need tight 90 off side of plenum

Reply

  #1  
Old 10-29-11, 06:59 AM
C
Member
Thread Starter
Join Date: Apr 2002
Location: USA
Posts: 220
Received 0 Votes on 0 Posts
need tight 90 off side of plenum

im adding a zone for my basement. to do this I am comming off of the side of the plenum. I purchased a broadway 90 and starter collar thinking this would work but its adding 6 inches. I need to make a 90 off the side of the plenum how would I go about doing this?

Thanks
 
Sponsored Links
  #2  
Old 10-29-11, 07:10 AM
airman.1994's Avatar
Member
Join Date: Dec 2005
Location: VA
Posts: 5,795
Received 8 Votes on 8 Posts
Dove tail the 90 and forget the starting collar. Might be hard to get a damper in it but can be done.
 
  #3  
Old 10-29-11, 07:34 AM
C
Member
Thread Starter
Join Date: Apr 2002
Location: USA
Posts: 220
Received 0 Votes on 0 Posts
Originally Posted by airman.1994 View Post
Dove tail the 90 and forget the starting collar. Might be hard to get a damper in it but can be done.
not worried about damper as there will be a zone damper a tad down stream where I have room

do you have a picture of how to dove tail the 90?

Thanks
 
  #4  
Old 10-29-11, 11:58 AM
airman.1994's Avatar
Member
Join Date: Dec 2005
Location: VA
Posts: 5,795
Received 8 Votes on 8 Posts
Zone damper on a branch line? This sounds like a unit killer.
 
  #5  
Old 10-29-11, 12:02 PM
airman.1994's Avatar
Member
Join Date: Dec 2005
Location: VA
Posts: 5,795
Received 8 Votes on 8 Posts
Duct Take-Off Collars. Here is a pic
 
  #6  
Old 10-29-11, 01:14 PM
F
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,495
Received 35 Votes on 27 Posts
do you have a picture of how to dove tail the 90?
Dovetail means to come off the main at an angle rather than at 90 degrees. It requires an elliptical hole in the plenum and the "starting piece" will have to be field cut and tabbed to fit. Not a difficult job for a skilled sheet-metal worker but definitely not easy for a beginner.
 
  #7  
Old 10-29-11, 02:46 PM
C
Member
Thread Starter
Join Date: Apr 2002
Location: USA
Posts: 220
Received 0 Votes on 0 Posts
Originally Posted by airman.1994 View Post
Zone damper on a branch line? This sounds like a unit killer.
zoning system with bypass
 
  #8  
Old 10-29-11, 02:50 PM
C
Member
Thread Starter
Join Date: Apr 2002
Location: USA
Posts: 220
Received 0 Votes on 0 Posts
Originally Posted by Furd View Post
Dovetail means to come off the main at an angle rather than at 90 degrees. It requires an elliptical hole in the plenum and the "starting piece" will have to be field cut and tabbed to fit. Not a difficult job for a skilled sheet-metal worker but definitely not easy for a beginner.
i was talking to someone in the hvac field and they told me to cut the hole and inch shorter than my additional trunk line. then the remaing inch will be used as a flap and just slide the broadway fitting in. does this sound right?
 
  #9  
Old 10-29-11, 03:52 PM
F
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,495
Received 35 Votes on 27 Posts
I don't know what a "broadway" fitting is. I CAN do the dovetail but I can't explain HOW to do it.
 
  #10  
Old 10-29-11, 04:42 PM
C
Member
Thread Starter
Join Date: Apr 2002
Location: USA
Posts: 220
Received 0 Votes on 0 Posts
Originally Posted by Furd View Post
I don't know what a "broadway" fitting is. I CAN do the dovetail but I can't explain HOW to do it.
second fitting on the below page is what I have.

http://www.graymetalsouth.com/cat043pg.html#122sd
 
  #11  
Old 10-29-11, 11:27 PM
F
Member
Join Date: Mar 2006
Location: Wet side of Washington state.
Posts: 18,495
Received 35 Votes on 27 Posts
I can't explain how to do it. I suggest that you go to the public library and find some older books on sheet-metal work. Audel's Guides are good. They will explain in detail and with pictures how to cut the hole, flange it and install the S clips and drive cleats. It isn't rocket science but it does take some know-how AND some specialized hand tools.
 
Reply
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: