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Hector's Airgun Blog

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TRULY Taming the harmonics in spring-piston airguns

8/13/2018

19 Comments

 
Quite a few of you, my loyal and greatly esteemed readers, have written to me about why I have been "lazy" and about new work on the Walthers, some others are raring to see further work on the Stormrider. Sorry.
To say that I have been busy, is to put it mildly. With two little ones and an extended family trip (the family is the extended one, the trip was nowhere extended enough, LOL!), it has taken all of my time just to keep the company deliveries going.

BUT, let me give you a GLIMPSE of the things we've been up to. And, for that, let's divide this blog entry into two parts:
Part 1 will demonstrate once and for all that the DIANA Bullseye ZR Mounts WORK.
Part 2 will briefly show what some solid science can achieve where it counts: at the target.

​Let's get started!

Part 1.- Reducing the effects of harmonics in the scope:

To put everything in context, we need to start with an EMail requesting information about why the scopes break or loose zero.
The question came from a professional in the field of harmonics and vibrations, he analyzes issues from operator fatigue in the operation of heavy machinery, to structural elements' breakages that are (or are not) covered by insurance, so, to say that he KNOWS his stuff and that we hit it right off the bat, would be a silly and gross understatement. 
We spoke the same language, we understood things like Fourier Transformations and Differential Calculus, AND he became my hero because he has a LOT of toys.

What sort of toys?

Things like these:
Picture
And these
Picture
What you are seeing here is a dedicated system to evaluate the vibrations produced (in a three dimensional sense) by a machine.
There is a sensor that is attached to the Field Hardened PC that captures readings and these are sent to the PC that then uses a dedicated analysis software to produce a number of critical and important numbers:
​
- Natural frequency of vibration
- Fourier analysis of the extremely complex vibration patterns
- Maximum amplitude of the vibrations in each of the three axes (X, Y and Z)
- Maximum acceleration (in g's averaged over the sample period) suffered by different components in the system.

Airguns are just machines, as much as we may love them and even name them, they are just machines, and so, they can be analyzed using solid physics principles; and the software that applies to one machine can do a good job on another, as long as we know the restrictions and how to interpret the results.

This is the graph produced for an HW98 sensed at a solid mount, as in the first picture,  after the first shock wave has passed:
Picture
C1 axis is the axis that lies along the bore line.
C2 axis is the vertical axis that is perpendicular AND vertical to the boreline
C3 axis is the axis that is horizontal and perpendicular to the boreline.

Do note that the FIRST strong vibration to occur is in the C1 axis (as is logical, since from this axis all the impulse/energy for producing these vibrations gets sourced.
BUT the HIGHEST acceleration (after the shock wave, remember) comes in the C2 axis (in other words, it is a vertical jolt to the scope) and that the sensor, averaging over 100 samples a second (not nearly fast enough, we know, but we will procure a better sensor as time and monies permit), says it is 1g push.
Please do NOT get fixated on the VALUE, because we are measuring extremely fast phenomena with slow sensors. What will be important is what happens when a DIANA Bullseye mount is used, as in the second picture above:
Picture
Axes are the same, but take a closer look at the magnitude of the accelerations detected.
The vertical jolt to the scope is reduced to 0.021 g's, and that from the previous case of 1.00 g; that is 47.6 times smaller! Almost 50 times!

To put it in another way that should be understandable to all airgunners:
Using a DIANA Bullseye ZR mount reduces the vibrations FELT BY THE SCOPE, by 98%, or reduces it to 2% of the full recoil of the rifle.

If you have any doubt as to what vibrations can cause in things, just search YouTube for "Tacoma Narrows Bridge" and you will see what I mean.

A scope erector is not too unlike a suspension bridge. It is a structure that is suspended on a spring, whether it is a bridge or a tube suspended by cables, a coil, or a leaf spring, matters little, it just changes where in the frequency spectrum things start to go "wacky", but it does not change the basic phenomenon.
Part 2.- Reducing the Harmonics at the muzzle of an LGU:

​Now, we had NEVER had so much information, and my friend's help in interpreting the software's results has been invaluable.

My brain, being what it  is (sort of a maze of possibilities), immediately started to go in the sense of detecting which characteristics of a powerplant made the best and highest improvement in the reduction of harmonics, but my friend asked a very valid question:

¿Have you seen the oscillation reducers that are used in buildings?

Well, yes, enormous pendula (pendulums?) suspended from the top of buildings that help reduce the oscillations created by wind, or earthquakes, and in at least one case, tides.
Further research also showed that there are now machine tools utilizing some of these principles, and so the idea was born to make a device that could actually and TRULY reduce the muzzle vibrations of an airgun.

In the past, we had concentrated on TUNING the exit of the pellet to the point of maximum excursion of the muzzle's vibrations, at that point, the muzzle has reached the limit of the oscillation and is starting to return, so, therefore, at that point, the transverse velocity of the muzzle is zero, or very, very, low.
We have talked about controlling the harmonics in another entry. But now, we had the information and the means of actually REDUCING the harmonics where it matters.
​
And so, we decided to start with the requested LGU. Not only was this the rifle that my friend wanted, it was also a rifle that was known to produce very high levels of C2 axis vibration and shock OoB.
As they are issued, the rifles "jump" upwards. A simple result of the different axes on which the action and buttstock have been located.
They are easy to tune and the jump is greatly diminished by the use of a tight top-hat because then the rebound of the piston slows down the vertical jump. It becomes sort of a push-pull toy. You can read more about what can be done to the LGU here.

The rifle was procured from the Netherlands, and after a couple of hundred rounds had been shot as a "run-in", a benchmark target was shot at 35 yards to have an idea of which pellets were the preferred ones by the barrel.
Picture
These are 10 shot groups, but as you can see, apart from the groups shot using the JSB 8.44/4.53's no other pellet shoots reasonably well.

So the quest was on for a device that would suspend a weight, but still offer some resistance to the movement of the muzzle up to the maximum deflections we had found through the vibrational analysis.
We started with complex arrangements, but in the end, we settled for the simplest design that would do the job.

Here we are starting the machining of the element.
Picture
I cannot publicly publish the dimensions, or weight, or materials, that go into the finished product, but perhaps a similar test target, shot under similar circumstances to the one posted above will give you an idea of what was achieved:
Picture
You can see now that the gun shoots quite well not only the original JSB 8.44/4.53 pellets, but ALSO the Baracuda FT.

The Baracuda FT is, so far, an experimental pellet produced by H&N using a similar die to the Baracuda Match, but using a different base punch that yields a total weight of 9.57 grs.
That one rifle CAN shoot accurately pellets that differ so much in weight (more than 13%), is a HUGE result. It means that the harmonics reducer is TRULY doing its job,

Hopefully, H&N will progress from "on test" to "in production" soon, as it is indeed a good pellet (it could be better, but we're in talks about that) and it adds another option to those that enjoy accurate airguns.
As to what happened with the LGU? well it got shipped recently:
Picture
​In store for the future is, of course, analyzing some scopes to find what is their NVF (Natural Vibration Frequency), analyzing other airguns, as well as coming up with a design for a Harmonics reducer that can be fitted to other rifles. There is much to be done and very little time. There is now more and better tools that give us information to confirm, or refute, our theories.
Come, stay tuned, the best is yet to come!

Thanks to those that wrote to me, thanks for the good wishes, and above all, thanks for reading this humble Blog.

Keep well and shoot straight!





​HM
19 Comments
dan house
8/14/2018 15:43:26

wow! Hard science well described and documented!

jsut so I think I get it:
C2 axis is the vertical axis that is perpendicular AND vertical to the boreline-- so if we assigned a "degree" to it, the line would 0 thru 180

C3 axis is the axis that is horizontal and perpendicular to the boreline-- this would be 90 thru 270 ??

YOu guys should crowdsource the better sensors. If that ths the data you got from a "slow" sensor, then I cant wait the see the data from the faster set.

another awesome post!

Good luck in Poland!!

Reply
Hector Medina
8/14/2018 15:53:58

Hello Dan!

It would be the line 0-180° ONLY it you are looking at the bore straight-on, either from the back or the front, but straight on. In other words, the bore axis becomes a point.

Same as for the C3 axis. Your degree designations only work if you are looking at the bore straight on, as if you were "the pellet looking at the end of the tunnel".

We already have a slightly faster sensor (two orders of magnitude faster), and we'll see what we can get out of it.
But do remember that this takes a LOT of time from my friend;s busy schedule, AND he is an airgunner as well, so we need to allow him time to shoot for his own pleasure LOL!

Thanks for your kind words, as usual.

Thanks also for your good wishes.

Keep well and shoot straight!




HM

Reply
John Harris
8/15/2018 06:52:12

Have you considered a gyroscopic stabilizer? Similar to a Seakeeper for boats?

Reply
Hector Medina
8/15/2018 11:36:03

Dear Mr. Harris;

I hope you are not the great John Harris from the UK. If you are I am humbled that you have taken notice of my notes. If you are not, you are still pretty good at detecting possibilities, thank you for reading!

Years ago, I tested a gyroscopic stabilizer by Kenyon on a friend's rifle, a 20 f-lbs USFT. Great rifle, if only not quite rifle-looking to my humble tastes.

It was not designed to stabilize harmonics oscillations of the barrel, but the shooter's small movements (like pulse or twitches).
Does it succeed in that task? yes, to a point.

Would it work in stabilizing the barrel's harmonics? Not in my honest opinion. Why? because of the different spans of times things are happening. Gyros to stabilize pulse (as is normal for cameras and binocs) are made to stabilize movements that take seconds.
Harmonics in rifle barrels happen in about 2-4 milliseconds. So there is a 2-3 orders of magnitude difference between things.

Odds are that the harmonics in the rifle barrel would induce high velocity vibrations in the gyro, and if those hit the NFV, then you have a hand grenade because those gyros spin REAL fast.

While 20 kRPM's ARE a lot when discussing the effects of a disintegrating spinwheel, consider that we found, in our Fourier Analysis, appreciable peaks of "g" at 6.5, 13, 20, 27.8, 32.4, 38.9 and 45.3 kCPM (from 3.6 g's to 0.5 g's)

In a rotating wheel, something that happens at about the same kCPM as the kRPM's is, potentially, a constructive phenomon, again, look at the Tacoma Narrows Bridge footage to see what happens with constructive oscillations. What would worry me most is that there is a 0.5 peak at 38.9 kCPM; that is too darn close to a multiple of the base 20 kRPM's of the flywheel.

The added problem is that gyros, currently are NOT built to withstand recoil. PCP's are worthy in the sense that they do not provide enough axial energy to get the gyros to hit the stops and protect itself, but a single shot with a D48 made the original, tested gyro shut down.

Kenyon labs is working on a gun mounted gyro made to take the recoil, but I do not see a REAL application of the gyroscopic effect in spring-piston airguns.

My main reason is practical:
People/I love the simplicity of the self-powered springer.
If you add battery packs and control circuits, and chargers and all that, it's just the same, if not more complicated, than getting a compressor, a tank and all the hoses, valves and connectors that go with it.

Thanks for an excellent question, keep well and shoot straight!





HM

Reply
Hector Medina
8/15/2018 11:40:37

To all my friends that have expressed interest in the subsequent parts of this article I have to inform that several manufacturers (optics and guns), have expressed serious interest in these proceedings.

IF those talks come to fruition, then all the subsequent work MAY NOT be publishable.

I am not saying that I will not publish more about this, I am just saying that I cannot guarantee that I will.

Hoping for your understanding, I wish you all well and straight shooting!






HM

Reply
RidgeRunner
8/22/2018 12:07:26

Hector,

LOL! Of course they are! Just do not give Crosman an exclusive contract. They will end up muddling it like they did Lloyd Sikes' electronic valve system. They cannot even get a sproinger trigger right.

Being a sproinger fan I was really hoping to see what you had developed. Now I will just have to wait and figure out how to adapt it to mine.

Reply
RidgeRunner
8/27/2018 04:03:26

Congratulations on the WFTC!

Reply
Hector Medina
8/27/2018 04:55:06

THANK YOU RR!

As usual, I should have been better prepared. Too many things on my plate. As per the rules, only the three top scores for each day count, so my scores were not counted, my only consolation is that the outcome wold have been the same with the new or the old count.
So, in all honesty, the kudos are due to Ray, Matt and Cameron, who shot very well, as well as the course and the conditions allowed.

Still, it has been a trip.
When I started shooting Springer in the US back in 2010, everyone thought I was crazy. Ray was shooting PCP, Matt B. was shooting PCP. Matt Sawyer was shooting PCP. Cameron was shooting PCP up until a few months ago; but he is a phenomenal shooter, he will shoot anything well.

Slowly, more and more people are realizing the enormous challenge of shooting well a springer over extended periods of time, and that draws a particular kind of shooter.
Out of the 4 top scores in the USA spring-Piston team, 2 were achieved with DIANA 54 based platforms, one TX and one HW97.
Scopes? there were 1 March and three Sightrons
The only Whiscombe in the Team, tanked, as did another HW97 (we need to test if it is the scope, or the rifle, but I would suspect the rifle first because it started making "aspirating sounds" when cocking.

There is SO MUCH that goes into one of these things, on all sides.

Sometimes, the best part of it is when it is over.

;-)

Thanks for your kind words!, I will surely relay them to the rest of the Team, even the guy with the Whiscombe, LOL!

Keep well and shoot straight!

Reply
Matt B.
9/10/2018 09:40:14

Interesting read, Hector. 'Just a correction on your previous comment: I've actually never shot a PCP. I started in the WFTF piston class in 2009 with a Gamo CFX, and I've stayed ever since!

Hector Medina
9/10/2018 13:14:47

I stand corrected, Matt!

I thought I remembered seeing you shoot PCP at one of Ray's shoots, but clearly I was remembering incorrectly.

Apologies and thanks for reading!



HM

Reply
Clicky
2/4/2019 20:45:18

Very interesting work, I just heard of your blog via RidgeRunner over on B.B.'s blog. I just want to know what software are you using to record the signal? And what if any hardware interface in between the accellerometer and the computer. I'm looking at what Digikey has for 3-axis analog sensors, as I want to be able to know what's happening on my own air guns. Thanks!

Reply
Hector Medina
2/5/2019 12:22:26

Dear Clicky;

Thanks for your kid words!

We use CTC sensors, and as far as I know we do not use any interfase between computer and sensor. Computer is a dedicated vibrations analysis unit used in heavy industries.
I cannot tell you what software we use, I know it is proprietary to the computer though.

Sorry that I cannot answer in more depth, but the instrumentation and tests are done by a friend who is also an airgunner in his free time, but his work is vibrations analysis and diagnostics.

Good luck with Digi-key and keep us posted of what you find.






HM

Reply
Clicky
2/5/2019 12:56:21

Ok, thanks for letting me know. I had gotten the impression that you had decided to buy your own harmonics analysis rig based on these results

Perhaps your friend might have answers, could he post here?

From the 1st screenshot you posted, it looks like you were not seeing anything more than 8 G's? So if my air gun is somewhat the same as this one you were testing, maybe I should be looking at sensors that go up to 10 G's?

How many millivolts per G for the sensor you have here?

And maybe I missed this detail but what direction is channel 1 negative corresponding to in this test? Would that be the sensor is moving towards the target?

Wouldn't the bias in channel 3 be the result of which hand you fire the gun with? For example, switching from a right-handed shooter to a left-handed, the +/- bias will reverse? If so, would you spend some time tuning your hold in order to get that into balance?

I see there's just a tiny bit of drift in the calibration from before the shot cycle to afterwards. Would that be normal for a brand new sensor?

Hector Medina
2/6/2019 15:32:38

Clicky;
I have relayed your message to my friend Gerardo. But he is a very busy person, he gets called to all parts of the world to do, precisely, vibrational analyses of machines.
CCA does not have the resources to buy a dedicated software, or PC to do this (several tens of thousands of $), we have to rely on an exchange of information and some "training" on what to expect, for tests and results, all in good faith.

It's by building a community how airgunning can progress. There are not enough technological drivers (like Formula 1, or NASCAR), nor money to support them, to get things done otherwise.

About the 8 g's, I always thought it was a simple saturation and self-protection of the sensor, so I helped my friend buy another sensor and preliminary tests show that I was right. But if the $150 sensor we bought is still saturating, it means we will need to invest about $2,000 for a sensor that will not. Again, it is basically just experience talking here.
The sensors we use are 10 mV/g.
C1 is the bore axis
C2 is the vertical plane (scope plane)
C3 is the horizontal plane (Cocking lever plane in side-cockers)
Yes, we all know that spring-piston airguns recoil FORWARD. So, if the positive direction is the rear recoil (first part of the shot cycle where the piston's inertia is forcing the gun into the shooter's shoulder), then the negative sense is the acceleration towards the muzzle due to the piston arriving, then rebounding, and then hitting the end of the compression chamber on an empty chamber because the pellet has already left the bore. That is why you have BOTH directions.
We were using a bench/vise as depicted in the pictures, so I do not think it was "shooter handedness" what you see, I would attribute it mostly to spring winding direction.
My Assumption is that what you call calibration drift is really the result of saturation hysteresis, but let's wait and see what Gerardo has to say.

Sorry I cannot be of more assistance.


HM

Reply
Clicky
2/7/2019 13:07:14

Sorry if I ask dumb questions, I just prefer to see things in person before they really sink in

Now that you've brought it up, I see in the channel traces that there's a few spikes that were chopped flat, right about where everything else seems to be running short. If I knew which chip is inside that sensor, I bet the datasheet will show it's working range is around 8 G's

All the sensors on digikey that I have looked at so far, all seem to have built-in signal smoothing. This is hard-coded inside the sensor chip itself

So I guess I need to be a bit mindful of knowing the difference of a chips survivable g rating and it's working range. I was looking at an ADXL1003 & for only $53 I can get a 3-axis sensor that can handle 10,000 g's! When I read the datasheet, I found that it's measurement range is +-200 g. Sounds very useful, but I'm still not sure how well this chip can detect very fast transitions, or if it's able to see what's happening without too much noise. I'm only just now learning how these chips work

I would like to know what sensor chip you're using now, and I'm sure everyone wants to see more screenshots of whatever you use it for next

That bias being due to spring winding? Well I guess if I had really comprehended that your testing in a vise, I could've had a chance not to make such a fast first assumption! Which reminds me, I've been wondering about the value of pairing opposing directions of twist between the mainspring and the rifling

And, today I woke up with a very odd thought: A barrel is in a sense, only one half of a broken tuning fork. What would happen if it was a real tuning fork? Like as in, mount a rigid rail below the barrel, attached at the very rear of the barrel & also free-floated. Would that keep barrel movements in a more vertical domain? Would that restrict barrel motion to a more narrow frequency range? The frequency would be as easy to change as normal harmonic tuning, but it might require paired weights like calibrated tuning forks I've seen before. I would also test out a damping foam block between the fork legs. Not so much that the fork doesn't have enough control, but enough that the motions are damped as much as possible. Having my own accellerometer is going to be very interesting

Reply
Hector Medina
2/7/2019 16:09:01

Clicky;

I am going WAY OVER my pay rate here, so, please bear with me if I am not making any sense.

Our new sensor is the CTC AC131, you can read the specs here:
https://www.ctconline.com/fileup/PrdDS2013/1_VS_AC131_DS.pdf

Now, I still think that it falls short, but my friend Gerardo thinks I am exaggerating stuff, and he is the specialist, so we're following his knowledge.

Do note that sensors "self-protect" by saturation, they also have smoothing algorithms because if they didn't, then the Fourier analysis would be all haywire, so, the fact that something can WITHSTAND 10,000 g's is NO GUARANTEE that it will accurately measure 1,000 g's. It may measure accurately a little above the stated measurement range (that is normal CYA in all metrology dealings), but I really do not know which "chip" is where. Perhaps you can find out with the Manufacturer model #.

Spec sheet says that our new sensor's dynamic range is +/- 500 g's, so it is at least twice a wider range than the ADXL1003 you mention.
Spec sheet also says that the frequency response is up to 900,000 CPM's at +-/ 3 dB (or 15 kHz), which SHOULD translate into the possibility of detecting transitions in the region of 0.03 msec, or 30 µs.Take your pick.

Since the shot cycle of spring piston airguns takes between 8 and 20 msecs, we should be OK in the vibrations analysis sense.
Where I am not so confident is in the max g's of the whole system.
Remember that extremely high g's come either from very large forces acting in human-related times, OR with small forces that act during minuscule slivers of time and therefore imply a huge g number.
The spectral noise is in the µg's range, so I am not worried in the least.

We have not published any data obtained with the new sensor, because we are not ready. Things are substantially more complicated than expected.

Since the picture clearly showed the testing setup, I thought it should have been clear, my apologies for not being completely specific.

IMHE, the rifling sense has so little influence in the vibrations (unless it is very shoddily done, and then there are remedies), that it would be more sensible to use two counterwound springs than trying to mate the spring winding direction to the rifling direction. Two counterwound springs with an intermediate "Top Hat" solves some of the problems, but at a large cost (think that at industrial level, the OEM springs cost in the region of $2-5.00, compare that to aftermarket springs).

In a way you are right that a barrel is only one half of a fork, where I am not so sure is if we can make one dampening effect, deaden the other branch vibrations (like resonating but in a negative way).
It is an interesting idea and I would hope that you will keep us posted of whatever you find.

Keep well and shoot straight!





HM

Clicky
2/7/2019 22:33:29

Thanks, the AC131 was chosen by Geraldo for reasons he ought to understand better than I do. But, the datasheet is more like a summary for purchasing agents, so I wouldn't be able to really say for sure what the capabilities are with only that. Particularly with a condition like as you described, the possibility that you are dealing with very short duration impulse forces of extreme g's

I will just have to be patient & see what happens here. For my own purposes, I might just try a lower cost accellerometer just to get something happening. I shouldn't worry so much about getting the best choice right off the bat. After all, the sensor you started with still managed to show a lot of interesting things

My tuning fork idea would be damped by connecting both legs of the fork together, using a material such as Sorbothane

That damping approach is based on all the times I've held one finger lightly across the forks to see how long it would operate while still being able to feel the vibration. I already know from having done that, that to only damp one leg will have a much slower effect on the other. Too slow for what I was thinking. It has to be both legs at once, connected together

I'm suspecting that there might be figure-8 motions if that doesn't work correctly, so I might add a set of guide rails on each side of the legs so they can't move sideways in reference to each other. The rails would be mounted on the lower leg and count towards it tuned weight. But that all depends on what happens when I put an accellerometer onto a tuning fork using a barrel as one of the legs

Have you ever just held a loose barrel vertically between two fingers, while striking the end with a wooden mallet? Depending on where you hold the barrel, there are holding points where the barrel will vibrate very strong & other points where it will act like nothing happened

I think it's possible to treat a barrel like a waveguide, and those active points are where the barrels natural resonant frequency has an end node. Sound waves can travel through the steel of a barrel at over 16,000 fps. So I think it should be expected that the shockwave of a pressure impulse driving a pellet might return & crisscross the pellets position many times before it exits the barrel

The barrel can vibrate with such force doing this experiment that just by feel, it's clearly not shootable like that. That had me thinking that when a barrel is not free-floating, but mounted in a more traditional half-stock style, that it really matters just how far down the length of the barrel you place an anchoring point in the fore end of a stock

Reply
Hector Medina
2/8/2019 09:57:16

Hmmmmm...
Two full length side guides?
Damping material?
Hmmmmm ...

Look at these guns:

https://www.ctcustomairguns.com/hectors-airgun-blog/how-a-semi-custom-gun-is-made

You have just described the Stutzen / Mannlicher stock.
And yes, all of the guns made with that architecture were VERY accurate.
I always thought that the stock's long wooden "fork" perpendicular to the normal oscillation plane had something to do with it.

Perhaps we need to think of a 430L Stutzen, though it would be too long to be a real Mannlicher.

The "figure 8" you describe have been fairly well documented here:
https://www.ctcustomairguns.com/hectors-airgun-blog/controlling-harmonics-in-a-barrel

As you can see from the orientation in the main spread direction for each group, the muzzle oscillates in all possible directions.

It is my theory that airguns' muzzles do not vibrate from the pressure force inside the barrel, but from all the mechanical aspects that go inside the compression chamber/mechanisms tube

Anyway, whatever you decide to do, keep us posted!



HM

Reply
Clicky
2/9/2019 03:28:00

That semi-custom with the Stutzen-Manlicher isn't really what I was thinking, but it is pretty cool. Maybe there's some small tuned effect in the stock? I couldn't say. If I had a way to upload an image, I could draw a quick concept sketch to better explain. But it does seem to be a bit off track anyways. I was supposed to be looking for advice or inspiration regarding building my own accellerometer. Then I had to go & get all kinds of crazy ideas! What I need to do is finish building the test rig I'm putting together. Until I actually do that, it's all just a lot of hot air. I hope it works...

Reply



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    Hector Medina

    2012 US National WFTF Spring Piston Champion
    2012 WFTF Spring Piston Grand Prix Winner
    2013 World's WFTF Spring Piston 7th place
    2014 Texas State WFTF Piston Champion
    2014 World's WFTF Spring Piston 5th place.
    2015 Maine State Champion WFTF Piston
    2015 Massachusetts State Champion WFTF Piston
    2015 New York State Champion WFTF Piston
    2015 US National WFTF Piston 2nd Place
    2016 Canadian WFTF Piston Champion
    2016 Pyramyd Air Cup WFTF Piston 1st Place
    2017 US Nationals Open Piston 3rd Place
    2018 WFTC's Member of Team USA Champion Springers
    2018 WFTC's 4th place Veteran Springer
    2020 Puerto Rico GP Piston First Place
    2020 NC State Championships 1st Place Piston
    2022 Maryland State Champion WFTF 
    2022 WFTC's Italy Member of TEAM USA 2nd place Springers
    2022 WFTC's Italy
    2nd Place Veteran Springers

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