Design of levers ?

[waterworks178]

I'm looking at coming up with a design for a press to produce biomass fuel brickettes, these will be made of reeds that are cleared from a local waterway and are in unlimited free supply, if this could be done manually without a hydraulic pump it would be really cost effecient , this process of disrupting the fibres to bond together starts at 100 psi but the more pressure the better as far as I have read.

1. what is the maximum pressure that could be achieved on say a 4" diameter brickette by a long lever a person could hang on ?

2. How do I design levers to exert maximum force ?

 

[EdStainless]

There are a lot of designs for these out there.
People making bricks from biomass (Sargasso for example) use them.
The limit isn't the max force, it is how much the material compresses.
Someone pulling down can exert their body weight as a maximum.
125lb person on a 20:1 leaver will result in 2500lb.
On your 12.6sqin puck you will be just shy of 200psi.
But the lever travel will be 20x the compression travel and that long stroke might not work.
There are a lot of cleaver compound (4 bar linkage) designs that let you ratchet your way down and apply a lot more force and take the compression in stages.
Work on your searching terms.

 

[3DDave]

Here's an example:

 

[dvd]

Not much has changed in the world of levers since you asked a similar question last year.

 

[BEMPE16524]

Here's an example:

simple and functional.

 

[LittleInch]

The creaking and bending of the wooden bits in some of those machines tells me they will break pretty fast.

Don't forget that with lever multiplication of forces comes added moment in the beam and high point loads.

Recently I bought a log splitter based on similar principles and within 10 logs the beam bent.

But in answer to your questions,

1) Almost unlimited, but varies with the weight of the person and how strong your beam is. The answer above gives you some practical data.

2( Aplication of basic lever design / high school mechanics