Chronicles of the Happy Fun Plate at the Bomber Factory

[fin]

I have heard th term "pedaling" used for this effect of twisting the board between our feet. So I am running with that term for now. Any other ideas on what to call this I am open.

I think the question is not that pedaling occurs (I believe it does) but is it a benefit? And I also ask the question again, are WE pedaling the board or is the board pedaling us? If we honestly are pedaling to effect the turn I would ask, what are you trying to do?

It is also possible that what we perceive as pedaling is actually us trying to resist the twist effect. So in the middle of turn, the board starts to torsionaly twist, to resist this we pedal in the OPPOSITE direction. So then the rider states "I am pedaling to effect the turn". Yes, you are but you are actually trying to stop the board from twist as apposed to making it twist. Two very different events.

Lets say you can create an angle of 3 degrees difference between the front and rear foot. (Once again pulling this number out of thin air, but if I clip in on a carpet floor I bet I can get this amount of twist no problem. Maybe more.) So if I can twist a board between my feet by 3 degrees using pedaling why would I want to change the angle of the edge touching the snow by three degrees? I just put a sweet 2+ degree side bevel on my board, I want all that bevel in effect. There is a chance I am now actually twisting my board PAST this 2 degree bevel, say to negative 1 degree. If I was on super hard conditions I would not want this to happen.

Now all of this is hard to measure and justify at this point. At that was the reason for the Torsion Bar aspect of the HFP, to take this concept to the maximum degree and see what happens. I am fully prepared to find out the results will go either way. But my feeling is it will probably be more of a taste thing: some will like some won't.

[Sinecure]

The snow at Mammoth this weekend was like morning wood. Nice and firm at first, but it softened up noticeably once the sun got on it and you played with it for a while. Hopefully the crew testing this coming weekend will have similar conditions. It definitely froze up over night and was staying nice later into the day than it was two weeks ago when I was there.

Its funny. I was looking at the original pics of the springs and thinking that they look cooler / more high-tech than the elastomer, but that they'd need rebound damping. I guess that was right. Would it work to make the edges of the HFP slightly higher, thereby accommodating thicker elastomer and maybe even more board flex before the HFP contacts the topsheet? I'm thinking the plate would have a profile more like this looking from the side --|____|-- where those vertical lines don't go so high (only has high as the dashes - my keyboard doesn't have a half-height vertical line), and the elastomer pods go where the dashes are.

As others have said, thanks Fin for including us in the development of this "product". It is fun and educational to watch the process.

Oh, and my son who is on his school's robotics team had a name for the spline thingy. It had the word key in it, but I can't recall. He described a version that would have only a couple of flat surfaces though - eliminate the splines. Sort of like the ends where you attach it to the HFP. I showed him the photos in this thread and he commented that they use mills/lathes like yours to make their robot parts for competitions.

[Arclite]

Oh, and my son who is on his school's robotics team had a name for the spline thingy. It had the word key in it, but I can't recall. He described a version that would have only a couple of flat surfaces though - eliminate the splines. Sort of like the ends where you attach it to the HFP. I showed him the photos in this thread and he commented that they use mills/lathes like yours to make their robot parts for competitions.

Sorta OT: what school does your son go to? My high school's robotics team just won nationals in the USA

El Camino Real

[Jack M]

:lol:

Thats strange, I think its totally adviseable. Its what might be refered to as "finesse".

Since it's much harder to prove a negative, I'd like to ask you to prove it's beneficial... what does changing the shape of the board <i>only between your feet</i> do for you, and how?

If Jack says so.

That's Sir Vice Administrator Jack to you! ;)

[BadBrad]

Oh, and my son who is on his school's robotics team had a name for the spline thingy. It had the word key in it, but I can't recall. He described a version that would have only a couple of flat surfaces though - eliminate the splines. Sort of like the ends where you attach it to the HFP. I showed him the photos in this thread and he commented that they use mills/lathes like yours to make their robot parts for competitions.

Woodruff key, perhaps?

http://en.wikipedia.org/wiki/Woodruff_key

[bjvircks]

regarding turning radius, scr and board length..... I'm putting togther a set of sketches that may help show what is happening and what CAN happen with the forces and shapes that affect board behavior. FYI... In a past job I did structural design for conveyor system scales which required a detailed understanding of how loading, suspended lengths and deflections affected system accuracy. I created a computerized simulation which allowed certain variables to be tweaked and you could watch how the deflections changed.

regarding 'pedaling'... I view its affect to be somewhat like changing the angle of attack on a wing. A canard-type aircraft has a small forward wing and a large rear main wing. The forward wing is designed to have a slightly greater angle of attack compared to the main wing. When a canard aircraft is approaching stall speed the front wing begins losing lift first which causes the nose to drop, causing airspeed to increase, causing the aircraft's main wing to continue to supply lift and helping to avoid full-on stall. In much the same manner, intentionally twisting the board section between our feet by pedaling causes a different 'angle of engagement' between the front section and the rear section. On a snowboard perhaps this is used to make certain the tip keeps its track by giving it stronger engagement while allowing the tail the ability to wash-out should things become overstressed. This is all just idle speculation on my part.... I only just learned to stand up on a board in my living room last week.

[Jack M]

five easy questions:

What is the ideal shape a board should assume in order to carve a radial arc (a section of a circle)?

Should the board have a consistent edge angle down the entire length of the board while carving?

What will happen to the board if you apply twisting and/or bending forces to it with your legs?

What shape and edge angle(s) will the board assume if you do this?

How is this good for optimizing edge hold on hard conditions?

I believe the HFP and similar systems are designed to help the board assume the ideal shape for carving, as well as provide suspension/dampening.

[dantheman0177]

Fin, just a little practical suggestion for if the HFP ever comes into production:

On the male half of the torsion bar you should put measurement grooves, so that it can be remounted as a whole without the need for a tape measure.

Just a practical suggestion from the pragmatic (read: super lazy) side of the planet.

[noschoolrider]

Jack, there are too many variables for easy answers:

<B>What is the ideal shape a board should assume in order to carve a radial arc (a section of a circle)?</B>

Doesn't it depend upon the design of the board and the radius of the radial arc? Some of the new boards have the stiffest point in the middle so the middle of the board will not bend outward in the turn and scrub off speed in a turn like a conventional board will, while some boards are stiffer in the nose and others are super stiff in the tail, and some boards have full rocker. So, wouldn't each of these different designs have a different ideal shape for each different size turn?

<B>Should the board have a consistent edge angle down the entire length of the board while carving?</B>

Is the surface of the snow perfectly smooth and perfectly consistent in density all of the time? Shouldn’t the rider make adjustments throughout the turn to maintain the appropriate amount of edge angle, pressure, balance, and rotary/turning force to complete the turn as efficiently as possible?

<B>What will happen to the board if you apply twisting and/or bending forces to it with your legs?</B>

If the board is designed to twist and bend, then wouldn’t it twist and/or bend where it is designed to, based upon the rider’s input and the forces of the turn?

<B>What shape and edge angle(s) will the board assume if you do this?</B>

Doesn’t it depend on <B>how much</B> the rider physically manipulates the board and how much the forces of the turn manipulate the board?

<B>How is this good for optimizing edge hold on hard conditions?</B>

Doesn’t optimal edge hold occur when the appropriate amount of pressure is maintained upon the appropriate edge angle? Isn’t it up to the rider to achieve this by maintaining the appropriate amount of edge angle and not over-pressure the board/edge (like when too much rotary is used or too much downward weight is applied) or under-pressure the board/edge (like when too much absorption/un-weighting is used)? So, if the rider makes adjustments that help maintain optimum edge angle and optimum pressure then wouldn’t optimum edge hold be achieved (wouldn’t that be good)?

<B>I believe the HFP and similar systems are designed to help the board assume the ideal shape for carving, as well as provide suspension/dampening.</B>

Some systems can be used to change the shape of the board (they can induce camber or rocker) and/or add or reduce pressure/preload on the board. Other systems are designed to allow the rider to have more input upon the board as well as provide suspension/dampening. The question is: Is the HFP going to change/effect the shape/performance of the board via the plates and/or torsion bar, or is it just going to make it easier for the rider do this in addition to providing suspension/dampening?

[Jack M]

you're over-thinking it. the answers are simple. for example: in order to carve a radial arc, ideally the board should assume the shape of.... a radial arc!

[noschoolrider]

Fin,

Regarding “pedaling”: I think that is the correct term because about 17 years I remember being with a group of pro riders and board testers at Mt Hood who were using that term and discussing the pros and cons of torsional twist. If I remember correctly, Mark Fawcett showed us the following techniques that he used:

1. When riding a board flat and straight at high speeds on a hard and/or uneven surface it becomes difficult to keep the board tracking straight so it feels unstable (especially a board with a lot of base bevel because there is little or no edge contact). The technique for correcting this problem is to lightly pressure opposite edges by slightly torsionally twisting the board with your front and back foot. Example: Use your front foot to pressure the toe-side edge by pushing down (weighting) your toes while at the same time using your back foot to pressure the heel-side edge by pushing down (weighting) your heel. Using this technique keeps your body more centered over the board so you can also leverage one foot against the other more effectively to assist in keeping the board going straight and you will not lose as much speed as you would if you set a full edge.

2. In some situations, while aggressively carving a turn the nose of the board will dig too hard/deep, which can cause an excessive loss of speed and/or a crash. The technique for correcting this problem is to slightly torsionally twist the board to reduce the edge angle in the front of the board by lightly pushing against the edge that is not on the snow with your front foot while maintaining the same edge angle with the back foot. However, in my opinion, this technique is unnecessary on a new school board with a decambered (extended rocker) nose because the nose is designed so that it will not dig too hard/deep.

Also, some snowboard instructors teach their students to torsionally twist the board as a method of turn initiation. However, some instructors find that method to be too slow (and confusing), and most alpine boards are too torsionally rigid for that method to be effective.

The problems with too much torsional twist is that the board can start to wobble while in a hard carve which will leave a wavy track in the snow. This is because parts of the board’s edge are engaging and disengaging as it twists off the pressure/forces caused by the turn and the rider’s weight. So far, I have never been on a board that I would describe as too torsionally rigid/stiff, so it would be interesting to find out if that would have a negative effect on the new school race boards.

[noschoolrider]

you're over-thinking it. the answers are simple. for example: in order to carve a radial arc, ideally the board should assume the shape of.... a radial arc!

Some of the new VSR boards have the stiffest area in the middle and because of this they do not bend as you would expect them to, and therefore they do not assume the exact shape of a radial arc like a conventional board does. However, they get the job done faster because they don't lose as much speed as a conventional board does.

So, the use of the word “ideal” depends upon what you are trying to achieve.

[Erik J]

Fin, just a little practical suggestion for if the HFP ever comes into production:

On the male half of the torsion bar you should put measurement grooves, so that it can be remounted as a whole without the need for a tape measure.

Just a practical suggestion from the pragmatic (read: super lazy) side of the planet.

Great idea! This is one of those "why didn't I think of that?" kind of things. It could be a simple number that tells you what your stance width is.

RE: the twist / pedal thing. While I don't fully understand what this does, I do know that I absolutely wrench the sh!t out of my board while riding aggresively, mostly on hero snow or softer snow. For me, it's fun to force the board around, bending, twisting, hopping, etc. It could simply be that it's my need to be dynamic while riding. Setting an edge and riding long curves till the board comes around gets old for me. I need more action. On ice, my movements are very subtle and more calculated with more gentle pressuring etc. Ice is more challenging for me and makes me really appreciate the days when I can go full throttle. I'd like to understand more on this subject. I'm not one to do something just because, I need to understand the details.

[noschoolrider]

Jack-its almost like you assume that a snowboard will only bend into one shape. Work it a little harder, it will give you more that what the specs indicate.

Ouch!

It’s easy for most people to roll the board on an edge and let the board make a turn the size that it’s side cut radius is designed for. But, that is being passive because the board is the one taking you for a ride.

However, as Mark has already stated, if you have the skills/techniques then you can manipulate a board so that it will make a bigger or smaller carved turn than what it’s side cut radius is designed for, whether you’re on hero snow or ice. These are some of the skills that racers need to be competitive!

[trailertrash]

Proof is in the pudding. Come on out next year to the SES and Ill show you just how short a 197 burner or any other gs board for the matter can really turn. I am a feel rider not a talk a **** load and think about about it for hours rider. I dont draw cute diagrams and pictures, consult the alpine snowboarding engineering team, or run it through a super computer to anaylize and test it out. I go out and ride, alot. I have put in the time and mileage to know how a snowboard works. And when I ride I change it up always. I twist my feet, hammer the nose, surf the tail, anything to get the results that I want, not the results that the snowboard wants to give me. Snowboards can be quite versital if you can figure out how to extract that versatility. Ever railed turns on a 156 Fish with TD3 on the hard pack? You can, and you can make that funny looking board turn long if you can figure out float.

wouldn't it have been easier to just type "I don't know"?

[Jack M]

Jack-its almost like you assume that a snowboard will only bend into one shape. Work it a little harder, it will give you more that what the specs indicate.

Well of course. But then you're only using a much shorter portion of the board, often half or less. Not the best idea on ice. On good snow, sure.

It’s easy for most people to roll the board on an edge and let the board make a turn the size that it’s side cut radius is designed for. But, that is being passive because the board is the one taking you for a ride.

Only if one doesn't know how to angulate.

[Jack M]

Some of the new VSR boards have the stiffest area in the middle and because of this they do not bend as you would expect them to, and therefore they do not assume the exact shape of a radial arc like a conventional board does.

Sure about that? Considering that a conventional radial sidecut board does not take on a radial shape when decambered, it stands to reason that some <i>other</i> shape, or shapes, <i>does</i> become radial when decambered. Or when decambered by being pressured unevenly..... hmmmmm.....

[noschoolrider]

Only if you don't know how to angulate.

Static angulation is pasive, and the addition of dynamic angulation by itself (making angulation/balancing adjustments while in motion) still makes a passive turn because there is no muscular turning force involved. Used by itself, angulation will not significantly effect the turn radius the way Mark and I have been discussing it.

[noschoolrider]

Sure about that? Considering that a conventional radial sidecut board does not take on a radial shape when decambered, it stands to reason that some <i>other</i> shape, or shapes, <i>does</i> become radial when decambered. Or when decambered by being pressured unevenly..... hmmmmm.....

Well, I recently finished several weeks of testing on 3 of Bruce's VSR prototypes and in my feedback to Bruce I said, "the middle of the board does not bend outward in the turn so it does not scrub/lose speed" and Bruce confirmed that this was a design trait that was taken off a modern race shape and he also said, "It is as you figured not designed to scrub speed off as a normal FC board."

So, you can take this debate up with Bruce if you want.

[Petrol]

...Not totally killing the idea right now, but it would take another stage of intense engineering and machining to create some spring pods with built-in damping. I can see it now, eight tiny dashpots with adjustable rebound and compression inside and a ride height adjustment. Like a set of expensive coil-overs for your car!...

or maybe cast urethane filled coils???

(he says at mid page 6... I gots to get back to the reading)

...So after a day or two of testing I re-machined all the pivots to very tight tolerances and now the two Main Plates can barely move relative to each other. Most play now is in the spline interface.

Perhaps you could machine the spline reciever directly into the forward mount, tossing the hollow tube and substitute a swapable torsion bar (differant diameters for differant stiffness) set up?

[tinks]

IF[/b] you wanted to increase the camber of the board, this could be accentuated as well with snowstix attached to the front of the forward HFP and the back of the rear HFP. It is similar to a ski binding tyrolia had a few years ago that allowed you to tension the ski at the waist to increase or decrease camber. A totally tuneable system.

later,

Dave R.

Hi Fin ,

Looks like you have a fun project going on; or maybe I should say, a Happy Fun Plate project going on. This thread on external suspension systems as you can imagine is something I have played with a lot. In 1991 my external suspension system, SnowStix was the first system to be marketed to the Ski and Snowboard industry. The article that was in the SkiTech Magazine, September 1992 was entitled “SnowStix Delivers External Suspension’’. Since that time all the major ski manufactures have all followed and made some sort of external system. I mention this fact so people know that there was a time when I was the only one talking about suspension and being told damping vibrations and deflections could all be done within the ski or board.

The first product I made for racers back in ‘91 pre-4x4, was custom hand cast urethane cants for the Cross M race team. They went under the old Fritch toe and heel mounts. Then later some guys had me make some for the Old Catek Rino Bindings, instead of stacking all the washers with the little rubber on them, all this still pre-4x4. Fin, I love what you are doing bringing everyone along for your project and it is great to not hear any one say there is no need and that boards can do it all.

Fin, HFP + SS; the ultimate interactive Super Suspension System.

I see some possible attachment points. It sure would be easier than the Snow Stix adapter plate I made last year for the Hangl and Vist Plates. I will attach the photos so you can see how it looks. I will also try to get the photos out of an e-mail Jasey sent me of the Kessler he mounted Snow Stix on. They mount off of the binding plate . I would love to have you send him a HFP + SS all built in and ready to go . His results have been good. The only thing was the binding mount if you could have a built in mount on the HFP that accepted Snow Stix that would be so cool. It would save me having to make a mount adapter. Would love to send you a new set of carbon SnowStix to play with. Think of the possibilities: camber adjustment, tip and tail torsion flex control, adjustable binding suspension , binding to binding torsion control. All done sleek and sophisticated. Would like not to make any more adapter plates for Hangl and Vist just have one nice system that receives Stix.

I hope what I have said makes sense and that its taken positively. Still a little gun shy about saying things on BOL. Anyway would love to introduce people to full suspension on an American Plate system.

And one suggestion to try on your adapter plate for other bindings, slot the two front anchor points and run p-tex under the interface.

Having a hard time sizing the photos .I will send them later.

Tinks.

[www.oldsnowboards.com]

aforementioned photos of Jasey's Kessler Snow Stix proto type

[www.oldsnowboards.com]

More photos of the Hangl -Snow-Stix adapter plate. Note- newest snow-stix design.

[Donek]

All the board builders I've discussed twisting of a board with have refered to it as pedaling. It is a very effective technique for beginners if you are able to describe it correctly. Ending a skidded turn can easily be accomplished by twisting the board to disengage the edge at the shovel. This will reduce the drag at the shovel and cause the board to head down the fall line. Retaining the twist as the board is skidded into a slide on the opposite edge will help bring the board across the hill. Relaxing the twist will make the board slide evenly. Repeating the same action (reversed edges) will enable a beginner to complete the next turn. This is an extremely effective teaching technique for a beginning rider who is spatially aware or has an engineering mind.

Everyone has experienced side slipping a mountain has undoubtedlt used this technique to control the skid and end it. Next time you're on the hill, make a conscious effort to determine what subtle movements are occuring under your feet to determine how you are controlling the direction of your skid.

I don't know a single builder who doesn't consider pedaling to be an integral aspect of board function. At the higher levels, it becomes more ambiguous though. In my experience riding both carving snowboards and carving monoskis, I have observed the lack of twisting control in a monoski makes it far more difficult for me to carve a turn. When Fin rode his HFP, I was very curious to see if he would experience simply tipping over and continuing to go until he hit the snow. It did no happen, which indicates to me that there is more to the differences than twisting.

Jack - you sound like me 10 to 20 years ago. I was convinced that there had to be an absolute perfect shape. I built a board that was intended to accomplish the perfect single radius carve at a specific speed and anglulation. Pogue rode it and hated it. Shortly after that, it occured to me that no matter how much you try to control things through shape and flex, the rider is dynamic, so I tried to understand how he can change things. I developed shapes that created edge pressure where it needed to be, while giving the rider the ultimate control over turn shape by bending the board. Downweighting was the key feature, but the riders ability to manipulate the board between his feet is undeniable, so the shapes worked to allow this without negatively affecting the turning system. Today, looking at the variable sidecut radii and flex patterns being used by other builders, things are different. The concept of perfect edge engagement along the entire board is impossible given the dramatic differences in turning radius from the tip to the tail of the board. I never would have imagined it would work, but having ridden it, I've been startled by how wrong I was. It was very important to take into account these variables in designing flex patterns, but they can be made to work extremely well. There is no such thing as the perfect shape sidecut, or bend. They simply have to be engineered to work together while allowing a dynamic rider to correct for their innacuracies.

[noschoolrider]

Hi Sean (Donek),

Great information!

I'm looking forward to riding some of your new shapes especially when you apply this technology to boards built for lightweight riders like me.

I wish you the best of success,

Don Richter