Outstanding explanation of flex tuning vs. nock tuning! The breakdown was clear and comprehensive, making the complexities of both methods easy to grasp. This video is a must-watch for archers looking to fine-tune their equipment. Thanks for shedding light on these essential tuning techniques! 🏹🎯

This great for people to see. Also people who can’t get 2 sided broad heads to fly don’t realize they need to line them up with the spine index of the arrow. Your method makes that quite easy without using a ram machine. Also I think it would have help people see you shoot the same arrows you spine indexed with the nock misaligned to show how truly the effects the paper tear.

This is the perfect way , any length of arrow. 14 years it's never failed me . Great video.

I did this and it works!!! Thank you for some great advice! It is a no brainer, way better than nock tuning.

Brother, You made nock tuning idiot proof!! Thanks for a very well made video... Craig

Excellent presentation all around!! You are an excellent teacher, even down to the cadence of your speech. This is a really well done video in all aspects. Thank you, blessing to you and yours!

So I got my 36" long section of 3/4" NPT pipe delivered today and got the set of clamps for $9 from Harbor Freight. I had eight Axis shafts marked in 15 minutes. Thank you for your videos! Saved me so much time from how I nock tuned previous builds.

I have that same pipe clamp and i just did this!!! THANK YOU!!! I subbed. If someone reading this is skeptical, just try it and when see just how LITTLE you have to rotate the arrow to get it to either side... It is truly eye opening!! I just haveto replace a D loop and back to the paper!! Thanks again!!!

Between this video and John Stallone’s that you mentioned I am blown away by this simple concept. I would like to point something out though. My thought is that this works better on .003 shafts than straighter .001 or better is not because it’s flexing with spine as much as it’s flexing in the direction of the defect in straightness. Maybe both factors play a significant role in deflection. I don’t know, just food for thought. Regardless of the “why”, I’m super excited to get my next 2 dozen shafts behaving similarly and with less headache. Thanks a ton!

Sounds like a great idea and cheaper than the $300 + dollar spine finder pro tool.

Thank you for sharing this method. It’s always great to see how different people use different methods to try to get to the same place! Logically, this seems to be the most accurate way to align arrows. Nock tuning (I’ve done it) is great, but is influenced by too many other factors. If you change your release or anchor position, the nock tune becomes void. It’s the same if you start to torque the bow. If you combine this method with torque tuning to determine the proper rest distance from the riser, it should creat a very forgiving setup. Fantastic information!

It's called Puring. Any avid golfer knows the goal of spine tuning their golf shafts is to find the most stable orientation to ensure the shaft bends on a neutral axis. That little jig you built is a game changer. You ought to patent it and market it. Google SST Puring and you'll see how important it to locate the spine and orientate the shaft to the optimum orientation an bend consistently.

I use this basic method on my lathe. I made 2 buttons that the points will go into. I put a point in each end of the arrow and put it between centers and turn the tail stop in to bend the arrow. When it bends I mark the highest spot. Then I loosen the arrow and put that mark up. Then press it again. If the mark goes to the top then that arrow is done. I check each one at least twice. I have never had an arrow bend in different directions. It bends the same spot every time. Sometimes they bend down and i cant mark it so I turn it 180 and bend it again. It will bend up and I can mark the top. Can do a dozen in 5 minutes easy. I also found if I bend one a little or a lot the direction stays the same. This method works good for me. No issues or nock tuning needed.

Dude..... scientific reasoning, tested and proven results = facts in my book....... Im going to buy one of those clamp things tonight, I've spent so much time nock tuning in the past. Where have you been for the past x amount of years lol... Thanks for the video.

The explanation is that you are at the same distance for every test. Try it at different distances and you might see a different result. The window of "forgiveness" will seem much smaller when you bare shaft multiple distances at once.

Mst in Texas. This is the second video of yours that I watched. It make sense. Can't wait try it out. Thanks a lot

I used to build custom fishing rods. Finding the spine is important for proper mounting of line guides. Spining is important because if the rod is spined improperly the cast will not go where the fisherperson has aimed. When I shot archery in the 70s IIRC my mentor/pro always spined my X-7 Easton's by somehow pressing down on the middle of the shaft which was mounted on rollers. He straightened my arrows that way also. That is all I remember about that.

Cheers Mat for your generous help 🙏

Thank you for the info. I'll try it when I get bow back from the shop with my new arrows that are not fletch. I'll be following for more info.

This is the same idea as they do for golf club shafts when they pure them. They vibrate the shafts and see which way they want to flex. Then they assemble the club and align that bend point inline with the club face. I’ve been trying to figure out how do do this easily with arrow shafts. I think this is it.

Well done!

Very interesting approach.

They are different arrows but with the different weights on the front can actually make the actual spines alot closer

Okay, sorry to be against the grain here. However, I used same clamp, use a micrometer to mark dimple spots and an automatic center punch. Victory 300 spine XV’s. Ethics 225 SS milled inserts and field points, I squared each end with arrow square tool. I marked and labeled point/insert combo nock/tip not to confused them. I would get great results at first, until i turned the insert/FP 180 degrees. Then the ‘weak side’ would rotate opposite side from previous result. This test is only as accurate as your clamp,arrow specs, and components, which none of them I used were cheap junk. Try it for yourself. However, I did not have luck.

Dang Brotha, best tip I’ve tried so far. Thanks for sharing, and shaving some time off nock tuning the alternative way😎😇🙏Kudos 🏹🏹👍👍

The reason you were able to add that much weight is because you added it as insert weight. From my experience, as you add insert weight, it effectively shortens the bendinging portion of the arrow, creating a stiffer dynamic spine.

I hang bamboo arrows between 2 nails, with a 2lb weight Mark an average point where you can get most of the batch to meet (because they will always bend more on one side), cut the nock to align the stiff side to the bow. (You can rotate the shaft to get the bow side spine consistent) I don't bother with carbons, but if I was pushing beyond 50 meters on a target bow, I might try it.

Hi. It's the first time I watch your video. I've design a similar device to do the bending test like you do, but I put my device verticaly to cancel the action of gravity on the center of the shaft. I found that vertically, the results were different and more consistent than placing the device horizontally.

Great video! 👍🏻 saves alot of time. Years ago I did the soapy water method. Pretty much the idea is that the spine of the arrow will rotate downward sinking towards the bottom. I wasn’t very consistent with being able to mark it since it was all wet. Will be doing this next. 🎯

That is very interesting. Thank you , I instantly start with my new arrows.

Fascinating! Thanks for sharing - this makes a lot of sense!

This makes a ton of sense! Thank you for sharing.

Good info. Know what I’ll be trying.

Glad to see you on KZfaq I got banned from Instagram years ago lol

Just followed this method today... it all out works!

I have a question sir. Your explaination suggested to mark the index when the bend is facing downward. I just a saw a video of some guy doing the same method but he marked in when the arrow are bending upward. Which one the correct one?

I normally do the bend test, mark the weak side. Ratate the arrow numerous times without checking. Then do the test again. 98% of the time i will get exactly same side. Better to do more than two spins

Great content. Thank you for sharing

Thanks for sharing this. It's a big help.

looks like a good way to "tune" poorly matched/spined arrows, (manufacturing "matched" all carbon shafts is inherently difficult) ,, You are marking the stiff side of the shaft.. back when carbon arrows first came out you could look at the end and clearly see one side was "thicker".ie the hole/bore of the shaft was not centered, maybe you still can?? AFC s were tough to get shooting as well as aluminum without some type of matching....The "beman" was not like this, they were a 2 part shaft, it had 2 seams opposite each other. ., I think i was probably the first to win a compound target nationals with carbon arrows back in 1990 (NFAA field nationals and PAA outdoor target nationals ) The beman had a good stiff nock but the shafts were easily damaged (i went through 6 dozen shafts that yr) .& did not require anything other than paper tuning to get them to group great. Easton bought them out a yr or 2 later. Easton overcame the centering (spine) problem by using a small aluminum shaft core. I'm sure this "bend" tuning would have made the other arrow all carbon arrow shafts competitive when combined with weight matching, Wish this info was available back then!! (The entire shaft weight is what is important, not just the point)... Thanks for the video... . .... . .

Bend tested my crossbow bolts. Now I need to determine which way to have the bend go when I shoot. I think the bend direction should be away from the rail, so the flex is not pushing my bolt bend into the rail.

I had no idea buying my first traditional bow that it was going to become the most nerdy hobby that I embarked on but I'm absolutely into it ... Just sad I didn't know all this before buying my setup yesterday because I would have had a lot more input! I had the the shop set my arrows and hand me the bow and I went straight to the targets lol

Very interesting, I like easy processes of your press bending the arrow. I do similar with a spine indicator but for some reason I put the stiffest part of the spine up. So I think its opposite of your set up. Don't stock factory spine aligned arrows come with the spine mark up? Now I have to test some of my factory made spine aligned arrows and make sure what is going on there. Some day I will get a bar press like that and check it out. Thanks for the great video.

Good video! Ive been using this same process since the mid-90's when the skinny little beman and AFC carbons started getting popular, because it was too hard to "float" them the way I could with aluminum arrows. Again good video!

Great video and very informative. I do have a question about something you mentioned early in your video about the shop setting your bow up and paper tuning and then sending you on your way. As a tech I am curious what else you would have liked to have them do for you as a customer. I am always seeking to offer the best experience.

I have a similar clamp but mine has too much play in it so checking my arrows was unsuccessful. I tried it with the clamp horizontal and vertical with different results for each.

Have you done this method to find the weakest side of the arrow.... and then indexed the arrows to see if they were always opposite the "spine"?

I’ve been using this same flex testing method for years. After countless dozens of arrows, I’ve yet to find a single shaft that nock tuning impoved after the flex test.

Shooting the arrow so close to the paper will not reveal issues. You need to be able much further back

Haven't tried but read you can float arrows to find the carbon seam.I just pay the 2.50 a arrow to have them spine aligned.

I do it same way but use a bow press and it works absolutely great video thanks funny thing people don't believe me

To prove your point I think you should turn your nocks randomly and shoot with the heavy points again, I’ll bet you will get the same results. As long as your center shot is the same it doesn’t matter how much weight you have on the tip, that arrow will snake right through that hole in the paper I guarantee it

Good idea :) Will check this out.

Nice video. I would have liked to seen you take a couple of tuned arrows and turned the nocks a few degrees to see the differences when shot through paper.

I have a question in regards to the pipe clamp set-up. Does it make a difference in the way the arrow bends if the dimple in the end clamps aren't in the same location to each other? Not that one end is lower,higher, or offset to the other.

The shop didnt help you!!! Wow. They wouldnt get me money I know that. Great content, Thanks

Makes sense just from a common sense standpoint. If youve ever built a fishing rod, step one is finding the spine of your rod blank. This is done by flexing the blank so it naturally shows its weakest side while bending. Arrow construction is not much different, and similarly you are looking for the same type of bend point.

There's always one... Can this be done with aluminum, or am I missing something?

I tried the bend test with 'spine aligned' Victory RIP shafts, only about 50% of them lined with the factory spine align mark. Not sure what that says about the whole marketing concept of 'spine aligned' arrows

So I'm trying to apply this method to crossbow tuning. I started paper tuning my crossbows with fletchings on. It works pretty well but because you're limited to the three positions of the fletching, there is variability error to arrow even if they're more consistent shot to shot with the same arrow. If you bear shaft across both bowl through paper, it's always tail high. Because of the way it comes off the rails I think. So after spine matching them all, do you have any guesses as to what direction would be best when shooting out of crossbow, stiff side up or stiff side down?

To be fair, nock tuning actually shows what is happening when the arrow is fired from the bow. If this is out of square, even in the slightest, you will get a false reading. Nothing here is really precision gear.

I really wanted to get behind this, tried it out and just couldn't get consistent enough results with 3 different spine arrows. I flexed each arrow 6 or 8 times, and it flexed different ways each time. Great idea just not for me.

I'm not set up to tune my bow at home, so once I flex tune my arrows do I take them all into the shop and have them tune my bow for every arrow or just one from the group? Thank you so much! Dig the bracelet by the way!

I’de feel happier if the bar clamp was oriented vertically. This would eliminate any gravity induced “pre-bend” tendency.

Good that you’re thinking and tinkering. However, explanation is going to confuse people. Nock tuning is dynamic spine test and will not necessarily be aligned exactly as your first test which is more of a static spine test. You really need to do both with each arrow. Interesting though

?? what side is actually the weak/strong side flex in or flex out ? and does it matter what way you mark and fletch if you are consitent Thanks

When you turned the arrow, it flexed same direction each time.

Hmmm definitely going to try that method It all makes sense to me

Dynamic spine vs static spine this only finds the static… I’ve tried the bend indexing and found it pretty random… have a arrow bend down turn the arrow bends down.. theoretically it makes sense just like floating them in water but till Tim gillingham does this I won’t (not a sounding like a fan boy) but Tim takes a very logical scientific approach and tests the shit out of everything

Where did you get your bar clamp at???

Thanks for the tips. What kind of press is that again?

So you’re using compression to spine align? Makes sense

I think I love you.

How did you come to the conclusion that the bow wants to bend the arrow down at 180°? Honest question. I am a spine indexing proponent and have always wondered in which position the spine would fly best, but have never spent the time to test.

Have you nock tuned for accuracy over shooting them through paper?

Should the arrow be leveled when you put it in the clamp? Would that affect results?

Matt what was the tool on each end again that compresses the arrow and where did you get it at, thanks for any Info.

Is this effectively a poormans spine finder?

I tried this, but my arrows only bend up. Any suggestions?

Awesome idea, I'm gonna try. question So when you Fletch your arrow. Do you put your kock flitching directly on that pen mark?

So on your test the bend being straight down. Does that put the weakest part of the spine facing straight up and the stiffest part of the spine facing 90 left or right?

For compound bows, should the arrow always bend down on bottom vs bending up on top?

What bar clamp is this ?

What bar clamp was that?

I did the same thing except I used my lathe. The dozen arrows had already been nock tuned so I wound up with marks for nock tuning and bend tuning on the same set of arrows. I then shot them thru paper and the nock tuned arrows gave better results thru paper. You are right bending the arrows is much faster and I really wished it could replace nock tuning. But in the end I went with my nock tuned arrows because I was shooting fixed broadheads and they flew good.

Not bad.

I made this tool to a t, and my arrows keep bending in the same direction (360 degrees around) no matter which way I spin the shaft

all your doing is spine aligning your arrows knock tuning is the same idea just without any additional tools

Where can we purchase the press.

This is a noob question, will this work also with recurve and barebow setup? Or more likely for compound only..

There is a way that is by far more easy to solve this issue and that is to buy arrows that have a stiffer spine than you think you need for your bow. Way to many shoot arrows on the soft side and that makes it extremely more finnicky to tune everything for great arrow flights and great accuracy. The reality is that people can shoot much stiffer spines than they think is perfect when using something like a drop away rest or similar. And by shooting these stiff spines, you eliminate any need for nock tuning or bend testing the arrows as long as you buy quality arrows that are 0.003 or better and even most of the time for 0.006 arrows. I bare shaft tune my setup and by using stiffer spines, does it not matter if I crank up the poundage a bit, use heavier points and other changes. Way to many archers are hung up in the old days when a perfect spine was needed for the arrow to band free from the bow after releasing it. With most arrow rests and compound bows today, this is not needed at all. I have been shooting compound bows since 1986 and I have not been doing any nock tuning or bend testing for at least 20 years now. Also when using a Whisker Biscuit for one of my hunting bows, this is not needed to do as well. Buy at least one spine stiffer than you think you need and your life will be so extremely much better as an archer/bowhunter.

Your arrow did not bend consistently each time you turned it............ ...

he knows very little, the nock has a pionted shpe cut in the back so the noch aligns straight with the pencil like cut you should have put on you arrow. been archery instructer for years, both traditional and modern.. no aligning needed, there self aligning.... just a bit ofhot melt and yer good :-\

Can you do this if the arrows are already fletched?

Shoot further back like 10 -15 yards and see what you get.

Yea that 5 minutes to nock tune is terrible

Spine is blown way out of proportion on today’s bows.

This is NOT an accurate method of tuning arrows. Doesn’t matter. Nothing will beat actually shooting arrows , especially bare shaft and nock tuning. This is no better than floating arrows

A fan of the channel. Not a fan of the portrait video. Sorry man.

This is one of the worst methods of finding spine. Spine is tested at 28” so, you have arrows cut to 25.26 and 27”, this isn’t going to work. Also depending on how arrows are made with the carbon, you want have the same consistency from one make to the next. If the arrow isn’t perfectly place with the exact same distance on each side of the press , you get mixed results. If the threaded rod is bent and raising and lowering the arm as it’s pressed, you get different results. If arrows are not perfectly squared on both ends, you get mixed results. There’s just to many variables and to many things to go wrong and cause issues with this method. Plus the pressure you put on an arrow by pushing it together can damage the integrity of the arrow. There is absolutely no better way than to actually shoot arrows. If a guy is fatigued and loosing his form after 50-75 arrows, then he’s over bowed.