Tackles

Question 1

What is a purchase

Answer 1

Combination of blocks/pulleys rove with a rope, wire, chain

Question 2

What is a tackle

Answer 2

A purchase consisting of rope rove pulled through 2 or more blocks.

Question 3

What is a fall

Answer 3

Whole rope used in a purchase. Size of tackle is described by size of fall

Question 4

Mechanical Advantage

Answer 4

Disparity between amount of force required to move an object and the weight of an object

Question 5

How do you calculate the MC

Answer 5

Divide the weight of the object being lifted by the force required to lift it.

Ie divide 200lb crate by force required to lift it ie 2

Question 6

What is friction

Answer 6

When an object moves against another, some moving objects energy is lost to friction. (Can reduce mechanical advantage)

Question 7

What is reeving

Answer 7

Is how a block and tackle are set up together - either reeved at advantage or disadvantage

Question 8

When is a tackle reeved at a advantage

Answer 8

It is reeved at an advantage when the rope is being pulled in the same direction that the load is being pulled. Ie away from standing block

Question 9

When is a tackle reeved at disadvantage

Answer 9

When the rope is being pulled in the opposite direction that the load is moving

Question 9

Describe single whip tackle

Answer 9

One single sheave block, fixed to a support, with rope passing over sheave

Question 10

What is MC of single whip tackle

Answer 10

1, no mechanical Advantage is gained

Question 11

Describe a runner tackle

Answer 11

Consists of a rope rove through a single moving block, 2 parts of fall

Question 12

Advantage of a runner tackle

Answer 12

2

Question 13

Describe a double whip tackle

Answer 13

Simplest form of purchase - fall is rove through 2 single blocks. Standing is secured to upper block

Question 14

Another name for double whip tackle

Answer 14

Gun tackle

Question 15

MC of double whip tackle

Answer 15

3, if disadvantage 2

Question 16

Describe Luff tackle

Answer 16

A purchase of 75mm or greater. Consists of a double & single block. Standing part of fall made fast to single block

Question 17

MC of LUFF

Answer 17

3 or 4

Question 18

Describe a Jigger tackle

Answer 18

50mm (similar to luff/double & single block) though there is a tail on the double block instead of hook. Standing part of fall is spliced to single block

Question 19

Describe a handy billy tackle

Answer 19

Similar to luff tackle but smaller the 50mm (one single and double blocks)

Question 20

Describe a 2 fold purchase

Answer 20

2 double blocks, commonly used to hoist boats

Question 21

MC advantage of 2 fold purchase

Answer 21

4 or 5

Question 22

Describe a 3 fold purchase

Answer 22

2 triple blocks

Question 23

MC of 3 fold purchase

Answer 23

6 or 7

Question 24

What does it mean to overhaul a tackle

Answer 24

To separate the block further from each other

Question 25

What does it mean to round up a tackle

Answer 25

To move blocks closer together