engineer/designer vs builder/laborer

[Pat Barry]

Dale, I think you are generalizing quite a bit based on one or two small engineering mistakes. Fact is without the engineer to design your dies you would have NOTHING TO MAKE and complain about.

[Pat Barry]

Tacoma Narrows bridge collapse of 1940

[PAUL FOWLER]

punch small hole first!

[Matt Meiser]

Tacoma Narrows bridge collapse of 1940

I don't think that had anything to do with miscommunication between the engineer and builder. I think the engineer was fully responsible there.

[alex grams]

Matt i believe you are correct. That fault was just due to not accounting properly for the winds that came through the valley.

The only causality was fortunately a dog in the car.

[steven c newman]

Just a little story: It seems that a large city had just installed a new water treatment plant. All computer controled with just a few people to watch the dials. Opening Day came, the boss flipped the "Start" switch. NOTHING HAPPENED. An old-timer, who's job the new system replaced, spoke up.
"I can fix this,but it will cost you $10,009 " The frantic Boss agreed. The Ol-timer when to a valve, and tapped the side of the valve, system started right away. Boss: "You have fixed the system, but about the price?" Old-timer: "$9 is for the tap on the vavle, the ten Gs is for KNOWING where to tap."

[Tom Scott]

The OP asked about examples of designs that were not capable of being built in real life. A lot of the examples put out there did not fit that category, such as:
1. The Tacoma Narrows Bridge - It just so happened that the natural frequncy of the bridge almost exactly matched that of the wind coming through the narrows at a particular speed. When the wind reached that speed and the bridge started to vibrate, it kept amplifying until it tore itself apart.
2. The Hyatt Regency Bridge Collaps - This was a connection failure of a hanger rod. As originally detailed by the engineer, it would have worked. The problem occurred when the steel detailer changed the connection to make it easier to fabricate and install, and it was not caught in the shop drawings. It could have been installed the way originally detailed, but just not as easily.
3. The Office Tower in NY - This was a design issue. When the building was analyzed per the building code it with wind being applied normal (perpindicular) to the building faces, it worked just fine. This is how it was built. A grad student (in engineering) was doing a project analyzing this structure again, but this time applied the wind at different angles. His analysis showed the vertical braces to be over-stressed. He took it to the original designer, who verified his results and fessed up the appropriate parties. A logical fix was then designed and implimented. This case is often discussed in conjunction with engineering ethics.

I have been a structural engineer for over 20 years. Have I put things on drawings that were not buildable? Yep! As hard as I try, things slip by on occasion. There are a lot of details that go into designing a building. I work with a lot of design-oriented architects that have little savvy when it comes to constructability and what is possible. But, that is why they hire me. Their expertise is creating a building that evokes emotions that I never could...and I know that my job is helping them do that. They push my limits as an engineer and make my life interesting, and as result I push the limits of the contractors that build it. And because there has been a lot bashing of engineers thus far, I will say that it is not unusual for a fabricator or contractor to say something is not possible...until I tell them how it is possible.
The bottom line is that almost every project is a collaboration. Those that are successful have parties that know what they are doing, will work together and use each person's strengths. Yes, there are those young and inexperienced engineers/designers that don't have a clue as to how something goes together. They will either learn or they won't last long in the industry...the same as the person who can't learn to fabricate what is shown in the design drawings.

[Anthony Whitesell]

I know what you're after. I've encountered it many times. A person designs something on paper and then finds out it can't be machined or asseembled.

I once had a mechanical engineer design something that I could assemble. There was a 1/4-20 phillips head screw to be installed horizontally in a piece of electronic equipment in the bottom of a 4 inch deep slot 3/8" wide surrounded by steel. Ever try to keep a phillips screw on a screwdriver sideways? If a magentized screwdriver was used, it may wreck the electronics. We rolled the dice and tried any way, but it kept attracting to the side of the slot and knocking the screw off. We finally had to lay the 200 pound piece of equipment on its back to install the screw vertically. That way worked, first time. Just drop the screw in the slot, nudge to the hole, stand it up and screw it in. Still couldn't use the magnetic screwdriver.

I have no idea was the technical term is for something that is designed but can't be assembled, built, or manufacturer. Maybe we should ask Escher.

[John Coloccia]

I remember once my company designed a new configuration for a particular robot we built. This ran on tracks and was enclosed by a big box...essentially a large, fancy box sorter. Anyhow, we normally load the robot right on the the track from the back door....just slide it in.

We had designed one with a side door and they were assembling it on the manufacturing floor. I was working on some other project but was right near them and could hear them talking. The CEO comes walking through and stops at my project..."Hey, John...how's it going?"...blah blah...just some small talk. He goes to the new robot, takes one look and asks, "How are you going to get the robot in?". You see, it can't go in through the side door..it's got to slide in on the tracks.....LOL.

The solution was that you would just break it open in half, slide in the robot, and then seal it back up, but it was pretty funny.

[Ole Anderson]

Sigh... Engineers: its not easy being us, always the whipping boy. Everybody is an expert.

[Dan Hintz]

Ever try to keep a phillips screw on a screwdriver sideways?

They make screwdrivers with extensible wire prongs that keep the screw snugged against the driver's spurs for just such circumstances.

For future reference

[Michael W. Clark]

I've been a mechanical engineer for almost 15 years now and can definitely remember problems I encountered as a young engineer. It was tough with a steep learning curve and plenty of ridicule for mistakes. But, I kept trying to get better because I respected the ones building my designs and understood that if I could learn from them, I could produce better designs. Once I developed a relationship of respect with the fabricators, they had some respect for me as well (even taught me to weld). Not to say that I don't make mistakes and design things that are tricky or impossible to build, but once you have a collaborative relationship, you realize that each person brings ideas and experience to the table that makes the whole project better. This is true for most co-workers, but is especially evident in the engineer vs. builder relationship. I think too many young engineers don't respect the builders for their experience and see themselves as above them, unwilling to learn from the builder. In turn, the builders don't respect the engineers because they think they are inexperienced (which they are) and will not work with them.

Regarding the OP, paper may have already been written, but one example I thought of is the space shuttle that exploded. I think the engineers warned that the o-rings were too brittle and would not seal, but someone else decided to launch anyway? Please feel free to correct me if I'm wrong.

[Anthony Whitesell]

I think too many young engineers don't respect the builders for their experience and see themselves as above them, unwilling to learn from the builder. In turn, the builders don't respect the engineers because they think they are inexperienced (which they are) and will not work with them.

I'm not sure this applies to just young engineers. It may be more evident with them, but I also see it when an engineer new to the team has to work with the builder/fabricator that's been on the team. In the latter case, it's a matter of building trust. Letting the fab guys know that your willing to listen and work with them if they are willing to do the same. No stiff-arming. It can be a load of fun to work side-by-side with the fab guy, tweaking the design to get it built the best way possible in both the design and fab aspects.

I once had to choose some connectors for a new PCB. One was 3 tiers of 16 connections, another was 2x8, and the third 1x10. A total of 76 wires for the installers to connect. I had around a dozen choices and of them did care which was used. So I attended a manufacturing meeting with the shop guys and laid out the scenerio of the board, wires, and connectors and let them choose. They choose a spring loaded 2 piece design. This removed the torque requirement during assembly and allowed the connector to be attached to the wires without the board being present or installed. Looking back, I can see after that meeting I got a lot more respect from the shop guys when ever I went out to "pester" them with questions about something I was working on.

[John Coloccia]

Regarding the OP, paper may have already been written, but one example I thought of is the space shuttle that exploded. I think the engineers warned that the o-rings were too brittle and would not seal, but someone else decided to launch anyway? Please feel free to correct me if I'm wrong.

It was an entire culture of delusion.

For example, if you're riding in a car and 2 out of 5 lug nuts consistently come loose every trip, you would immediately recognize a dangerous situation. They're not designed to come loose...ever. NASA very much did the equivalent of saying, "Well, there are 3 other lug nuts. We have a safety margin of 60%!". They took signs of serious, but non-catostrophic, failure as a sign of safety.

[Matt McCormick]

problems between the person who designs and engineers thingswithout realizing what it will take to make their concept come true and thepeople who have to try to build that design.

Hi Curtis, Hope the paper goes well. For years I taught a machine shop courseto PHD students so they could work in the shop to construct projects. What agreat job that was,
Young men and women from all over the world.... all with differentpersonalities, goals and world outlooks. To get there they had to be the bestof the best. Some looked at me as a bum with a job, others looked at me as a wizard.Teaching how to run a lathe was easy...... teaching problem solvingharder........ teaching people skills ....real hard! but fun and rewarding. Ithink 90% of them walked away from my class able to work with the riff-rafflike me and get the job done..very well. That other 10%...well they have biggerproblems than a dumb old machinist.
My advice to them all when we finished up theclass was " when you have to work with machinist's.... Bring Donuts annnndtell them you are new and would like to get their advice on your project"I also tell them to go set at the machinist table at break time and just talkto them. The good engineers soon learn it isn't the donuts that have the magic,it is the personal respect that is the magic. I have gotten many phone callsfrom former students telling me how well this has worked for them and also totell me their new machinist is way smarter than the one they had in machineshop class! I laugh and then ask but can he eat 5 maple bars....... I lovethese phone calls. -matt