Understanding Force Diagrams for Hydraulic Cylinder Selection

[cjpa]

Hello world,

I have to select an hydraulic cylinder to counter-balance a force. For that purpose I need to know the force that my hydraulic cylinder must exert. Typically I would use the horizontal part of F2, but being that force with diferent degrees, doen't my friction play an important role? usually I don't consider it... can anyone, please, help
me solve this. I am having a bit of a trouble understanding this mechanism's force diagram...

 

[mfb]

You will need some minimal coefficient of friction to prevent the block from sliding, but if you have that the type of connection does not matter.

 

[cjpa]

Thanks for you kind reply mfb.

Well, I've been struggling with this all night and I have finally been able to do the math, the thing is it does matter, the degree of the connection. And it is loggical if you think on the "limit" of the angles for each. yet, the friction plays a minor role, and therefore can be ignored.

i'll attach an excel with some simple math solving this.
(please, if you find any error let me know)