will someone please describe lugging?

[SPYDERLK]

Yeah, Chris, stop making posts that are understandable and describe a situation anyone who has ever driven a manual tranny car or tractor could relate to.

Yeah. Understanding and relating to something that misses the key point is a good thing.

 

[MikePA]

Yeah. Understanding and relating to something that misses the key point is a good thing.

He didn't miss the point, nor did he post a bunch of professorial, Mech Eng college level gibberish. Why explain something in 2 or 3 sentences in English when a few paragraphs of mecheng technospeak will do.

What's lugging? Read Chris' reply.
Why is it bad? It can starve certain bearing of oil.

 

[SPYDERLK]

He didn't miss the point, nor did he post a bunch of professorial, Mech Eng college level gibberish. Why explain something in 2 or 3 sentences in English when a few paragraphs of mecheng technospeak will do.

What's lugging? Read Chris' reply.
Why is it bad? It can starve certain bearing of oil.

Sub nominal RPM [slow relative motion/spin rate between the two sides of the bearing] vs hi load is the point. He missed it. Sorry you didnt understand my gibberish. I was trying to describe the way oil lubricates by essentially separating the surfaces. Sorta like water skiing actually.
larry

 

[MikePA]

Sub nominal RPM vs hi load is the point. He missed it. Sorry you didnt understand my gibberish. I was trying to describe the way oil lubricates by essentially separating the surfaces. Sorta like water skiing actually.
larry

Thanks, I understand how oil works by forming a film between 2 surfaces. More like hydroplaning than water skiing.

BTW, how many people do you think use 'sub nominal' in everyday conversation?

By gibberish I didn't mean incorrect. I we don't communicate using words most people understand then we are not communicating. Sort of 'sub nominal' choice of words.

 

[SPYDERLK]

Quote MikePa: I we don't communicate using words most people understand then we are not communicating.

I recognize this and immediately edited my post to make it more clear - evidently while you were answering. Sub-nominal would be "below the manufacturers named values" - or in this case the named rpm range for engine use.

I also recognize that one has to write to the level of the reader and that this level varies widely. So its a near impossible task. I just try to cover all the pertinent issues clearly and correctly so that someone interested can dig thru it without an in depth knowledge of subject. If I fail to get it across with appropriate example and analogy there is always the option to ask a question prior to referring to the explanation as nonsense.

I would think that skiing is hydroplaning. What is the difference?
larry

 

[MikePA]

I didn't say it was nonsense, I said it was gibberish, i.e., it ddn't communicate.

Hydroplaning, a loss of steering control when a layer of water prevents direct contact between a vehicle's tires and the road surface, i.e., the water between the tire and road acts just like oil does between 2 surfaces in an engine. Three surfaces are involved in each situation;

Tire, water, road surface
Bearing, oil, crankshaft

Planing, a method by which the hull of a boat (or a water ski) skims over the surface of the water rather than plowing through it.

I don't see the analogy with water skiing.

 

[Soundguy]

Yeah, Chris, stop making posts that are understandable and describe a situation anyone who has ever driven a manual tranny car or tractor could relate to.

I know.. I know.. my bad... evn though I said 'in short'.. I should have typed out a 3 page disertation on all of the statics and dynamics on the flywheel.. loads.. motion, time and all.. and really made something that nothing but an engineer or a math major could read thru.. silly me for typing something a tractor newbie might understand.

I'll go stand in the corner.. now where's my pointy hat at??


Soundguy

 

[SPYDERLK]

I didn't say it was nonsense, I said it was gibberish, i.e., it ddn't communicate.

Hydroplaning, a loss of steering control when a layer of water prevents direct contact between a vehicle's tires and the road surface, i.e., the water between the tire and road acts just like oil does between 2 surfaces in an engine. Three surfaces are involved in each situation;

Tire, water, road surface
Bearing, oil, crankshaft

Planing, a method by which the hull of a boat (or a water ski) skims over the surface of the water rather than plowing through it.

I don't see the analogy with water skiing.

That is the trouble with far reaching analogies. They approximate, leading to the need for too much precise extrapolation by the interpreter in order to get the actual meaning. Many key points are issues of nuance, that if missed lead to things that dont add up right. That is why I dont try to convey a complex issue in a sound byte.

It seems, in my #6 above I introduced too much information, that altho I tried to connect together, didnt. Our carefree analogies tho, are too brief. In coddling the attention span they leave out too much. Viscosity is one thing. The differences in relative motion between tires rolling, planing, and a bearing turning is another. The rings sorta hydroplane/ski. The working of plain bearings is related. Both deserve a skeptical look in terms of comparison to the analogies using water as the fluid.
Its kind of like neglecting to move the "road" when testing aerodynamics of a car in a wind tunnel. How tedious - but must be done if you want your interpretatation to jibe with reality.
larry

 

[MikePA]

That is the trouble with far reaching analogies. They approximate, leading to the need for too much precise extrapolation by the interpreter in order to get the actual meaning. Many key points are issues of nuance, that if missed lead to things that dont add up right. That is why I dont try to convey a complex issue in a sound byte. It seems, in my #6 above I introduced too much information, that altho I tried to connect together, didnt. Our carefree analogies tho, are too brief. In coddling the attention span they leave out too much.

This is similar to the emails I get from engineers at work. Every issue is complex and filled with nuance. I ask them what time it is and they tell me how a watch works. Here at work, (may not be the case here) I think they respond with a dissertation so the recipient will be so snowed, that any conclusion can be drawn from their answer. Either that or they simply like showing off. "On the one hand, blah, blah, blah.Yet on the other hand, blah, blah, blah."

It's got nothing to do with 'coddling the attention span' it has to do with providing people with information they can use to make decisions or reach conclusions in a reasonable amount of time.

 

[jeffinsgf]

Well, I for one thought Larry's explanation was interesting and informative. I have known most of my life that "lugging" an engine was a bad thing -- but understanding why is helpful.

I also like the "if you can't accelerate, you're lugging..." shorthand. That really separates "lugging an engine" from "working an engine". When my grass is thick and I am going up hill with my 455, that sweet little Yanmar will snort a little black smoke and dig a little deeper -- but I can still push it harder without stalling -- that's working, not lugging.