Okay, not really a step by step, but a few WIP shots with explanations of how I converted the Jericho.
First a small description of the materials I used :
1) PVC foamboard : http://en.wikipedia.org/wiki/Closed-cell_PVC_foamboard
This forms the bulk of the structure. I bought it in 2mm thick sheets at my DIY shop.
It's really easy to work, cut, carve and will hold its shape pretty well.
2) Sheet styrene, 0.5mm thick
3) green stuff/milliput in a 50/50 combination
First I started with the side skirts:
85mm * 15mm strips on top of 2 small triangles and an additional 65*2 strip
This gave a me a strong base for the pod.
Then I constructed the pod with one large 55* 4 sheet for the top and 2 strips of 60*10 per side.
The front structure was mostly done by trials and errors.
I then added a back bracer for the pod where the magnets for the opening are:
Next step are the characteritic raised skirts of the praetor constructed as boxes, 2 small PVC triangles on each side and a rectangle of 0.5mm styrene on top:
To add detailling and hide junctions I add additional sheets of 0.5mm styrene on tiop of the raised skirts, and 2.5mm strips of 0.5mm styrene :
I also added a bit from the original manticore and rear bracings for the pod.
I started to fill the gaps with the green stuff/milliput mixture.
Final step was to add the missiles and finish the pod :
The missiles are made from reynold paper mates clear end and filled with greenstuff/milliput.
I will probably go back to it to add some rivets once I'm happy with a technique.