Making Prototypes - Album Sleeve

After my crit meeting with my lecturers I have decided that it would be easier and more aesthetically pleasing to come up with an album sleeve rather a CD cover that would go into a Jewel case. Because of my decision I went ahead and did a few sketches to figure out the dimensions.

This was going to be my first prototype; my dimensions were 12.7cm x 13cm x 13cm (the width for the three parts) and the height would be 13cm, with an additional 1cm for each flap on the insert section.

The paper I had used is from my sketchpad, as I want to use paper of a similar thickness for my final design. I have also taken into account that the thickness of the paper would mean that the dimensions might seem slightly smaller than usual.

My initial sketch with dimensions after measuring a CD

The first prototype! 

Once the prototype was made I glued the tabs down and slid the CD into the insert, just so I could make some annotations. I realised that the dimensions were slightly too big as the CD kept slipping out really easily, as the gap was too large. However the gap that was created between the insert and the front was perfect, as the front could easily be folded over without creasing the insert edge.

I then drew up another sketch with smaller dimensions, and made my second prototype.

Slipping the CD into the insert I realised that it just fit into it; if I had been a millimeter in the CD wouldn't have been able to fit. I realised that I would need to make it slightly bigger.
The gap between the insert and front was much too small, as when I folded it over it creased the edges slightly.

Taking this all into account I realised that I needed the dimensions of the insert to just be slightly bigger than my second prototype, but with the same difference in the gap between the insert and front like my first prototype. I realised that because of this the sleeve wouldn't necessarily be square like I thought it would be.

My next prototype from this is (3)

And now not only the CD slotted perfectly into the insert, but the gap between that and the front was perfect as it was enough for the front to fold without creasing it. This means that I am able to do up my design in Indesign!

Conclusion:
By creating a prototype before going onto InDesign does save me a lot of trouble; if I had gone with my original dimensions I would've realised all too late that it was too big for the CD.