Any excel experts?

[Badger]

   I have a small program I would like to write. A computer generated radius that represented a specific strain based on limb thickness only.

  Input- limb thickness
  Input- Desired strain expressed in a percent  (EXP .5%)
  Output- Radius needed

  Could anyone here do this?

   tool to go with it, You could take a coil and wind it up with sliding bands and then simply adjust it to the radius you are looking for and just hold it up to the bow,

[DC]

If you can get it sorted you could calibrate a Gizmo with it

[k-hat]

I'm not all that on excel, but I could spin you up a quick free webapp that'll do it if you're interested in sharing it with everyone else 
I'm sure we could put our heads together for the algorithm.

[k-hat]

After reading y'alls thoughts on the other thread, I wonder if setting up a database would be handy where people could enter their figures and keep running averages for each species.  It would be cool to see what the community comes up with.

If you are interested in setting this up as a web app, i would enjoy getting something up, maybe with simple log-in, maybe without.  Maybe we could put a sticky with a link to a secure-ish automatic login that would keep it away from the general public.  Lemme know if you want to do this!

[Badger]

  The formula is simple, multiply the thickness by the strain example. .375X99.5 = 37.3 radius. You would be close enough just moving the decimal point over 2 places and using that as a radius.  You could easily make a set of gages going from .300 to 1.0 in increments of 1/2". It would not be a precision gauge but a nice visual aid.

[Badger]

After reading y'alls thoughts on the other thread, I wonder if setting up a database would be handy where people could enter their figures and keep running averages for each species.  It would be cool to see what the community comes up with.

  For me personally I have no interest in trying to determine thicknesses. I prefer to do that while building the bow. My interest is in making sure whatever thickness I have does not get bent into too tight of a radius. I hope you can follow that. Your radius gauges would only need to be about 5" long. I just thought of a way to use the gizmo as a precision measure device. Get back in a few minutes

[k-hat]

Ah, gotcha.  So would you prefer this as an excel sheet or online page?

[Badger]

   I just checked out an online calculator for radius of an arch. We use this quite a bit in the construction and drapery business i was in. The arch in the case would be the gizmo, the program would simply give you a setting for the gizmo as far as how far the pencil would stick out on a 4" gizmo to give a specific arch or radius.

  So the 4" gizmo would be a constant, the input would be the thickness which creates a radius by moving the decimal point 2 places. The output would be the height of the pencil lead, anyplace it did no mark you would have to not scrape. Now the one problem I see is that we seldom mark our bows at full draw usually about 2/3 draw in my case. Si it would have to be calibrated for a 2/3 draw and this is what the bowyer would have to pull his bow to for marking.

[k-hat]

Ah, that sounds like a cool idea.  So would that be a linear relationship to adjust for the 2/3 draw?  ie: strain percent would be 2/3 * 99.5 or essentially 66.3?

[k-hat]

so essentially we want an algorithm/formula where the user can plug in the thickness of the limb and get the setting for the gizmo, yes?  I can put that together. My wife can help me set up a spreadsheet, or I can put a calculator online as mentioned.

[Badger]

  I found a calculator on line that will give me the exact figures I need it is called radius of an arch. I need to convert it to excel so we can pass it around. For example a .55 thick limb would have a 55" radius in the bending area, this would equate to the pencil protruding from a 4" gizmo by .168 for example. Depending on the treads you are using in the gizmo you turn the pencil x amount of turns and portion of turns to get an exact setting.

[willie]

the program would simply give you a setting for the gizmo as far as how far the pencil would stick out on a 4" gizmo to give a specific arch or radius.

Sounds pretty simple, Steve, if you know what strain you need. Would there be a way to adjust strains for different species wood?

[Badger]

  I can send you a link for to the formula if you send me your email

[k-hat]

I may nerd out on this one and create a calculator with presets that are customizable (eg: draw length and max draw to figure the proportion of draw and the resulting radius, etc) and make it available online for PA folks if that's ok with you.  Might can even bribe my wife to help me set up an excel sheet and make it a 2fer 

[Badger]

K Hat, I would love it.