Simple static load problem giving me hell (sketch provided)

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The discussion revolves around a design evaluation problem involving static load analysis at pin joints. The user is attempting to verify the reaction forces calculated by WorkingModel software against hand calculations but finds discrepancies, particularly in the sum of forces in the X direction, which does not equal zero as expected. The load in question is a 10kgF acting downward, and the user has provided coordinates for the pin joints and load application. Despite using fundamental equilibrium equations, the software's output seems incorrect, leading to confusion about the validity of the results. The user seeks clarification on whether the software's calculations or their understanding of the problem is flawed.
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Homework Statement



This is not actually a homework problem but a design evaluation problem I have encountered.
I am trying to solve for all the loads at the pins and have used WorkingModel to try and give me some quick answers. However, the solutions offered by the software do not make sense to me/can't verify with hand calcs.

The image below shows the values of Fx, Fy and F as calculated by the software at each pin. I have added the co-ordinates of where the pin joints are and where the load acts (in mm). +X is to the right, +Y is to up. The load acting on this system is a 10kgF acting directly down as shown. Each grid square is 50mm wide. The mass of the elements is set to zero.

[PLAIN]http://img833.imageshack.us/img833/7528/forces.jpg

The unknowns are the reaction forces (Fx, Fy) at each of fixed pins 11 and 3 and the force acting on the pin at 13.

Homework Equations



Ʃ forces in X direction = 0
Ʃ forces in Y direction = 0
Ʃ moments about any point = 0
M=F.x
cos(θ)=A/H
sin(theta)=O/H
tan(θ)=O/A

The Attempt at a Solution



Unless I have severely overlooked something, I immediately dismiss the solutions offered by the software because a simple check of the equation:

Ʃ forces in X direction = 0
...reveals that this is NOT the case.

Ʃ forces in X direction = Fx@pin11 + Fx@pin3 + Fx@LOAD
= (-5.186) + (16.305) + (0)
≠ 0!

??

What is going on here? Am i going loco or is this solution just plain out wrong?

Thanks
 
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(hand calc removed because of error)
 
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