Extreme Block and Tackle: Building Manual Winch with 4:1 to 500:1 Ratios

  • Thread starter DaveC426913
  • Start date
  • Tags
    Block
In summary, Extreme Block and Tackle is a manual winch that allows for ratios of 4:1 to 500:1. This innovative tool makes it easier to lift and move heavy objects by using a system of pulleys and ropes to distribute the weight. With its high ratios, the Extreme Block and Tackle can handle a wide range of load sizes and can be used in various industries such as construction, agriculture, and transportation. Its compact and durable design also makes it a versatile and reliable tool for any heavy lifting needs.
  • #1
DaveC426913
Gold Member
22,497
6,168
[ backstory ]
Yesterday I finally, and sadly, put my Matilda http://davesbrain.livejournal.com/315479.html" to bed for the winter.

I want to lift her off her trailer so I can work on her hull. She's 1500lbs. The barn she's sleeping in has a massive traveling lift system (18" steel I-beam on a track) but no winch.

I can't afford to rent a winch for the whole time I have it hanging. (Yes, I know I can build a cradle to sit her on, but...) So I've been thinking about building a manual winch using block & tackle.
[ /backstory ]

So I started wondering how big a block & tackle system I'd need. A rope with 1500lb test?

Question 1 : Correct me if I'm wrong: for a block & tackle with, say 4:1, my line's strength need only be 1500/4=375lbs, right?

What if my block & tackle were 100:1? I'd only need a line that could support 15lbs.
I know that 100 pulleys may sound like a lot but each wheel would only have to support 15lbs. so they could be compact.

What if I had 500:1? 3lb test line. I could lift my boat off its trailer with sewing thread tied to my pinkie!

(Of course, to lift it a mere foot, I'd have to run a tenth of a mile away!)

Question 2 : Is there a flaw in my logic?

I'm thinking the friction might do me in, but I'm also thinking that the friction would be distributed among the 500 strands so it shouldn't be a problem. Or is the friction cumulative?
 
Last edited by a moderator:
Physics news on Phys.org
  • #3
Bob S said:
Get a comealong:
http://www.cvfsupplycompany.com/hanpowpulcom.html
Really. :bugeye:

That little <$100 device will allow me to hand winch my boat into the air. Wow.

Thank you.

Then my next question is going to be how to design the cradle so that it supports and balances the boat.
 
  • #4
Unless you can get a cradle that has the pivot point above the boat's center of gravity, I suggest two comealongs, or two straps lifting the boat tied to a crossbeam.
Bob S
 
Last edited:

What is "Extreme Block and Tackle: Building Manual Winch with 4:1 to 500:1 Ratios"?

"Extreme Block and Tackle: Building Manual Winch with 4:1 to 500:1 Ratios" is a type of mechanical system that uses multiple pulleys and ropes to create a powerful lifting or pulling mechanism. It can achieve a wide range of ratios, from 4:1 to 500:1, depending on the number of pulleys used.

How does a block and tackle system work?

A block and tackle system works by distributing the weight of an object over multiple ropes and pulleys. The more pulleys used, the easier it is to lift or pull the object, but the distance the rope must be pulled is also increased. This allows for a greater mechanical advantage and makes it easier to lift heavy loads.

What are the advantages of using a block and tackle system?

There are several advantages to using a block and tackle system, including increased lifting capacity, reduced effort needed to lift heavy objects, and the ability to achieve a wide range of ratios. It is also a relatively simple and cost-effective solution for lifting and pulling tasks.

What are some common applications of "Extreme Block and Tackle" systems?

Extreme Block and Tackle systems can be used in a variety of industries and settings, including construction, shipping and transportation, manufacturing, and agriculture. They are especially useful for tasks that require heavy lifting or pulling, such as hoisting materials or moving large objects.

Are there any safety considerations when using a block and tackle system?

Yes, there are several safety considerations to keep in mind when using a block and tackle system. It is important to properly secure the system and its components, carefully calculate the load and ratios, and regularly inspect and maintain the system to ensure safe operation. It is also crucial to follow proper lifting and pulling techniques to prevent injury.

Similar threads

Automotive Maximizing MPG in a 1973 Ford 200 Inline 6-Cyl for a 65 Mustang
    • Mechanical Engineering
Replies
9
Views
2K
Building a Counter with IR Sensor and Manual Buttons
    • Electrical Engineering
Replies
6
Views
2K
Model Pulley: Understanding System Physics
    • General Engineering
Replies
27
Views
8K
Chemistry 35yo combustion chemistry PhD, free time and still no plan
    • STEM Career Guidance
Replies
4
Views
1K

Hot Threads

Recent Insights

Back
Top