Can't Move parts of a sketch

[Rosie_roses]

This seems like a silly question. But I'm stuck trying to move some lines in a sketch. 

I basically made a dimension 500mm when it should have been 50mm, and 150mm when it should have been 15mm. So I decided I wanted to copy or move the end of the model, and then I could make the semi-circle smaller. But I can't move the lines I selected. Or copy them, or copy the whole sketch. And if I just select the semi-circle and edit the dimension, it does not change it in the way I would like. 

Any ideas? Really I just want the parts that are 150 to be 15, and the parts that are 500 to be 50. While maintaining the dimensions of the castling. 

Rosie. 

[DDMFGCOINC]

You should be able to just change the dimensions from 150mm & 500mm to 15mm & 50mm without having to move everything. The other dimensions will stay what they are, though you will have to adjust some of the other unconstrained features.

As far as the move command is concerned, use the arrows to move, not the center square which will change your anchor point.

[Rosie_roses]

I tried changing the dimension and it didn't work out how I would like. Have a look at screencast. 

[Rosie_roses]

Also, Is it possible to just pick up some lines and move them to one side? Without dragging the rest of the object around? I'm thinking of just taking the bit that is the right size away and starting again. 

[chrisplyler]

Dbl-click on a dimension itself. Change its value.

[DDMFGCOINC · Accepted solution]

The sketch will do some odd things because it is so unconstrained.

I've attached a file that I've added some constraints, in an effort to control what moves. It is still not fully constrained, because I do not know your ultimate goal with the part. 

I was however able to adjust the two dimensions that you were looking for.

Let me know if this helps!

[DDMFGCOINC]

When you draw lines they will typically have a coincident constraint  at their intersection (I did find one in your sketch that was not). The coincident constraint would have to be broken, then you could move them.

You should still always constrain your sketches completely.

[Rosie_roses]

Thanks, that is not exactly what I'm looking for, but it gives me a good idea of what to do. 

I think I really need to practice constraining sketches properly and better sketching practices. I feel like I have a bit to learn about proper fusion workflow. If you know of any good tutorials let me know. I often find ones going through the tools, but there seems to be less about more complex shapes, or good practice, Etiquette and workflow.  

Rosie.