Introducing Recurve Riser Flex Testing | How I Will Test Archery Risers with REAL DATA
Вставка
- Опубліковано 15 жов 2024
- I am VERY excited to share this and debut recurve and barebow riser flex testing. Finally some real hard data on how risers are flexing while shooting them and I explain why this is arguably more important to every day backyard or club level shooters than seasoned pros.
Excuse my throat clearing and sniffles, still recovering from Covid and was too excited to share this experiment to wait any longer.
Keep in mind that even though the lasers showed 3-5mm of moment of flex, due to parallax with the measuring paper being ~30" away from the riser there is very little movement of the actual riser itself. This was just a great way to illustrate and explain what I am looking for. This will also be very repeatable and I will be able to share data for many different risers for the public to decipher and interpret as my database grows.
Consider Supporing my Channel
UA-cam Membership: / @jakekaminskiarchery
Check out my website jakekaminski.com for the many ways to support my channel; Books, Apparel, Patreon, Digital Coaching and more!
Check out new Apparel:
www.zazzle.com...
Support this channel on Patreon:
/ jakekaminski
*Send Cool Stuff To:
Jake Kaminski
P.O. Box 742
Micanopy, FL 32667
Social media links:
/ kaminskijake
/ jake_kaminski_
**Disclaimer: Jake Kaminski participates in the Amazon Associates Program, Links to amazon.com or amazon businesses and advertising fees are given to the owner of this channel. Affiliate links are helpful to this channel, and is a way for you, the individual to contribute to this channel by clicking on links and doing normal amazon shopping (without spending any money outside of your norm.)
*Items sent to my P.O. Box cannot be returned. - Спорт
That's a good start, Jake. Some baselining measurements are in order as you continue: Run each experimental iteration a number of times (three to five, I think) to assess the precision of your measurement technique(s).
Report your results in good statistical form (average results with standard deviations, at a minimum). Somewhere along the line, try to get data from three identical bows to assess the bow-to-bow variations in what you are measuring. This will help when you or others explore how one type of bow varies from another.
For example, if manufacturer A bows vary from manufacturer B bows, be sure that variations from bow-to-bow within a manufacturer's bow-making process are not of the same magnitude as variations between different bow designs.
Pulleys are designed to use particular diameter ropes; get a better pulley and use the rope dimensions specified for that pulley. This will avoid rope jam issues and allow smoother draw operations.
You can get free blank graph paper by "Googling" graph paper on the Internet. Print what type, dimensions, and quantity that you need. Graph paper, as you pointed out, may make measuring and reporting your results more graphic and more easily understood..
Your enthusiasm shows; keep up the experimenting (and the UA-cam demonstrations). Good data trumps gut feel and street lore any day.
Michigan Dave
Cheers Dave. I planned on 3 minimum measurements and tests to be sure. I have two ATF risers currently so I will see at minimum if those two are different. Ordering 3 of each riser to test could be costly and Im not sure manufactures will send me 3 of each.... BUT that's a great idea and I have wanted to know that answer as well. Imagine shooting a bow for 3 years and then measuring against a new one....
Finally somebody who can test risers not just based on the feeling after the shot! You are the first one in history testing something like that on recurve bows. It's absolutely amazing! We appreciate so much your passion and willingness to discover and test anything about archery. Thank you for your efforts Jake
Cheers
Congrats on your (just over) one-year anniversary with this channel. What a fantastic resource you have created for the archery community. Thank you !
Cheers. Lots have changed!
This puts a whole new dimension into setting your bow up for tuning and centre shot, love your passion in Archery Jake, you have found something here that most of us would never have though of.
I can fully understand your excitement ... data-driven is fun but also useful as it remove bias. Also enjoy to see you learning as you go.
As for suggestions I thought about to
1) make a frame to hold the paper on the plate top/button and have the paper horizontally moveable during multiple measurement for the same setup (require maybe preprinted grid on the paper)
2) fix the phone to capture the image on the riser-side of the long rod (or use a 8-12 MPixel USB camera); that would give you consistent images in case you want to overlay them between risers.
3) when you asked for the micro adjustable laser setup my first thought was: Beiter Plunger ; but no further idea how to integrate that plus a bit expensive ( ask them, they might send you two)
Looking forward to see more and how the process evolve
Don't forget your stabilizer is about 4 inches below the centre of the riser that will flex the end of the stabilizer down so both top and bottom are flexing the same 'ish'
Excellent! So cool to see a new level of info being brought to your reviews. Been seeing your teasers for a while on Discord, awesome finally seeing it all come together!
Wow! I’ve always heard and thought about this, but have never really seen true proof of it. Congrats on finding a solution to show this. I’m honestly amazed. Can’t wait to see more!
Thanks!
Your only at the tip of the ice burg I think. I applaud you on your approach to a very technical issue.
First I would like to thank you for all the videos you have given us. Information like you have shown us has been almost impossible to find and to have it in one place is a gold mine.
Only thing I would check is the possibility of the limbs moving or not perfectly aligned in the limb pockets. Reason is you are now comparing engineering vs eyeball measurements.
I'm as excited as you on your quest to measuring riser flex. I'm looking forward to seeing where you end up as your testing evolves.
Thank you from the bottom of my limb bolts...
Great idea. Carbon bows v aluminium could be interesting. Great work.
Thanks for doing it. 😀
This is great to see. I’m frequently surprised/ perplexed that manufacturers don’t use hard data more, I’m tempted to think that marketing is more important than facts. I can’t imagine the industry will support your efforts in this but it is a brilliant thing you are doing. I hope the grassroots archery community supports you financially to allow you to maintain your inquiry. I do think your setup can improve, there are some good comments so far, there will always be a cost to improving precision and methodology but please keep at it, you are onto something good here.
Thanks!
It's so awesome you take your "haters" in positive way and develop a way to check/prove your words. Great video again Jake, thank you!
Always!
Solid data incoming! Great that someone with several bows can check it independently! Keep on going!
Thanks
I couldn’t find a link to this data set. I’m really excited to see it!
Debunking 30 years+ of marketing with facts based method... Love it!!!
Thats my motivation!
Jake, this is an excellent initiative; the bow manufacturers will probably hate you but us archers won't! Some ideas to maybe improve the set up: the distance between the bow and the paper is short meaning the indications of deviation are quite small, introducing significant inaccuracies whilst physically measuring them. You could improve this by increasing the projection distance, so set the paper on a wall say 5 or 10m from the bow. You could also create a single point reference by inserting the cross hair laser (set vertically and horizontally) in that arrow (constant centre point) and then taking the measurements from that projected reference point. By doing so, you would not need rely on the riser remaining vertical throughout the draw as you are measuring relative deviations. Keep up the good work.
I tried the wall as a longer distance, but because I am measuring from 3 different points on the riser, as the bow rocks and moves during the draw cycle the 3 points change their position on the wall because they are not zeroed out in space, they are zeroed to each other. I tried that and found it impossible to isolate the movements relative to each other. I could try a longer stabilizer potentially. or screw two together to double the distance measured.
Thanks for the comment!
@@JakeKaminskiArchery It would only work if you have a zero reference point from the bow itself -that's why I suggested putting a cross hair laser inserted into the arrow tube and measuring everything relative to that point. All bow movements from the draw cycle are then eliminated. Did you try that?
Would it not be the same as just using the arrow dot as the central reference point and then measure the movements of the rest from there? I may not be understanding what you are meaning.
@@JakeKaminskiArchery Yep exactly that. The arrow dot (or cross hairs intersection) should be the centre, then everything else is relative to that point. Worth a try.
Scratch the arrow laser idea - not safe. The centre laser also needs to be fixed to the riser
Hi Jake!
Pre-print your sheets on the stabilizer. 3 crosshairs in a left to right 45degree angle.
Botto on bottom left crosshairs
Middle on middle crosshairs
Top on top right crosshairs
It removes confusion for each Mark
It gives each mark its own consistent space
When you start getting an idea of average deviation you could start pre printing small fine grids with small fine lines, like 1-2pt lines
This will also help with marking consistency and data recording
Put a few lines tor testing data
Riser name, date, time, temperature, humidity %
String configuration (material, strands, nocking point from top and bottom)
Brace height
Top & bottom tiller
String length
Great ideas
Few concerns I want to point out with the rig system which I have spent some time putting pen to paper figuring out my own rig.
1. Putting the diodes on the sides of the limb pocket is assuming the sides are on a flat parallel plane to the vertical center of the riser, and does not have some small tapper in the design. While the setup works for flexing, unless you assure it's on a parallel plane it will give you false positive on torque.
2. Nock point position should always be measured as this can cause an offset on which limb gets pulled "more". For consistency it should be on same plane as the plunger button for all risers.
2a. The distance of the plunger button to the top and bottom limb pocket should be measured for reference.
4. The same limbs should be used on all tests. That means you'll get different results when you test Hoyts and their formula limbs. Limbs sold in pairs have slightly different tensile strength and one is slightly less than the other. That's why they're marked top and bottom (this was confirmed to me by a manufacturer). You would be better off pulling straight from the limb pocket without limbs if you want to measure flex and torque differentials.
As a side comment I would like to see how much difference (if any) there is in flex if there is an offset (if I put more pressure above the nock or below). How much human inconsistency error is needed to see changes in the riser flex. Isn't this factor what makes a bow more forgiving and in turn consistent?
Hey Jimmy,
Thanks for taking the time to comment!
1. I agree and is why I have changed to measuring off the back of the riser between the limb bolt and the dovetail, this way it can be consistent even on formulas... Also they are all now on the same plane too.
2. Agree 100% I will keep that the same too
2a. Agree and I take it a step further now measuring the laser to target distance difference as well and correct my measurements for that difference too.
4. Agree 100% and will do that as well.
You'll see what that does in the next video coming out tomorrow. I pull the bow back and show the human input in the next video.
dude you are a silver medalist... twice! if thats not high level shooter i dont know what is ... definitely calling yourself club pro level was wrong almost a insult... . my real comment i was waiting till the end of the video to make until i felt complied to tell you youre a high level shooter was that i enjoy nerdy stuff like this id like to see this be worked in to bow reviews.... thank you for putting your decades worth of experience and knowledge on youtube for all to see . this is way above my level but im excited to learn the differences in bow flex in individual companies and riser designs ... im rambling but anyway " excuse my giddyness" ;)
Exciting data. You mentioned that adding weights to certain areas could make the riser flex differently and that this can influence how your arrows group. Would you be able to get data on how weights on the top (near the arrow rest/plunger) or the bottom (near the bottom limb pocket) impact the riser flex? For barebow archers, would this be a way to measure optimal (most forgiving) weight setups?
The added mass would only make a difference on release. With this test there is no release, only the flex at full draw is being measured. What this test does seggest, is that if both pockets flex evenly then the pocket with more mass would return to original postion slower. How much slower is anyones goess, I would say probably not noticable unless it is a very large difference.
Great experiment. May be worth collating the vertical measurements from the button to the grip and laser positions. May explain some of the point movements in the future.
Hi Jake thanks for another great video.
My idea is that you can print some measuring grid sheets i think it will make a little bit easier and consistent.
Check out the newest video on this testing: ua-cam.com/video/sxMRPhRETrA/v-deo.html
That's really cool Jake! Would you consider the pressure point in the grip, which is almost always lower than the pivot point to be important in these tests? Maybe you could make a sort of hand substitute to hold the riser with?
Very interesting observation...thought since it's a solid base that the limbs would be the only thing flexing. I bought your book to learn more. Thanks Jake 🤗
Can you show using next video in how you would shot traditional bow as well. Merry Christmas to you and your wife.🎄
Just brilliant, really keen to see how different brand risers behave under the exact same conditions 😁🏹
Me too!
Very interesting and great work. Suggestion: try the set up and measurement multiple times on the same riser to find the inconsistentcies in your protocol. The measurement is essentially change in angle which is nice way to visually amplify the tiny riser deflection. But it means tiny changes in set up could have large impacts.
Agree. Thanks for the input.
Now this is some next level shit. And your findings correlate very well with how the specific riser feel in the shot. Stiff in the bottom, softer around the sight mounting area.
Crazy for sure!
A valid test, well done! The drawing of the string at the nocking point will of course pull the centre laser up as it is pivoting about the centre of the bow (is the grip the centre of the riser? Usually not). Simple calculations show that the ends of the riser are moving over 1mm each - a huge amount!
Thanks! I have a jig I made to draw the bow back with 3 fingers so that will be fun to try.
Excellent content, always interesting to watch! Tiller should be 0 and limbs should be aligned, correct?
Idea: cut the arrow exactly on the mark you set and have it fall of the bolt to measure the draw length, should be more exact
Hi jake, just wanted to let you know that I am as excited as you are. I think what you are doing is critically needed with new risers pumping out lately and the review criterias always so subjective.
On the critical side, I am not sure if I am right but I saw the starting point of lasers to be not in plane with the arrow(or center of the bow). Instead, it is off set to the left a certain(and possibly arbitrary) amount. I think it is important to make sure that the starting point is in plane with the geometric center of the bow or off set to the left a fixed amount everytime to not have trignometry render different results uncompareable between risers.
Why would it matter? I am trying to wrap my head around why. As long as they are mounted in the same areas, and reference to the same place on a static object attached to the bow ( the card on the stabilizer) It shouldn't matter.
If the bow pointed to a static object not tied to it (the wall) then I would assume you would be 100% correct.
@@JakeKaminskiArchery Let me provide an hypothetical example. Say you point a laser perpendicular to a wall, rotate it 3 degrees to the left, the dot moves 1 inch to the left. Then at the same distance to that wall, the laser starts by pointing 30 degrees to the left, then you turn it 3 more degrees to the left, the distance that the dot travels on the wall will be way more than 1 inch. I am exaggerating the scale but I hope the analogy is helpful.
Curious to see the carbon riser compared.
Nice job as usual, Its really a good idea. What worries me the most is the lateral or horizontal flex because it's generates forces that are not in line with the path of the string. Big hello from Brussels Belgium.
Really interesting, never realised it flexed that much
number data is fairly hard to gather for most archers >_>
This is awesome!!!! You actually did it!!!!! :D
I'm certain you still have your W&W TFT, can you do that next? Then the rest of your (likely huge) collection of risers? :D
You have a fairly good setup. I suggest using a .1 mm pencil :) [and finer lasers, if those are even available lol]
Maybe use fine grid graphing paper for the paper?
I'm honestly excited.
I'm certain being you, you have a huge collection of risers & limbs :)
Maybe do what I do and commit sacrilege by mixing your Hoyt/W&W risers/limbs lolol
Then you can do multiple regression analysis on whether mixing risers/limbs are bad or perform less good, or maybe you will find that a particular mixture of limbs/risers work great together. The boring result would be that you should use the limbs the manufacturer of the riser released at the same time because they were tested and optimized for each other during testing.
Jake that's fantastic to watch ..Would not that the riser would move that much around the the handle ..Also so see results that clearly is also great..If you can show how the risers have got better over the years or not ..Again great to watch and a big thank you for the work you have put in to this . Good to see are really in to it ..As long as you don't up set some companies. .Thanks buddy ..
Cheers.
What I meant to say was that I wouldn't have thought that the riser would move that much around the grip ..Hope this makes more sense. .Thanks again Bud ..
Got it. Thanks for clarifying.
Brilliant test. Thank you Jake. I've always had these theories in mind
Glad im not the only one.
I'm wondering if the central dot movement is because the pressure button is about ½ - 1 inch above the pressure centre of the grip, and also you have removed the grip, meaning the pivot point of your jig is forward of where it would be if you left the grip in place.
Very interesting. I'm wondering if flex could be used to increase speed of the riser by altering the plane of the limb pocket relative to the increase of the deflex, ie, I expect the plane angle to increase relative to the vertical, but if the riser can be made to flex in opposition through the use of crossed members in the riser and greater rigidity in the back of the bow relative to the front. The Gray AIX seems to achieve this, whereas the Spigarrelli Revolution increases more than average, but very consistently.
This is brilliant! Would be good to see the results from different limb alignments too. I'm also wondering about effects over time - long 30 second hold versus 'snap shooting'.
Yes, all things planned....
Take it to the next step and compare a riser that has been shot 100,000 times vs one that's new.
Hi Jake, I admire what you trying to achieve with this video. Very interesting testing. I however have one issue: since you had the bow on a drawboard and did the full draw the same as with a compound...I feel that there may be a error in this test. Please correct me on this statement if its wrong: The angle the string makes from top limb to arrow nock will differ from the angle from the nock to the bottom when at full draw by an archer. This may cause a variance in your results if you use the values from the drawboard machine.
For the arrow maybe this product would be great: GRG Archery Laser Sight Tool for Bow and Crossbow, 223 Bore Sighter Shaped (on Amazon.com)
Kindest Regards
I would remove the center laser, because it is too close to the stab mount, in my opinion it gives more noise than information. Also I think it is better to relate it to draw length, because risers may have different limb mount pre-load. Keep the same limbs for every test, as the limb behavior may change. It is also important to know the stabilizer length, or the test measured length, so a 1mm dev on paper translates to how much flex? Very important to compare apples. I think this is very good trial!!
Agreed on all accounts, just a work in progress. Will finalize tests before posting hard data sets.
I would love to see the test done in the heat and cold on the same riser as it would be good to see how the weather can affect it
Hi Jake. Very interesting video! Some thoughts: does the riser flex in the grip area (thinnest part) or in the pockets areas or it all? At what poundage does it begin to flex? Do the manufacturers test the max poundage limit before the riser breaks? Keep going. Next step: Does the riser flexibility remain constant over time?
14:05 that scale seems obnoxiously pleased with itself...
Totally loving this and also finding that I'm not the only one who finds themself getting obsessed over the details! Love it!
Something I'm wondering about though, and it's hard to explain on here so my apologies for any up-coming confusion: If you pull a cork from a bottle of wine, as you exert force on the corkscrew, there's a tendency to twist the cork out as you pull it due to natural wrist movement/arm extension. With that thought in mind, is there, whilst the bow is being drawn back, a possibility of lateral twist being introduced as the force and distance increases?
If there is, then my thoughts would be that it could potentially come from tolerances within the manufacture of the limb pocket, or the limb itself (or possibly the string connection? I've had occasionally had bow scales slip on the string when pulling back). That wouldn't negate the results of any tests on a specific setup of course, but if the riser is torquing because of uneven pressure being applied due to a slightly angled limb, does that alter the attribution of cause? That is to say: Hypothetically, yes, this riser and the material it's made from are flexible at 5% but, that 5% is the pliability of the material and the actual deviation of 'my riser with these limbs' whereas for the same riser it could be 10% or 0% depending on how the limb is fitted or designed?
Put another way, is it possible to conclude that the 'Acme GT Turbo' riser has 5% deviation or, could that deviation vary across risers of the same model depending on other components, and their manufacturing tolerances?
Does that make sense?
It somewhat makes sense here.
If I repeat the test with the exact same nocking point pulling location, same tiller, same limb alignment, same everything then however the risers flex should be comparable.
I will make a different peg some day that the grip sits on to simulate hand pressure on the grip and already have "fingers" made to draw the bow back to see if that changes anything.
@@JakeKaminskiArchery Yep, I think it should work and if anyone can make it work, it's yourself. What had worried me I guess, was what information the results were telling us. Everyone is looking for an edge and there's a temptation to think that hypothetically if you got a result of say 5% distortion with 'Riser X', if I go out and buy 'Riser X', I'll have bought a riser that has only 5% deflection.
My concern was that I don't think that assumption would follow. The results would be correct and consistent for you and therefore valid comparatively, but they'd be specific to your setup and perhaps not reproducible for someone else with different limbs, etc. Of course, if someone made that assumption that would be their fault, but it could be something to factor in.
@@JakeKaminskiArchery I've just had another thought, sorry to overload your notifications:
but, maybe what you are onto here is actually a marketable product/accessory for a bow press? My concern was essentially whether your results would be persistent in my own setup and if something like a misaligned limb or limb pocket would alter the results.
If it did, then what you might have is one heck of a more accurate replacement for Beiter Blocks? If you could print out the components and parts, tie in with a bow press manufacturer as an accessory or built-in part, could this be the perfect way to set up a bow? Literally, at an Olympic level of accuracy!
All the best with your endeavours!
I absolutely love this Jake, I’v been thinking of this for a while now. There are how ever many factors to take into consideration.
My first thoughts will be.
If the limbs are micro aligned, should these measurements be started at 0% tiller, should the graph be on a fixed point on the wall not on the long rod, as the riser flex’s then the long rod will also move too.
The riser should be held in a fixed position that replicates the hand grip as there will be different pressure points.
Is the pulley positively lined up with the string and bow.
I think that the hook you’re using should also be replicated in the same shape as the three
Sorry sent message before I had finished.
I think that the test should start with all components set to zero brace height, tiller, limb load ect ect.
Then test at manufacturers settings. This is very exciting 😳 as many people have said already carbon v aluminium risers.
But there are so many things to consider in the tests.
Can’t wait for the next test 👍
Oh and by the way Jake, bottom laser break in the right hand side is due to the long rod, but I’m sure you had worked that out yourself.
Keep up the great work Jake
Merry Xmas 👍😎
Thanks for the comments David.
I have to have it mounted on the riser via the stabilizer but I will be repurposing my measuring plates as the stabilizer holder instead to eliminate the stabilizer flex as a distraction.
The reason I need it mounted on the bow is because to have the bow perfectly aligned to the wall and consistent will be near impossible without massive fixturing expenses. Plus a small change on the angle of the bow moves the lasers in vastly different directions due to trigonometry changes. I will test to see if there is a change with a grip or not on and how much it changes if so. Also either way I will be doing it the same from bow to bow, it will be impossible to replicate everyone's pressure point as some use high or low grips on their bows, so as long as from bow to bow is consistent it will be okay I think. Ill ensure the draw board mechanism is aligned with the grip.I don't think there will be a difference in how many "fingers" pull the bow back as this will just draw the bow further, although yes it may flex the top and bottom slightly differently and I have a jig made for that so I will test, although 3 under vs split finger vs string walking changes this anyhow so potentially simpler is better to prevent bias and less then universal information imho.
I would recommend a fine point marker (like a precision drawing marker) instead of a pencil, as friction is not required to make a mark, just pressure. This would allow for more consistency in marking.
Good call
Yep, check Rotring pens . Also maybe use milimetered paper...
Great start but one thing. With the left movement have you allowed for deflection in the jig. As the frame will bow in words with the draw weight.
The measuring jig and device is 100% the bow, the draw board on the bow press is not part of it other then drawing back the bow.
I thinks those mesurement are very intersting to add to a review and completing a database with those results !
To make things more relatable I think you should do the mesurements several times so you can have the deviation on your mesurements and eliminate mesurements error from the conclusions.
Yes, all planned on several tests and several measurements to confirm consistency. This video showw 2 draw cycles with essentially identical results.
Great video. There seems to be a bit of side torsion as well. The horizontal laser seemed a bit off-line when in full draw.
Idea: Aim at 10 feet on a blank graph paper at no draw and take a picture. Next, Aim at same ‘target’ at full draw and take picture when arrow clicks pass clicker, take picture and compare. At longer distances the deflection should be higher and easier to account to very small changes between different risers.
Actually at no draw both lasers should be at same point.
Check out my new setup! ua-cam.com/video/sxMRPhRETrA/v-deo.html
very interesting, i was thinking the riser torque but not so much..
Hey Jake, really cool stuff. Wondering about grip pressure point position and its affect on riser flex? Wouldn't the fulcrum be different with a grip pressure point rather than the bow vice contact point at the grip's throat? Another suggestion is to record the temperature during each test. It may be interesting to report the final mean +/- standard deviation as well as the raw measurement data, as I am wondering if the bow flex changes as the bow is flexed multiple times. So an additional question is: is there directional measurement drift with repeated measures (flex 1 vs flex 10 vs flex 60)? If temperature and repeated measures affect deviation, the coefficient of variation may be high. If so, taking measurements at a constant temperature may be useful (although admittedly artificial as risers are flexed within a huge temp range). If there is drift with repeated measures, maybe your protocol will need some standardization, such as three initial measurements and three measurements after 60 draws? Or maybe all my suggestions are just too deep in the weeds??
I find it unlikely after repeated draws to have an affect. In my testing the riser even flexes (quite a lot actually) from unstrung to brace height. I do think that after a bow is shot a while there may be fatigue and more flex then a new riser. I will be drawing the bow 3 times to be sure and seeing if that measurement changes. As far as temperature Im sure it may change slightly but is impossible to control based on when someone shoots at a tournament the temp is what it is. However it would be neat to see if it makes a difference.
@@JakeKaminskiArchery This is very interesting. My assumptions are 1) repeated flexion causes a slight increase in internal riser temperature, which leads to an increase in flexibility. This may be totally bogus. It would depend on the metal I would think. And it may be insignificant. 2) increased flexion in the sagittal plan, if the ratio of deviation between to top and bottom limbs is constant, is benign (there would be no effect). However, I posit that torsional flexion could worsen if it were true that repeated flexion would increase the deviation. Not only would the archer be getting fatigued at 50 arrows, but the bow could be synergistically amplifying the errors. Most likely this is all crap. But fun to think about anyway.
Hi Jake, great video as usual, love this stuff. One thought I had is that may be as the long rod is lets say 5" below the riser pivot point in the fixture, any flex in the riser at full draw between the pivot point and the long rod mounting point would move target point down and the centre laser point up on the target ?
Yes agree, this is why I may use the arrow (dot laser) as the reference and note flex of the stabilizer separate from the other two measurements.
One question I would love to see you test and answer is how does tiller affect this? Is there an "optimal" tiller that equalizes riser flex for different risers?
I could try that some day.
hi, great vid. would it be worth comparing cheaper to high end risers. keep it up. thanks
Looks like the horizontal laser line is showing some sideways rotational flex, looking good. Can you 3D print a laser pointer holder that will allow for micro adjustment?
I probably could. will see what I can come up with in the future.
hi, at 32"28' there's a kind of weird thing flying down from the upper right of the screen.... Great vid by the way, didn't expect such a flex.
Nice setup and to be honest I was a bit skeptical about travel of limb pockets because the riser is so much more ridgid than the limbs. You proved that they indeed move when pulling back the bow. But I don't believe the pockets travel as much as the lasers on the paper do. I think lasers in the setup exxagerate the actual movement of the pockets. It is like hold a long stick at one end, move near this end for lets say a mm. The movement you will observe on the other end of the stick will be significant higher (propotional to the amount you moved the stick though). So imo the measured movement should not be considered to reflect the movement of the pockets 1:1.
Sorry for my poor explanation, hope you get my point.
Yes of course, due to parallax they will move less. However a TINY deviation on the line makes a massive impact difference on the target (similar to the lasers) so ANY movement in the wrong way makes an impact on results.
I wonder if the results for flex out of plane is depended on the lateral adjustment for the limbs, e.g. will limbs that require the limb adjustment to be moved to the side give different results than limbs that are tuned with limb pockets in the middle.
Anyhow I'm looking forward to seeing more tests like this, it will be interessting to see how different risers compare to each other.
I'd be really interested if you could/would compile data across the spectrum from entry-level to high end risers. That would be very educational. Stay safe, Jake: that cough is a real worry.
Id like to for sure. I plan on it as budgets allow.
Hi Jake, with the data online please can you report the deviation as you've said, but also the XY coordinates of each three points. (0,0) being your original start point. This will allow easy future data analysis
A different slant, but while they're on the rig, is seeing how much the tiller changes from rest (static tiller) to full draw (I'll call it dynamic tiller). This would seem to test the limbs rather than riser, but how they change over a draw is interesting.
Agree, I will post data similar to that in x and y deviations. Also I will work on swapping limbs back and forth to see how much change there is and try to take account of the tiller change.
As a precaution, please remove the arrow before you go placing your head in front of it at full draw.
Yes I will.
Interesting. Hope you can do the same tests on the budget oriented riser, like WNS.
It's done by Kostka Sport: ua-cam.com/video/c9uypsP0rvk/v-deo.html
I plan on it.
Pretty interesting. Just devils advocate, is it possible that some movement could be related to the bow press arm and the round shape as draw weight is increased?
na, same as a grip relatively speaking. Plus think of those with high wrist grips, I bet its essentially identical to the peg I am using.
Shorter risers you’d expect to flex less as I’d imagine them to be stiffer. Likewise carbon you’d expect to be stiffer too. Also, a useful unit of measurements would be y-deflection per pound per inch of draw length
You should talk with ThisOldTony about mounting and indicating the setup.
Love to see the axis!
Its the millennium one as well!
you're a machinist , google dial indicator alignment basics . Set a stand to fix the riser in with four dial indicators at top and bottom of riser...instant measurements! The laser is fun for showing effects but dial indicators, strategically placed, will give the best idicators of what's happening where. Plus the distance to the paper would seem to exaggerate the deviation at the riser...idk. Industry has been using these forever. Yes there are laser measuring tools as well, but, super expensive. Depends on what you're after I guess. I may be way off base.
Side note...with that laser on, might be interesting to see the effects of torque, both bow hand, shims, and string hand, jig the width of 3 fingers to twist the string....I know that's what holding me back....IMHO.
Thanks for all you do. Learned a lot this year.
Started doing SPTs with you. I load and release an arrow, from 10' at a # on my target face, at the end of 20 sec. Tougher the second time around, lol.
To build a jig that will not move while holding the dial indicators and will not influence the bow is pretty much out of my budget or possibility range at the moment. I figured the KISS method at the moment was a good proof of concept and a starting point with my current budget.
As a nerdy archer I love this. Not sure what to do with this data but we can at least hold manufactures accountable for the things they claim.
Hey Jake, very nice idea for measuring the riser flex. I would however suggest different measurement method. More complicated, but in my opinion far more accurate and precise. Consider measurement jig consisting of a stiff rod or beam attached in the middle to the raiser (using either plunger button holes or some sort of vise like clamp) , parallel to its vertical axis, so the beam ends are next to the riser limb pockets. The beam should have a holders at each end for the dial indicators, so the deflection in the vertical axis can be measured. For measuring the out of plane flex, the said jig could have perpendicular extensions at both end with another set of holders, and the measured riser should have peg attached at the limb pockets, in similar fashion like your top and bottom laser holders, but I think they might need to be longer, perhaps a 10 cm or longer. Those pegs would serve as reference points for the dial indicators attached to the perpendicular beam extensions. Then, the off plane deflection could be measured by measuring the distance of pegs to the beam perpendicular extension. This way you could measure the deflection few orders of magnitude more accurately.
I'm not sure if I described my idea clearly enough, if not, please let me know, I could make some drawing for you.
I agree 100% However to develop this fixture would be more costly then what I have on hand currently. Plus storing the thing and making sure it does clamp the bow without affecting the flex is the problem. This is why having it free floating in space as we do when shooting was the choice.
I agree on the accuracy potentials but this is why I will draw the bow 3 times minimum and measure each deviation 3 times each to have averages to hopefully take out error.
@@JakeKaminskiArchery Yep this is more complicated, so there's always a trade-off. What you might want to consider with your method, is to measure the flex only with reference to the middle laser dot. I don't really see any advantage of having that screen mounted to the stabiliser rod. If you have enough space, you could cast the laser dots on the wall couple of meters away - this would decrease error introduced by hand drawing the dots. You could also use camera to do photographs and do measurement by pixel counting, you would probably need to manually set the exposure so the sensor won't get saturated, and have the camera inline with the arrow line to avoid introducing parallax error. And if you're really patient, I would suggest taking more measurements, to see how much noise is introduced by the measurement itself.
Generally my point is, if you like to do real data driven tests you might want to make sure that you get your methodology right. This I think will be important when we get to the point when someone would want to compare the different risers, not necessarily to say which manufacturer does the better job, but to see for example if composite riser behaves better than aluminium one, of if its really worth to pay extra for riser made out of 7075 alloy than your regular 6061.
Anyway, this is awesome project. Thanks for doing this. I would be really happy to also see some limbs comparisons, like draw force curves and speed/pound measurements. Great work!
Having the paper mounted to the stabilizer is important because if not, all 3 lasers would need to be perfectly level and square to the riser itself, AND the riser would need to be perfectly square and level to the wall, this is impossible to do, and can easily result in error. with 3 different lasers, you cannot have. them level and pointing at the same spot on the wall... if you saw when I first started to draw the bow back, the bow rocks and moves. This causes a distortion on the wall where the dots are, and will not be at all measurable due to the change. Isolating the measurement ON the bow essentially removes that issue. Yes the stabilizer moves down as I draw the bow, so its just another reference point to be measured compared to the arrow (the dot).
Same thing when using the camera, the angle, distance, framing etc would have to be 100% perfect every time to compare apples to apples. Being able to remove the surface from the bow to measure without disturbance is important imho. as bumping the lasers and interrupting the beam happens and is difficult to measure without the drawn dot. Ill use millimeter paper in addition to what I use now in the future and that will help a lot with consistency however I expect percentage points of difference between bows (usually) not millimeters.
I appreciate the feedback for sure and will further my explanation and methodology as to why I am using the paper on the stabilizer as a reference at all. I thought I had it all figured out on 2 other videos that I was filming to show this exact thing and saw a major flaw (ie using the wall) and had to stop the recording and went back to the drawing board.
@@JakeKaminskiArchery Thanks for the explanation. One more idea when it comes to the camera - you could actually mount it to the stabilizer rod itself, you said you have the 3d printer, so making a holder that would allow you for repeatable measurements shouldn't be too difficult, that in my opinion might be more accurate and convenient than pen and caliper or millimeter paper.
Hey Jake, really interesting video. I was wondering if it might be more accurate to have your drawn crosshair independent of the bow and positioned in line with the nock point on the string and where the riser contacts the draw board? That way you remove errors due to the end of the stabiliser moving as the riser flexes.
I will use the "arrow" laser as the ultimate reference for sure... Thanks for the suggestion
26:31 Afterlife archery channel.... "Hi mine name was Jake Kaminski and I was two time Olympic silver medalist before I was pinned to the drywall in a freak accident..."
Seriously, though, I'd be interested to see the results of many of the same riser, that is to measure the consistency of the flex within a production run. Similarly, it'd be interesting to see the relative flex of the risers of previous world champions. And, being somewhat of a gorilla, how much flex is in a 27" riser compared with a 25" riser.
Good video, thanks.
dude its crazy how much it flexes
Insane when I was pulling it back for sure.
Hi, do you get the same deviations at different centre shot and tiller settings? You might be able to eliminate the horizontal deviations and even up the vertical ones, hopefully getting a better tuned bow and better riser to riser comparison. You could record amount of adjustment needed and compare consistency from limb to limb
The horizontal deviations shouldn't change with center shot based on my reasoning however limb alignment would for sure.
Very interesting
Do you think gillo gt riser will flex more at 32 inch draw.
I got a samick riser and I know it twists alot at 32 in
draw.
Cheers West oz
Im sure it will continue to flex more with more draw weight and more draw length. but all bows will.
I can understand why you don't want to do riser v riser comparisons, but I'm interested in how a carbon would compare to an aluminum riser, deflection wise...
No worries, you can check the data and cross reference once I have the database up on my website. I have flex tested the ATF from W&W and plan to flex test the TFT next (possibly today)
it would be nice to test if there is a difference between 25" and 27" riser.
Im sure there is a difference and more then likely a reduction in flex of the 25" risers.
@@JakeKaminskiArchery this makes even more undecided about 25" vs 27" XD
would also be interesting to see a difference between different aluminum types...though there aren't many risers that come built in more than one kind of alloy. actually the only one that comes to mind is the Kinetic Sovren, if memory serves me well
So based on maths, do short rizers flex less? and what does that do to strength of the rizer over long periods of time? (for example if you ve been shooting with a bow for like 10 years)
Do you plan on doing any compound bows also?
I could. I don't have the resources to fund compounds but yeah that would be fun.
probably should flip the limbs around too for extra data...maybe one limb is pulling 46 and one is pulling 44. Since they're sold and measured as a set you never know if one is stiffer than the other. And a stiffer top limb might flex the riser differently than if it were a bottom limb. I guess that's irrelevant as long as you always use the same limbs in the same position for every riser. Just thinking out loud.
I will be sure to try something like that, good idea.
Are you actually measuring the true deflection of the riser pockets in x and y axises, in millimeters or the effect of parallax from angle deflection at laser mounts under load?
I'd have to calculate that someday for sure. This measurement is of course with the parallax
Instead of using the stabiliser to mount your plate , make a mount that bolts to the rest/plunger holes like your first concept but that is the same length as the stabiliser. That way the plate and laser are mounted from the same point, which should negate any flex difference between the stabiliser mount and the rest/plunger mounts.
I can just use the arrow point as the reference and add the stabilizer flex as an extra data point reference. At least this is my plan at this point
So how did the testing come out?
Also, should take tiller into consideration. E.g., how separate limb weight affects on those measurements
Indeed.
I get the impression you're in your element, in the detail, in the engineering : ) Pioneers have to put themselves out there, it's good to see a new approach and data. As with barebow, enjoyed watching you discover a new archery journey... but don't forget the barebow ; )
Super exciting for sure! I will not forget barebow that's for sure.
A dial indicator top and bottom will give good measurements too.
but where do you mount them? Thats the question.
@@JakeKaminskiArchery one long bar with an indicator at each end. Put one short bar near the middle, perpto the long bar. The short bar will be used to mount the assembly on the sight window or the stabilizer insert
I can sketch something up if you don't understand
You kind of had your head in front of the arrow about 25:35. Looked dangerous, Jake.
Agreed Will not do again.
I wonder if the results are affected on where the grip your setup applies pressure; i.e. whether you should have the horizontal bar at the same place as your hand would apply pressure at full draw.
In fact, to take it a step further, aren't you in fact modelling a shot where the archer applies pressure to bow's throat and uses a release aid?
So, wouldn"t you need to somehow model the way of gripping the handle and pulling the string as is common for the bow's target culture?
F.ex. thumb draw, three fingers below nock, and two fingers below nock might affect how the bending behaves, and the bow might have been designed for a specific kind of draw and archery.
I mean, if you think of the test setup as a person shooting the arrow, you might reach a more accurate and rich physical model. :)
@@vilidious Why does any of that matter? Jake is testing the flexing properties of risers under typical shooting load. All of those variables are irrelivant unless you are actually shooting an arrow and measuring that for some reason.
@@mrnice752 Doesn't the behavior of flexing change depending on what the "focal point" of it is?
Especially since I assume the form and material of riser and limbs are not uniform.
So I'm guestimating that the vertical spreading behavior of the laser dots would change depending on what is the center of the bend.
Of course, if you want to just compare roughly how different risers bend, it might not be a significant issue... it might not be so even if you adjust the way it is bent either, but if the experiment is done in order to gain information on how the bow behaves when it is shot... then isn't that what should be simulated/modelled?
I'm not sure how thorough bow manufacturers are with their design, but at least in the ideal world I believe tools are tailored for a specific purpose and way of use... which is why we also have different kinds of bows.
So yeah, that's my motivation with that comment... to note the existense of forest from the trees.
Whether readers feel it's relevant or not, is their educated decision... but at least they can make that decision.
I'll try testing things such as this with "fingers" that I have to draw the bow back and make a hand to hold the grip in similar ways to see if differences are seen.
@@vilidious In theory, yes., moving the resistance point on the grip should effect the results. If you knew the exact forces and coefficients you could calculate that difference.
In reality we are talking fractions of a mm, measured by eye with pen on paper, I very much doubt a couple of inches difference on pressure point would make a measurable difference to the experiment.
I hope you are doing this with even tiller?
Good call.... will need to retest. I knew I forgot something! Thanks for the comment!
@@JakeKaminskiArchery No problem, you went into such detail I thought any minute now he will mention it.. Easy to overlook the basics if focusing on the minutiae. Keep up the great content! Cheers
Was about to ask that tiller question too. Thank s
Also would you build a small part to mimic the hold of the string with 3 fingers, giving the string 2 different angles???
How much speed do you think riser flex gives to the arrow?
Id say it takes away from the speed imho.
The Harbor Freight calipers are really good quality. However, like any electronic calipers, they have a rather high parasitic draw on the battery when turned off. The trick is to just remove the battery, after each time you are done using them. I have had batteries last well over a year, with daily use. I have been a machinist, for the oil industry, for the last 9 years, and use a pair of Brown & Sharp dial calipers at work, so I do not have to worry about batteries dying on me in the middle of a job. I have tested many brands and the Harbor Freight brand has always tested equal to my more expensive brands, in terms of accuracy and repeatability.
Great idea!
@@JakeKaminskiArchery If you are wanting, I have an old Hoyt Gold Medalist magnesium riser, dated from the mid 90’s in 95+% condition, that you could test. As long as you can guarantee no damage will come to it. It was my first true bow given to me, by my parents, when I shot indoor competition. Would be interesting to see the difference from then to now. Maybe even a shooting test, to compare how ergonomics, shoot ability, weight, forgiveness, and shot feedback has changed throughout the years.
Time will tell on that one. I will be checking to make sure I can do this test without damaging the finish of risers first from the tape and the peg holding the grip area. Id hate to damage your bow.
@@JakeKaminskiArchery Ok, offer will always be on the the table, if you ever change your mind.
wow I'm amazed
Same.
Can you make a video about target panic?
I would think most of the movement is at the grip position
PS PLEASE test the NANO TFT and Nano tftG
www.amazon.com/Orion-7033-Precision-Slow-Motion-Adapter/dp/B0000XMV86
I think this is the type of mount for your lasers that you're looking for. It has fine and course adjustment for pitch and yaw (panning). You'd just need the diode block to mount to it.
Cheers
show for the atfx please!!! :D
Soon!
@@JakeKaminskiArchery thank you! cuz i just bought that riser hehe :)
WOW
Caliper, not micrometer. Also, its important for your viewers to understand that the flex deviation is much less than the measured value you state, because the measured riser flex is magnified significantly by the distance between the laser and the laser target. Honestly, I wonder if this is a solution looking for a problem. Insignificant riser flex, as shown here, is an infinitesimal consideration relative to other much more variable elements of the shot and equipment (like limb twist). The reality is that since any teeny weenie flex is consistent from shot to shot, there is no accuracy difference between one straight riser and another, though they may feel differently. I appreciate wanting to quantify, but I wonder if a set of more subjective “feel criteria” may actually provide more value to the viewer as to how a riser might shoot for them.
I hear you, and mentioned the parallax issue in the decription.
However, a small tiny bit of error on the human side makes massive impact points on the target at distance, again due to the magnification of that effect. IIRC I did the math once on the room for error on the bow hand side (if the nock stayed motionless) the point of the arrow only has 1/4" total margin for error to HIT the entire 122cm target at 70m. The ten ring was something like the ball in a fine fall point pen.
So yes, in my opinion the movement/flex/twist is relatively infinitesimal (relatively speaking) to the archer, but down on the target I believe it is important.
Also I do always give feel feedback criteria in my reviews, you may not have seen them so no big deal on that one. I have been searching for a way to prove and measure actual data and not just anecdotal evidence of what is better or not. This will also take out my and anyone's bias in reporting how something "feels" and prove if bows are getting better or worse.
Now as far as the actual verbiage used, excuse me if that is distracting to you as a viewer but I believe you understood the gist of what I was explaining. I know they are calipers and use them all the time at my other job forgive my brevity and misuse of terminology.
@@JakeKaminskiArchery Huh. I have always believed otherwise about risers; that they are largely insignificant other than looks and feel. Ill keep an open mind and am interested to learn what you discover. Love the channel and thanks for all the great content!
Cheers.
Quick math shows me .286 degrees of flex on just the top pocket alone, which if you spread that out over 70 meters you are looking at around a 34cm deviation. Now this doesn't take the bottom pocket into consideration of course nor limb twist. Again I believe that both the riser flexing and limbs twisting will be consistent and arguably moot but what if they make the likelihood of mistakes inconsistent or biased towards one direction? I sure wouldn't shoot twisted limbs in the Olympics if I had the choice, so I believe the same about risers too. Equal flex no matter how much and in plane is what I would choose. We will see if that exists and potentially is better or worse with different manufactures.
This flex is consistant. With every shot....
Agree, but what if it is uneven and can cause larger deviations of arrow impacts when making mistakes? This is why I am interested in more discovery.
@@JakeKaminskiArchery uneven should still equate to constant. Unless the poundage varies on each pull. I dont see a slight devation in release causing significant devations in limb alignment.
The other thing to consider is riser clearance with string walking. Risers with less window clearance will torque less for any given material thickness. Which in certain crawls can cause erratic clearance.
It kinda depends on what you class as consistancy. I think for barebow a little more window clearance is better than 0.05of a deg of rotation.
Your measurements look significant. But they are at a distance. Double the distance double the measurement. Something to note opposed to making the industry look like they make jello for risers.
Your techneque for measuring this is impressive though. The use of the X vs + to distinguish upper from lower is a stroke of genius.
@sid I mentioned this in the description about the parallax to not freak people out. I forgot to mention it in the video and to go out and re shoot a segment to add it in was not in the cards. Still not feeling well so I just wrote in the caution to people.
@@JakeKaminskiArchery my bad. I didnt read the coment... good to see ideas being tested.
My only fear is people hang too much on one attribute. When there are many design cross roads to choose when designing a riser.
I hear you there, however basically all the other design cross roads are anecdotal and very difficult to prove. This is finally some hard data so it should be taken with some seriousness. I suppose as much as how much the riser weighs.
I think you're over thinking this stuff.