Hi everyone, welcome to today’s continuation of the multi-part tutorial on modeling of a tank. This is the 7th part of a multi-part tutorial on creating a military tank. Today, we look at using circles, ellipses, editable splines, boolean tool, and refine tool, to create the editable splines to be used by the loft object to create the barrel loft for our tank.

1. click create tab

2. click Shapes button

3. select object type of Splines

4. click Circle button

5. click and drag a circle in top view, and change its name to barrelinner01, radius to 5.5

6. Shift + click and drag barrelinner01 to the right, to create a copy of the circle called barrelinner02, then click OK

7. Shift + click and drag barrelinner02 to the right, to create a copy of the circle called barrelinner03, then click OK

8. click barrelinner01, then Shift + click and drag barrelinner01 to the right, to create a copy of the circle, then click OK

9. select modify tab, and change name to barrel, and radius to 7.5

10. click barrel, then Shift + click and drag barrel to the right, to create a copy of the circle, then click OK

11. select modify tab, and change name to barrelevacuator, and radius to 9

12. click barrelevacuator, then Shift + click and drag barrelevacuator to the right, to create a copy of the circle, then click OK

13. select modify tab, and change name to barrelaim, and radius to 8

14. select barrel, and click align button, then click barrelinner01 (ensure X position, Y position, and Z position checkboxes are all checked), then click OK

15. select barrelevacuator, and click align button, then click barrelinner02 (ensure X position, Y position, and Z position checkboxes are all checked), then click OK

16. select barrelaim, and click align button, then click barrelinner03 (ensure X position, Y position, and Z position checkboxes are all checked), then click OK

17. click ellipse button, and click drag an ellipse, which is partially over the outer circle of barrelaim

18. select ellipse object, and click align button, then click barrelaim (ensure X position, and Z position checkboxes are checked, but Y position checkbox is UNCHECKED), then click OK

19. select all the circles and ellipse, then right-click and select Convert To > Convert to Editable Spline

20. select barrel, right-click barrel, and select Attach, and click barrelinner01, and right-click again, to ‘close’ Attach tool

21. select barrelevacuator, right-click barrelevacuator, and select Attach, and click barrelinner02, and right-click again, to ‘close’ Attach tool

22. select barrelaim, right-click barrelaim, and select Attach, and click barrelinner03, and then click the ellipse object, and right-click again, to ‘close’ Attach tool

23. click barrelaim editable spline

24. click + sign beside Editable Spline in the modifier stack,

25. select Spline, to enter spline editing mode

26. select the outer spline, ensure merge option of Boolean is selected, then click Boolean, and click the ellipse, to merge the outer spline and ellipse into one spline

27. select vertex, to enter vertex editing mode

28. select top vertice of the merged outer spline, right-click, then select Make First (the first vertex of that spline will turn yellow, to indicate that it is now the first vertex of that spline)

29. select barrelaim editable spline

30. click + sign beside Editable Spline in the modifier stack

31. select Vertex, to enter vertex editing mode

32. select top vertice of the outer spline, right-click, then select Make First (the first vertex of that spline will turn yellow, to indicate that it is now the first vertex of that spline)

note: we are setting the top vertex of each outer spline as the top vertex, so first vertex for each of the outer spline will all be in the same relative position, to ensure lofting operation which will use these splines will work correctly

33. right-click a vertex, and select Refine, then click 2 times on left of top vertex, to add 2 vertices on left of top vertex, and click 2 times on right of top vertex, to add 2 vertices on right of the top vertex

note: we are adding 2 vertices on left of top vertex, and 2 vertices on right of the top vertex, to ensure number of vertices for all outer splines are the same, and are in the same relative positions, to ensure lofting operation which will use these splines will work correctly

34. select barrel editable spline

35. repeat steps#30 to 33, for barrel editable spline