That would be two degreed engineers and two "other guys"

 

Sorry eyeoutthere, only knew of Jon's status for certain. Not that it would have made a difference, but i didn't see your response till after i posted mine.

I thought about putting 'at least' but I can't type fast enough to get all my thoughts down, and i'm a fast typist!

Make that 'At LEAST two degreed engineers'

Who knows, maybe Mr. BigXL is an engineer too....

-brent

 

I've got an engineering degree also but, that doesn't always mean anything. There is another guy up here with a BSME too and he can't change the spark plugs in his car!

 

Maybe not, but he could probably design a spark plug.

I agree that being able to perform tasks such as repair/rebuild or especially understand and operate machine tools which make the parts one designs is very important. Every day I see part drawings ("blueprints") designed by someone who doesn't understand how parts are made economically. This just costs their company and ultimately the end user more money than it needs to.

We are getting farther away from the "throw it over the wall" design philosophy where the designer does his/her thing and says "make the SOB the way I designed it!" forgetting the clause "no matter what it costs in money and time" which automatically attaches itself. Part of that comes from EE or Engineer Ego, which is a lot like DE or Doctor Ego, and part comes from ignorance of the real world.

The best engineers and doctors I have been associated with don't have those diseases. They are open minded, practical, thinking individuals often with diverse interests. At least one practices here.

If you understand "how the world works" mechanically, biologically, and cosmologically, and have hands on experience in multiple areas, you might be a better engineer or doctor. IMO, not enough engineers or doctors, to name just a few professions, expand their minds outside of their professions. More's the pity.

End of off-topic rant.

Oh, shouldn't we use lb-ft rather than ft-lb? The force should probably come first. I've not heard meter-Newtons ever used. I'm as guilty as most everyone else on this.

 

Yes, because it is the force (lbs. or Newtons) that changes and the distance for calculation (in., ft., or meter) stays constant.

 

Yeah, I agree with that. I wasn't trying to claim that all engineers could 'do it all'. I even put a little clause in one of my previous post about the possibility of them being in error, BUT in this case they weren't

Anyone else ever noticed this trend: the ability to work with ones hands and use common sense in design increases with intelligence, GPA, and education level up until a certain threshold and then it plummets as the individual's GPA approaches a 4.0 or they become a PHD. " It's quite the anomaly really, ha" -old school

-brent

 

PHD as in "Piled Higher and Deeper"? That's if you assume what BS stands for.

Not always true, however. One of the best camshaft designers in the business was a PHD candidate in particle physics. At least a 4.0 guy. A lot of us run cam profiles he designed.

 

Hello Beaker. I just read it again, and the page says:

"English units of torque are pound-inches or pound-feet; the SI unit is the Newton-meter."

It's the first sentence of the 2nd paragraph. also, i never said ft/lbs or ft per lb.

hey brent, it's not a spring rate. Like i said, the / is not a division sign, it's means 'per'. but you said that is incorrect also.

I'm not an engineer, and only have 1 year of high school physics and 1 year of college physics, but it's my understanding that torque is a rotational force, measured in pounds of pressure applied on a 12" lever arm, and i believe moving through 12" of rotation. Therefore, 350 lbs/ft means the rotational force is the same as having 350 lbs on a lever arm 12" long and having that force (due to gravity however) create the rotational force.

Now on the issue of saying, "foot pounds", i thought it was not official convention, but simply vernacular. Don't you think "350 lbs of torque" is more accurate than, "350 foot pounds" ?

 

You can slice it and dice it any way you want, but you are incorrect. "/" is CONVENTIONALLY used as the "divide" sign, and the result of a division are often express as "per".... as in miles per hour..... or miles travelled DIVIDED by the hours it took to go that difference.

Torque is the product (multiplication) of two numbers.... the normal force acting on a lever, and the length of the lever. The end product is generally referenced as "lb-ft" (or sometimes "ft-lb"). And, NO it does not make any sense all to suggest that "350 lbs of torque" is more accurate than "350 foot pounds"...... only the last one is correct. And NO the lever does not have to be 12" long, and the amount the lever moves is not relevant.

 

Geesh... the answer to the topic question is simple but by reading this thread you wouldn't know it!

 

so all the auto manufacturer's brochures, and all the car mags are incorrect when they say 350 lbs/ft ? it is accepted by everyone except you?

Could you please post some links, like this one again HowThingsWork which contains this quote:

"To calculate the torque, you just multiply the force by the distance from the center. In the case of the lug nuts, if the wrench is a foot long, and you put 200 pounds of force on it, you are generating 200 pound-feet of torque. If you use a 2-foot wrench, you only need to put 100 pounds of force on it to generate the same torque."

the 12" lever concept is an integral part to the equation. Of course there is no 12" lever arm in your engine, it's more like 3", which is even more impressive cuz it takes 1400 lbs of pressure on a 3" lever arm to create the same torque as 350 lbs on a 12" lever arm.
are you really an engineer?

 

It is not accepted by anyone who knows what they are talking about.

That statement basically says Torque = normal force X lever arm. Same thing I explained to you. What part of this do you not understand?

BSME, *** laude from NJ Institute of Technolgy

MS in Engineering, NJIT

Licensed Professional Engineer in the State of NJ, and qualified to give expert testimony in the NJ Court system relative to matters concerning Mechanical Engineering. (I'll be glad to send you my License # if you doubt me.)

Moderator - CZ28.com Advanced Tech board

40 years hands on experience as a Mechanical Engineer.

Any more questions?

 

MrBig no offense but you seem to be grossly missing the point.

This is very straight forward. Almost elementary. I am getting frustrated just reading this post after several engineers have made it more than obvious what the real facts are.

I'm not yet a degreed Engineer but I've passed all the classes and then some (over 2 years, being calc 1,2,3, physics 1, 2, etc.. )where we covered this concept, so I too have the credentials to make a case.

For one, you wanted a quote, here is a quote right from Car and Driver.

"The SOHC 12-valve, 4.0-liter V-6 with 202 horsepower and 235 pound-feet, also running in the Ranger pickup, opens the Mustang’s power résumé. "

Yes that's pound-feet, not pound per foot or pound/ft etc.

Second, no matter how you want to argue the point the mathematical equation is Torque=force times distance.

Never ever is "/" used to describe multiplication by a mathematician or engineer. And it does mean per.

If you do see it that way then realize that the people who physically type up the marketing aren't the engineers. They are the business majors and marketing majors that in my school spend most of there time drinking and could care less about math

Furthermore Torque can be represented by division but that is power over angular velocity not distance.

 

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I, on the other hand, have no education. But, I've still always seen the "/" and "per" as meaning "divided by" too

I also tried to look on some magazine sites for examples of ft/lbs and couldn't find any.

 

Of course. Who else can they get to work at a nuclear reactor?

I'm not too educated either, but my last two job titles had engineer in them. Go figure.