuperLTE and purchase $10/month unlimited call / text + $15/5GB data plan to have tethering option enabled. But that is completely misleading. An official USmobile blog post published two years ago, saying that all Super LTE plans come with tethering included, is still valid. Overall, I paid ~4$ for SIM card + shipping, and pay <10$ for minimum of 40min call + 40 text + 40MB data per month. In addition, I would vote for USmobile on online chat service over Tracfone. I had to open a number of chat sessions with both carriers for the last couple of days to clear the USmobile SIM card (discarding the new number I used for the test) and port in the original number from Tracfone. USmobile agents were always quicker to respond and were more patient.

Why don't you give it a try like I did.

* Disclaimer - I do NOT receive any compensation from USmobile. I do NOT have any direct / indirect connection with them whatsoever at all either.

Road to certified Solidworks Expert - summary from parts / assembly design perspective

Looking back at the road I took toward certified Solidworks expert, I thought I should summarize what I went through, what each stage involves, and what they are for, for those who considering taking the steps.

First of all, I used Solidworks for a bit over 10 years. I would conservatively equate, however, it to 5 years of 'full time equivalent' professional experience. Also note that I mostly designed metallic solid models to be machined + bolted + welded in academic R&D environment. And it has been half to a year that I took exams below. I might have forgotten some detail, or have incorrect memory.

[1] Certified Solidworks Associate

The first step doesn't demand a lot. If you are familiar with basics of Solidworks, so that you can figure out what to do and execute it within decent amount of time even including a bit of web / tutorial search, then you could pass this exam with no big deal, without additional practice. For occupational solid model designer, 6-12 months of experience will do I believe.

[2] Certified Solidworks Professional

Considering that there is nothing much between professional and associate exams, step 2 is much harder than step 1; the exam deserves the name professional. You must be highly proficient with all major functionality of Solidworks. You will definitely need to actively study wide range of topics including those you may not need to use for your job. But not just that. You have to be able to apply features almost instantaneously with little time for mistake. At least in part I of the exam you are given a tight time margin, such that even if you execute all necessary steps in a correct and optimal way you will end up having spent 60-70% of the given time. Not a lot of time to think; you should be able to start modeling in a few minutes with a very complicated model, which can easily take 4~5 minutes just to have a firm understanding of the shape itself. Solidworks model mania can give you rough idea of the shape complexity in the professional exam part I. The rest of the exam, part II and III, are relatively easy.

[3] Certified Solidworks Professional Advanced

To spell out this section was the main reason I decide to write this article. There are 5 advanced subjects - sheet metal / mold making / weldments / drawing tools / surfacing. One needs to pass 4 of these 5 to qualify for certified expert exam.

The first four subjects cover special topics. They are certainly worth knowing, in the sense that building the same model otherwise will be badly inefficient, despite possible. But I would not call them fundamental since mastering those subjects don't really feed back to improve your parts design skills, with surfacing definitely an exception. Unless you specifically aim to take the expert exam, my recommendation is just a skim through the first four so that you can tell the time you need to practice them seriously.

One paramount example is the weldments. In short it is a sweep body where the path is a 3D sketch instead of 2D. You only need to provide a 3D skeleton sketch plus a cross-section profile with a bit of corner joining detail for a shelf frame for example. Modeling and modification is extremely handy in this scheme. Compare it with the case where one has to design each leg section and mate them one by one all manually. Sheet metal and mold are analogous. The same output, at a greatly reduced effort. Drawing tools is a bit different though. There are a number of useful features that show up only at this level of exam. If you need to handle a lot of drawing, I recommend you to learn the material up to the level required for this exam.

Surfacing is distinct from the other four. There are many amazing modeling techniques that are hardly accessible with solid-based approach. There are numerous features used only in the surfacing, as surfacing is built upon different design philosophy from solid modeling. In fact you just reached the other hemisphere of Solidworks. Only with surfacing you can have truly comprehensive understanding of how Solidworks operates behind the scene. In particular how the edges and faces at the solid surface are linked to the solid body, that forms the basis of being able to switch back and forth between surface and solid. Now you truly understand many cases which you didn't really care about until (or even after) you hit some error message. Now you get to know why Solidworks sometimes shows 'surface bodies' in the feature manager tree and how to properly tame them. When to copy feature or body for multiple instances. Etc, etc. Probably there are other CAD software better suited for surface-based design. Probably Solidworks itself is not the best software for such application. But I strongly recommend studying surfacing to those who seek authoritative command on Solidworks. Unlike the other four advanced topics, surfacing will greatly improve your design skill. You are now a true professional.

[4] Certified Solidworks Expert

In retrospect, expert level exam feels like a medal of achievement. Nice job done, but that's it. No more than that. Sure, there are still other dazzling things Solidworks can do. With expert certification you can describe and execute 99.9% of Solidworks features with confidence. But the techniques you add on top of professional + advanced topics I believe won't be as frequently used. You have mastered 99% of practical Solidworks with professional + surfacing. I would not strongly recommend the expert exam for the remaining 1%.