Wind flag disasters

[mks]

I've been meaning to do this for a while. Here are some pictures of wind flag prototypes that did not work out. The first I had high hopes for. It was intended to provide a large, integrated display to the shooter with clear information on wind direction and crosswind speed. It does that, but is so slow as to be unworkable. The right angle drive has a lot of drag, and all the parts contributed to large inertia.

The second was meant to show wind direction, especially quartering direction, better than single vane flags. The square cross section was really unstable (meaning it wagged like a Lab just out of the lake!).

If anyone else wants to embarrass themselves with pictures of their failed experiments, or offer advise, please do so. I've had fun trying new ideas.

Cheers,
Keith

 

[Boyd Allen]

I once new an older fellow who was an exquisite craftsman. He made some super light wind flags that would turn if someone coughed at the firing line. (OK, I am exaggerating a little.) The vanes were small, light, and their leading edge also formed the pivot bearing. The counterweight was a dab of lead that was some distance in front of the pivot on a slim piece of music wire. The only problem was that they never stopped, "jitterbugging" around a heading more or less continuously. If the counterweight had been closer to the pivot, it would not have had so much leverage or developed so much momentum during a change in heading. Of course it would have had to be heavier, but that would have been offset by the reduction in velocity. If the vane had been farther from the pivot, the force of the wind would have had greater effect per unit of area, because of the increased leverage on the total rotating mass. In any case, what looks goods from a static perspective, may not work out in the dynamic. What we learn from our mistakes, reduces the likelihood of our repeating them.

Today, I stopped by an unlimited match at the Visalia range. There were 26 competitors, and only one daisy wheel (propeller) to be seen in the entire field of flags. The trend is to simpler flags. Even though the wind was highly variable in the afternoon, the top seven or nine (I forget) hundred yard aggregates were in the teens. Of the flags that I observed, those that Rick Graham makes seemed to stand out as being among the easier to read.

 

[mks]

The counterweight was a dab of lead that was some distance in front of the pivot on a slim piece of music wire. The only problem was that they never stopped, "jitterbugging" around a heading more or less continuously. If the counterweight had been closer to the pivot, it would not have had so much leverage or developed so much momentum during a change in heading. Of course it would have had to be heavier, but that would have been offset by the reduction in velocity.

I made the same mistake with the square flag. As you can see in the picture, the counterweight is just a couple of nuts on a long carbon fiber rod. Light weight, but higher inertia than a heavier weight closer to the pivot. Polar moment of inertia is proportional to mass times distance squared. So if the distance is cut in half, the mass must be twice as great for static balance, but the distance squared term gives a factor of 1/4. Inertia is cut in half, in spite of the greater weight. So the square flag should work better with a closer counterweight, but the square shape is inherently unstable in crossflow. I should have known better.

I do like the way it displays direction - all orange or all green for exact cross wind, then it begins to show either some black or white for quartering winds.

 

[Boyd Allen]

My double vane Hood flags have vertical stripes on the inside of their vanes that help me to see small differences in quartering wind angles. The one issue that I have left to resolve is a way to have my pivot shafts perfectly vertical. I am going to do some experimenting to see if this is an advantage. I think that it will be.

 

[Gene Beggs]

Yep, it's fun !

Hi Keith

You've certainly been thinking. I remember you saying once, "Experimenting with wind indicators is fun" or something like that. and I agree.

My benchrest career began in 1987 and since that time, I have spent a great deal of time and money trying to develope a better way to read the wind. As most of you know, the Beggs Wind Probe has been my contribution to that end. When I set out down that long road, I wanted to develope a device that would obsolete and completely replace conventional wind flags; a device that would sense both wind direction and velocity and combine the two into a single readout called crosswind component. It took about ten years of trial and error to perfect the wind probe and I believe those in use today are darn close. They do exactly what I set out to do with one exception, they will not and do not obsolete and completely replace conventional wind flags. I'll try to explain.

My friend and mentor Charles Huckeba was quick to recognize the advantages of the probe and began using them long ago but he always used them a bit differently than I did. Charles has always and still does to this day, use only one probe per 100 yards placing it near and lined up with a conventional flag at fifty yards. He relies on the field of vanes, ribbons and daisy wheels to tell him what is going on over the range and refers to the probe before pulling the trigger; sort of using the probe to tell him when not to shoot. Mike Conry does the same thing. You can't argue with success; however, there are those who do not like the probes, regarding them as just something that's in the way. Among those are Gene Bukys and Mike Ratigan. Sorry guys, I had to tell the truth but I must be quick to say that I still love you.

I believe it was Yamaha back in the sixties that coined the phrase, "Different strokes for different folks." That certainly applies to benchrest; doesn't it?

After all these years and no small amount of money blown downrange I have concluded that Mike Ratigan has written the best treatise on wind flags and reading the wind. His simple, inexpensive, easy to read flags are in my opinion the way to go. If you haven't read Mike's book, "Extreme Rifle Accuracy" you are missing out on some priceless information. Tony Boyer's book is in the same category. This is not to say that the Wind Probe is not useful, I'm just saying the probe is a valuable addition to but not a replacement for, conventional flags. I think about seven or eight of Ratigan's flags and one probe placed at fifty yards is one helluva' combination. Others may disagree.

Keith, keep thinking man, that brilliant mind of yours is awesome! We are lucky to have you in our sport.

Best regards

Gene Beggs

 

[alinwa]

My double vane Hood flags have vertical stripes on the inside of their vanes that help me to see small differences in quartering wind angles. The one issue that I have left to resolve is a way to have my pivot shafts perfectly vertical. I am going to do some experimenting to see if this is an advantage. I think that it will be.

Boyd, I have a set of Don Jewell's flags which have ball joints and level-plates......... maybe not PERFECTly level but perty dern close.

Now,

that said I don't like the ball-joints. They're creaky and cantankerous and having two such like items in the same vicinity produces some, ahhh..... friction. Friction and sulphur. So I'm switching to this http://www.amsalesinc.com/index.php?main_page=product_info&products_id=35 sort of brackets. Stop by your likal concrete tooling supply house and checkidout

al

 

[skeetlee]

Thanks Gene. I wish you would post more often, i do like reading what you type. I have seen mikes flags and they look homemade, and if one didnt know better, one might wonder just what the heck they were. LOL!! Mike does keep things simple, and thats were most of us fall short. I know i sure do.
I have a set of graham flags, that have been sitting OUT on my range for exactly one year next week. I never take them down,nor do i touch them much, except to clean the pivot area once in a while. Ricks flags have not fadded one bit, nor do they look any different than they did the day i bought them. I get some real nasty weather on my farm, and lots of wind. Lots of 100+ degree sun as well. Ricks flags are the bomb!! I would recommend these flags to anyone who might ask. I couldnt be more pleased.
There are a couple other flag makes on the market who have some flags i would really like to try. The problem for me is that every time i think i might like to try a different flag, i start to think about how well i like my Graham flags, and i ask myself " will this be money well spent?" Ya maybe, but i am not much of a gambler, never have been.
One project i am going to do since my range is so wide open, is to make myself a wind probe. I will do this project this winter, after i build a new foundation for my Lathe. I really like Genes vane, and i am more than sure its the best one on the market, but they are not cheap. For good reason i might add.
On my range i get the full value of a push or a let off. It is simply amazing how much a bullet will move when you cant even hardly see a change in the flag. 4mph to 5mph will nail your ass on my range. The down side to this will be me over compensating on a different range with my holds. Actually i try not to hold much but there are times when we are left with no choice. Just thought i would share! Lee

 

[Pete Wass]

I currently have 4 sets of flags, two of which are the same but different sizes, small &Large. I have been round and round, Dasies vs Balls, etc, etc. I am currentlly using Dasies with two sets of the 3,(4). I also use 2 probes. I set one at 40 or so Yds and one @ 80 or so when shooting 100 yds. I won't shoot until they both agree. I do the same @ 50 yds . I set one probe at 20 and the other at 40 and wait until they agree. I have been using probes for a very long time and can not imagine shooting without them. I was sadned to hear that Gene has given up on making them. There are other Probe-like indicators out there but none of them work quite like or are of the same quality of the origional. Glad I have held onto mine.

 

[frey]

Not a Disaster

To avoid failure, I just copied Rick Grahams design.
I shot over Ricks flags for 3 years and still own the set of 5.
But found with the light tails I like to use, they would often show the condition before the flag moved.
So I replaced the heavy wood ball with a hollow polypropylene ball,
the aluminum shaft with a hollow fiberglass shaft, and
the standard 4mm coroplast with a lighter 2mm material.
The "homemade" version is about half the weight as the original.
They can get a little jittery, but work good here in the SE where the winds aren't so bad.

And these little things are great for getting your pivots plumb

 

[ReedG]

Everybody has an idea. When my nephew and I built our flags (actually, rebuilt, as Mickey Coleman sent me a bunch of well-used flags that needed some TLC) we made Delrin pivots on my little Grizzly lathe. If you use a 3/16" shaft, the roller bearing off router bits are a slip fit and we countersunk them into the bottom of the pivots. It seems that even when the stands are not perfectly plumb, they still turn very free. Can't upload the picture.

 

[mwezell]

Two things that I have found to be true after extensive testing and building flags is 1) frey, if you'll balance those flags just a tad tail heavy, they won't be as jittery. A stable flag is the result of proper balance between the center of force and the center of gravity. Yes, it is a bit more sensitive when balanced like you have yours, and that's great in a trigger pulling contest, but is detrimental in normal to heavy wind. Weight is critical to maintaing sensitivty. You're on the right track with that. And 2) Reed, I've never found a bearing that didn't actually slow a properly built and balanced flag down. Weight and friction are obviously critical here.--Mike

 

[RJG]

Sorry to butt in here, but whenever someone puts out there the “balance them heavy toward the tail” thing I need to set the record straight, otherwise I end up explaining this over and over to guys buying flags. Keep your Graham flags well balanced with the tails you are using attached. No need to have Graham flags working in an out of balance condition as the “fishtailing” or “jitterbugging” or “wind shield wiper effect” were long ago designed out of my flags. Thank you

 

[Wilbur]

Pretty simple concept. If a flag has enough tail surface to overcome the "nose" surface and the resistance of the pivot it will work just fine. The reason some flags work better "tail heavy" is that extra inch or so of leverage goes a long way to overcome things that might not be optimum.

 

[mks]

Rick,
Having watched them at a number of ranges in my area, your flags are indeed stable. In your experience, what is the key to achieving stability in a balanced flag? Is it, as Wilbur observed, having a long enough tail for "leverage?" If one keeps the flag balanced, adding more tail means more counterweight must also be added. The extra weight tends to increase inertia, which decreases stability. Is the effect of the extra leverage greater than that of the extra counterweight? Seems that way with the flag ideas I have played with.

Thanks,
Keith

 

[SGJennings]

Rick,
If you will read carefully, you will note that the poster said that he had copied your flags but changed several things. In other words, they are simply not your flags, they are a completely different animal. So, comments about balancing tail heavy might be spot on, way wrong or indifferent. There is no way for you to tell.

 

[mks]

Pretty simple concept. If a flag has enough tail surface to overcome the "nose" surface and the resistance of the pivot it will work just fine. The reason some flags work better "tail heavy" is that extra inch or so of leverage goes a long way to overcome things that might not be optimum.

Wilbur,
I think you are correct. But an unbalanced flag also has more drag in the pivot. With the typical pointed-post design, the flag pivot rubs the side of the post if the flag is unbalanced. The extra resistance also tends to stabilize the motion. So long as the resistance is not so great as to cause the flag to "stick" in one position and not respond to a switch in wind direction, it can actually be an advantage.

 

[SGJennings]

There is more to it. There is center of pressure vs center of mass to consider. From developing flight control software for the F16 and F22, I know just enough to be dangerous. I bet that I could easily modify a flag such that it would swap ends completely.

 

[mwezell]

Sorry to butt in here, but whenever someone puts out there the “balance them heavy toward the tail” thing I need to set the record straight, otherwise I end up explaining this over and over to guys buying flags. Keep your Graham flags well balanced with the tails you are using attached. No need to have Graham flags working in an out of balance condition as the “fishtailing” or “jitterbugging” or “wind shield wiper effect” were long ago designed out of my flags. Thank you

I'm sorry, but this is a critical part of flag design and there are no shortcuts. The center of pressure(or force) must be behind the center of gravity. No different than airplanes. This is basic to aircraft design and is indisputable. How you go about achieving that is irrelevant, as long as you do, but simply adding more area is adding weight and slowing the flag down. Anyone interested can research this for themselves by googling vertical stabilizers. Something that often goes without thought is the tail. Whether you use sail tails or whatever, it has drag and that drag increases with wind speed. This offers more "effective" tail weight as the drag increases with speed, thus making the flag more and more tail heavy, effectively. So, if you balance a well made flag perfectly based solely on it's center of gravity, it's not that way in use, and changing or altering the tails will have an affect on them because of this. Now add a spinning daisy or pinwheel into the formula and it has a similar effect on the front. The simplest way of dealing with this is to not use one but that's leaving a valuable tool to wind reading off the flag. I don't use garden style daisies...they're way too heavy for starters, and tend to start and stop slowly and inefficiently, as well as just add mass to the flag...which is a BAD thing. Also, they don't offer much in terms of usable feedback to the user. The pinwheel I use on my flags weighs just over 1/3 of that of standard garden daisies and is muli-colored. This gives it the added benefit of clearly and almost instantly showing angle changes by displaying more or less of each of the two colors as it spins and changes angle, very precisely I might add.
Friction and weight are the enemy in a good flag, so I use small diameter pivot pins and teflon adapters, not delrin or aluminum to reduce friction, and use the lightest and most durable materials I can. They are made of carbon fiber and fiberglass clad in vinyl. Even the pinwheel is of fiberglass. You can break it, but it's far more durable than plastic garden daisies and coroplast, and the flags won't take on water. Total weight of my flag, with sail tail attached is about 126 grams. A standard garden daisy weighs about 100 grams by itself.
Rick, I do consider your flags among the best.

 

[mks]

I bet that I could easily modify a flag such that it would swap ends completely.

Greg,
No need, I have already done this.

For a balanced flag, the center of mass is always at the pivot. It seems to me to be more of a center of pressure (CP) versus rotational inertia thing that is going on. One can go long on the CP, which will stabilize even the heaviest flag. Or one can go light inertia-wise and get away with a shorter CP, up to a point. A flag with short CP can swap ends if inertia keeps it rotating past the point of wind force balance. That's what my old flags did occasionally.

Interestingly, a very light flag with short CP can spin in place because that's what the wind is actually doing, i.e., the flag is in a vortex or shear layer and is light enough to respond to it. I've seen yet another rejected prototype do this in the shear layer alongside the wake from my air conditioner. This only tends to happen with large-bodied flags, like my styrofoam cylinders, which give the shear force a moment arm to turn the flag.

Cheers,
Keith

 

[mwezell]

Pretty simple concept. If a flag has enough tail surface to overcome the "nose" surface and the resistance of the pivot it will work just fine. The reason some flags work better "tail heavy" is that extra inch or so of leverage goes a long way to overcome things that might not be optimum.

Wilbur, this is simply not true. For a flag(or plane) to be stable, the center of pressure must be behind the center of gravity. This is evidenced by how a plane gets loaded with cargo. Again, how you get there is another subject. Google and aeronautical engineers are my friends.