Hello, im a machinest working on a personal project, machining a decagon. Ive found the length of the flat using the same formula you displayed here. How would I go about finding the rest of the length of the doted line to the edge of the circle?
If you mean the length in the centre between the cord length and the arc length of the circle you would need to find the length of the height of one of the right triangles I drew (the dotted line in the triangle). You can use the cosine trig function to do so. Once you have that length, you simply subtract it from the radius to get the length between the chord length and the arc length (in the centre). I hope this makes sense.
In the example I did with the 5 equally saved holes in a 4-inch diameter circle, the height of the right triangle would be: h=4(cos 36 degrees) = 3.236". Subtract that from the radius: 4" - 3.236" = 0.764". Let me know if you were asking something different than this.
@@mathmadeeasywithlaurel9353 thank you, the day after watching your video i figured it out. I was drastically over thinking it. My project turned out to be perfect. Everything was pin point accurate.
D= 2r sin(180÷5) D= distance . R= radius . D = 2r sin(180÷5) This formula can be solved for any holes pattern on a circle?? Calculator : 2×4.00 ×(180÷5)sin= 4.7022.
Yes it does work providing you replace the 5 with the number of holes on the bolt circle. In other words, D = 2r sin(180/#) where # represents the number of holes.
You can still use the formula given in the example. But when you know the chord length and not the diameter, you will know the "x" in the formula (1/2 of the chord length), which is the numerator, and you will be finding the radius of the circle, which Is the denominator in the formula. If this doesn't make sense let me know and I can give you an actual formula for the radius or diameter.
Just used this formula for a three hole pattern! Turned out perfect thanks!
Good to hear!
Short and sweet, thanks!
Hello, im a machinest working on a personal project, machining a decagon. Ive found the length of the flat using the same formula you displayed here. How would I go about finding the rest of the length of the doted line to the edge of the circle?
If you mean the length in the centre between the cord length and the arc length of the circle you would need to find the length of the height of one of the right triangles I drew (the dotted line in the triangle). You can use the cosine trig function to do so. Once you have that length, you simply subtract it from the radius to get the length between the chord length and the arc length (in the centre). I hope this makes sense.
In the example I did with the 5 equally saved holes in a 4-inch diameter circle, the height of the right triangle would be: h=4(cos 36 degrees) = 3.236". Subtract that from the radius: 4" - 3.236" = 0.764". Let me know if you were asking something different than this.
@@mathmadeeasywithlaurel9353 thank you, the day after watching your video i figured it out. I was drastically over thinking it. My project turned out to be perfect. Everything was pin point accurate.
@@joshualawson4326 that’s fantastic!
D= 2r sin(180÷5)
D= distance .
R= radius .
D = 2r sin(180÷5)
This formula can be solved for any holes pattern on a circle??
Calculator :
2×4.00 ×(180÷5)sin= 4.7022.
Yes it does work providing you replace the 5 with the number of holes on the bolt circle. In other words,
D = 2r sin(180/#) where # represents the number of holes.
Is there a formula to figure out bolt diameter with just chord length?
You can still use the formula given in the example. But when you know the chord length and not the diameter, you will know the "x" in the formula (1/2 of the chord length), which is the numerator, and you will be finding the radius of the circle, which Is the denominator in the formula. If this doesn't make sense let me know and I can give you an actual formula for the radius or diameter.
Yes this makes sense. Thank you so much this is gonna help me out tremendously.😊