Arrow Builder Spreadsheet

[Bump79]

Over the years I’ve developed a fairly comprehensive database/arrow builder and figured I'd polish it up for people to utilize and noodle what you’d like for your build. The database has as many vanes, nocks and arrow shafts as I could find. It's not complete of course but will be updated live. It's fairly straightforward but feel free to ask if you have questions.

Arrow Builder — The Arrow Builder

www.thearrowbuilder.com

How to use:
1) The sheet shown below is a live document on Google Sheets. It works best on desktop. Being a live google sheet multiple people can be in it at any time, which would be frustrating to use if someone else is in it. So what I recommend is doing a File->Download as XLXS for Microsoft Excel. If you don’t have Excel, then click File->Make a Copy.
2) Starting from Cell C9 work your way down the sheet, completing information as needed. Lookup functions will populate based on your inputs. For example, when you select your arrow shaft and spine, the GPI populates. Same for vanes, nocks, etc.
3) This sheet allows you to compare 2 arrows and shows the % difference between them for reference.

 

[Bump79]

Some handy stuff - if you want to find a certain shaft within a criteria you can use the Arrow Shaft Data worksheet. Filter to your spine, then sort by light to heavy or use a filter to select what your GPI range you'd like. You could also filter by inside diameter for the shaft size.


Another use - Say you want to know what you're options are for hunting vanes that are greater than 2" in length and greater than .5" high. Put a filter in and then you can sort say weight low to high. Then you've got a pretty comprehensive list of vanes available to you that would meet you minimum criteria.

 

[Mighty Mouse]

Nice spreadsheet.

One simple modification I would suggest to make your speed/KE estimates more accurate at heavier arrow weights would be to use a fixed KE assumption (instead of a fixed rate of speed change of 1 fps per 3 grains). KE actually rises slightly with increasing arrow weight, but assuming it remains constant will get you very close. Using 1 fps per 3 grains will significantly underestimate speed and KE at heavier arrow weights.

For example, starting with the default values in your spreadsheet and adding 200 grains to "Build 1" (678 gr TAW) predicts 217 fps/70.5 ft-lbs KE (which is too low). If you instead calculated KE at your corrected IBO conditions (350 gr @ 326 fps = 82.6 fps) and used that KE value to calculate speed at 678 gr, you would get 234 fps, which is much closer to reality.

 

[Bump79]

Nice spreadsheet.

One simple modification I would suggest to make your speed/KE estimates more accurate at heavier arrow weights would be to use a fixed KE assumption (instead of a fixed rate of speed change of 1 fps per 3 grains). KE actually rises slightly with increasing arrow weight, but assuming it remains constant will get you very close. Using 1 fps per 3 grains will significantly underestimate speed and KE at heavier arrow weights.

For example, starting with the default values in your spreadsheet and adding 200 grains to "Build 1" (678 gr TAW) predicts 217 fps/70.5 ft-lbs KE (which is too low). If you instead calculated KE at your corrected IBO conditions (350 gr @ 326 fps = 82.6 fps) and used that KE value to calculate speed at 678 gr, you would get 234 fps, which is much closer to reality.
View attachment 820181

Good catch - I was actually working on this when you commented. I developed a simpler calculator without as much detail and created a new formula based on actual chronograph data from varying draw lengths, draw weights and arrow mass. I've updated the google sheet to match.

Let me know if it jives out for your chronographed data!

Arrow Speed, KE and Momentum Calculator — The Arrow Builder

Many online arrow/bow speed calculators use an oversimplified calculation to determine arrow launch velocity. This results in inaccurate results, especially at higher grain weights. Increasing arrow mass always will lead to marginal increases in KE, meaning the bow gets more efficient as grain wei

www.thearrowbuilder.com

 

[Bump79]

One thing unique thing I did in this calculator was add a calibration tool to adjust your IBO to get more accurate speeds.

Here's an example -
1) Find a bow test of your make and model bow.
2) Enter all your bow data at the testers spec, in this case 30", 70#, 336 IBO and a 350 grain arrow to compare to IBO.
3) Use the derating slider at the bottom to calibrate the advertised speed to the their real world speed. Now you've got the KE baseline set properly.


Then you can increase the mass and get closer to real life speeds. If you watch the video - he tests 450 and 650 grain arrows next. This calculator pretty accurately predicted the arrow speed.