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02-18-2010, 08:59 AM   #1
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## How do I calculate this angle?

I have a 2x12 that I need to cut a 22.5 degree angle in. It has to start from 3-3/4" in from the top end, but how do I know how far I need to mark it down the side (see pic)? Thanks!

JP
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02-18-2010, 09:16 AM   #2
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I don't have a scientific calculator here, but to figure it out 3.75 multiplied by the tangent of 22.5° will give you the height. I drew it up and it is 1.553" or 1-9/16".

02-18-2010, 10:02 AM   #3
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A 5-12 pitch works out to 22.6195 degrees.

Is that close enough?

I calculate the length as 1 35/64ths.
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02-18-2010, 10:04 AM   #4
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Quote:
 Originally Posted by jlhaslip A 5-12 pitch works out to 22.6195 degrees. Is that close enough? I calculate the length as 1 35/64ths.
Now that's what I'm talkin' about jlhaslip! Kick ass! Although, I don't think my tape measure has 35/64th marks. How do I mark it? Thanks!

JP

 02-18-2010, 12:08 PM #5 Household Handyman   Join Date: Feb 2009 Location: Albany, Ga. Posts: 2,478 Rewards Points: 1,408 s.w.a.g. ?
02-18-2010, 12:09 PM   #6
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Quote:
 Originally Posted by Thurman s.w.a.g. ?
What is that?

02-18-2010, 12:31 PM   #7
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Quote:
 Originally Posted by jpearson311 What is that?
http://www.acronymfinder.com/SWAG.html
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02-18-2010, 12:33 PM   #8
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Quote:
 Originally Posted by palibob http://www.acronymfinder.com/swag.html
lolololololol!

 02-18-2010, 12:37 PM #9 Member   Join Date: Jul 2009 Posts: 122 Rewards Points: 75 1.55330086" from the top. any more places you can figure it out. 6th grade math?? J/K
02-18-2010, 12:38 PM   #10
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Quote:
 Originally Posted by baum 1.55330086" from the top. any more places you can figure it out. 6th grade math?? J/K
Thanks. It's been a while since I've worked with tangents.

 02-18-2010, 12:48 PM #11 Member   Join Date: Nov 2007 Location: Nashua, NH, USA Posts: 7,971 Rewards Points: 1,548 A regular corner is 90 degrees (a right angle). Divide it in half as if you were cutting a pizza or a cake. Divide each half in half* to get 22-1/2 degree slices. If you made a cardboard jig like this, would that help you measure? Swag -- Refers to a light fixture hung from the ceiling where the power cord or cable is strung along the ceiling and then down the wall if needed to reach a receptacle. * Easier to eyeball it equally compared with dividing the 90 degree angle into 4 parts all at once. __________________ The good conscientious technician or serviceperson will carry extra oils and lubricants in case the new pump did not come with oil or the oil was accidentally spilled, so the service call can be completed without an extra visit. Last edited by AllanJ; 02-18-2010 at 12:53 PM.
02-18-2010, 12:49 PM   #12
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Quote:
 Originally Posted by AllanJ A regular corner is 90 degrees. Divide it in half as if you were cutting a pizza or a cake. Divide each half in half to get 22-1/2 degree slivers. If you made a cardboard jig like this, would that help you measure? Swag -- Refers to a light fixture hung from the ceiling where the power cord or cable is strung along the ceiling and then down the wall if needed to reach a receptacle.
Actually I just made a paper jig not cardboard. Thanks! I'm new to this forum, but everyone on here is so quick and helpful.

02-18-2010, 04:46 PM   #13
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S.cientific W.ild A.ss G.uess
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02-18-2010, 05:33 PM   #15
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