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    Distinguished Contributor
    Posts: 399
    Registered: ‎12-01-2003

    Flex duct Problems.

    418 Views, 7 Replies
    07-07-2003 12:10 AM
    I'm trying to add flex duct to connect my diffusers to my low pressure ductwork. If I use hard round ductwork everything works fine and looks good. If I try to perform the exact same inputs using flex, the ductwork shoots way out to no where land and comes in all messed up. Is there any special requirement when adding flex duct from a diffuser to hard rectangular ductwork? Has anyone been able to due this successfully?
    Please use plain text.
    Valued Contributor
    Posts: 90
    Registered: ‎12-10-2003

    Re: Flex duct Problems.

    07-07-2003 09:02 PM in reply to: jmcfaddn
    I have had the same problem many times and the only solution I have found so far is once you have selected the connection point for the start of the flex duct, pick another point to continue placing the flex, and then select the diffuser. For some reason the routine does not function when selecting only 2 points (take-off to diffuser). I hope this helps....Aaron
    Aaron A. Gray
    Advance Design
    369 Sagamore Drive
    Rochester, NY 14617
    585-734-8277
    Please use plain text.
    Distinguished Contributor
    Posts: 399
    Registered: ‎12-01-2003

    Re:

    07-07-2003 10:08 PM in reply to: jmcfaddn
    Yes, that is what I was trying and actually got worse results than connecting directly to the ductwork.
    Please use plain text.
    Valued Contributor
    Posts: 90
    Registered: ‎12-10-2003

    Re:

    07-08-2003 01:06 AM in reply to: jmcfaddn
    Hmmm, so my suggestion did not work for you? I am not sure what you meant by "connecting directly to the duct". Are you connecting from the diffuser to the duct? I am assuming you have a tap in the side of a main duct run and want to connect from the tap to the diffuser. I have also played around with the Flex Duct settings in the Duct Preferences dialog and changed the radius curve to 1 and the segment mode to arc......good luck!....Aaron
    Aaron A. Gray
    Advance Design
    369 Sagamore Drive
    Rochester, NY 14617
    585-734-8277
    Please use plain text.
    *[Autodesk], Kevin Mak

    Re: Flex duct Problems.

    07-09-2003 12:39 AM in reply to: jmcfaddn
    Hi Jody,

     

    Aren't you using spline mode flex duct for
    connection? Connect with arc flex segment will get odd
    results like yours in this case. If you are using spline segment, please
    check the osnap settings and make sure it's "osnapping" to the correct
    duct or connector when connecting from diffuser, especially when you have
    overlapping ductworks. If it still doesn't work for you, would you
    mind sending me the drawing so that I can take a look?

     

    Thanks,

     

    Kevin Mak [Autodesk]


    style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
    I'm
    trying to add flex duct to connect my diffusers to my low pressure ductwork.
    If I use hard round ductwork everything works fine and looks good. If I try to
    perform the exact same inputs using flex, the ductwork shoots way out to no
    where land and comes in all messed up. Is there any special requirement when
    adding flex duct from a diffuser to hard rectangular ductwork? Has anyone been
    able to due this successfully?
    Please use plain text.
    Distinguished Contributor
    Posts: 399
    Registered: ‎12-01-2003

    Re:

    07-09-2003 03:32 AM in reply to: jmcfaddn
    To put it bluntly, the spline routine is a piece of (edited).
    Have you ever taken a tube and twisted it? The throat will deform choking off the clearance inside. That's exactly what that spline routine does. The ductwork does not hold its shape. At certain points on a 10"dia. duct it looks like its almost flat and have 2" of clearance.
    Please use plain text.
    *[Autodesk], Kevin Mak

    Re:

    07-09-2003 05:27 AM in reply to: jmcfaddn
    Jody,

     

    There is a display problem on spline flex duct. We
    know about it.

     

    Kevin Mak [Autodesk]


    style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
    To
    put it bluntly, the spline routine is a piece of (edited).
    Have you ever
    taken a tube and twisted it? The throat will deform choking off the clearance
    inside. That's exactly what that spline routine does. The ductwork does not
    hold its shape. At certain points on a 10"dia. duct it looks like its almost
    flat and have 2" of clearance.
    Please use plain text.
    *[Autodesk], Kevin Mak

    Re:

    07-09-2003 05:34 AM in reply to: jmcfaddn
    It seems to happen when the connection
    is very close to the end of the duct. There is a simple work-around
    for this problem: Turn ORTHO on, select the endcap and the rectangular
    duct, grab the endpoint and extend the duct (lengthens it!!). Then I will be
    able to make the flex duct connection without any problem. After the connections
    are done, bring the endpoint of the duct and the endcap back to the original
    location. Hope this helps.

     

    Kevin Mak [Autodesk]


    style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">

    Hi Jody,

     

    Aren't you using spline mode flex duct for
    connection? Connect with arc flex segment will get odd
    results like yours in this case. If you are using spline segment, please
    check the osnap settings and make sure it's "osnapping" to the correct
    duct or connector when connecting from diffuser, especially when you have
    overlapping ductworks. If it still doesn't work for you, would you
    mind sending me the drawing so that I can take a look?

     

    Thanks,

     

    Kevin Mak [Autodesk]


    style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
    I'm
    trying to add flex duct to connect my diffusers to my low pressure ductwork.
    If I use hard round ductwork everything works fine and looks good. If I try
    to perform the exact same inputs using flex, the ductwork shoots way out to
    no where land and comes in all messed up. Is there any special requirement
    when adding flex duct from a diffuser to hard rectangular ductwork? Has
    anyone been able to due this
    successfully?
    Please use plain text.