Merits of fool proof design (sss hub / wheel design)

[mitt]

True, but the 5-spokes are specifically trying to be lightweight.

They could have used a different pattern that was even lighter than this but only 1 way.  It is a bad design period, and probably would have never left an American design company drawing board due to the litigation it could create doing a 30 second DFMEA since it is a serviceable item and is 100% certain of being removed and installed wrong at some point.

Like I said above, this is at least the 3rd time I have seen this issue on the DMF, and we are probably the cream of the crop for DIY'ers.


mitt

[Popeye the Sailor]

Okay, MrIncredible - I concede. It's a bad design. You've made your point.

Just more curious than anything-I'm often on the design end of things-repair isn't typically a concern

[ducpainter]

<snip>

Like I said above, this is at least the 3rd time I have seen this issue on the DMF, and we are probably the cream of the crop for DIY'ers.


mitt

maybe for the information available, but the skill of knowing exactly what you're looking at and applying that info is probably average for the population.

[Spck31]

Sticking around for more of this great thread.

really amazing odd failures, rear wheel one surprised me.. and be sure i will check rollers & belt on my next oil change.

[sbrguy]

we are debating how some think an engineeer made a bad design on putting:

4 holes that fit 4 pegs.

and that there are 4 slots in between.

Last time i checked when you put a wheel on a hub you line up the studs with the holes in the rim that fit it, maybe that is TOO difficult for most to realize but hey i could be wrong.

what we need is engineers to DO THEIR JOB and put INSTRUCTIONS on ALL PARTS on how to assemble EVERYTHING.  That way this would have never happened. neither would any other malfunction of assembly, because we all know that everyone reads directions.

[mitt]

maybe for the information available, but the skill of knowing exactly what you're looking at and applying that info is probably average for the population.

Really?  In my world of bike friends, I would put them below average in mechanical skills to what I see posted in tech.

mitt

[mitt]

Last time i checked when you put a wheel on a hub you line up the studs with the holes in the rim that fit it, maybe that is TOO difficult for most to realize but hey i could be wrong.

So, you have never made a mistake then right?  Never had a bad day, or were distracted by something / someone while working?  Must be nice.

Also, just think how fun life would be if every thing we engineers designed could be assembled wrong - might take an hour to do something basic like connect a monitor cable if you had to pin out every wire between devices.

How many times have we seen the conical spacer for dss monsters put in wrong on here?  Another case were it is easy to do, but hard to detect it is wrong until bad things happen.

mitt

[ducpainter]

Really?  In my world of bike friends, I would put them below average in mechanical skills to what I see posted in tech.

mitt

I think so.

There are many more people here that don't have skills than there are that do IMO.

The people that have experience seem to have lots of it. That is a bit unusual I think.

Maybe we're saying the same thing...just different.

[sbrguy]

So, you have never made a mistake then right?  Never had a bad day, or were distracted by something / someone while working?  Must be nice.

Also, just think how fun life would be if every thing we engineers designed could be assembled wrong - might take an hour to do something basic like connect a monitor cable if you had to pin out every wire between devices.

How many times have we seen the conical spacer for dss monsters put in wrong on here?  Another case were it is easy to do, but hard to detect it is wrong until bad things happen.

mitt

ok so if i have this right, you want engineers to basically make everything idiot proof.

i can agree with that 100%, you are right.

just put instructions on EVERY SINGLE PART on how it is supposed to be used and assembled.  That way everyone can read it and put it together correctly and also someone "can't have a bad day and mess up" because the instructions are always there and can't ever say they "didn't know or forgot". 

because we have already established that putting a connection with 4 pegs into 4 round holes when there are "only" 4 round holes to put the pegs in is an obviously bad design.

[Popeye the Sailor]

because we have already established that putting a connection with 4 pegs into 4 round holes when there are "only" 4 round holes to put the pegs in is an obviously bad design.

There are 8 holes to put four pegs into. Only one way is right, but nothing prevents you from doing it wrong.

That right there is a poor design.

How many engineers need to state this to make you happy?

[ducpainter]

There are 8 holes to put four pegs into. Only one way is right, but nothing prevents you from doing it wrong.

That right there is a poor design.

How many engineers need to state this to make you happy?

I'm a lowly painter...

and I think it's a dogshit design.

Does that count?

[mattc7]

the design might not be perfect, but the user gets all the blame for not caring to do it correctly. It's an easy error to make, but equally easy to avoid

[mitt]

ok so if i have this right, you want engineers to basically make everything idiot proof.

Only if it is easy to do without sacrificing some critical functionality or adding too much complexity or cost.

just put instructions on EVERY SINGLE PART on how it is supposed to be used and assembled.  That way everyone can read it and put it together correctly and also someone "can't have a bad day and mess up" because the instructions are always there and can't ever say they "didn't know or forgot". 

How many languages?  I am not sure where the logic is with instructions.  If things "fall into place", no instructions needed.

I might cut out all this off topic BS into a new thread since this one was so good before we shat in it.

mitt

[Popeye the Sailor]

ok so if i have this right, you want engineers to basically make everything idiot proof.

i can agree with that 100%, you are right.

just put instructions on EVERY SINGLE PART on how it is supposed to be used and assembled.  That way everyone can read it and put it together correctly and also someone "can't have a bad day and mess up" because the instructions are always there and can't ever say they "didn't know or forgot". 

because we have already established that putting a connection with 4 pegs into 4 round holes when there are "only" 4 round holes to put the pegs in is an obviously bad design.

Where do you get your arguments from?

No one said anything about idiot proof-that assembly could be redesigned at minimal cost to prevent this from happening, ever.

Instructions are moot-clearly the person assembling it knew where the wheel had to go, and mounted it wrong, because mounting it wrong was easy to do, which is the core of the issue.

I'm not sure the topic is even debatable.

[Christian]

I still think that the four post, four hole design - while not technically idiot proof - is a reasonable one.

Ducatis are pretty straightforward, but there are certain things that one needs to pay attention to when working on them. Many folks know that valve adjustments, for example, can be tricky. There's a lot of patience required when working on these bikes and some of the procedures are more of an art form than a science. I think that's part of the appeal.

I'd rather my wheel be as light as possible and have a margin of error for improper install.