how to figure the angle....

[randy41]

i own the bows to a 22' wide high tunnel (greenhouse). i have attached a drawing of the frame layout. what is the angle at the peak?

part 2

how would i accurately bend a 3' length of 1 7/8" 16 ga. galvanized steel tubing in the middle to that angle? i'm not sure that it really is going to be 3' yet.

 

[magicheater]

looks to be about 60 degrees. You have just under a 7/12 pitch roof.

 

[Egon]

If it's drawn on squared paper a ruler and protractor should give a pretty good idea.

 

[tmeadows]

Builders Construction Calculators - Contractors, Tradies and DIY This link came from another post but I do not know how to link the post. hope it helps

 

[Paul N]

Magicheater is right. I just did the math on it. It calculates to 59.489 degrees. A conduit bender might work, but it's gonna be tough to bend something that big by hand. You might ask an electrician if he has a power bender.

 

[Domush]

Most auto shops and metal shops have a hydraulic press which can make the bend in a few moments. The local shop I use can bend a pile of pieces for you in 5 minutes flat, about $15-20 max. Save your muscle and bring it in to a shop with the right equipment.

 

[randy41]

thanks! i looked at my other high tunnel and the bend is not as sharp as the drawing shows. i will need 13 of them and i like the idea of going to the local auto shop to get them bent.

 

[Domush]

As for determining the real angle, get yourself an angle finder from harbor freight for 5 bucks. You set it on any angle and it tells you what it is. Do this on both sides of the peak, average the two angles, then subtract from 180. Boom! Perfect angle every time.

I used this method when I added onto my carport.

Sent from my SCH-I500 using TractorByNet

 

[drssg]

I come up with 120 degrees, using the math geek approach.

Starting from the peak, I go down 5' and over to the left 8.5'. That forms a right triangle. The angle at the top of that triangle is inverse tangent of (8.5 / 5). Plug that into the Microsoft Windows calculator in scientific mode, and it's very close to 60 degrees. So the total angle at the peak of the roof is twice that.

 

[mvwicker]

I come up with 120 degrees, using the math geek approach.

Starting from the peak, I go down 5' and over to the left 8.5'. That forms a right triangle. The angle at the top of that triangle is inverse tangent of (8.5 / 5). Plug that into the Microsoft Windows calculator in scientific mode, and it's very close to 60 degrees. So the total angle at the peak of the roof is twice that.

Yep, I got the same result, only using 7' over and 4' down on the graph. That gives a half-angle of arctan(7/4) = 60.25 degrees at the peak. The excess is negligible (15 moa, about as well as I can shoot , so a 120 degree bend should do fine.