Farm Equipment - hanging christmas lights,ladder and engine math

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hanging christmas lights,ladder and engine math

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Topic: hanging christmas lights,ladder and engine math

Posted By: mlpankey
Subject: hanging christmas lights,ladder and engine math
Date Posted: 17 Dec 2011 at 3:56pm

well all you engine building motor heads as I have probably already hung your christmas lights on the house or shop with aid of a extension ladder. In a few weeks it will be time to prop the ladder up against the wall again to remove the lights and pack them away for anothe year. This is a good time to do a engine math experiment. When ladders in place and you climb it place a piece of tape where the top of ladder touches the wall. Then come down to the ground and pull a measuring tape from the wall out past the ladders feet several feet. Pull the ladder feet out one foot further from the wall then measure the distance from where the top of the ladder was to where it is now . Record this measurment everytime you move the feet of the laddder out another foot. As the ladders angle at the feet gets more severe to the ground with every foot moved the top of the ladder should move down the wall further than it did the first foot the feet was moved out from the wall and so on. Now then assuming that you can move the ladder out one foot each time and everytime in the same number of seconds we have the first measurment needed for acceleration . With the recorded distance traveled each time the ladder was moved we can plot the acceleration of the ladders end and at what angle it would have accelerated the most in the same time to achieve the greater distance traveled downward. This is how rod length changes affect piston speed at given crank angles. Enjoy and Merry Christmas .

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people if they don't already know it you can't tell them. quote yogi berra

Replies:

Posted By: Jeff Z. NY
Date Posted: 17 Dec 2011 at 4:05pm

Holy %^$*.
Give that guy a drink.
He ain't drunk yet.

You'll know when he's drunk.
He'll start talking about chicks and their curves.

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I Love Meatballs and Dumplings on Toast with Gravy and Rosemary and ??? {Open For Suggestions}

Posted By: Jeff Z. NY
Date Posted: 17 Dec 2011 at 4:08pm

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I Love Meatballs and Dumplings on Toast with Gravy and Rosemary and ??? {Open For Suggestions}

Posted By: Chris/CT
Date Posted: 17 Dec 2011 at 6:22pm

MLP, Your commitment to engine geometry,etc is great. It's alway's a pleasure to see mechanics at whatever there trade may be, thinking about the principals, etc. Now, I would like you take the next step and start thinking in another "box", create a "new" engine that will replace internal combustion and rid us this stranglehold to petroluem.

Posted By: mlpankey
Date Posted: 17 Dec 2011 at 6:43pm

hot air engines have been around longer than I have

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people if they don't already know it you can't tell them. quote yogi berra

Posted By: RickUP
Date Posted: 17 Dec 2011 at 6:45pm

Way back this summer, I fell off my ladder. It felt like my engine threw a rod. Now I know why.

Posted By: mlpankey
Date Posted: 17 Dec 2011 at 7:05pm

RickUP wrote:

Way back this summer, I fell off my ladder. It felt like my engine threw a rod. Now I know why.

when the computer misfires the electrical circuits and you miss the rung its like having cylinders cross wired ,stuff gets busted and broken.

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people if they don't already know it you can't tell them. quote yogi berra

Posted By: Pa.Pete
Date Posted: 17 Dec 2011 at 10:20pm

Planky,
I may be wrong but I see a difference in your comparison of the ladder and an engine rod, the difference being the ladder only moves horizontally. The piston rod end turns in a circle directly proportional to the crank RPM, with the piston connected to the other end of the rod it too is proportional to the crank RPM.
Pete

Posted By: Dipstick In
Date Posted: 17 Dec 2011 at 10:42pm

That may well be PaPete, but I still can't get the blanky blanking ladder to unfold, let alone crawl up it.

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You don't really have to be smart if you know who is!

Posted By: steve(ill)
Date Posted: 17 Dec 2011 at 11:43pm

no gasoline needed--- use natural gas .. plenty of that in the US.

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Like them all, but love the "B"s.

Posted By: DougS
Date Posted: 18 Dec 2011 at 12:48am

steve(ill) wrote:

no gasoline needed--- use natural gas .. plenty of that in the US.

Only until everyone starts using it.

Posted By: SHAMELESS
Date Posted: 18 Dec 2011 at 1:09am

<<<<<has lots of "natural gas" !!! and is always willing to share it!!

Posted By: Jeff Z. NY
Date Posted: 18 Dec 2011 at 6:14am

steve(ill) wrote:

no gasoline needed--- use natural gas .. plenty of that in the US.

Right,and nancy said we should use more of it and get away from fossil fuels.

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I Love Meatballs and Dumplings on Toast with Gravy and Rosemary and ??? {Open For Suggestions}

Posted By: maurice
Date Posted: 18 Dec 2011 at 6:21am

Or don't use the ladder! We use a looong painters extension pole, with an old paint roller frame cut and bent into a hook, stand on the ground and hook those lights up there, and same to take down. Of course, I had to go up the ladder to put the stainless screws or hooks up at the roof the first time. Also works for trees.

Posted By: mlpankey
Date Posted: 18 Dec 2011 at 2:06pm

Pa.Pete wrote:

Planky,
I may be wrong but I see a difference in your comparison of the ladder and an engine rod, the difference being the ladder only moves horizontally. The piston rod end turns in a circle directly proportional to the crank RPM, with the piston connected to the other end of the rod it too is proportional to the crank RPM.
Pete

ladder never moved to horizontal it moved linear.If it had they would be no angle from the feet to the ground or angular movement. A connecting rod converts linear or rectilinear motion into rotating motion .

Analogy between Linear Motion and Rotational motion^{#cite_note-9 - [10]}

Linear motion	Rotational motion
Displacement = $\mathbf{s}$	Angular displacement = θ
Velocity = $\mathbf{v}$	Angular velocity = ω
Acceleration = $\mathbf{a}$	Angular acceleration = α
Mass = $\mathbf{m}$	Moment of Inertia = $\mathbf{I}$
Force = $\mathbf{F} = \mathbf{m} \mathbf{a}$	Torque = $\Tau = \mathbf{I} \alpha$

chart from our friends at wikepedia

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people if they don't already know it you can't tell them. quote yogi berra

Posted By: mark vaughn
Date Posted: 18 Dec 2011 at 2:23pm

Okay Pankey, using a ladder leaning against a wall is a good example in compairing how different rod lengths affects the piston speeds in an engine. When they first started alternating rod length in racing engines, they were worried about piston to cylinder wall load. As they started building engines with longer strokes it also brought the piston to cylinder load to the critical point. The way you correct this is to put a longer rod in the engine. It is called "altering rod to stroke ratio". You figure rod to stroke ratio by dividing the rod length of your engine into the stroke length of your crankshaft. An example would be: 5.700 stroke divided by 3.480 rod length = 1.637 rod to stroke ratio. But remember! Moving the ladder from the wall is in comparison to having a longer stroke crankshaft in the engine and causing the rod to stroke ratio, or piston load, to be more critical with the same length rod (or ladder length). I know probably most of you are bored, so I will stop here. This knowledge all comes from years and years of building all different sizes engines. Merry Christmas and Happy New Years to everyone!!! Be safe in whatever you do!! Mark

Posted By: mlpankey
Date Posted: 18 Dec 2011 at 2:28pm

mark vaughn wrote:

Okay Pankey, using a ladder leaning against a wall is a good example in compairing how different rod lengths affects the piston speeds in an engine. When they first started alternating rod length in racing engines, they were worried about piston to cylinder wall load. As they started building engines with longer strokes it also brought the piston to cylinder load to the critical point. The way you correct this is to put a longer rod in the engine. It is called "altering rod to stroke ratio". You figure rod to stroke ratio by dividing the rod length of your engine into the stroke length of your crankshaft. An example would be: 5.700 stroke divided by 3.480 rod length = 1.637 rod to stroke ratio. But remember! Moving the ladder from the wall is in comparison to having a longer stroke crankshaft in the engine and causing the rod to stroke ratio, or piston load, to be more critical with the same length rod (or ladder length). I know probably most of you are bored, so I will stop here. This knowledge all comes from years and years of building all different sizes engines. Merry Christmas and Happy New Years to everyone!!! Be safe in whatever you do!! Mark

no its not showing more stroke but it is showing how going to a acute angle like the rod goes through with the cranks rotation makes a piston travel faster or slower at that angle . A 5.65 rod x3.76 stroke small block made a better stump puller . building engines since mid 80s and increasing the stroke at the expense of rod ratio always made more power than a good rod ratio with less stroke.

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people if they don't already know it you can't tell them. quote yogi berra

Posted By: mark vaughn
Date Posted: 18 Dec 2011 at 2:52pm

i totally agree and after they saw the difference of torque and power made by different rod lengths they did really did not worrie about cylinder loads that much

Posted By: mark vaughn
Date Posted: 18 Dec 2011 at 7:03pm

Yes experience does help when building and understanding engines. Been building mine since mid 70's so you are showing your intelligence if you have been building since the 80's. I admire people who know what they are talking about and not just rambling on about something. I build many ASCS 360 Sprint Car engines and they live in the 8500 RPM range. According to the track size, I use 6.00 to 6.125 rod length. The longer the rod length, the motor shows more torque and power in the higher RPM range. I meant in my previous post engine builders DID worry about cylinder loads. I had a typo and just noticed it. Sorry!!

Posted By: mlpankey
Date Posted: 18 Dec 2011 at 7:45pm

last dirt track motor was a 430 ci sb2 . 6 inch rod was long enough to keep it from blowing the tires up coming off the corner and seam not to nose over in the straight as quick as a 5.7 rod did. Engines forsale if you know anyone who needs it . I prefer bbc myself I have one of them that Harold Brookshires roller cam grind quits at 8500 from the late 80s. actually one could misconstrude that rod length alone makes more power higher in the rpm range . Actually I see the same peak but at a diferent rpm. I think the main reason goes back to the effective stroke being less on the long rod when intake valve closes abdc and the cylinder heads ability to fill in less time due to higher rpms. With v8 I worry more with deck heights that straighten the intake runners and shorten pushrods for less deflection than cylinder wall loading. i guess it comes from the drag strip.

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people if they don't already know it you can't tell them. quote yogi berra

Posted By: mark vaughn
Date Posted: 18 Dec 2011 at 10:10pm

I like your thinking and knowlege of racing engines Mr. Pankey. Im glad to have met you on this forum and you being a engine builder and Allis Chalmers man to. You just cant beat that. I am also a bbc man too. Merry Christmas

Posted By: Larry(OH)
Date Posted: 19 Dec 2011 at 5:30am

Hey Pank, sounds like you needed a set up on a dirt car to keep it planted

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'40 WC puller, '65 770 Ollie

*ALLIS EXPRESS contact*

I can explain it to you, BUT I cannot understand it for you!!

Posted By: Jeff Z. NY
Date Posted: 19 Dec 2011 at 8:42am

mlpankey wrote:

well all you engine building motor heads as I have probably already hung your christmas lights on the house or shop with aid of a extension ladder. In a few weeks it will be time to prop the ladder up against the wall again to remove the lights and pack them away for anothe year. This is a good time to do a engine math experiment. When ladders in place and you climb it place a piece of tape where the top of ladder touches the wall. Then come down to the ground and pull a measuring tape from the wall out past the ladders feet several feet. Pull the ladder feet out one foot further from the wall then measure the distance from where the top of the ladder was to where it is now . Record this measurment everytime you move the feet of the laddder out another foot. As the ladders angle at the feet gets more severe to the ground with every foot moved the top of the ladder should move down the wall further than it did the first foot the feet was moved out from the wall and so on. Now then assuming that you can move the ladder out one foot each time and everytime in the same number of seconds we have the first measurment needed for acceleration . With the recorded distance traveled each time the ladder was moved we can plot the acceleration of the ladders end and at what angle it would have accelerated the most in the same time to achieve the greater distance traveled downward. This is how rod length changes affect piston speed at given crank angles. Enjoy and Merry Christmas .

-------------
I Love Meatballs and Dumplings on Toast with Gravy and Rosemary and ??? {Open For Suggestions}

Posted By: Pa.Pete
Date Posted: 19 Dec 2011 at 8:54am

[/QUOTE] ladder never moved to horizontal it moved linear.If it had they would be no angle from the feet to the ground or angular movement. A connecting rod converts linear or rectilinear motion into rotating motion .

Analogy between Linear Motion and Rotational motion^{#cite_note-9 - [10]}

Linear motion	Rotational motion
Displacement = $\mathbf{s}$	Angular displacement = θ
Velocity = $\mathbf{v}$	Angular velocity = ω
Acceleration = $\mathbf{a}$	Angular acceleration = α
Mass = $\mathbf{m}$	Moment of Inertia = $\mathbf{I}$
Force = $\mathbf{F} = \mathbf{m} \mathbf{a}$	Torque = $\Tau = \mathbf{I} \alpha$

chart from our friends at wikepedia

[/QUOTE]

Yes I should of said linear not horizontal. If I question something please don't take offense, I'm just trying to learn a little.

Pete

Posted By: Jeff Z. NY
Date Posted: 19 Dec 2011 at 9:05am

mark vaughn wrote:

Yes experience does help when building and understanding engines. Been building mine since mid 70's so you are showing your intelligence if you have been building since the 80's. I admire people who know what they are talking about and not just rambling on about something. I build many ASCS 360 Sprint Car engines and they live in the 8500 RPM range. According to the track size, I use 6.00 to 6.125 rod length. The longer the rod length, the motor shows more torque and power in the higher RPM range. I meant in my previous post engine builders DID worry about cylinder loads. I had a typo and just noticed it. Sorry!!

In all due respect math helps but doesn't win races, the driver does.
I know a few drivers that can switch from their cars to the slowest cars on the track and still win.

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I Love Meatballs and Dumplings on Toast with Gravy and Rosemary and ??? {Open For Suggestions}

Posted By: mlpankey
Date Posted: 19 Dec 2011 at 9:18am

Pa.Pete wrote:

[/QUOTE

Analogy between Linear Motion and Rotational motion^{#cite_note-9 - [10]}

Linear motion	Rotational motion
Displacement = $\mathbf{s}$	Angular displacement = θ
Velocity = $\mathbf{v}$	Angular velocity = ω
Acceleration = $\mathbf{a}$	Angular acceleration = α
Mass = $\mathbf{m}$	Moment of Inertia = $\mathbf{I}$
Force = $\mathbf{F} = \mathbf{m} \mathbf{a}$	Torque = $\Tau = \mathbf{I} \alpha$

chart from our friends at wikepedia

[/QUOTE]

Yes I should of said linear not horizontal. If I question something please don't take offense, I'm just trying to learn a little.

Pete

[/QUOTE] Sorry if my responce made you feal that I was on the offence. I learn by asking questions and researching answeres just as everyone else does.

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people if they don't already know it you can't tell them. quote yogi berra

Posted By: Pa.Pete
Date Posted: 19 Dec 2011 at 9:47am

[/QUOTE]

Yes I should of said linear not horizontal. If I question something please don't take offense, I'm just trying to learn a little.

Pete

[/QUOTE] Sorry if my responce made you feal that I was on the offence. I learn by asking questions and researching answeres just as everyone else does. [/QUOTE]

Planky,

Your response didn't make me feel that way, I just didn't want you to think that! I will probably have more questions and I just wanted to state that ahead of time.

Pete