School Project with crossbow got shot down
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School Project with crossbow got shot down
Our class had a few topics assigned to a few people each. Mine was "Leverage". We're supposed to demonstrate the topic with some sort of model. I made a sort of crossbow out of a piece of raton with a bow string mounted to a board. I showed how hard it was to "cock" the string by hand. Then I showed how it was easier with the Excalibur cocking rope. Then it was even easier with the Dr Stirrup 4X4 Kocker. Last, I put a ratchet strap on it and hooked the strap to my bowstring and cranked it up. The teacher rambled on about fulcrums and multipliers and transfer of work something whatever whatever. She said that was not leverage. I said I think a person with a crossbow has a lot of leverage. She didn't think that was funny either. I have to do the project over
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Re: School Project with crossbow got shot down
Tough dealing with “snowflake” teachers these days, huh?
I would have given you an excellent!
I would have given you an excellent!
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Re: School Project with crossbow got shot down
X2! Hard to prove a teacher wrong, especially when they know everything.
It’s not the way you rock, it’s the way that you roll!
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Re: School Project with crossbow got shot down
Leverage
noun
- the action of a lever, a rigid bar that pivots about one point and that is used to move an object at a second point by a force applied at a third.
- the mechanical advantage or power gained by using a lever.
Dam teachers what do they know
I guess one could conclude another fact in that you
failed on two counts
"to also demonstrate the other definition of leverage as well.
"power or ability to act or to influence people, events, decisions, etc.; sway:"
A Double Whammy.
I would say you should count your lucky stars you get to do a "do over".
noun
- the action of a lever, a rigid bar that pivots about one point and that is used to move an object at a second point by a force applied at a third.
- the mechanical advantage or power gained by using a lever.
Dam teachers what do they know
I guess one could conclude another fact in that you
failed on two counts
"to also demonstrate the other definition of leverage as well.
"power or ability to act or to influence people, events, decisions, etc.; sway:"
A Double Whammy.
I would say you should count your lucky stars you get to do a "do over".
Re: School Project with crossbow got shot down
Levers, and ropes and pulleys are examples of mechanical advantage.
However, your demonstration did offer one example of leverage....your ratchet strap uses leverage to advance the ratchet, the fulcrum is the pin the lever turns on.
Just remember, when you point out to people how they are in error, do it in such a way that you don't appear to be trying to demonstrate how clever you are and how stupid they are.
However, your demonstration did offer one example of leverage....your ratchet strap uses leverage to advance the ratchet, the fulcrum is the pin the lever turns on.
Just remember, when you point out to people how they are in error, do it in such a way that you don't appear to be trying to demonstrate how clever you are and how stupid they are.
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Re: School Project with crossbow got shot down
I found the smartass comment funny. Your teacher has no sense of humor. You came close XB, but technically your teacher was right. You might have to dum it down and go with accepted examples. I do like your ideas though.
Hank
Hank
Re: School Project with crossbow got shot down
Check out the goats foot lever and the gaffe lever. Both were used to help cock medieval style crossbows. The gaffe lever is a bit easier to build than the goats foot lever.
https://todsworkshop.com/blogs/blog/crossbows-spanning-methods
https://todsworkshop.com/blogs/blog/crossbows-spanning-methods
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Varizone with Burris Sig. Zee Rings
My mods:
Scope cover adapters
Optomechanical rangefinder
Custom built lit nocks
BCY Trophy flemish string
20" XX75 2219 arrows with 4" feathers
Re: School Project with crossbow got shot down
Your trigger is an example of a lever/fulcrum.
Some people just like stepping on rakes
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Re: School Project with crossbow got shot down
Poor ol' blue collar carpenters leverage lesson..... Hit it with your hammer... if it doesn't move, hit it harder...if it still doesn't move get a bigger hammer...a sledge can be yo friend! ( lesson #2...don't let poor ol' blue collar carpenters get you in dutch with your teachers! or your folks!)
Re: School Project with crossbow got shot down
Just tell the teacher that you saw them in the lounge being cozy with another teacher, and if you don't get an A+ you will tell her husband, now that's leverage!
Seriously, if you could make up some type of cocking device using the fulcrum principle of leverage, I think the project would possibly pass. Maybe could use multiple sheave pullies on a cocking device, that should fit the criteria of a multiplier.
I don't want you to get an F, maybe better to move on to plan B and not listen to me!
Seriously, if you could make up some type of cocking device using the fulcrum principle of leverage, I think the project would possibly pass. Maybe could use multiple sheave pullies on a cocking device, that should fit the criteria of a multiplier.
I don't want you to get an F, maybe better to move on to plan B and not listen to me!
Re: School Project with crossbow got shot down
Shaffern has a great suggestion!
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Re: School Project with crossbow got shot down
Shafferm is a very smart engineer XB. Pick his brain he will not disappoint .
He has a very good example of levers .
He has a very good example of levers .
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Re: School Project with crossbow got shot down
Boo’s idea of trigger is good too. You can prove leverage with a trigger pull gauge at different points along the length of trigger.