Greelt, might I make a few suggestions for your thrust structure? You might want too consider adding some tips on the correct method too print out the parts correctly. With Tons Saturn V there seems too have been some confusion on this matter. Such as print at 200% too get 1:48, but if you print at 100% you still get 1:48, fit too page, dont fit too page, etc, etc. I know you have a scale on your sheets, but this would help out a novice like me. Another thing I found handy with Ton' s Saturn V was a pattern for the rings which are required in the rocket tube itself. Just speaking for myself, I would have a hard time getting the rings the right measurement too begin with, let alone make a perfect circle. With Ton's, I used the single pattern too cut out the cardboard for all of the rings in the first and second stage. Have a great day.