Help / Guidance with building a routine for air conditioning duct layout

[stephen.coff]

Guys,
In my line of work (HVAC Draftsman) I draw rectangular boxes of set sizes and lengths. These boxes will be all joined together in a continuous run starting in one place and ending in another. They often bends and turns as it snakes along on it's path and decreases in size as it progresses, It is air conditioning duct.
I would like to be able to make a routine that asks the width and length of the rectangles and then asks for me to draw the path/ route with a polyline. Once done then converts the polyline into the rectangular blocks at the specified width and length. when it changes direction places a radius etc.
I am not sure where to start or how to go about getting the data of the polyline (length of straight and angles/ direction) and then convert it to the rectangles.
I am expecting this to be some what a challenge, I'm asking if anyone has a routine that may do something totally different though could work as a good base point to start from.

If anyone could give any advice to point me in the correct direction as how I should approach this ? Anything would be greatly appreciated.


Regards

Stephen

[Opie]

Do you have a drawing or image that shows the steps or the final product (preferably the steps)?

[Lions60]

I found this website that has possibly what your are looking for. it is called HVACSimiliar http://www.cadopolis.com/shareware/s...0&TheKeywords=

[stephen.coff]

Opie,
Attached is hopefully enough information to explain what I am aiaming to do.
I haven't looked at that site yet though about to.

Thanks guys.

Stepehen

[stephen.coff]

Guys,
Downloaded the HVAC software though no luck. Won't work with 2007, wouldn't even install. Any further Ideas, have you been able to look at the file I left Opie ?

Stephen

[Avatart]

Stephen,

I have a routine that does not quite do what you are after, but it does draw 2D ductwork, square, round and some flat oval. It is detailed as you would expect a Consultant level drawing to be (ie, not very), but it could be a useful tool for you. It is a series of Image menus and Lisp routines and takes a bit of installing (I only really made it for myself). If you can PM me your email address, I can send it over to you with installation instructions.

[Opie]

Guys,
Downloaded the HVAC software though no luck. Won't work with 2007, wouldn't even install. Any further Ideas, have you been able to look at the file I left Opie ?

Stephen

I have. I'm still trying to find some time for it.

Do you have the blocks created you want to use?

Are there any standard widths or will they need to be custom sizes?

Also, will this need to be 3D?

[Avatart]

Of course, ABS does this all already....

[stephen.coff]

Carl,
I will PM you in a moment.
You say ABS does this already ? Does this mean there could be a routine in ABS that could be pulled and utilised for any Autocad user to use ? The second question is how is it done ? Does it just add block after block etc once the parameters are set ie. the block width and length ?
I am actually not sure about the best way to do it, I was looking atanother programe though it seems as though it uses sld files, could this be the case ?
I don't understand the use for sld files to mu understanding it is just an image of the current view when made. Can we insert a sld file like and block ? is this the path I should be looking further at ?

Opie,
Blocks ? As you can probably tell from the above, I really am not sure of the smartest approach to accomplishing this, if it is blocks i could make blocks though thats a lot of blocks as the combination of duct sizes is huge. I think it needs to be something that is custom made on request.

I don't wish to do it by offsetting the polyline and then adding the internal lines to make the spaces as this could get very messy should something be required to change whic is often the case.

Stephen

[Avatart]

Carl,
I will PM you in a moment.
You say ABS does this already ? Does this mean there could be a routine in ABS that could be pulled and utilised for any Autocad user to use ? The second question is how is it done ? Does it just add block after block etc once the parameters are set ie. the block width and length ?
I am actually not sure about the best way to do it, I was looking atanother programe though it seems as though it uses sld files, could this be the case ?
I don't understand the use for sld files to mu understanding it is just an image of the current view when made. Can we insert a sld file like and block ? is this the path I should be looking further at ?

Opie,
Blocks ? As you can probably tell from the above, I really am not sure of the smartest approach to accomplishing this, if it is blocks i could make blocks though thats a lot of blocks as the combination of duct sizes is huge. I think it needs to be something that is custom made on request.

I don't wish to do it by offsetting the polyline and then adding the internal lines to make the spaces as this could get very messy should something be required to change whic is often the case.

Stephen

Stephen,

ABS is a vertical product that sits on top of ADT, which sits on top of AutoCad, you can't strip lumps out to use in raw AutoCad, it just doesn't work that way. They way ABS works is that it has "intelligent objects", which can be used to represent ducts in 2D or 3D and they can contain all the information required to size them (automatically if you want). This is the way in which many people drawing ductwork for a living are working now (myself included).

SLD files are purely images that programmers often use (well, used to use) to drive Image menus, you'll see them in action when I send my ductwork routine over to you. You can't insert them into a drawing, usually they would be accompanied by a block that looks the same and would be inserted by clicking the SLD image in an Image menu.

The way to use Blocks intelligently in AutoCad is done in two ways. If you are using V2006 or above, you can use Dynamic Blocks, which are like the old static blocks, but you can add sizing parameters, so for example, if you have a duct that is 600mm wide x 3000mm long, you would add these as parameters to your Dynamic Block. I have not yet seen a program that adds this data as it inserts them though (not to say that it doesn't exist, I just haven't seen one). The other way is to create a normal static block of your ductwork and use scaling factors when inserting (this is how my program works), so you would have a block of a piece of duct 1mm wide x 1mm long and scale it up at insertion by 600W x 3000L.

There are many other ways that a program can create ductwork, a common one is to take your parameters, supplied by the program and make a bespoke block on the fly, though these can be tricky to edit. Another would be to create just the linework on the fly.

Hope this helps, I'll go check my PM's now.

Carl