# Could excel do this? **URL:** \ **Category:** Factual Questions\ **Created:** [February 17, 2018, 9:48pm UTC](https://boards.straightdope.com/t/could-excel-do-this/809021 "2018-02-17T21:48:23Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [February 17, 2018, 9:48pm UTC](https://boards.straightdope.com/t/could-excel-do-this/809021/1 "2018-02-17T21:48:23Z")
Input thickness .675" input Desired strain expressed in percents of deformation example .5% output Radius- ? I am guessing I might be in the 30" range Now the second part and not necessary but would be nice. Would be if you could feed the thickness in based on a taper and the program would spit out the elliptical shape needed. Other wise I could just figure how fast it graduates by averaging a few points. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [February 17, 2018, 10:34pm UTC](https://boards.straightdope.com/t/could-excel-do-this/809021/2 "2018-02-17T22:34:58Z")
To be clear, you have a rod of some sort (OK, let’s just call it a bow) of thickness .675", you want to strain it to 0.5%, and you want to know what radius of curvature that’ll bend it to? That’s a fairly easy calculation: The thickness will just be 0.5% of the radius. But that’s probably not actually what you want, because for realistic sorts of loading (like, say, a tension between the ends of the rod), you won’t actually get a uniform strain, and hence not a uniform radius of curvature. ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [February 17, 2018, 11:00pm UTC](https://boards.straightdope.com/t/could-excel-do-this/809021/3 "2018-02-17T23:00:18Z")
> [@Chronos](#): > > To be clear, you have a rod of some sort (OK, let’s just call it a bow) of thickness .675", you want to strain it to 0.5%, and you want to know what radius of curvature that’ll bend it to? That’s a fairly easy calculation: The thickness will just be 0.5% of the radius. But that’s probably not actually what you want, because for realistic sorts of loading (like, say, a tension between the ends of the rod), you won’t actually get a uniform strain, and hence not a uniform radius of curvature. We actually adjust the curvature of the bow while it is strained so that would work. I didn’t realize I could figure the strain that way, I was using a much longer method to zero in on it. That alone make it a lot easier. So .675=.995? Funny that gives me just what I came up with using a much longer method. So radius equals .675X100/.995. So thickness X 100/ strain? Would that be easy to program to excel? ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [February 17, 2018, 11:04pm UTC](https://boards.straightdope.com/t/could-excel-do-this/809021/4 "2018-02-17T23:04:25Z")
> [@Chronos](#): > > To be clear, you have a rod of some sort (OK, let’s just call it a bow) of thickness .675", you want to strain it to 0.5%, and you want to know what radius of curvature that’ll bend it to? That’s a fairly easy calculation: The thickness will just be 0.5% of the radius. But that’s probably not actually what you want, because for realistic sorts of loading (like, say, a tension between the ends of the rod), you won’t actually get a uniform strain, and hence not a uniform radius of curvature. So simply multiply .675X99.5 or whatever strain I am looking for. Much easier than I thought. I want to create a wound up band with slip clamps on it that I can simply stretch out to the desired radius I am looking at. ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [February 18, 2018, 2:12am UTC](https://boards.straightdope.com/t/could-excel-do-this/809021/5 "2018-02-18T02:12:14Z")
I modified the plan a little based on Chronos easier method of finding the radius. I was doing it the long by trial and error. I would be plenty close enough just moving my decimal point over two places on the thickness and using that as a radius. My new problem is that I want to convert my arch into a setting for a gauge. My gauge is a constant at 4" wide, it has a pencil that goes through the middle of it and marks flat spots in the limb as I run it across the limb depending on how far the pencil is protruding. I found a program online for calculating the radius of an arch but it does not go into the small size I need. I want to be able to put in the radius, the 4" gauge is a constant and then have it tell me the height of my archway or how high my pencil should be protruding. So If I know the formula for the radius of an arch program that is all I need. I am pretty sure I can find that. I found it, I just needed to scroll down a bit more for the formula, DUHHH.