Quarta consegna

I created an extrusion, going on extrusion and setting two reference planes. I assigned the dimensions, which parameterize: Length : 4000 cm Width : 200 cm I gave 250 cm of thickness to this object. 

I created the buttonholes for the screws. 

Then, I did, extrusion > circle. From properties > solid > void I could create an object that can pierce the previous one.

With the cut command, I select the two objects and create a void.

Now I create the "mother" part that will support the "child" object, starting from metric generic model.

I created the shape of my object mixing diverse elements. The child object will be stick to this part after it.