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Dirt Digger2
03-28-2010, 03:53 PM
i couldn't find the hardscaping section...i thought one was in here or i didn't look hard enough

anyway...i am going to be pouring a pond for a fountain. The pond has a 2.5' radius and i will be pouring the concrete 3" thick so the inside of the pond will be 2.25'. I want a 3" overhang with a cut flagstone, so that will take the inside of the flagstone to 2' radius, the flagstone will be 12"x12" so the outside radius of the flagstone will be 3'.

my question is, with a circumference on the outside of 28' (meaning i need 28 stones) at what angle should i be cutting off both sides of the stone to get a wedge shape that is uniform around....

heres a few pictures to help visualize

thank guys

http://i942.photobucket.com/albums/ad261/dirtdigger222/Beach%20Work/3-21-10018.jpg
http://i942.photobucket.com/albums/ad261/dirtdigger222/Beach%20Work/3-21-10021.jpg
http://i942.photobucket.com/albums/ad261/dirtdigger222/Beach%20Work/3-21-10024.jpg

cet
03-28-2010, 06:50 PM
The circle is 360 degrees. You have 28 pieces so that is 56 cuts. 360 divided by 56=6.4285714.

That's my guess.

gomowdig
03-28-2010, 08:32 PM
First of all DirtDigger2, you might find someone with a degree in CE from Penn State....
But since I always got a real kick out of your farming and dirt moving, I'll give it a shot.

The outer circle of the pavers will have a diameter of 28/3.14 = 8.917 '; the inner circle of the pavers will be approximately 6.917 ' and have a circumference of 3.14 x 6.917 =21.719 '. Dividing by 28 pavers, you have to cut back to 0.776 ' for each paver. You will take off 1.000 - 0.776 =0.3243 ' Now divide by 2 for each side and you have the tangent of the angle = 0.1622 or 9 deg 13 min. I would just mark 0.1622 x 12 or about 1.95 in , make your cut line and saw away. Check my numbers; good luck.

Dirt Digger2
03-28-2010, 08:54 PM
First of all DirtDigger2, you might find someone with a degree in CE from Penn State....
But since I always got a real kick out of your farming and dirt moving, I'll give it a shot.

The outer circle of the pavers will have a diameter of 28/3.14 = 8.917 '; the inner circle of the pavers will be approximately 6.917 ' and have a circumference of 3.14 x 6.917 =21.719 '. Dividing by 28 pavers, you have to cut back to 0.776 ' for each paver. You will take off 1.000 - 0.776 =0.3243 ' Now divide by 2 for each side and you have the tangent of the angle = 0.1622 or 9 deg 13 min. I would just mark 0.1622 x 12 or about 1.95 in , make your cut line and saw away. Check my numbers; good luck.

your right...i was sitting here thinking about it earlier and was having brain farts...but i got up and took a shower and figured it out on the steamy glass door with my finger haha...always have my best thinking time in the bathroom...anyway i will post pictures of the progress

doubleedge
03-28-2010, 10:08 PM
I found that 19 stones that are 12" by 12" would work best:

http://img13.imageshack.us/img13/5341/pavercircle.png

The outside radius is 36" at it's widest point; the inside radius is 24" at it's widest point.

I used a free program called Google SketchUp to create it. It doesn't make mathematical miscalculations.

AI Inc
03-29-2010, 06:07 AM
This is actualy a lot easier then it would appear. Take your outside # and divide it by # of peices. Take your inside # and divide it by # of peices and that will give you your angle.

DVS Hardscaper
03-29-2010, 08:01 AM
I'm gettin a kick out of that LITTLE hole was dug with a machine! Christ, it took more time to load and unload the machine than it would have for 2 of my guys to dig it :)

Gotta love white people.........



,

Dirt Digger2
03-29-2010, 01:49 PM
the little machine was also used to rip up the bulkhead board, dig the drain pipe line out from the pond, and move a pile of dirt...

but she sure is cute though

http://i942.photobucket.com/albums/ad261/dirtdigger222/Beach%20Work/3-21-10001.jpg
http://i942.photobucket.com/albums/ad261/dirtdigger222/Beach%20Work/3-21-10028.jpg

cet
03-29-2010, 06:05 PM
First of all DirtDigger2, you might find someone with a degree in CE from Penn State....
But since I always got a real kick out of your farming and dirt moving, I'll give it a shot.

The outer circle of the pavers will have a diameter of 28/3.14 = 8.917 '; the inner circle of the pavers will be approximately 6.917 ' and have a circumference of 3.14 x 6.917 =21.719 '. Dividing by 28 pavers, you have to cut back to 0.776 ' for each paver. You will take off 1.000 - 0.776 =0.3243 ' Now divide by 2 for each side and you have the tangent of the angle = 0.1622 or 9 deg 13 min. I would just mark 0.1622 x 12 or about 1.95 in , make your cut line and saw away. Check my numbers; good luck.

This looks like a pretty hard way to figure it out.

Only problem is 1.000-0.776=0.224 not 0.3243. 1/2 of .224 is .112

I think the answer is what I gave you in my first post.

capelawncare.com
03-29-2010, 08:14 PM
Looks like a long commute from Pa to that job...

Dirt Digger2
03-29-2010, 09:26 PM
that job is at my parents beach house...2.5 hours away...weekend work

doubleedge that google sketchup is really neat stuff...I use to use it a lot when i was a project engineer at a large road building company around here...not all that great for take off and what not but was a great tool to draw something in 3D then be able to show the crews what they were working on and what it would look like when it was done...put a 3D spin on the 2D plans....really cool when we built bridges and you could show all the rebar inside the concrete

i had some really awesome screen shots i made but when i left the company the computer stayed there

Dirt Digger2
04-04-2010, 07:58 PM
updates in this thread

http://www.lawnsite.com/showthread.php?t=297699&page=21

ajslands
04-04-2010, 08:05 PM
You used a mini backhoe just for that, seems like that would be a little overhaul but w/e.
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castle555
04-04-2010, 08:24 PM
Hey, nice job on the sketchup ,and other propeller-head answers you guys.

Dirt, you didn't say whether or not the flagstone is going to be mortared in place. if that is the case then you have to figure out the total width of how many 1/2" or 3/8" wide joints to subtract from the overall cut on each piece.
Since your 'set' is parallel you just need to use either inside or outside circumference. :hammerhead: