Is that an assembly of parts? or one big happy complex part (like a STP or IGES file?)
Is there a constraint preventing it form moving left (like a mate / face to face constraint between the flange the end of the rectangular block?)
If you modify the rectangular part, does it grow as intended (lengthen as you want? but in the other direction (right end?)
Assemblies a re easier to manage & manipulate. and changes are easier too!! and your model tree is simple! You can also then take advantage of the array / pattern command for your gussets. and you can make one assembly, copy it to another file, then 'replace' a part or two, and you'll have both assemblies.. Also, you can then detail the pieces easier..
Now go render it with a nice shiny 'gloss charcoal grey'
(for what it's worth, I'm a 'Creo' (Pro Engineer) guy, with many many years is 3D cad!)
I am dreading drawing the pulley system that raises and lowers the boom arm !
But that is for later. gotta finish the boom arm and the vertical post along with the pivot section between the arm and vertical section
I love a challenge with cad .
Once you can convey the procedure as to what you want done to the model and where the program can understand you it is a breeze
CAD Learning curve & rocketry flight plot are about the same! Steep at the beginning, but level off after a while!
It'll be easier than you think. The pulleys are an off the shelf item (at least I assume so), so I wouldn't worry about modelling them. Ensure your pivot point is clear, and use an angle constraint to move the gantry thru it's motion.. Check for collisions!
It's one thing to model the parts & build the assembly. it's another entirely to make detailed drawings!
I have the boom part of the boom launcher almost done . I gotta start with inserting bolts in the holes I made
Then will come the "pivot" section and last will be the vertical fixed section . The pulley section will be added once the boom and vertical fixed section are are joined
It looks like you are missing your pulley wheel on the lower assembly. But that can be added later.
The next step is to start making your production drawings. Are you making this out of .. metal? And having it machined & welded up? Can you drop some numbers? So I / we can get an ide of how big / thick / long this thing is..
In Creo, you can add one bolt assembly to your 1st hole itn eh patter, then it'll fill all the patterned holes with the bolt assembly. Dunno if SW allows for that. Otherwise, array / pattern your bolt assembly..