Designing a Pulley System to Increase Weightlifting Force

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Monkey
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Hi,

I am building a simple pulley for a weightlifting machine. In most cases pulleys are designed to lift heavier loads easier, I want to actually make it harder to lift the load… So I don't have to put so much weight on the end.

Can I amend my simple pulley design in a (simple) way to increase the force required to lift the load at the end?

In my example I want to lift the 50kg load… How would I make it double the load, so it feels like I am lifting 100kg?
 

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Look at schemes that make a weight easier to lift and interchange the person pulling with the weight being lifted.

For example, end of rope attached to ceiling. Rope goes under a movable pulley attached to pull-handle and then over a pulley attached to the ceiling and then to a weight attached to the other end of the rope.
 
For instance, look at the drawing
 

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Thank-you very much for your replies. Have got a few ideas in mind now about how to make it work.

Best regards.