Maker Pro
Maker Pro

Designed to break?

J

John Larkin

Jan 1, 1970
0
Just curious about this kind of thing:
http://blog.stayfreemagazine.org/2007/04/are_consumer_pr.html

Have any of you designed things to break?

Never. In electronics design, it would actually be difficult;
electronics doesn't have predictable wearout mechanisms like
mechanical parts do.

We design our stuff to be as reliable and as rugged as we reasonably
can.
I know about MTBF, by the way and do understand basic economics. This is
different.

We sometimes calculate product MTBF using the Bellcore standards. Our
actual field-failure rate on most products is a lot better than the
calculations predict.

As far as consumer products go, if you buy the cheapest stuff, expect
it to break sooner. A $29 microwave oven can't be expected to be very
good. My GE microwave lasted 15 years; my VW threw a gear after 14. My
Tek scopes, Sony camera, Vaio laptop, home furnace, garage door
opener, are all 5-15 years old and working fine. I'm looking at an art
deco electric clock on my desk, made in the 1930's, that still keeps
perfect time.

Tektronix did one sampling plugin that used mercury batteries to
back-bias the schottky sampling diodes. They were special welded-tab
button cells, very hard to get at, and soldered into the circuit. They
are very difficult to replace, and last a few years.


John
 
J

Joerg

Jan 1, 1970
0
Same here. Absolutamente not.
Never. In electronics design, it would actually be difficult;
electronics doesn't have predictable wearout mechanisms like
mechanical parts do.

We design our stuff to be as reliable and as rugged as we reasonably
can.




We sometimes calculate product MTBF using the Bellcore standards. Our
actual field-failure rate on most products is a lot better than the
calculations predict.

As far as consumer products go, if you buy the cheapest stuff, expect
it to break sooner. A $29 microwave oven can't be expected to be very
good. My GE microwave lasted 15 years; my VW threw a gear after 14. My
Tek scopes, Sony camera, Vaio laptop, home furnace, garage door
opener, are all 5-15 years old and working fine. I'm looking at an art
deco electric clock on my desk, made in the 1930's, that still keeps
perfect time.

Tektronix did one sampling plugin that used mercury batteries to
back-bias the schottky sampling diodes. They were special welded-tab
button cells, very hard to get at, and soldered into the circuit. They
are very difficult to replace, and last a few years.

My old Minolta had a mercury cell. The trick I used was to get a low
cost modern watch battery and to get down from its 1.55V to the 1.35V of
a mercury cell I hung a OA91 Ge diode in series. The voltage was dead
on. Works like a champ again, just in time for when our foxes had their
kits.

"Designed to break" brings up some grief we (and probably lots other
folks in the US) experience a lot: Malibu Light timers. The last plastic
gear before the big timing wheel is usually shot after 3 years. I've
asked them twice how to get spares because it's easy to replace. No
answer. Silence. So every time this 5c part breaks we have to either buy
a new timer-transformer for $40 or so or wait until a whole set with
transformer and ten lights comes up in a sale for around $30. Quite
wasteful, considering that only the timer-transformer needs to be replaced.
 
P

Paul Hovnanian P.E.

Jan 1, 1970
0
Charles said:
Just curious about this kind of thing:
http://blog.stayfreemagazine.org/2007/04/are_consumer_pr.html

Have any of you designed things to break?
Nope.

I know about MTBF, by the way and do understand basic economics. This is
different.

I don't think things are designed to break. Not even MS Windows. Its
built broken and becomes obsolete when support is discontinued. But I
digress.

Economics dictates a point of diminishing return for an investment in
additional MTBF. In addition, economics limits the market value of
designing in maintainability. An example will illustrate my point: Some
time ago, I did research prior to selecting a flat panel TV set. One
attribute mentioned in reviews was the expected life of the display.
Plasma sets were the worst, tending to darken with age. LCD displays
were better, but their life was determined by the life of the backlight
source. Huh? In most cases, this is a couple of fluorescent lamps. It
should be a no brainer for the average consumer to snap in some new
lamps if the set were designed to make the job simple. But they (the
manufacturers) figure that after 5 years, the average consumer will be
willing to pitch the set out anyway. There are too few of us who would
change our purchase decision based upon this detail, so it isn't worth
the additional cost.

I don't think its as much about the possibility of future sales based on
a shorter product life. After all, the consumer who is in the market for
a replacement unit probably perceives the quality of their original
selection to be low, having just experienced a failed unit. This
customer is more likely to select another brand, so that's a lost sale
one way or the other.
 
J

Joerg

Jan 1, 1970
0
Paul said:
I don't think things are designed to break. Not even MS Windows. Its
built broken and becomes obsolete when support is discontinued. But I
digress.

Economics dictates a point of diminishing return for an investment in
additional MTBF. In addition, economics limits the market value of
designing in maintainability. An example will illustrate my point: Some
time ago, I did research prior to selecting a flat panel TV set. One
attribute mentioned in reviews was the expected life of the display.
Plasma sets were the worst, tending to darken with age. LCD displays
were better, but their life was determined by the life of the backlight
source. Huh? In most cases, this is a couple of fluorescent lamps. It
should be a no brainer for the average consumer to snap in some new
lamps if the set were designed to make the job simple. But they (the
manufacturers) figure that after 5 years, the average consumer will be
willing to pitch the set out anyway. There are too few of us who would
change our purchase decision based upon this detail, so it isn't worth
the additional cost.

There is one: Me :)

I don't think its as much about the possibility of future sales based on
a shorter product life. After all, the consumer who is in the market for
a replacement unit probably perceives the quality of their original
selection to be low, having just experienced a failed unit. This
customer is more likely to select another brand, so that's a lost sale
one way or the other.

Not necessarily. It depends on whether the failure was premature and how
the manufacturer dealt with it. If it was premature and they let me
hang, refusing to furnish spare parts and so on, yes, they'll earn a
pretty much eternal entry on our "Do not purchase anymore" list.
 
H

Homer J Simpson

Jan 1, 1970
0
"Designed to break" brings up some grief we (and probably lots other folks
in the US) experience a lot: Malibu Light timers. The last plastic gear
before the big timing wheel is usually shot after 3 years. I've asked them
twice how to get spares because it's easy to replace.

Take the new one and make a mold from it (silastic RTV?). Cast new gears as
needed from two part epoxy. You could even try a Metal Molder!



--
..

--
..
..
..
..
..
..
..
..

--
 
J

Joerg

Jan 1, 1970
0
Homer said:
Take the new one and make a mold from it (silastic RTV?). Cast new gears as
needed from two part epoxy. You could even try a Metal Molder!

Yeah, I just wanted to avoid that mess ;-)

I mean, what's wrong with offering a simple spare part to their
customers? Other companies like Bissell (vacuums) do their best to make
customers happy by sending spares. Often they don't even charge
anything. Is there a better supplier than Intermatic for these timers?
 
H

Homer J Simpson

Jan 1, 1970
0
Yeah, I just wanted to avoid that mess ;-)

I mean, what's wrong with offering a simple spare part to their customers?
Other companies like Bissell (vacuums) do their best to make customers
happy by sending spares. Often they don't even charge anything. Is there a
better supplier than Intermatic for these timers?

I have a digital one - starts at sunset and runs for 1, 2, 3 ... hours.
 
M

mpm

Jan 1, 1970
0
On May 29, 5:39?pm, John Larkin

Well, I guess that rules all of us out as being missile defense
contractors....
(Technically, I guess you could say those are designed to break!)

-mpm
 
J

Joerg

Jan 1, 1970
0
Homer said:
I have a digital one - starts at sunset and runs for 1, 2, 3 ... hours.

We were cured of those. Bought one, ran for 2 hours minus 50% plus a few
hundred percent. Exchanged it, same thing. Later I peeked into one that
someone else was throwing away for the same reason. A concoction of
chips and electrolytics, like many of those ill-fated 555 circuits. Oh
man. I guess some "engineer" hadn't figured out yet how to do a long
range timer around a CD4060. What are they teaching them these days?
 
P

Paul E. Schoen

Jan 1, 1970
0
Charles said:
Just curious about this kind of thing:
http://blog.stayfreemagazine.org/2007/04/are_consumer_pr.html

Have any of you designed things to break?

I know about MTBF, by the way and do understand basic economics. This is
different.
I've never intentionally done that, but many things created from technology
will eventually become obsolete. Sometime, parts are no longer made. A
product I designed, the Ortmaster, uses a parallel port in a special way
and must have MSDOS to run the software. New computers don't come with
MSDOS, and even if you could install it, parallel ports are often no longer
supplied.

In a way, this is fortunate for me, because I am setting up an upgrade
option where I will replace the internal PC Board and supply new Windows
software that can run the system through a serial port or USB. This is a
device that sells for $3000, and the retrofit will sell for about $1000,
for a parts cost of about $100.

This new product contains a PIC, and it would be possible to program
planned obsolescence into the product. It could have a RTC, so after a
certain period of time, it could shut down operation. I was considering
something similar, but not so drastic. The device should be calibrated on a
yearly basis, and the calibration data is contained in the program memory
(which is supposed to be better than EEPROM). The calibration date could be
included, and the software could check this date against its own RTC and
pop up a warning that calibration is due.

Actually I think this is a good idea, because it is very important that
calibration accuracy be assured, and many of these units that I get in for
repair are long overdue. Sometimes when I repair them, the calibration can
still be checked, and usually is pretty close, but sometimes it is off by a
significant amount. I charge a flat rate of $100 for NIST calibration, and
an extra $100 for repair, plus shipping, so it's reasonable. However, most
of the shops that have them don't want to part with them for even a few
days, so they nurse them along until they stop working.

Paul
 
M

Michael A. Terrell

Jan 1, 1970
0
Joerg said:
Yeah, I just wanted to avoid that mess ;-)

I mean, what's wrong with offering a simple spare part to their
customers? Other companies like Bissell (vacuums) do their best to make
customers happy by sending spares. Often they don't even charge
anything. Is there a better supplier than Intermatic for these timers?


I used a digital Intermatic timer to turn a window air conditioner on
and off for years I haven't needed it much, since I got sick. The AC
is on almost year round since I've become disabled. the motorized one
on the water heater has been in use for eight years and still works
fine. The older ones had the motors fail at about five years, but
spares were sold at Home Depot.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
M

Michael A. Terrell

Jan 1, 1970
0
mpm said:
On May 29, 5:39?pm, John Larkin

Well, I guess that rules all of us out as being missile defense
contractors....
(Technically, I guess you could say those are designed to break!)


Microdyne built command destruct receivers to destroy off course
rockets.


--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
 
P

Paul Hovnanian P.E.

Jan 1, 1970
0
Joerg said:
There is one: Me :)

Well, me too. But manufacturers don't cater to us. If you want a
microwave oven, you get to select between the models that are aimed at
the mass market.
Not necessarily. It depends on whether the failure was premature and how
the manufacturer dealt with it. If it was premature and they let me
hang, refusing to furnish spare parts and so on, yes, they'll earn a
pretty much eternal entry on our "Do not purchase anymore" list.

They (consumer electronics manufacturers) want to sell you another unit.
If they sell you a repair part, they've lost ther sale of a new unit. If
they don't sell you a repsir part and you go away thinking dark thoughts
about them, that's the same sale they've lost.
 
P

Paul Hovnanian P.E.

Jan 1, 1970
0
mpm said:
The Windows operating system???

It was built broken. After a time, they just stop supporting it.

All software is built broken. Bits don't wear out. The bugs just become
exposed over time as probability dictates that eventually, the
combination of conditions necessary to unearth them will occur.
 
H

Homer J Simpson

Jan 1, 1970
0
Just curious about this kind of
thing:http://blog.stayfreemagazine.org/2007/04/are_consumer_pr.html

Have any of you designed things to break?

I know about MTBF, by the way and do understand basic economics. This is
different.
The Windows operating system???

Reminds me of:

http://funnies.paco.to/cars.html

If Operating Systems Drove Your Car to the Store

MS-DOS
You get in the car and try to remember where you put your keys.

Windows
You get in the car and drive to the store very slowly, because attached to
the back of the car is a freight train.

Windows NT
You get in the car and write a letter that says, "go to the store." Then you
get out of the car and mail the letter to your dashboard.

Macintosh System 7
You get in the car to go to the store, and the car drives you to church.

UNIX
You get in the car and type grep store. You are given a list of 400 7-11's
in your area and 50 grocery stores. After picking one and reaching speeds of
200 miles per hour en route, you arrive at the barber shop.

OS/2
After fueling up with 6000 gallons of gas, you get in the car and drive to
the store with a motorcycle escort and a marching band in procession.
Halfway there, the car blows up, killing everybody in town.

AIX
During the whole trip to the store, your gas meter reads full and the car
runs fine. On the way home, under the strain of the extra cargo, the car
inexplicably runs out of gas, even though the meter still reads full.
(SIGDANGER)

Taligent/Pink
You walk to the store with Ricardo Montalban, who tells you how wonderful it
will be when he can fly you to the store in his Lear jet.

S/36 SSP (mainframe)
You get in the car and drive to the store. Halfway there you run out of gas.
While walking the rest of the way, you are run over by kids on mopeds.

OS/400
An attendant locks you into the car and then drives you to the store, where
you get to watch everybody else buy filet mignons.

VAX/VMS
You use up tremendous amounts of gas to go very slowly and only get to see
an image of the store.
 
A

amdx

Jan 1, 1970
0
John Larkin said:
Never. In electronics design, it would actually be difficult;
electronics doesn't have predictable wearout mechanisms like
mechanical parts do.


As far as consumer products go, if you buy the cheapest stuff, expect
it to break sooner. A $29 microwave oven can't be expected to be very
good. My GE microwave lasted 15 years;
John
I'm still using a Frigidaire microwave oven we purchased in 1983!
I did replace the lightbulb once or twice over the years. Uses a good
old mechanical timer and a pot to set the duty cycle.
Mike
 
Top