I bought a DR Power Wagon a few years ago -- an expensive piece of gas-powered yard equipment with a spring-loaded throttle grip. When I uncrated the wagon and started it up, the engine immediately raced. The centrifugal clutch engaged, and the thing took off. Fortunately, I was able to grab the brake and stop it safely.
It took all of 45 seconds to find the culprit. Where the throttle cable attaches to the carburetor, there is a return spring on a bracket. The bracket is held to the engine by one screw. If this screw comes loose, the spring tension rotates the bracket until the spring is loose. Voilà: no throttle return spring tension.
The fix was easy. It took longer to find the right wrench than it did to rotate the bracket into position and tighten the screw.
So, a simple quality issue, right? The screw was left loose, or it came loose in shipping. In my industry (automotive), we would never leave something as critical as a throttle spring with such an easy failure mode. The bracket needs two screws so it can’t rotate, or a notch or tab or something, even a self-locking fastener. Or the design engineers could have put the spring someplace where the support can’t come loose. There are a number of easy ways to solve the problem.
This entry was submitted by Erik Kauppi and edited by Rob Spiegel.
Tell us your experiences with Monkey-designed products. Send stories to Rob Spiegel for Made by Monkeys.
While I truly appreciate your efforts on consumers' behalfs by instilling in your students the problems of poor and/or ineffective design, I'm convinced that your efforts will for the most part will go unapplied.
When these students become wage earners, they'll be required to answer to a "higher" authority, that being the "bean counters" of their employer. So, while all your "preaching" may have instilled in them a personal ethical (moral) code, it will undoubtedly only be exercised in earnest on their own property when they're mowing their lawns, painting their houses, running a new circuit for a recently acquired appliance, etal. In other words, their own personal work will be done precisely and with due diligence in respect of local codes & sound engineering.
As an optimist, I HOPE for the best in design; as a realist, I know the results will be influenced otherwise!
Send more if you think of any. Also, we're always on the look out for Sherlock Ohms submissions. If you have worked your way through a tricky engineering problem, we'd love to hear about it.
Yeah, they could have done it any of the ways you mentioned and it would have been safe, but I bet they saved 5 cents by doing it dangerously. That's how cheap everything has become. Save 5 cents even if it's unsafe. Makes no sense, just one huge lawsuit ruins that profit margin.
I have had a DR tow--behind mower for several years. For the most part it has some clever design features; like a triangular piece in front of each wheel so that if you get too clse to a tree or post it will not take off the wheel. It also has the ability to offset the mower from the tow machine so that you can mow to the side of the track of the tow vehicle. However, I had a problem after a few years that it all of a sudden started leaving an unmowed strip behind it. I called customer service and even sent them some pictures of an area that I had just mowed to show them exactly what I was talking about. They had no idea of what could be causing the problem and made a few suggestions which had no affect when I tried them. It was that way until just recently when I noticed that the blades were not attached correctly. After correcting that it has worked much better, but does not cut evenly in heavy brush. Certainly like they show in the TV ads. Another problem that I had was with the operation of the throttle. After several years the only way it would run was with the throtle in the choke position. Again, I contacted Customer Service and they were of no help. Also, again, I sent them pictures to fully describe the situation. The few suggestions that they made were not only of no use, but really did not address the situation. Finally I took it to a local repair shop (who normally will not aork on DR equipment, but did for me as I am a steady customer). After him having many more discussions with DR and not getting any useful information, he finally solved the problem by adapting a part from another model Briggs and Stratton engine to this engine, like it should have been in the first place.
One feature that I feel is poor design is that the hitch only allows movement in the horizontal plane, but not in the verticle plane. This is fine if all you mow is fflat land, but can cause problems if mowing on uneven ground. I would think that a standard ball hitch would be adequate, or some other design that allowed free movement in both directions.
I know this is not all exactly "Made by Monkeys", but it certainly "Sold and Serviced by Monkeys". Other than these, and a few other minor problems, the unit is well designed and, so far, is very rugged and reliable. Just a few corrections to their design and this would be almost a perfect mower.
From Dell / Intel® New Paradigms in Design Work Scott Hamilton, vertical market strategist for Dell Precision workstations, 5/2/2013 3
Early in my career, I worked as a draftsman and remember the days of drawing on vellum with numbered pencils and Mylar with plastic lead. This was a fun experience in the sense that I ...
I've been using workstations for more than 10 years and love finding ways to get more performance from my system. With demanding professional applications that require more power each ...
A lasting memory from my first job as an engineer in an auto assembly plant is standing on hard concrete at six in the morning, vending-machine coffee clutched in hand, listening to ...
A quick look into the merger of two powerhouse 3D printing OEMs and the new leader in rapid prototyping solutions, Stratasys. The industrial revolution is now led by 3D printing and engineers are given the opportunity to fully maximize their design capabilities, reduce their time-to-market and functionally test prototypes cheaper, faster and easier. Bruce Bradshaw, Director of Marketing in North America, will explore the large product offering and variety of materials that will help CAD designers articulate their product design with actual, physical prototypes. This broadcast will dive deep into technical information including application specific stories from real world customers and their experiences with 3D printing. 3D Printing is
To save this item to your list of favorite Design News content so you can find it later in your Profile page, click the "Save It" button next to the item.
If you found this interesting or useful, please use the links to the services below to share it with other readers. You will need a free account with each service to share an item via that service.
Tweet This
6 
