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  #1  
Old 01-19-2017, 03:18 PM
rasun rasun is offline
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Default Duct miter question

Is it a formula to miter a duct and make your finished product the length you want? For examole, I need a 2 footer of 12 by 8 setting 6 inches. I know if I miter the 2 footer the finished product would be less than 24" because of the cut off. Is it a formula to make the piece 24" after I miter it? Thanks in advance for your help
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  #2  
Old 01-25-2017, 10:45 AM
tinstructor tinstructor is offline
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Default 1-piece offset question

Quote:
Originally Posted by rasun View Post
Is it a formula to miter a duct and make your finished product the length you want? For examole, I need a 2 footer of 12 by 8 setting 6 inches. I know if I miter the 2 footer the finished product would be less than 24" because of the cut off. Is it a formula to make the piece 24" after I miter it? Thanks in advance for your help
>First,before I answer your question, do you have experience with a trig/ math calculator ?
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  #3  
Old 01-25-2017, 12:17 PM
rasun rasun is offline
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Yes, I know about sin/cosine, etc.
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  #4  
Old 01-27-2017, 01:12 PM
tinstructor tinstructor is offline
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Sorry for the late reply. My internet service has been down for a couple of days.
Just threw this sketch together to show what seems to be the shortest most direct way to use math to solve the "field miter" question to get an exact finished length.

In this example I used the exact dimensions required by the author of the question.This time though, because of time constraints, there is no explanation of the "why",only the "how". Remember, if you're using slips and drives,do your calculation one inch short of the finish (drive-to-drive) measurement.
Also,this caveat...Duct width sizes can grow dramatically when doing field miter cuts of this type. A 12 wide duct,24 inches long,just like the one in the drawing example,but with a 10" offset,grows to 13 INCHES !! 😭 (LET'S KEEP OUR STANDARDS HIGH And do quality work !!👌👍👏
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The Following 2 Users Say Thank You to tinstructor For This Useful Post:
Bud (01-27-2017), tinnerjohn (01-27-2017)
  #5  
Old 01-27-2017, 01:54 PM
rasun rasun is offline
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Thanks a lot for your response. I greatly appreciate it
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  #6  
Old 01-27-2017, 05:18 PM
tinstructor tinstructor is offline
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You're very welcome. If you have any additional questions , I welcome them all. There is no such thing as a stupid question !😀
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