New videos twice per month! Archery education, physics and engineering all things hunting, archery, photography and videography relating to the outdoors. Subscribe for more, and visit me on instagram at @l.e.a.p._outdoors or reach out to say hi.
@@danielhoerig2649 check your print setting make sure it says print to actual size or scale at 100% because it’s small printing software likes to scale the image.
@@Lucas_Palmer_bownerd_engineer my printer app on my phone wouldn’t let me change it. Saved the file and emailed to myself. Printed from the laptop and all is good. Thank you!
@@danielhoerig2649 thanks for the update I’ll have to work on suggested apps for printing. my goal is to provide everyone the ability to print tapes. For some that might be library or Office Depot but still an option. Let me know if you have any other issues.
@@Lucas_Palmer_bownerd_engineer just printed out some sight tapes to verify what I had selected. This really helped me fine tune my metal sight tape. One suggestion. Give the option for tick marks every 5 yards as every yard is a little crowded. Also love that I can get the tape set up at my elevation and print another for the elevation I’ll be at in September!
If you can take a couple measurements for me I can add it to the app. I need the diameter of the dial which the sight tape is attached to. The second measurement is the how far 1 pin travels per a full rotation of the sight tape dial.
I have an HHA optimizer tetra the diameter of the sight tape wheel is 1.677, but it has a couple of tapes on it which are .0035 thick so it could be as low as 1.663. I can’t get it to do a full rotation but did half and the math comes out to 2.365 of pin movement for 1 full rotation. I also have an HHA optimizer lite ultra. The wheel diameter is 1.892 with 1 tape on it so it could be as low as 1.885. 1 full rotation maths out to 1.554 of pin movement.
@@benjamins7799 Thank you very much I added the features to the app, based on your measurements. Updates usually take a day or so to get approved, so you should be able to update tomorrow to version 2.8, which has these sight tapes. Let me know if they appear to matching up or not, hoping to get my hands on more sights soon to add as many as I can. Thanks again Side note if anyone has a sight they would like supported please provide the measurements and I will happy add them!
@@Jsfea01 spin rate does helps to balance out imbalance in the arrow system. Imbalance created by shaft flex, weight imbalance, geometry imbalance, shaft straightness, insert straightness etc. so ideally we want a rapid spin up. However, I have not gotten to the point of determining how much spin is necessary hopefully I can create some guidelines to follow for that. Surface area and where the surface area is relative to the shaft is the most important factor. Thanks for the question.
@@SWMissouriOutdoors I am working on the android version. Keeping the cost low by doing it myself makes it take longer. I am hoping a couple months to have it finished.
This pretty much confirms a lot of what we already knew. I’m really interested to see surface area vs surface area, like a long low profile vs a short high profile with similar surface areas. Keep up the good work! I might build one of these wind tunnel for my own arrow builds.
@@royleerobinson5 correct and change the value listed as “scale adjustment” listed on screen it will be a whole number. I also recently was made aware of a bug when switching between sights specifically from sport high to black gold/linear it does not like to update. However if you click on HHA or one of the other options then back to black gold it will update correctly. Working on a fix right now for that.
@@royleerobinson5 update is now live to fix that issue. Make sure to keep the app updated I add features often any problems please let me know. Take care, Lucas
Awesome! So i live in wyoming and setting up a tape out here is a nightmare witht the wind. Like 5 months ago we were trying to use a rifle ballistic app to do what you did in the video using ballistics indoors to get marks. Have you done more of that and what was your experience?
@@royleerobinson5 I have had a couple individuals try it with good results. However it is very sensitive and easy to be off it is more of a “bore sighting” get you on paper requiring fine tuning. However with the app it becomes unnecessary. You can use the onscreen or printed tape to set pin gaps. A buddy of mine just got a new bow we set it up in about an hr and we’re shooting 90yards without issue. We set the pin gaps to the linear tape option and matched a tape that came with his sight. For curved sight tapes like spot hog you would select a linear tape option to set pins and then Print the tape for the actual sight you are using fast Eddie black gold or whatever. He was hitting a little low at 20 made a slight adjustment and he was dialed from 20-90 with the tape and pins he runs a 5 pin slider. Does that process make sense? I have a bunch of videos I am in the process of making detailing how everyone can do this.
Also you can still do the ballistics method with the free or paid version of this app. You would select the pin you are trying to sight in for example 60yards as the zero, change one of the columns to drop and then shoot at one of the distances 5,10,15, 20 yards and hit the amount high listed on the drop column. However, it's much more accurate to use the sight tape section to set up your sight.
as an engineer, traditional archer and bowyer I find your videos excellent. it looked like some of your equations and conclusions were based on the assumption that arrow velocity is constant from 0 yds to 60 yds. not so - velocity and momentum erode downrange, with lighter arrows eroding faster than heavy arrows, hence momentum and penetration of heavy arrows win every time! see ranch fairy series.
@@bowhunter7922 hey great question no I definitely did not assume constant velocity, I actually built a ballistics calculator based on a study of arrow drag from the Japanese institute of technology which found drag coefficients of an arrow. Fom that I determined the drag per interval from launch to x yardage to determine what would be the downrange velocity. However, some discussion in the video is discussing the two most common arguments of today. Which are energy based penetration estimate vs a momentum based estimate. Neither are accurate which ED Ashby confirmed in his testing as well. I then used the poncelet model of penetration specifically a solution for a non deforming elongated rod to estimate penetration which followed much more closely with EDs results and others. Thanks for your question and support, take care.
Hi Trevor's just want to share a thought with you about a stable air flow and how u can achieve that,I saw this done on a tube video,they got a lot of plastic drinking straws together and placed them in front of there fans,when the air was pushed through them with the fan then the flow was stabilised hope this may give u something to try.also it's cheep to do if it works for u.cheers Rene from Aus
I don't know if you have a way of measuring, but it would be interesting to see the drag force applied. Especially when you get to testing different offsets, the related force during stabilization and after stabilization would be really cool to see!
@@C.Fowler the FOC video comes after this one. FOC Flight, Penetration and Buckling? Archery Eduction Video 4 all about FOC ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-uKjj2wqxoOU.html
@@loganchapman105 thank you will do! I realized too late after I posted that I never did that. It’s kinda like watching paint dry isn’t it. 🤣. Take care, Luc
Can I just ask, is your wind tunnel blowing air from the top or bottom? I can't tell from the video. The way the vanes are designed the wind should be blowing in from the top to play to their strengths, but I don't know if that's what's happening or not. Interesting video anyway.
@@thewhiskybowman the wind is blowing from top to bottom, many people had the same question so thank you for asking. More videos to come thanks for the support. Take care, Lucas
@@Lucas_Palmer_bownerd_engineer Thanks for the reply, I did have a look at the questions before posting and hadn't noticed that it had already been asked. Unfortunately I don't think youtube always shows us (the viewers) all the comments, which must be frustrating for content providers having to answer the same things over and over.
@@thewhiskybowman Its all good! I don't mind the comments with questions, it helps me to know what I need to explain more next time. I made that comment such that you didn't feel bad for asking since many people thought the same thing. It's a good question to answer multiple times makes the answer easier to find. You are absolutely correct RU-vid does not show all or even in order the comments. Sometimes I miss comments as well and I am supposed to get a notification for each one! Anyway take care and thanks for you support! Luc
Nice test. It would be interesting to see how a 4 fletch compares to the 3 fletch in stabilization. I don't know if you would be able to test this, but stabilizing with a fixed blade broadhead would be very good data for hunters.
@@Mr.bowbender I have a short video addressing this question. The fan is pulling air across the vanes so airflow is from top to bottom same direction as an arrow actually experiences. Thanks for the question you and many others have had the same take care, Luc
Awesome stuff! I guess the short arrows make the arm roughly same as in an actual arrow, but does the fact that the test arrows are rotating radialy about the point and not about the C of G or C of L, whichever it is, have any effect?
Yes absolutely rotation about the tip is different than how a true arrow behaves. Essentially this would be an arrow with 100%foc. However to compare fletchings it’s a fair comparison. I’m working on how to support the shaft from the cg while still allowing it to spin.
I wonder if suction from behind the arrow would be better than a blower from the front? Just thinking about the fan itself creating imperfect turbulence in the tunnel but suction from behind the arrow might create a more uniform airflow across the vanes?
@@Lucas_Palmer_bownerd_engineer oh nice! Did you chamfer and de-burr the intake tube’s mouth? Probably would make for very minor discrepancies either way but just throwing ideas out mostly haha
I’m working on it but probably a couple months learning kotlin and jetpack compose now. I hope sooner but just depends how long it takes for me to learn.
Great work Lucas. Have you considered a terminal velocity wind tunnel blowing from underneath. You would need to be able to vary the tunnel airflow velocity. Should give an estimate of vane drag.
Would love to see some of the more unique and quick fletch options like FOB, zinger and easy vanes(Australian based company, I think NAP also has something out they call easy vane). Also interested in which vanes are less effected by crosswinds.
Very interesting. Thank you for doing this. What I find most interesting is the similarity between vanes with similar offset / helical. What I'd be interested to see is same vanes with different offsets / helical. Perform this like a design of experiments (DOE).
Hey Lucas, As someone working in the aerospace industry with experience in wind tunnel systems, I wanted to share some insights regarding your data on vane damping times. While your data shows that most vanes have similar "damping out times" in the 10-second range, this might not fully capture the differences between vanes due to the nature of exponential decay in damping. Exponential decay typically involves a steep initial decline followed by a gradual leveling off, never truly reaching zero. While many vanes may reach a steady state within the same 10-11 second window, focusing on the initial 0.5-1 second could reveal more significant differences. The steepness of the initial decline in the curve might better indicate the vane's efficiency in stabilizing the arrow quickly, which is crucial for optimal performance. By analyzing the first 0.5-1 second, you can better understand the immediate damping/restoring forces each vane exerts, offering a clearer picture of their performance. This approach can provide more granular data on how effectively each vane stabilizes the arrow, highlighting differences that the overall damping time might obscure.
That is something I didn’t even consider thank you very much for the suggestion. I’ll have to re-evaluate this and try to determine this for future test! Thank you very much for the suggestion! Take care, Luc
@@Lucas_Palmer_bownerd_engineer I cant say for certain how much of a difference you will see but I think you can go back and look at the videos of all the trials you did and examine the first 1 second and see if there is any appreciable difference between vanes. simply take a measurement at the peak amplitude at various times and see which one has the strongest initial restoring force.
I've always wondered if arrows from a traditional bow are slow (~150 fps) enough to experience linear drag, whereas I assume arrows from a compound are fast enough (~300 fps) to experience quadratic drag.
So interestingly enough it turns out shaft flex is the bigger cause of laminar vs turbulent. Because traditional bows create a large paradox of the shaft they experience a larger drag coefficient roughly 2.6 where a compound bow with a shoot through riser and a stiff enough shaft has much less shaft paradox. If the arrow is stiff enough, and therefore the drag coefficient is lower at about 1.5-1.6 and experiences laminer flow The Japanese sports institute has shown this to hold true for Reynolds number up to 2.4 x 10^4. Very fast bows north of 320fps depending on arrow geometry or larger shaft flex the flow changes to turbulent and the drag coefficient increases to roughly 2.6.
Food for thought - The shorter the vane the total distance that a helical goes around the shaft is shorter. Logically, it makes sense to me that to get the same spin out of a 2" vane you need more helical than a 2.8". I like 1.5-2 degrees on a Max Stealth and more like 2.5-3d on a 2".
Interesting thought I’m trying to figure out the best way to measure spin rate. If I can figure out an accurate measurement I’ll see if I can test that theory. Thanks for the suggestion!
I tried a leaf blower the fluid flow pattern is extremely turbulent I have a larger fan now that will be much faster. The fan in the video is a 195cfm inline duct fan.
