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Good Bye!

Thank you to all of you that took the time to read my blog over the course of the semester! I do not plan on updating it anymore since my class has ended. I hope you have learned as much as I have about these interesting subjects, have a great summer!

Peter Kelmartin


Gramophone Records and Players

Long before the introduction of mp3’s and CD’s most people used to play music through what are know as gramophone records, or just records. The most common of these records that were used from the 1950’s up to the early 1990’s was the Long-Playing record, known as the LP, which typically held an entire music album on it. Another popular form was known as the 45, which usually had two songs on it. The 78 was common before the 1950’s and usually had one song on each side, much like the 45.

So you may be wondering what all these numbers I am throwing around mean. It is the number of rotations per minute (rpm) that the record has while playing. For example, a 45 means it does 45 rpm’s while playing. Same for the 78. An LP does 33 and a third rotations per minute while playing.

These formats all use the same basic principle to make sound. A needle on a record player runs its way through the grooves of the record, which causes it to vibrate. These vibrations make the sounds that come out through the stereo.  Records can be made in monophonic, stereophonic, and quadraphonic sound. With stereo and quadraphonic sound, the needle plays both sides of the groove, so two tracks of recording can be played at the same time.

The White Album by The Beatles with white vinyl

The way records are made is pretty straight forward. Most of the time when recording was done in the 60’s and 70’s, the actual studio recording was done on a master track, which is a really high quality magnetic 8 track tape recording. Think of a very large cassette that is extremely high quality. After that is made, the recording’s that the engineer wants to use, are played back and a cutting needle spins around on a record and record the vibrations into it. A stamp is made of the record and then it is pressed into the vinyl records, which are distributed.

An LP playing “Good Times, Bad Times” by Led Zeppelin

Records are all analog sound. This means it is the original sound that was recorded. It is constant sound the entire time. A CD or mp3 is digital sound. The difference is that a CD is snapshots of the original analog sound, put together to make the original sound. This means that the digital signal does not capture the whole sound wave. A record is therefor a truer sound then listening to a mp3 or CD. Many audiophiles (including me) prefer listening to records for this reason. Studies have been done that show the brain receives much more stimulation when listening to a record over a digital source.


The main problem with records is that they are much more susceptible to scratches and wear. Playing the record itself wears out the groove. So the sound quality deteriorates over time, where as a mp3 will sound the same no matter how many times you play it.

I really like vinyl, I am planning on doing my presentation on it this Friday. I have a pretty large collection, I am listening to my vinyl copy of “Let it Bleed” by the Rolling Stones right now. I find it so much more enjoyable than just surfing through iTunes. If you are interested in finding records just go over to Squirrel Hill, and go to Jerry’s Records. It is one of the largest collections of vinyl in the country.


The USS Nautilus

The USS Nautilus is the world’s first operational nuclear-powered submarine. This was a huge accomplishment in the art of Naval warfare. The big deal about having a nuclear powered submarine is that it can stay submerged for a lot longer than a a diesel/electric powered submarines that were used in World War I and II.

To give you an idea of how much of a break through this was, I will tell you how submarines worked before nuclear power. The diesel/electric submarines of the the previous forty years ran on diesel power on the surface, and electric powered batteries when it was submerged. So a submarine could only be under water for a couple hours before it had to come up. Then the diesel engine would charge the batteries while it was cruising on the surface.

Then comes the Nautilus. It was authorized to be built in 1951 and the keel was laid on June 14th, 1952, and completed and launched on January 4th, 1954. The reactor was developed by Westinghouse after being asked by the government to make one in 1947. The Nautilus used a zero emission process that did not need to consume any air while running, which is crucial considering that a submarine is meant to run underwater.

The Nautilus is 28 feet long, and 28 feet wide. It has 13,400 horse power and can run at 23 knots at the surface, roughly 26 mph. It can fit 105 people on board for service.

The Nautilus was involved in a lot of firsts and records for submarines. For example it was the first submarine to complete a submerged trip to the North Pole. It also completed the the longest trip submerged underwater for the time, which was 1,300 miles. While submerged it could travel around 20 knots, which is about 23 mph. For the the North Pole trip the Nautilus traveled from California, up past Alaska and above Canada, then back down past Greenland. The biggest challenge faced in this journey is when it when through the Bering Strait. In some places the ice went down so deep that there was not that much room between the ice and the sea bottom.

The Nautilus’ final voyage had her go from Connecticut to California in May 1979. She was decommissioned and struck from the Naval Vessel Register in March of 1980. The Nautilus is now in New London, Connecticut and used as a museum for anyone who wants to see it. A vessel that at one point was extremely top secret and nobody could see it unless you were in the Navy or Government, can be seen by anyone who is willing to pay the entrance fee.

The Nautilus is a great feat of engineering. It revolutionized how a submarine is made and works. The one downside of it was the vibrations it made. It was very easily detected by sonar, and if you have ever seen a submarine movie, that is not a good thing. Right now all of the Navy’s submarines are nuclear powered. All over the world this concept is used by different countries Navies for their submarines and ships. Even air craft carriers are nuclear powered.


Ford Model T

After a couple of weeks of civil engineering topics, I am ready to get back to some mechanical achievements. This week I have decided to discuss the Ford Model T automobile. The Model T was the first ever car to be mass produced. It was introduced in September are manufactured until October 1927.

For some background, the Model T was made by the Ford Motor Company of Detroit and is also known as the “Tin Lizzie”. The Ford MC was founded in 1903 by Henry Ford. Initially all cars were hand made, with companies only producing a few cars a day. This made cars very expensive and most middle class Americans could not afford them.

Then comes the Model T. The reason for it’s naming was rather simple. There were nineteen models (models A-S) that Ford either tried to market or used as a prototype. The reason the Model T was so revolutionary is how it was made. Ford implemented an assembly line format to make the building of the cars more efficient and cheaper. In referring to the Model T, Henry Ford has this to say:

“I will build a car for the great multitude. It will be large enough for the family, but small enough for the individual to run and care for. It will be constructed of the best materials, by the best men to be hired, after the simplest designs that modern engineering can devise. But it will be so low in price that no man making a good salary will be unable to own one – and enjoy with his family the blessing of hours of pleasure in God’s great open spaces.”

It was Ford’s dream to make a car that anyone could afford. And he did that. The initial price was very steep, $850 in 1909 which calculates to around $21000 in today’s dollars, but by the 1920’s, the process has become more efficient and the volume of production had gotten so high that the price had fallen to $260, which is around $3,000 in today’s money. You cannot even get a decent used car for that now.

The first Model T left the Piquette Plant in Detroit, Michigan on September, 27th 1908. Initially a Model T took 12.5 hours to assemble, but Ford expanded in 1914 to include more man power and shorten production intervals so that it took only 93 minutes for one to be made and leave the production floor. At its peak production in 1925, between 9000 and 10000 were produced in a day. The Model T was so successful that Ford did purchase any advertising between 1917 and 1923. Henry Ford felt that the Model T was all the car anyone needed, all other companies could do was provide more luxury or comfort. When other companies began to offer the luxury and comfort at a more competitive price, Ford was forced to end the Model T’s production. It was replaced with the Model A which offered a more comfort for the driver.

The Model T revolutionized how the car was made. Ford got through the depression and is still around today thanks to the innovations and success of this early automobile.


The Hoover Dam

I enjoyed writing about the Panama Canal two weeks ago, so I thought this week I would write about another great feat of civil engineering. The Hoover Dam is a concrete arch-gravity dam in the Black Canyon of the Colorado River. This section of the Colorado is the border between Nevada, on the west, and Arizona, to the east. The construction took place during the Great Depression and lasted from 1931 to 1936.

The dam is 726.4 ft tall, 1,244 ft long, 45 ft wide at the top, and 660 ft at its base. The construction cost at the time was $49 million, which inflates to around $821 million in today’s money. Like most dams of this size, it is hydroelectric. This means it able to generate power by letting water through it and turn its turbines. It generates 4.2 billion kilowatts per year. This power goes to surrounding areas like Las Vegas and Southern California.

The damming of the Colorado created a reservoir on the upriver side of the dam. This created Lake Mead, which is used for recreation and water supply. Also, in 1948 a B-29 Superfortress crashed into the reservoir while on a test flight.

For construction, the Colorado River had to be diverted. This allowed the area the dam was to be built to be cleared, and the cement to be poured. Four tunnels were built, two on the Nevada side, and two on the Arizona side, to divert the river. After the river was diverted and construction could finally start, the first step was was to clear weathered rock in order to get to what is called “virgin rock”. Virgin rock is rock that is still completely solid and hasn’t been exposed to the elements yet. Weathered rock could allow for water to seep through and compromise the strength of the dam. The removal was achieved by workers tethered to the side of the canyon walls with jackhammers and dynamite. This was a slow, arduous, and dangerous process, not just for the workers on the wall, but those down below. Falling objects was the most common cause of death.

After all the bed rock was exposed, the concrete could finally be poured, which started in June of 1933. This was 18 months ahead of schedule. A total o 3,250,000 cubic yards was used in the dam before pouring ceased on May of 1935. Most of the work on the dam itself had been finished, and the dam was officially dedicated on  September 30th, 1935, by President Franklin D. Roosevelt. All that had to be done was the installation of the hydroelectric equipment.

The dam accomplished many things other than just stopping a river and generating electricity. The dam is the reason why Las Vegas is the bustling metropolis it is today. The workers would look to blow off steam after their shift and would go to Las Vegas. It kept growing after that. The project caused the death of 112 workers on the dam. An interesting, but sad story is that a surveyor was the first to die while working for on the dam, then 13 years to the day, his son who was a worker on the dam died while the dam was being constructed.


Job Shadow, not the post for this week.

Here is a part of my job shadow project about the company I worked for, W.L. Gore & Associates.

To give some background about the company, W.L. Gore & Associates was started by Bill and Vieve Gore in 1958. It was originally based in serving in electronics, but Bill’s son Bob Gore invented a new polymer that was very close to Teflon. This polymer is called expanded polytetrafluoroethylene, ePTFE for short. This discovery jump started Gore into the world of fluoropolymers, a field that the company is still committed to leading this day. Thanks to the invention of ePTFE, Gore’s products can be found in a myriad of different fields. A form of ePTFE is used in the new retractable roof at the Centre Court of Wimbledon. Gore’s most famous product is the water proofing in coats and shoes know as Gore-Tex.

This year, Gore was put on Fortune’s list of the U.S.s’ “100 Best Companies to Work For” for the 16th consecutive year. Gore uses a “Lattice System” to govern the company. This means it does not have a direct boss or chain of command, like most companies have. Each employee is given the title of “Associate”. Each associate is given a sponsor who evaluates his or her performance annually, with the help of the associate’s peers. It is this unique approach to running a company that makes Gore such a great place to work.

The Panama Canal

To switch things from space and rockets, I thought this topic was a little more down to Earth, but maybe even more challenging considering when it was made. The Panama Canal is a 48 mile long ship canal that runs through the country of Panama, and connects the Atlantic Ocean to the Pacific Ocean. This saved ships vast amounts of time. Before the canal was built, ships had to go all the way down past South America’s lowest point. Those waters are considered to be some of the most dangerous in the World.

Construction on the canal initially began in 1881 by the French. The French project went bankrupt, lost an estimated 22,000 lives, and spent $287,000,000. One of the main causes of all these deaths was disease. Malaria and Yellow Fever ran rampant through the workers. The project was abandoned in 1890 and laid dormant until 1904, when President Theodore Roosevelt decided that the United States to take on the project. Once the US took control of the project, it was done in 10 years. It was completed and opened on August 15th, 1914. This was also the same month that fighting in World War I began in Europe. The death toll was not nearly as high during the American construction, but still a significant amount, 5,600 workers lost their lives.

The canal is possible through a system of locks that bring ships from either side at sea level, to Gatun Lake, a made made lake created by a dam prior to the canals construction. The lake carries ships 15 miles of the 48 mile journey. Gatun Lake is 85 feet above sea level, which requires locks on either side to get a ship up to. On the Atlantic side, ships go through the Gatun Locks. This is a series of three locks that lift a ship up the 85 feet required to get to the lake. For those of you that do not know how a shipping lock works. It is a section of water that can be closed off on all sides. A ship from one body will enter the lock, the gates will close, water is either pumped in or out to bring the ship to the correct height of the water on the other side of the gates, and then the ship will exit and be in the other body of water.

The ship will then go through the lake and enter an man made river to the next set of locks. These locks will bring the ship back down to sea level, where the ship will be able to enter the Pacific Ocean, under much safer and shorter conditions than before.

Currently, the Panama Canal is being updated and expanded. It is approaching its 100th anniversary soon, and wear and tear is starting to show. A new set of locks is being looked at being installed on both sides. These locks would have Water Saving Basins, which means they would not need nearly as much water to get to the heights needed. This would also cut down on time.

The Panama Canal is an extreme feat of engineering. It is used by cruise ships all the time and even worked its way into cartoons.