Super useful video. And thanks for showing that the distance doesn't change when the diameters are the same - I figured, but but the curiosity in me just _needed_ to see that it actually worked that way.
A very interesting little demo - I often looked for some "mechanism" that could prevent the danger from the fast spinning handle when just leaving the hoist - and here it is ... and it's been there for generations, I think !
Mr. Pete, thank you for uploading that video. as humdrum as i thought it might be initially, it turned out to be one of your more informative and interesting videos yet. i can't wait to see the one on chain hoists. the kids of illinois lost one of their finest teachers when you retired. but the world of youtube has gained a great one! cheers mike
This is a terrific explanation for an ingenious machine. I first watched #7 (the Differential Hoist) and did not fully understand why it worked. But after watching this . . . wow! You've performed a great service by posting this and so many other presentations. And I have now subscribed to your channel.
I can't believe I've never heard of this, or I have and just forgot like everything else. Either way, this was an awesome demonstration and incredibly informative
That's a mechanism I've not seen before ! I've seen 'like' it - where the rope being pulled is wrapped around a larger drum than another rope attached to the load - so similar mechanical advantage system but I'd not seen one where the rope goes to the load and comes back to a different sized drum. There is a variant concept used in some spring-driven clocks. on the shaft the spring acts on is a conical threaded pulley and wrapped around it is a 'rope' (possibly wire) the other end of which is wound onto another conical threaded pulley. The concept being, as the spring unwinds, it gets weaker - so the clock would slow. Via the rope between the conical threaded pulleys, as the spring unwinds and gets weaker the conical pulleys alter the mechanical advantage increasing the relative force on the second pulley to counteract the weaker force being applied to the first one. The cone angles would be the same and an angle chosen depending on how fast the spring loses its strength as it unwinds.
Great demo unit. As you say this would be excellent to show kids. I am looking forward to the chain winch vid. I never stopped to think how they work, but now you got me thinking. Thanks Mr Pete!
I think you like teaching and spreading your knowledge. And what wonderful knowledge it is even to this old 70 year old man. I always learn something new. Love the videos. Mike
that was good,, really enjoyed it !! for got to tell ya that i enjoyed the blacksmith trip as well !! My grandpa was a tool and die man for about 45yrs,, i cut my 1st 1/2-13 thread in his shop when i was 12yrs old in the early 80's so when i see the old tools it sometimes takes me back to the time when i was around his belt-driven south bend lathe and his bridgeport with optics,, he never used a DRO and oh how i wish i could show him the solid-modeling and CAM wares i use now but doin it all by hand has always been my favorite,, i suppose thats because conventional was all i did until 17yrs ago,, hated CNC at 1st,, i dont think grandpa would like CNC work,, i think he would feel that it took away the "true skill" of making and polishing a mold,, anyway love the videos,, keep'em coming,, thanks
Thank you, Mr.Pete. I always learn something new, watching your videos. I have heard of a windlass but, not the Chinese one nor how it worked. Facinating!
I've always loved the chinese windlass because it gives such a great mechanical advantage with crude materials. I imagine building one from a log carved down a bit on one end. something that could be done with a hatchet by anyone.
you have a fantastic knowledge, I am a retired engineer and I have never seen this before I wish we could get back to teaching our kids the basics of how the world works,please keep up the vids you are filling in the gaps in my education
My gosh, you've explained this so well and demonstrated it so clearly! Thank you! I've no exposure to mechanical machines like this despite being interested in how they work so cleverly 😅 When you were showing what happens if the radii were both the same, my head went PI(0)=0, but intuitively your demonstration showed that the same length down and up results in no movement It also made me think about how a normal snow white hoist is just the smaller wheel having 0 radius - but that's technically a single pulley system with 2:1 advantage Which made me realise We use radius here to calculate because the length of the string for one revolution is pi*diameter (2pi*r) But the rope loops back up so the distance is split in half Also it made me realise: this is like having a hoist with a very very very tiny radius. Which is like a small gear turning a big one Oh gosh it's all linking!
Ive been wondering what would happen when there was 0 differential, but I couldnt picture it, having not yet built a model to experiment with. Seeing it "not work" made me to finally internalize how it does work. Thanks!
It is interesting to note that the important parameter is the *difference* between the two radii. So the example (at 6 minutes) with R = 0.625" and r' = 0.375" would function precisely the same (ignoring dynamics such as inertia, etc.) if both radii were 100" larger. ie, R = 100.625" and r' = 100.375". Of course, with such large radii, a correspondingly large amount of string would be whizzing through the pulley supporting the bucket load.+++++++++++++++++Mr. Pete - A differential thread is somewhat related. Perhaps you could add an episode to go there, too.Approaching the differential hoist from first considering the differential windlass is a brilliant teaching tactic. Good Job! Besides being a master craftsman, you are also a master teacher. I appreciate the passion you bring to producing these videos. In 30 years, I expect most of your videos will still be relevant and regularly referenced.Thanks!!
Excellent series mrpete. Great explanation of the Chinese Windlass. I did notice the shaft with the central stop to prevent the rope crossing onto the adjacent diameter although you did not mention it. Thanks for sharing. regards from the UK
Protagonist of new Paulette Giles book is fixing the “differential windlass” on a confederate war-widow’s farm well. The horses were thirsty. Books lead to interesting places, don’t they? Enjoyed the video. Thank you.
Thing is you need to be encouraged. I share your vids with my kids. When folks start to learn about simple machines and practical knowledge it inspires them to do and learn more. Keep it up and stay safe.
Slowish progress of late with other work projects I have been involved with. I am well underway with machining the cylinders however. The videos will be emerging soon.
Wow, that is slickern snot on a glass door knob. Hey, I was going to ask what happens if both sides are equal, but it seems that is obvious to most viewers. At 77 I guess those brain cells went in to hold status. Thanks for this truly great video.
That is cool. I've know about it for some time. Have intended to make one, but never did. Now I think I will. Should make a good item to put on an office desk and watch everyone that comes in play with it. :)
the weight does not fall because the push and the pull are balanced with ropes either side of the weight. imagine there are two persons either side of the weight at the height of the axle/shaft. one letting go of the rope and the other pulling towards himself ... if both do apply same tension then weight does not move ... but pulley revolves freely... if one man does not let go freely, holds slightly tight while the other person pulls slightly hard, then the load slightly moves proportional to difference between push and pull. Ways of getting mechanical advantage is chain hoist(gears + differential) or using counter weight
+mrpete222 ... I like to study old New England barns. I've seen large wooden wheels up in the beams of the loft. I think this system was used to lift a loaded wagon up to the peak, so hay could be thrown off to fill the barn higher. An old barn @ Sturbridge had some of this setup, and they didn't know what it was for.
I have seen on our our farm in Finland that a large pole is used to lift a bucket of water from the well....what this is called I do not know but perhaps you might know....thanks for a nice demo.
Thanks a lot, especially for including the formula! Could you please provide the formula for the work you shall use for a certain weight with different sized shaft and handle length?
Tubalcain, great explanation on these fascinating hoists. I wanted to share a question I have with you. Since the increased number of cranks at the shaft seems to be the drawback of this system what would happen if you installed a smaller pulley to the crank shaft mated by chain drive to a larger drive pulley. Similar to how the gears on a bike are tuned to increase the speed of the rear wheel. Thus should increasing the crankshaft RPM while allowing for same handcrank input rpm and hoisting the load quicker. I imagine the input force (torque) demand would increase at the input shaft but in certain configurations it may be effective. Do you agree with this idea or do you think this would not work, and why?
You would benefit from increased speed, but lose out to input force. It would be possible to calculate the speed advantage and the force increase. However compared to an equivalent simple windlass (as per the start of the video) your system would have more losses and would require more effort. But, and this is one great feature of the Chinese windlass is that it won't unwind when you let go, your system would keep this.
I've wondered if accurate wooden jack screws could be made without gears, using this mechanism . Mount the Chinese windlass on the spindle of a simple lathe. Use a pulley wheel to change the direction of pull to be parallel to the spindle. A free hanging weight would keep the string taught, and a saddle can then be pulled back and forth.
It takes a stroke of genius to make such an effective, simple machine.
I used a chain hoist 75 years ago. Now I know how it worked. Thanks for demonstrating this.
Wow! It's rare that I come across an unfamiliar mechanical concept, but this was certainly one. I really enjoyed learning something new- Thanks!
+componenx THANKS for watching--much more to come
Very interesting. Thanks for showing this.
+Applied Science THANKS for watching
Super useful video. And thanks for showing that the distance doesn't change when the diameters are the same - I figured, but but the curiosity in me just _needed_ to see that it actually worked that way.
I've waited exactly 27 yrs & 8 months to see a vid,,,, like this.... :) YAY ! GOOD !
A very interesting little demo - I often looked for some "mechanism" that could prevent the danger from the fast spinning handle when just leaving the hoist - and here it is ... and it's been there for generations, I think !
+Keld Sørensen THANKS for watching
What a great invention and the fact that it doesn't slip or drop is a mind bender. thanks.
+SonsOfTesla.Com Thanks for watching
Mr. Pete,
thank you for uploading that video. as humdrum as i thought it might be initially, it turned out to be one of your more informative and interesting videos yet. i can't wait to see the one on chain hoists.
the kids of illinois lost one of their finest teachers when you retired. but the world of youtube has gained a great one!
cheers
mike
+HolzMichel Thank you so much!!
mrpete222 sir. can i need an explanation why the weights don't drop if the crank is released? i'm doing this as my project.
This is a terrific explanation for an ingenious machine. I first watched #7 (the Differential Hoist) and did not fully understand why it worked. But after watching this . . . wow!
You've performed a great service by posting this and so many other presentations. And I have now subscribed to your channel.
Very interesting Mr. Pete, I hadn't heard of this before. Simple and ingenious at the same time.
+ShysterLawyer THANKS for watching
Mrpete222 I think you are the world’s most interesting grandpa (not to mention the best shop teacher ever.) Your grandkids are super lucky!
Thank you very much
I can't believe I've never heard of this, or I have and just forgot like everything else. Either way, this was an awesome demonstration and incredibly informative
Thanks
That's a mechanism I've not seen before !
I've seen 'like' it - where the rope being pulled is wrapped around a larger drum than another rope attached to the load - so similar mechanical advantage system but I'd not seen one where the rope goes to the load and comes back to a different sized drum.
There is a variant concept used in some spring-driven clocks. on the shaft the spring acts on is a conical threaded pulley and wrapped around it is a 'rope' (possibly wire) the other end of which is wound onto another conical threaded pulley. The concept being, as the spring unwinds, it gets weaker - so the clock would slow. Via the rope between the conical threaded pulleys, as the spring unwinds and gets weaker the conical pulleys alter the mechanical advantage increasing the relative force on the second pulley to counteract the weaker force being applied to the first one. The cone angles would be the same and an angle chosen depending on how fast the spring loses its strength as it unwinds.
Great demo unit. As you say this would be excellent to show kids. I am looking forward to the chain winch vid. I never stopped to think how they work, but now you got me thinking. Thanks Mr Pete!
+Rupert Powell Thanks for watching
I think you like teaching and spreading your knowledge.
And what wonderful knowledge it is even to this old 70 year old man.
I always learn something new.
Love the videos.
Mike
+Oldvet1946 THANKS for watching!
that was good,, really enjoyed it !! for got to tell ya that i enjoyed the blacksmith trip as well !! My grandpa was a tool and die man for about 45yrs,, i cut my 1st 1/2-13 thread in his shop when i was 12yrs old in the early 80's so when i see the old tools it sometimes takes me back to the time when i was around his belt-driven south bend lathe and his bridgeport with optics,, he never used a DRO and oh how i wish i could show him the solid-modeling and CAM wares i use now but doin it all by hand has always been my favorite,, i suppose thats because conventional was all i did until 17yrs ago,, hated CNC at 1st,, i dont think grandpa would like CNC work,, i think he would feel that it took away the "true skill" of making and polishing a mold,, anyway love the videos,, keep'em coming,, thanks
+ALUMATRIX Glad you liked the black smith shop THANKS for watching!
Thank you, Mr.Pete. I always learn something new, watching your videos. I have heard of a windlass but, not the Chinese one nor how it worked. Facinating!
+Dave Lee THANKS for watching
I've always loved the chinese windlass because it gives such a great mechanical advantage with crude materials. I imagine building one from a log carved down a bit on one end. something that could be done with a hatchet by anyone.
+tinkersdamnworkshop THANKS for watching--much more to come
you have a fantastic knowledge, I am a retired engineer and I have never seen this before I wish we could get back to teaching our kids the basics of how the world works,please keep up the vids you are filling in the gaps in my education
+Steve Dunger THANKS for watching
This is a "Two Thumbs Up" video! Mechanical advantage in a way that I had never imagined. Thanks for another great educational video.
+jrcraft1 THANKS for watching!
Awesome! I have never seen this demonstrated. Great video and explanation of the forces at work.
+Brandon Lund THANKS for watching
My gosh, you've explained this so well and demonstrated it so clearly! Thank you!
I've no exposure to mechanical machines like this despite being interested in how they work so cleverly
😅 When you were showing what happens if the radii were both the same, my head went PI(0)=0, but intuitively your demonstration showed that the same length down and up results in no movement
It also made me think about how a normal snow white hoist is just the smaller wheel having 0 radius - but that's technically a single pulley system with 2:1 advantage
Which made me realise
We use radius here to calculate because the length of the string for one revolution is pi*diameter (2pi*r)
But the rope loops back up so the distance is split in half
Also it made me realise: this is like having a hoist with a very very very tiny radius.
Which is like a small gear turning a big one
Oh gosh it's all linking!
👍👍👍👍
Marvellous, never seen or heard about such a device. Thanks for putting up this excellent demonstration video.
+Dan Whiteford THANKS for watching
Ive been wondering what would happen when there was 0 differential, but I couldnt picture it, having not yet built a model to experiment with. Seeing it "not work" made me to finally internalize how it does work. Thanks!
Fabulous, such a beautiful principle so clearly explained; your clear clutter free back grounds so help to focus attention.
+Springwood Cottage THANKS for watching--much more to come
Very interesting and informative. The concept is so simple yet ingenious and no need for batteries or remote control.
+PGS Thanks for watching
A great example of low-tech genius design. Just the way I like it.
+Nico Smets THANKS for watching!
Fascinating!!
I must get me a differential hoist for my garage. That’s a great video also.
My grandchildren will love it!!! thanks!!
+Jeff Conti THANKS for watching--much more to come
something we rarely think about. thanks for the time making this.
+Lee Waterman THANKS for watching
Now that's pretty neat. I'm impressed that big TH-cam channels like Applied Science and AvE comment here too. You're too good to us Mr Peterson
+1musicsearcher THANKS for watching--much more to come
Thank you again! Wonderful demonstration of a simple but powerful device.
+Metallurg33 THANKS for watching
It is interesting to note that the important parameter is the *difference* between the two radii. So the example (at 6 minutes) with R = 0.625" and r' = 0.375" would function precisely the same (ignoring dynamics such as inertia, etc.) if both radii were 100" larger. ie, R = 100.625" and r' = 100.375". Of course, with such large radii, a correspondingly large amount of string would be whizzing through the pulley supporting the bucket load.+++++++++++++++++Mr. Pete - A differential thread is somewhat related. Perhaps you could add an episode to go there, too.Approaching the differential hoist from first considering the differential windlass is a brilliant teaching tactic. Good Job! Besides being a master craftsman, you are also a master teacher. I appreciate the passion you bring to producing these videos. In 30 years, I expect most of your videos will still be relevant and regularly referenced.Thanks!!
+Dave Kellogg THANKS for watching--much more to come
Excellent series mrpete. Great explanation of the Chinese Windlass. I did notice the shaft with the central stop to prevent the rope crossing onto the adjacent diameter although you did not mention it. Thanks for sharing. regards from the UK
+Gary C THANKS for watching
Ah-ha! Brilliant. I always wondered how chain hoists work their magic, and now it's obvious. Thanks, Mr. Pete.
+FXM THANKS for watching!
Lyle, another good one, as per usual !!! Please, always keep em coming. Your friend, Cliff
+Clifford Fender THANKS for watching!
You got my vote for this as most interesting and educational video demonstrating something so simple, and, surprisingly, so unknown... Pierre
+pierre beaudry Thanks for all your wonderful comments & support--THANKS for watching!
My pleasure... You deserve all of the best... ;)
Thanks, I had seen this before but had forgotten about it completely. It may come in handy in the future.
+Doug Hibberd THANKS for watching--much more to come
Awesome. I love it. Thank you.
Brilliant Lyle. Thanks once again. From sunny Wales
+Dave Jones THANKS for watching
Thanks Mr.Pete! Very cool
+ckvasnic1 Thanks for watching
I enjoy all your videos. Thanks, and please keep them coming!
+Pat Sullivan THANKS for watching
i must have lived a sheltered life that is the first time i have ever seen one of those.. thank you sir for sharing..
+Kevin Willis THANKS for watching
Protagonist of new Paulette Giles book is fixing the “differential windlass” on a confederate war-widow’s farm well. The horses were thirsty. Books lead to interesting places, don’t they? Enjoyed the video. Thank you.
👍👍
Thank you Mr. Pete. I really like this series.
+Rob Robinson THANKS for watching--much more to come
I love this series. Thank you.
+John Strange THANKS for watching
As always excellent video. Keep them coming.
+just tim THANKS for watching!
Thanks for the interesting and informative video Lyle. Please keep them coming.
+Tom Bellus THANKS for watching
Excellent and informative as usual. Thanks,
+Darren Martin THANKS for watching
Mr. Pete makes learning fun!
+lumspond THANKS for watching--much more to come
Hmmmmm, he says eying out stuff to apply this concept to. Thanks Mr Pete, informative as ever.
+stevedotrsa THANKS for watching--much more to come
i love it. I learned something here. I never knew such a machine. Thanks.
once again you continue to inspire. I Thank You for sharing.
+Ashley Ward (Ash) THANKS for watching--much more to come
Always a thumbs up for your vids educational not like the school i was in What a bad school it was thanks for the time you put into the videos
+drz400smk7 THANKS for watching
Well done. You really do a great job. You are truly an educator!
Thank you very much, that is encouraging
Thing is you need to be encouraged. I share your vids with my kids. When folks start to learn about simple machines and practical knowledge it inspires them to do and learn more. Keep it up and stay safe.
Thanks for wonderful explanation. Loved it.
👍
Brilliant series of videos.
+Mr-Laing Thanks for watching-
Very interesting, i never seen this before looking forward to see what you have installed next.
+one4stevo THANKS for watching!
Thanks for showing the math behind it, great information.
Fascinating. Thank you.
+MrSpinteractive THANKS for watching--much more to come
I like it! Very interesting. I always look forward to, and enjoy this series Mr. Pete. Thanks!
+MrGoosePit THANKS for watching
Great video, I am enjoying the series.
+MrCrispin96 Hows the engine coming along---THANKS for watching!
Slowish progress of late with other work projects I have been involved with. I am well underway with machining the cylinders however. The videos will be emerging soon.
Good Job Mr. Pete was enjoyed .Thank You !
+Gene Fultz THANKS for watching
Awesome! Thanks for sharing. You are a great and wise teacher.
+GunPilot THANKS for watching
Live and learn. Great video, thanks for sharing.
+Stanwood Dave THANKS for watching
Thanks Mr Pete, great info, did not know this!
+Tim Ambrass THANKS for watching--much more to come
Super interesting! 👍
Thumbs up Mr. Pete! Now I don't have to disassemble my chain hoist to figure it out.
+Rick Rose THANKS for watching!--watch the next one on the chain hoist
That's some sneaky use for shop tooling. Cool demo.
+Vantss THANKS for watching--much more to come
A superb explanation.
I will use this for the well I have on my farm....
Thank-you
+68sweetnovember THANKS for watching--much more to come
I love these little bits of information looking forward to using this applied sciencethanks
+Simon Stack Thanks
Wow, that is slickern snot on a glass door knob. Hey, I was going to ask what happens if both sides are equal, but it seems that is obvious to most viewers. At 77 I guess those brain cells went in to hold status. Thanks for this truly great video.
+Kenneth Bartlett THANKS for watching
This is very much like the differential pulley.
edit, Haha, I see you mentioned it at the end. Great video.
+ExtantFrodo2 yes-THANKS for watching!
very cool!! never seen this until now. Thanks for the video.
+themadmailler Thanks for watching
Very interesting. Thank you very much !
Thanks
That is cool. I've know about it for some time. Have intended to make one, but never did. Now I think I will. Should make a good item to put on an office desk and watch everyone that comes in play with it. :)
+DSCKy THANKS for watching--much more to come
Yes, I agree, "Rather a neat phenomenon".
Good video. Thanks for making it.
Pretty neat stuff! I bet your grandson Jordan will like learning about this hands on! Chris
+shadowdog500 THANKS for watching!
Very good explanation. Thanks.
+RP Mechanics THANKS for watching--much more to come
Thanks for the wisdom. Thanks for sharing
+sam yeates THANKS for watching
Fascinating!!
+Watcher Johnny THANKS for watching--much more to come
the weight does not fall because the push and the pull are balanced with ropes either side of the weight.
imagine there are two persons either side of the weight at the height of the axle/shaft. one letting go of the rope and the other pulling towards himself ...
if both do apply same tension then weight does not move ... but pulley revolves freely...
if one man does not let go freely, holds slightly tight while the other person pulls slightly hard, then the load
slightly moves proportional to difference between push and pull.
Ways of getting mechanical advantage is chain hoist(gears + differential) or using counter weight
Thank you for shsring, I learnt something new today
thank you mrpete222 very cool video
+stevenacarter77 THANKS for watching--much more to come
+mrpete222 ... I like to study old New England barns. I've seen large wooden wheels up in the beams of the loft. I think this system was used to lift a loaded wagon up to the peak, so hay could be thrown off to fill the barn higher. An old barn @ Sturbridge had some of this setup, and they didn't know what it was for.
The hoist on a job site is called a well wheel, but there is no crank. The rope goes to the ground and a worker hauls the load up from there.
+Paul Frederick Thats neat--THANKS for watching!
I have seen on our our farm in Finland that a large pole is used to lift a bucket of water from the well....what this is called I do not know but perhaps you might know....thanks for a nice demo.
Thanks a lot, especially for including the formula! Could you please provide the formula for the work you shall use for a certain weight with different sized shaft and handle length?
mr. pete. very cool video. keep them coming! :)
+Randy Stuart THANKS for watching--much more to come
That's a great video. Can you give the name of the book you found that in? I'm hoping I can find a digital version of it. Thank you.
That is a new one on me. I'll have to build a small scale model of it so I can copy it at full size when I really need one.
+dan andy Thanks for watching
Very interesting!
Very cool never seen one of those before.
+JWB671 THANKS for watching--much more to come
i liked it. good learning tool .
+commando340 THANKS for watching--much more to come
incredibly interesting!! thank you!!
Tubalcain, great explanation on these fascinating hoists. I wanted to share a question I have with you. Since the increased number of cranks at the shaft seems to be the drawback of this system what would happen if you installed a smaller pulley to the crank shaft mated by chain drive to a larger drive pulley. Similar to how the gears on a bike are tuned to increase the speed of the rear wheel. Thus should increasing the crankshaft RPM while allowing for same handcrank input rpm and hoisting the load quicker. I imagine the input force (torque) demand would increase at the input shaft but in certain configurations it may be effective. Do you agree with this idea or do you think this would not work, and why?
You would benefit from increased speed, but lose out to input force.
It would be possible to calculate the speed advantage and the force increase.
However compared to an equivalent simple windlass (as per the start of the video) your system would have more losses and would require more effort.
But, and this is one great feature of the Chinese windlass is that it won't unwind when you let go, your system would keep this.
Thats pretty neat Mr. Peterson
+bigjohnypoper THANKS for watching
Pretty cool, filed away for future reference. Thanks!
+Cuppa Joe THANKS for watching--much more to come
I've wondered if accurate wooden jack screws could be made without gears, using this mechanism . Mount the Chinese windlass on the spindle of a simple lathe. Use a pulley wheel to change the direction of pull to be parallel to the spindle. A free hanging weight would keep the string taught, and a saddle can then be pulled back and forth.
+steve cummins THANKS for watching--much more to come