# Creating Square-to-Round ductwork

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Alright, I'm trying to make a section of ductwork that is a transition from 12x8 square to 8 dia round. I've tried all kinds of methods, but nothing has really gotten me an accurate, realistic model. Any insights?

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oh, and just for clarification (so I don't get laughed at ), I'm trying to do this in 3d.

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http://www.hvacware.net/pvfeature.html

Try with demo.

BTW it is ton of them, some very affordable

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oh, and just for clarification (so I don't get laughed at ), I'm trying to do this in 3d.

here is a quick one I did with rule surf. it is 12x8 to 8 round.

I am sure one of the guys has a lisp proggy that will do it faster though.

12x8to8round.dxf

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surely using 2007 you can use the loft command to do this?

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surely using 2007 you can use the loft command to do this?

2007 does not play well with my video card in my machine here at home. Will give it a go at work though. I have tried the loft command only a couple of times and don't recall it being able to transition from rectangle to circle.

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the loft command can be used for modelling the transition between many different shapes , you can start with a circle and end up with a 6 pointed star going through rectangular and triangular if you wanted, you have to use closed plines i believe, i dont think it wil work through regions

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The difficult portion of a square-to-round is the creation of the four cones that connect the square points to the round. Most often these cones are eccentric cones. At the following link, http://discussion.autodesk.com/thread.jspa?messageID=5466872, I display the methods I have used to create eccentric cones. It also shows some of the Transition shapes you can create once you master the eccentric cone.

IMPORTANT: At the end of that discussion I provide the code necessary to create Solid Transitions of the common duct shapes. (look for the latest posted code). The code has now been tested on r14 thru A2K7.

Regards,

Ronso

A2k7

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You can use the loft command for this. I drew 2 squares of 12x8 and 2 circles of 8 and then lined them on a path. (I use 2 so that you get straight ends)

Next I made an offset of all of these forms of 0.2 and then I lofted the first series and after that the second series. So I had 2 of the ductworks, one of which a little bit smaller then the other....

This shapes I subtracted and what I got was the following picture...

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Great command LOFT, they pinched it from it's brother Inventor.

Nick

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Thank you all very much for all of your advice. I don't really have much experience using the loft command, so I'll be sure to give it a go and then say how it worked out.

One other side question: I'm going to apply a material to these ducts. I was wondering if there is a way to attach something that looks like duct seams and creases in the metal by using an image map and a bump map or something. Does anyone know where I could find some images to use? Or how would I go about making them, as I have next to no experience with bump mapping. Thanks again!

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Yep, works like a charm. Excellent. Thanks everyone! Anyone know how to make 24x24 ceiling diffusers as well?

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as for bump mapping you can create seam looking lines on a square material map and use that applied to you model, with the correct mapping and placement of the lines you can make it look as tho it is seamed without actually needing a bump map as such, when i was creating skins for mapping space ship models for game modifications i always the Paint shop pro and using the bevel tools you can make a line have the appearance of a raised or lowered section which if done to a straight line would give the apparence of a joint line or seam

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Yep, works like a charm. Excellent. Thanks everyone! Anyone know how to make 24x24 ceiling diffusers as well?

you're just gonna have to dive right in man... pick up a book on 3D or something. that's the best way...

or maybe look for a program called Autodesk Building Systems - it's a total 3D package for designing things like HVAC, Plumbing, and Piping - does everything for you, all you do is tell it what you want.

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this was asked again this week - bookmarked for FAQ

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this was asked again this week - bookmarked for FAQ

How did you get this assignment Strix?

Looks like you are doing a great job and working hard.

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I think it was coz I spend WAY too much time loitering about the forum SLW

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hello everyone. i am really new to all this especially the 3d parts and i am needed to draw some square to rounds that are tilted and kind of crazy really. just need to se if there is a site or something that can point me in the direction of step by step on this. Any help would be greatly appreciated!

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Loft.

If you want to unfold it - you should be using Autodesk Inventor.

Students can get Inventor free here http://www.autodesk.com/edcommunity