How to Create an Equal Tee Between Two Cylinders

File Prefix: TEE

Description: 90 degree equal cylindrical tee piece.

Dimensions:
200mm diameter cylinders. Main cylinder 600mm long. Tee-off 250 mm long from tee point. Tee point at mid point of 600mm cylinder, i.e. 300 mm from each end.

Overview
The following defines the procedure to create a simple 90 degree cylindrical tee between two cylinder of the same size?
The example files are named TEE1.GRD,TEE2.GRD etc. showing the design at various stages as it develops. Use these files togther with the following procedure to understand the design procedure. You can download them here  - TEE.ZIP. Unzip the files into your Sheet Lightning drectory (usually c:/sheet):

Procedure

1. Switch into a 2D view using the V2D command in the left hand designer menu. You should now be in plan view looking at the tiled floor of the room. This procedure is defined to work with the default room size of 1000 long x 1400 wide x 500 high but for other sizes or units you may need to resize the room before commencing design (see the basics for setting the room size). We are now going to create the first cylinder, 600 mm long x 200 mm diameter aligned with Y axis (horizontally on screen).
2. Move the cross cursor to in the design environment (see basics if you have an arrow cursor) to central position towards the top left of the room floor area - an exact position is not important.
3. Press the left hand mouse button. The cursor should now be rubber banding a new object centre line.
4. Move across to the left hand menu and select the the AXES command (you may need to use the 'next'/'previous' paging commands to fnd it). The AXES command should both highlight. This means the next selection in the design area with cause the active center line to snap to the nearest aligned axis (X, Y or Z).
5. Move the cursor back into the design area (it shoud be the cross cursor - otherwise use the left hand mouse button to switch back modes - see the basics).
6. Move the cursor so that the rubber banded center line is aligned closest to the horizontal Y-axis.
7. Select with the right mouse button. The cross cursor movement should snap to the Y-axis. Movement is now restricted to this axis only.
8. At this point you can fix the length of the first object. The bottom of the screen shows the current length of the object center line. While the center line is active either press the F5 key or type a numeric key. An edit box will pop-up requesting the length of the object. Type in 600 to fix a length of 600mm.
9. Type in a length. Make sure the length you type is not too long for the current room size (see the basics for adjusting the room size). Having typed in the length the cursor is fixed at the point where the center line is the typed length on the Y-axis. You can retype the length by pressing numeric keys or pressing F5 again.
10. Having fixed the length  press the right hand mouse button to select the point. The first cylinder object is created from the center line and the cursor is liberated (see TEE1.GRD). The object has a default diameter size (usually 150 mm).
11. The following steps set the cylinder's diameter to 200mm.
12. Select the SECTION command in the left hand menu (use the 'next'/'previous' comand to page through the menu pages). The sections menu will open  in the left hand designer menu and up/down movement of the cursor allows highlights the section commands.
13. Select on the CIRC command to define a circular cross section. The CIRC command and the SNAP command will both highlight. This means the next selection in the design area will snap the cursor to an object for setting a circular section and resizing it.
14. Move the cursor back into the design area (cross cursor) and move close to the cylinder object.
15. Select with the right-hand mouse button. The cursor should snap to the center line of the cylinder. Its movement is now restricted to along the center line.
16. Slide the cursor to a position anywhere along the the center line other than at an end.
17. Select with the right hand button. The cylinder's diameter now becomes active such that the up/down movement of the mouse grows the cylinder's diameter.
18. Press F5 or press a numerical key. An edit box will pop-up to allow you to type in the diameter dimension. Type in 200, the new diameter. Make sure it is not too large for the room size (see the basics for setting the room size). The cylinder diameter is set (see TEE2.GRD).
19. The following steps create the second object, aligned with the X-axis, vertical to the screen and teed onto the first object.
20. Go to the left hand menu and select SNAP. The SNAP command should highlight. This means the next selection in the design area will snap the cursor to the nearest object.
21. Move the cursor back into the design area. Move close to the cylinder and select. The cursor should snap to the cylinder and become restricted to sliding along the cylinder center line.
22. You now need to fix the point at which the second cylnder object (not yet created) will tee-off from the first cylinder. Do the following.
23. Notice the 'Length' parameter on the second line of the screen. This displays the distance of the cursor from one end of the center line along which the cursor is sliding. If you want to fix the point from the other end of the object slide the cursor hard up to the other end. This zero's the 'Length' dimension at that end such that the distance to the cursor is measured from that end.
24. Now press F5 or a numeric key. An edit box will pop-up for you to type in the 'Length' dimension. Type in 300 to fix the cursor at a point 300 mm from the current zero end. This must be less than the total length of the object or an error will occur. The cursor is now fixed at that distance from the zero end.
25. Select with the mouse. A new object center line becomes actve (rubber banding) teeing onto the first object at the selected point.
26. Select the AXES command again. The AXES command should highlight as before.
27. Move back into the design area and move the cursor such that the active center line is aligned nearest to the vertical Y-axis.
28. Select with the mouse. The cursor should snap to the vertical Y-axis.
29. Now press F5 or numeric keys again to type in a length for the second object. Type in 250 to fix the length of the new ceter line along the Y-axis. This fixes the position of the cursor.
30. Select again with the mouse to create the new object, teed on to the first object (see TEE3.GRD).
31. Dialogue boxes will pop-up asking for selections on matching the two object. Select 'No' to matching as it is not important in this case because the same diameter is copied to the new object.
32. This completes the design as seen in the design stage in file  TEE3.GRD in the download TEE.ZIP. Unzip the files into the Sheet Lghtning directory (usually c:/sheet).
33. To see the cut results select the cutting and unfolding commands in the 'Compute' menu (see: obtaining design result).