Mechanical Advantage

TreeMuggs

Treehouser
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I have put together a new article to teach my apprentice everything he should need to know about mechanical advantage: Mechanical Advantage Explained

It is still not finalized. I would love to get feedback from the Treehouse community on anything that I missed or screwed up. Really appreciate the support. Thank you.



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Damn dude, you're killing it with these articles. Just the right amount of simplicity/detail for an introduction
 
This is really excellent.
Easy to read, easy to understand.
 
That was a great write up Muggs.

What always fascinated me about MA was the actual mechanism. How was a pulley amplifying the force? It wasn't until someone described the round sheave as a series of levers that it clicked for me. . . I love these various setups.

Cheers

17426180_1314767751892496_7728444845886169840_n.jpg
 
I have rewritten this about 16 times, trying to get it right. Can't seem to get there..
Now I'm just ging to say what I mean, and if you don't like it, remember that this is not the language I was born into.

Get a better avatar!
The stuff you are putting out is absolutely first class, I've shown it to my apprentice and it made him way smarter.
Then people look at that stupid picture, and if they react like I do, they'll go:" Why should I believe anything that idiot has to say".

Get a better avatar.
The one you have works just fine for being on a forum, but it stinks for being the thoughtfull person behind this stuff.

Oooooooor maybe I'm just sensitive?
 
Mugg's got humility, humbleness, a plain n forthright manner of describing mechanical advantage, and a refreshing sense of humor.

Should be required high school reading!

Hopefully he's a bit Irish, and keeps iz avatar az iz, just to pizz Stig off!

GOod stuff Muggs, real good.

Jomo
 
What a great article Treemugs! It leaves all the guess work out! Pictures of tools with simple names and the examples of the tools being used. I am going to subscribe to your site. Thanks for posting this!
 
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Thank you to everyone for the support. This article was very well received across the board. So amazing to pour your heart into something and have an effect on others. My whole site is geared to apprenticeship and pre-apprenticeship training for new recruits. I am training my apprentice James by putting all of my knowledge online, in written and video form, so that he and anyone else who is interested can benefit. I just redesigned the home page to make it easier to find everything. Adding stuff almost everyday, just put up a new video this morning. If you have any young people who you think could get something useful out of the site, please pass it along. Check it out here: educatedclimber.com. Thanks again.
 
Another aspect of mechanical advantage, according to the angle of the dangle, comes down to when your system is applied with "advantage or dis-advantage".

Being the pulling source is run through either the anchor block or the moving block in the system. The latter is to the advantage, and the prior is to dis-advantage.

Which, when working with blocks, amounts to gaining or losing one leg in a pulling system. Again, it all comes down to the angle of the dangle. Yeow!
 
I have been following your site Mugg's and I think it is great!!!! I downloaded the knot book and still can't get over the fact that sailors so many years ago created these knots and systems out of necessity. Isn't there a saying the goes something like Necessity is the mother of invention. Or is it something else. Anyway great work when I first started I could have used something like your web site it would have helped allot. I have books and DVD's that I used when I started I they don't come cheap! I'm always open to learning something new or being reminded of the basics I can complicate the pudding out of something simple and if I go back to the basics the answer will come.
Ted
 
What always fascinated me about MA was the actual mechanism. How was a pulley amplifying the force? It wasn't until someone described the round sheave as a series of levers that it clicked for me. . . I love these various setups.

Do you have a source explaining this "pulley as lever" concept?
 
what made mechanical advantage click for me was switchbacks hiking up a mountain. If you spend a lot of time hiking up mountains it becomes clear the trade off that is made. You could choose to hike straight up the hill and walk less distance but wear yourself out very quickly or walk a longer distance with less energy.
 
Sean, it is kinda like the more parts of line, the longer the lever. You have to move the end of the lever much farther, but the force is greatly amplified. The trade-off is the distance vs force tho.
 
Very nice and needed, thanx! Really like your concept; as something i tired to achieve.
>>this is something i've turned many cartoons in head over and over on.
From a concentration that i had drawn in 90's to these internal images/and poems....
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There is no free ride; we are just redistributing the 2 force reciprocals in the mini ecosystem: power and distance to the same sum(total foot pounds of force) .
i think of it as running so much force x distance forwards or backwards thru a funnel
>>to concentrate(or dilute) the same power into a different distance.
>>For these models we ignore the tax of frictions at each conversion;
>>there is such a tax, no conversion is 100% (or Kennedy bullit would still be flying)
>>i mentally illustrate frictions tax as simply co$t of doing business with funnel/ what gets stuck to the sides
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Another model: i try to show volume of force as water in long aquarium; 1/5 full
>>with movable glass halfway that keeps the water on 1 side
>>as long as we input the same amount of water to start >> we have the same total force potential
>> we can move glass piece to concentrate water into smaller space and it rises/higher pressure onside
>> we can also move glass piece farther out to allow water cover more distance
>>>>at lower height/puts less pressure on glass sides!
>>another way to show in same model: water weight on bottom glass totally same, but different per square inch per movable glass
everything must be accounted for!
edit: Dad taught, as many; to eat all food/ don't waste some poor kid some place would really appreciate and it costs money!
>>i guess i taught same but with more weight: Physics says only so much energy
>>Something died or gave up it's young so you could eat; should be respectful enough to only take what you need; and not waste the sacrifice made!
(besides i'm a cheap SOB myself, so don't waste my money boy;and yeah there are people that are starving, should be grateful; is not any less!)
.

If We pull 20ft@100# pull we create 2000ft#'s we will always have this product output(or storage) from the reciprocals (minus tax)
We can take the 20ft@100# input into rigid or flexible 1st/2nd/3rd class lever systems,
>>and redistribute the reciprocals to concentrate or dilute power thru funnel to:
10ft@200#'s = 4ft@500#'s = 2ft@1000#'s = 50ft@40#'s = 2000ft#'s (each)
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Another assumption we make that Gerry points out is Zer0 deflection.
>>if each leg of rope is not 100% PURE inline it's cosine multiplier is less than 1 and the pulls are thus less
>>the volume of force in rope is not all pulling on pulley, some of it is pulling across on it's sine
>>cosine (inline) and sine(offset) are just 0-1 range multipliers of the potential force total on that leg
>>cosine of deflection just gives percentage of total force on that leg that is pulling on pulley to that target.
Even if in the .pdf tree pulls if say ropes in 2:1/3:1/5:1 rigs are PURE inline, if pulling @ 45degrees on target tree
>>getting only 70% of 2:1/3:1/5:1 rig as pulling across leveraged angle at the leveraged height on target tree.
>>those old Greek's were right, this is mostly geometry% of the potential input of distance X power
i think knot 'strengths' are defined by cosine, harder to get better than 70% knot 'strength'/efficiency
>>cuz 70% is kinda cosine of 45 degrees deflection, and cosine doesn't significantly change at this end of the bar
>>if we groom knot to only 30 degrees deflection/non-inline parts of rope we are only at 86% cos.
(i think of a rig as just an expanded view of forces inside of a knot;each are machines made with same materials,forces/subject to same rules!)
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But, each strategy that stands against Ye, a good gamer should be able to invert and capitalize on, to advantage
>>old worlde sweat/swig of line to grab more 'purchase' from load to control side does this, then 'hold fast' thru frictions
>>leveraged rope sine force that is usually working against you to weaken knots, pull sideways on tow hook
>>now gives leveraged effort against load w/o pulley frictions!!
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Counting the pulls on a compound pulley system must be done in layers, chase force thru multiple directions
>> focusing on the dynamic/ moving(power) rather than static(directional redirect only) pulleys (Beranek)
>>the compound system take a leg that usually would anchor/ground out , outside rig and fold that force back into rig for another pull!
>>this is accounting for force gets harder; essentially gives another force input point to chase power production/loss thru system
>>my 2 handing model essentially does that with your own body!
>>Then, used as compound pulley system w/2handing as another compounding input (another link)
>>i model this as using full 220v from fuse box, rather than just 1 leg of force 110v
>>i had used this for years in different ways, thought all were separate miracles.
>>but finally defined all as part of same model from our DdRT; were you pull yourself own self up with 2:1
>>>>both legs of line shorten 1ft. for you to rise 1ft.
>>can sift form from martial arts movies etc. too, our boy has been in and out of Akido for 15+ yrs.; he's an engineer now at citrus plant
For those that can deal with Flash dep(h)recating in 2020 mytreelessons.com/Flash/pulley21xRig.swf
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CoG of tree distance/angle from compressed part of hinge pivot is the load leverage
>>stretched fibers in hinge distance/angle from pivot is the support leverage
>>these/everything are in balance OR moves until balance is achieved;
>>the motion itself making up the imbalance.
So the tree falls, until is satiated/exhausted by meating it's Equal and Opposite
>>same as electricity, people etc.!
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Points might seem scattered,but to me are all pivotally the same!
'Exactly the same; but different' my buddy used to say.
If you can stretch to see that; every time you see one in action, you L-earn/confirm about all..
Another exercise/stretch is to be able to trace all powers backwards thru systems,
>>also trace not only the compounding of forces, but also compounding of inefficiencies
>>as much for understanding as for checksum of what you think you see!
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Merry Christmas!
 
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