Drawing Cylindrical and rectangular ducting help

[Allison]

Hi everyone,

I have two questions I am stuck on:

(1)

I have drawn an extruded rectangle to create a floor-standing boiler. From the top of that, there is cylindrical ducting that rises to a height of 1250mm. This cylindrical ducting initially rises vertically and then continues up at a sloping angle right towards the external wall. I have drawn a circle to represent the ducting coming out of the top of the boiler, and have extruded this circle (by 416mm) to represent its vertical height before it starts sloping. I have also done a circular wall subtraction at a greater height position (and to the same dimensions) on the external wall, where the ducting will meet the outside. So in effect I currently have a vertical cylinder sitting on top of my boiler (416mm tall). How do I now get this to continue upwards and sloping to meet the hole in the wall I created? The boiler is positioned slightly away from the external wall.

(2)

I think the answer for the first may help with my second question. Across the length of my building (one storey) I have a ducted warm air system comprising a 450 x 240mm galvanized ducting containing four 300 x 300mm outlet grilles delivering warm air vertically down from the duct. I initially drew this as a dashed-line rectangle, doing a duplicate array to create four evenly spaced 300 x 300mm squares to represent the outlet grilles. I then extruded the whole thing and moved it up the vertical height required. However, I have realised that towards the front of the building, the ducting is at a higher height than at the back of the building, where the ceiling height is lower. So I am thinking that in effect I need to draw two separate extruded rectangles raised to different heights, to accommodate the differences in ceiling heights, along which the ducting runs. But if I do this, how do I join the two sections of ducting together to create one that basically slopes down between the two ceiling heights? The section that has to join both ducting ends has to be sloped to meet both different heights, and I don't know how to do this.

I hope I have explained well enough for someone to understand what I am trying to achieve, and I look forward to a helpful answer soon.

Thanks in advance

[islandmon]

Try > ExtrudeAlongPath

[Allison]

I still can't fathom this. I have never used extrude along path before so I went into help, but its too confusing because I don't know all the terms. I've also messed around with the cylinder tool but its not creating what I need.

I think the best way for me to describe what I'm trying to do is to imagine one of those fire stoves that sit on a heart with a closing door over the fire (they're usually cast iron), or an Aga cooker. They have a cylindrical pipe coming out of the top of them that rises up vertically, then slopes backwards towards the wall, whilst still rising vertically, then finishing up flush to the wall (where they will extract outdoors). So the bottom of this type of flue will start on top of the cooker or fire horizontally, then finish on the wall vertically.

Can anyone explain an easy way to do this - there must be one?

[Pat Stanford]

Here are the directions if the pipes will all run in one plane. If they need to move in two planes, you will need to change the polyline to a NURBS curve and edit it. Or, break it into multiple pieces that each is in one plane.

1. Look at your scene in an elevation view looking directly at the plane the pipes need to run in.

2. Draw a polyline (so you can use curves and not just straight line segments [or draw a polygon and then use the 2D Reshape tool to edit the vertices that should be curves]) where the center of the pipes should be, starting at the stove and ending at the wall.

3. Draw a circle the correct diameter for the pipes.

4. Select the circle and the polyline.

5. Extrude Along Path with the polyline highlighted.

HTH,

Pat

[mike m oz]

THree ways of doing this:

- Extrude along path (as Islandmon suggests) see here: http://architoshforums.forest.net/showthread.php?t=1307

- Use the HVAC objects from the Building Sevice tool set.

- Use the 3D primitives (you will need to add these to your Workspace).

Note: The 3D primitives are very useful and have a range of options. For example there are frustrum options for the cone and pyramid.