Dr. Lasky’s Blog — All about Electronic Assembly Stuff
Dr. Lasky: a straight shooter, helping you keep your process performance on target.
Folks,
Folks,
Reader Chris and longtime blog friend Carl, pointed out that the "CE" Mark, that will likely be required for RoHS in the future, means "Conformité Européene". (Not Consultants Europe, as I said in a recent posting.) It appears that getting the CE mark can be done by a third party or a self declaration. My sense is that for a product like a laptop PC, it will require a considerable amount of analysis and paperwork.
Cheers,
Dr. Ron
Folks,
Every now and then a profound concept is developed that sometimes goes unnoticed. This past week may have witnessed one of them. PC Magazine's Cranky Geek John Dvorak announced the commoditization of the personal computer. Let me first defend commodities, before we think that his conclusion is too negative. Commodities are some of the most important items of civilization, what would we do without steel, wheat, concrete, polyethylene, gold and other vital commodities.
In Dvorak's article he discusses how PCs today have few differentiators, especially now that most are made in China. Without differentiators anything becomes a commodity. This trend has reduced advertising in magazines like PC and Computerworld hence, from a revenue perspective, forcing them to focus less on print media and more on digital media. Dvorak claims only Apple's innovation appears to keep interest in PCs high.
Dvorak thinks the future will be more tied to Smartphones, GPS, MEMS and other devices where opportunities for innovation are still strong.
I think we should not misinterpret John's article. The PC is profoundly important, just as steel is. Hundreds of millions of PCs per year will continue to be produced. There just isn't that much differentiation among PCs, hence its commoditization.
It is interesting that commoditization never happened to the automobile. There is still much difference between the 1995 Dodge Neon I retired last year and a Lamborghini!
Cheers,
Dr. Ron
WEEE RoHS
Folks,
Folks,
REACH (Registration, Evaluation, and Authorization of Chemicals) pre-registration ends today. If your company imports or manufactures more than 1 metric ton per year of any chemical, the chemical was supposed to be pre-registered by today. As I write this (1930hours EST) it is likely too late to pre-register as it is already December 1 in the EU.
While the EU expected about 30,000 chemicals to be pre-registered, I hear that over 1 million were. REACH's 849 pages (vs RoHS's 6 pages) make it the most ambitious law ever enacted by the EU.
It is expected that this law will take some time to unfold, stay tuned for updates.
Cheers,
Dr. Ron
Folks,
When I first started giving workshops on implementing lead-free assembly, I started to learn about WEEE/RoHS. At first, like many, I had trouble understanding why these laws were enacted, after all, no study showed that lead was leached into landfills from e-waste. Then I understood that RoHS was intended to make recycling easier. I marvel at how many industry leaders still don't seem to understand this point.
An article in National Geographic's January 2008 issue showed how much of our e-waste is being recycled in the 3rd world countries. The people performing the recycling are doing it in uncontrolled and unsafe conditions. This article was quite troubling.
Then along came CBS news with another article on the topic. This article called "Following The Trail Of Toxic E-Waste", was extremely unsettling, much of our e-waste is being smuggled into China and harming poor people who recycle it. The people have little alternative but to work under very toxic conditions. The worst area is a town called Guiyu. This article is must reading for those that think RoHS is a big blunder.
RoHS was developed to make recycling safer in the EU, in time as non-RoHS compliant products fade from the waste stream, it will help these poor people in towns like Guiyu to live safer lives.
The photo, courtesy of Custom Analytical Services is of a woman recycling in unsafe conditions.
Cheers,
Dr. Ron
Folks,
Folks,
I continue to get much interest in the solder alloy density calculator I developed some years ago. It is now online at http://www.indium.com/densityCalc/. It assumes no chemical interaction between the metals and no formation of interstitials. It works well for solder alloys.
Many people have an incorrect idea of how to perform this calculation. The most common incorrect concept is to multiply the % by weight of each alloy times its density and add them together . The correct derivation is below:
We want to find the density of an alloy composed of 3 metals. Assume the mass of the alloy is M. Metal A has a mass ma and a density da, Metal B has a mass mb and a density db and Metal C has a mass m c and a density dc. The total volume, V, of the 3 metals is va + vb+ vc, however since v = m/d, the total volume can be expressed:
1) V = ma/da + mb/db +mc/dc The density of the resulting alloy is D = M/V, hence 1/D = V/M, therefore:
2) 1/D = V/M = (ma/M)/da + (mb/M)/db +(mc/M)/dc
Now ma/M is the mass fraction of a, which we will call Xa, and similarly Xb and Xc for metals B and C.
Equation 2 then becomes:
1/D = Xa/da + Xb/db +Xc/dc which is our solution.
This principle can be applied to alloys of more than 3 metals.
Cheers,
Dr. Ron
Folks:
A while ago I posed the following as a typical type of question an SMTA Certified Process Engineer should be able to answer:
A 7 zone oven has a heated tunnel length (TL) of 250 cm. A 20 cm PCB (PCB Length =PL) needs to be in the heated part of the oven for 4 minutes. What is the maximum throughput (TP) in PCBs per minute that this oven can support?
The answer:
First we need to establish the belt speed, if the PCB needs to be in the 250 cm heated part of the oven for 4 minutes (t), the the belt speed BS = TL/t or 250 cm/4 minutes or 62.5 cm/min. So every minute the belt presents 62.5 cm new space for PCBs. So
TP = BS/PL = (62.5cm/min)/(20 cm/PCB) = 3.125 PCBs/ min, since a little spacing would be desired between PCBs, about 3 per minute is a practical maximum.
Golf Update: As I had mentioned early in the year, for the first time in many years I really worked on my golf game, playing about twice a week, and exercising and stretching. My typical scores were in the high 70s to low 80s, compared to mid to high 70s in my youth. Perhaps the most interesting thing is that with the modern clubs and balls I hit the ball about 30 to 50 yards father than when I was 20. I don't score as well because my shot game is not as good now (due to less practice I think).
As a result of this extra distance and interesting comparison can be made. From the time I was 10 years old until I was 60 (last year) a played about 1000 rounds, yet I scored only 4 eagles (2 under par on a hole). Form August 2007 through August 2008 I scored 3 eagles.........the difference? I reach many par 5s in two or drive a par 4 today, whereas when I was young it was a rare occurrence.
Cheers,
Dr. Ron
Folks,
The essense of WEEE is to one day approach 100% re-cycling of electronics. Around 2002 the world was at something like 10% re-cycling. With the high price of metals and the value of recycled components* re-cycling is not only the right thing to do, it is also cost effective. It is a critical part of "Sustainable Design," which many consider a new wave in the evolution of technology.
Therefore, one of the first questions to ask of a new technology is "does it easily support re-cycling." Thus easy dis-assembly is a requirement. So, when you see new electronics manufacturing technologies that make grand claims, check and see if it supports easy re-cycling.
The photo is from the January 2008 issue of National Geographic. It is easy to see from this photo why recycling is needed.
Cheers,
Dr. Ron
* Hopefully legitimate re-cycle components. Re-cycled components have a value to play in very inexpensive electronics and what pollution they save the environment when these components don't have to be made "again". The point is that anyone buying recycled components should know that they are just that.
Want to read more? Browse the archive of past entries.
Solution:
Since removing black, white, red and orange jelly beans has the same effect, they must all be the same number, let's call it X. So the sum of the black, white, red and orange jelly beans is 4 X. When the green jelly beans are removed there are 24, which must be equal to 4 X, hence X equals 6. So the black, white, red and orange jelly beans each number 6 and the green jelly beans number 2 less, or 4. The total number of jelly beans is 4 x 6 +4 = 28.
Folks,
A jar is full of 5 colored jelly beans: black, white, red, orange and green. With all of the black jelly beans removed there are a total of 22 remaining in the jar. There are also 22 jelly beans remaining if all white, red and orange jelly beans are removed, with the other jelly beans left in the jar. When all of the green jelly beans are removed, there are 24 jelly beans in the jar. How many of each colored jelly beans are there?
Cheers,
Dr. Ron
PS: Thanks to Marilyn Vos Savant for the concept.
Quick notes of interest:
Folks,
I guess I have stirred up a hornet's nest. My article Repeal RoHS Movement Emerges in the September issue of SMT and has generated much interest. I have even been accused of being the only person in manufacturing that is "pro-lead free solder." Wow! I think the folks at Motorola that have manufactured 150 million cellular phones, that could not be assembled with leaded solder, must have hurt feelings. Truth is I don't think I am "pro-lead free solder," I believe that I am pro data driven decision making....the topic for a future posting.
These articles have also caused much discussion on IPC's TechNet and I'm told a few other places.
Anyway check these articles out. I respect those that disagree with my perspective and believe that only by sharing and learning can we progress.
Cheers,
Dr. Ron
"He is probably the most influential American you never heard of. The "Father of West Point," "Father of Technology in the United States" and the founder of Thayer Academy in his native Braintree, Mass., Sylvanus Thayer arguably left a greater mark on our country than half of our Presidents. Without him, there might not have been a Grant, Lee, Pershing, MacArthur, Eisenhower, Patton or many other great leaders. Most of the early significant engineering projects in our country were led by students of his, most notably the Panama Canal and George Goethals. One of the last things Thayer did in his long and productive life was to found and endow the Thayer School of Engineering at his Alma Mater, Dartmouth College."
See how it all converges on SMT and six-sigma at the SMT Magazine website.
SMT Magazine is a leader in delivering sound technical information regarding electronics assembly materials, processes, and technologies. For a list of many of my contributions to this magazine, please follow this link.
If you're interested in reading some of my publications, you can find many available here.
June 13, 2008
Orlando, Florida
August 17-21, 2008
Schaumburg, Illinois
September 24, 2008
This weblog is licensed under a Creative Commons License:
The opinions expressed here are the personal opinions of Dr. Ronald C. Lasky. Content published here is not read or approved by the Indium Corporation and does not necessarily represent the views and opinions of the company. In addition, they are not guaranteed to be correct, complete, or up-to-date. By using this blog site you understand that any information or advice is of a general nature and may not apply to your specific situation. It is the reader’s responsibility to confirm and verify all information prior to implementing any endeavors based on the information. This blog/website should not be used as a substitute for competent personal advice from a trusted professional.
