refit and start jpeg

I've never understood the scale that is used when I hit the full view icon. I suppose there are a lot of things considered when the program scales the window; things like datums, points, coordinate systems, etc. Likely for your situation I would guess it's trying to size based upon the flat pattern? I find this to be a particularly annoying problem when I'm using imported data to build models and that data includes a lot of stuff I don't need and I don't want to spend hours using the Data Doctor to remove it.

What you can do is orient your model the way you want, zoom it as much as you can to fit the screen, then save a view via:

View -> Orient -> New

And naming it something meaningful. Then when you want to make your jpeg you jump to that saved view via the Saved Orientations button on the ribbon. Your saved view will be listed there.