Thanks so much - I have been looking on the internet for 2 whole days looking for how to make an octagon circle for a table. No one seems to realize how to do it!!!!

Awesome! Many thanks, this helps a great deal with the daughter's project =)

Or you could just take a piece of tracing paper, draw your circles, divide into as many parts as you wish, draw a suitable sized segment around each, measure one or make a template and make your wooden pieces on the table saw or bandsaw. Any medieval cathedral builder would have been proud to have you as his apprentice if you could have done that in fifteen minutes with five minutes to spare to thank god for having given you brains. ;-)

Very well done. Definitely helpful toward my calculation where I also need a specific chord length and remaining interior size while maintaining a specified ring width (t in your formula). Thank you

@projectreaDIY

2 жыл бұрын

Glad it was helpful!

You are correct but you explanation seemed over complicated to me. If you take the diameter of the ring and multiply it by Pi (3.14) you get the circumference of the ring. Divide the circumference by the number of segments you wish to use to make the ring. That gives you the outside length of each segment. The miter angle of each side of the segments is determined by the number of segments so that your ring is 360 degrees. So if you had 12 segments for you ring you would divide 360 by 12 = 30. You would cut each segment at 15 degrees on each side to have a total of 30 degrees. (Diameter X’s Pi [3.14] = circumference. Circumference divided by number of segments = SEL (segment edge length). Segment miter angle Must add up to 360 degrees.

@projectreaDIY

2 жыл бұрын

Thanks for the feedback -- if I'm following you, I think that calculation for the outside side length might yield a polygon too small to fit the circle. For example, for a 8" diameter ring divided into 8 segments: diameter * PI / segments = 8 * 3.14 / 8 = 3.14" side length. I plugged those same values into the Blocklayer site folks have recommended and it comes up with 3.31".

@jimwestmoreland4415

2 жыл бұрын

@@projectreaDIY Not sure why your program comes up with a different answer. I have been using the equations I described for 15 years or so with great success. I do segmented turnings and have made several dozen of them. There are some great programs available that you can design segmented turnings with. They do the math for you as well. Woodturner Pro and Segmented Pro are both very good in my opinion. Hope this helps.

@marinamkd

Жыл бұрын

This is actually brillint! I'm looking for a calculation that will help me make a ring (wreath) out of a pipe insulator, which looks like a pool noodle but it's hollow, so i cant bend it b/c it collapses. I sure hope that this will help me solve my problem 😻

@jimwestmoreland4415

Жыл бұрын

@@marinamkd should work fine. Remember Diameter x’s 3.14 (PI) = circumference. . Divide the circumference by the number of segments you want to use to make the ring and that gives you the outside length of each segment. Divide 360 degrees by the segments for the angle on the sides of the segment. Example [ 360 / 12 = 30] because each segment is angled on both sides divide the 30 degrees by 2 and you get 15 degrees. Make sense?

Awesome info...Thank you!

Great Video, Thank You!

This is a wonderful technique! Any recommendations on what process/tools to use after assembling the hexagon to cut out the circle? Would appreciate it.

I never thought I would have to use Pi in my life yet here I am and I forgot everything regarding this topic

As stated "Blocklayer" is the way to go .. and consider the angle to be cut .. 6, 8 or 12 sided polygons use a VERY easy angle to achieve. Most saws will have presets for these angles .. I did make a 7-sided polygon for turning a segmented ring, just to test the "joy" of finding the perfect 51.428 degree angle ... 30, 60, 22.5 are all MUCH easier to achieve.

Thanks for the great insite into octagons and cicles, curious, what if you want to add a 5 inch block into the octagon? Say 6 - 5" blocks into a octagon? How do you calculate the 16 side octagon for size?? Thanks for your thoughts!! I.e. 54" octagon, but with some different color block inserts.

@projectreaDIY

2 жыл бұрын

Can you link a drawing? Having trouble picturing what you are describing

I’m working on a circle nook seat, how can I get the information for a 36”-48” internal radius. The file was only able to few 24”. Thank you in advance.

@projectreaDIY

Жыл бұрын

If you enter the inner radius of the ring (say, 36"), the thickness of the ring (say, 12"), and the width of the boards you will be using (say, 15"), it will compute the number of sides, the miter angle, and the length of the sides. For these inputs, I get 8 sides, 22.5 degree miter, and 40" side length. Another alternative is to try the blocklayer website that others have recommended (www.blocklayer.com/woodturning-segmentseng.aspx). Good luck!

Thank you. Looks like this could be useful for table projects I’m working on. Still confused about why the height of the board is necessary. I’m just getting back into math after nearly 2 decades finishing HS. Only had 1 math course for my associates degree a decade ago, so the formulas are a bit complicated to figure out. Where did you come up with your formulas? Is there a source you can recommend where I can learn to create my own formulas, such as books, manuals, videos, courses, etc.?

@projectreaDIY

2 жыл бұрын

I went through quite a bit of scrap paper trying to work out the answers and ended up with the wrong formulas a few times before eventually (hopefully!) landing on the right ones. The math is mostly trigonometry -- angles and triangles. This is a resource you could check out on trigonometry: www.mathsisfun.com/algebra/trigonometry.html.

@mavenfeliciano1710

2 жыл бұрын

@@projectreaDIY I guess trial and error is the best teacher. I made a few decagonal, but when I did it again I had to reset everything. I kind of rushed it and the first one that day was off by about half a degree. I wasn’t satisfied, so cut it again but by the time I got it it was slightly short. Now I know not to trust a setup blocks. I have a good compass angle tool but I couldn’t find it at the time. Best thing is make sure saw is square and accurate, leave it at 90° and use a block that is at the angle clamped to offset the 90°, and make a test cut checking for dead on angle. The block makes it quicker than constantly changing angles on the saws, especially if your your using different saws and some positive stops are accurate. Now with the angled block I can use miter saw, table saw, or other tools to do the job.

Perfect can I get a copy of this excel sheet ?

@projectreaDIY

2 жыл бұрын

I put it on Google drive and posted a link in the video description. Please let me know if it doesn't work and I'll find another way to get it to you.

@Keran3468321

2 жыл бұрын

@@projectreaDIY Thanks alot