Corey

Ahh, but what happens after the elastomer compresses? It rebounds and eventually makes metal-to-metal impact. Granted, this generates a pulling-type vibration, but your feet still feel it. Typical vibration isolation mounts have the vibration source fully isolated in both directions. The simplest way to do this is to have a bolt pass through a plate with rubber washers above and below the plate. This way the plate can move up and down without making metal-to-metal contact. Because the TD2/3 and this new plate have some preload, 100% of the small-frequency vibrations are transmitted from the board to the binding until there is adequate downward force to squish the elastomer enough to separate the metal-to-metal contact. Then all vibrations must travel through the elastomers and are somewhat damped out by them.

Awesome! Nothing looks as hot as freshly milled aluminum. :drool:

How about a fluid-filled shock spanning the two plates? That would add a whole new definition for damping! You could adjust a knob to change the damping effect too. Of course, it sucks because: -would need to be a large diameter version to work with the relatively small movements, or a bell-crank to amplify the displacement -stepping on it would break it -HEAVY! Ok, forget that idea. I'm extremely envious of having a mill to play with, though the screwdriver and metric crescent wrench are nice too. Thanks for the great thread showing the design/build process! By the way: You're not fooling us... There's no way you'd use a phillips screw on a Bomber product. Heck, anything other than a 5mm hex-headed bolt is a bit out of character!

So? How did it go?

I'm going to be autocrossing in sunny 60F weather this weekend but I'll be anxious to get home to read the review... Can't wait to hear the comparison! Find some rock hard ice if you can, that's the situation I want this board for.

The only skateboard I've ridden recently is a Loaded Vanguard, it could be pumped at surprisingly low speeds. I can get going on flat ground faster than I feel comfortable riding, which isn't saying much... ;) It took about an hour of trying things before the pumping motion really clicked, now I only push on uphills. At slow speeds I do more of a rotational thing, once you're beyond a brisk walking pace it becomes more of a 'pull with the front foot and push with the back foot' type of action. Ripsticks look kind of fun too, but I'll stick with my Loaded board just because I already own it.

No ball bearings or anything like that, just plain rock hard with a little bit of packed snow on top. The harder I pushed it, the wider the trenches got. I couldn't penetrate the ice layer to go any deeper, more G-force meant I just moved more snow off the ice layer. I haven't encountered anything like this in Colorado but it seems to be fairly common here as they don't groom very deep. I think I was just going too fast for the little SL board and my abilities. ;) In hindsight I should have dug out something a little longer given the good snow on top of the ice. It certainly was working most of the time though, I've never been approached so many times in one day to find out what the heck I was riding on and how I was turning so hard on crappy snow. I almost ran out of Bomber cards. Cool! :D

Haha, I've got my name in with Bruce! But I also want to become a better rider on any board.

Babelfish.yahoo.com translation: My quick and dirty interpretation: -the wrist and hands are flexible -making one part of it rigid is more likely to damage the other part -make a fist when falling to protect your fingers and to make your wrist rigid/strong

Bullwings - Looks fun! The front truck is at quite a steep angle, that thing must turn on a dime! Al - I didn't mention: I was really torn between the S2000 and a C5 Z06 Vette when I was picking this car. I picked the S2000 due to lower purchase pricing, but ironically the Vette is easier on tires so it probably would have been a wash. The S is fun too but there's something special about a V8! :) Nice! I worked the course for DS at Nationals, it was quite a contrast with the near-silent BMW's and ear-splitting Integras all in the same class. No pros or NT's for me this year, SCCA killed all the ones within a day's drive of central Canada. :( Good luck with the house purchase too!

You're dodging the question - AGAIN. :) And what does throttle-steering a car have to do with clothoid sidecuts? Never mind, I assume that's yet another tactic to dodge the original question. Please do spoon feed us 'children'. I've clearly laid out my hypothesis for why I feel that there is no relation between a vehicle driving on a clothoid-shaped road and a clothoid that travels with us on our snowboards. Now it's your turn to present something other than what boils down to "trust me, I'm smarter than you ever could be." This is the peer-review process that's common in science: 1. You state something as fact. 2. People review your work and ask questions. 3. You answer their questions with explanations that explain away their concerns. Step 3 is missing. Usually when step 3 is missing it means the 'fact' in 1 is incorrect or the person offering it really doesn't understand what they're talking about. Let me make myself painfully clear: It's not that I don't believe that some makers are using clothoids or other advanced geometrical shapes. I just disagree with your reasoning as to why a clothoid curve is the 'best' way to have a variable sidecut. I also assume that you are smart Bola, but I really can't understand why you are being so evasive about something you claim to know so much about. We all await your next reply, hoping it won't be yet another pedantic pat on the head or a listing of your credentials. Bola, are you going to SAE congress in Detroit? It's a longshot but it seems you have very diverse interests. I'll be there Wednesday through Friday, I'd love to meet up in the evening to discuss this and all things snowboarding with a fellow enthusiast.

Autocross: A-Stock class in a Honda S2000 3 weeks to our first event! :) I just signed up for Nationals in Lincoln, NE in September. Plus a Loaded Vanguard skateboard when the weather is nice. Also hope to ride my mountain bike more this year too.

Haha, no. ;) It was a regular profile, not the TrickStick one. His buddy had another retro-styled/knock-off board, I think it was an Avalance Kick type of graphic. I can't remember for sure though. Seeing the two boards side by side in the rack certainly stopped me dead in my tracks! I had to pull out my Iphone to verify which decade we were in. Neither owner knew they were copies of old board graphics. +1 for the Burton Fish, I really like that one.

Avoid the UPS Store, they charge a lot for the 'service' they offer. Usually 2 to 3 times as much as dropping it off at the UPS depot.

I saw a board frequently this year that looks like a Lamar Trick Stick.

Cool stuff. This is the stiffest slalom-style board F2 makes. It's definitely possible that I'm too heavy for it though. They only list a minimum weight of 154 lbs with no max weight: http://www.blue-tomato.com/en/Raceboards/F2-FTWO-Speedster-SL-Equipe-153-08-09/product.bto?product=300067500&category=20000&source=brand&brand=1 I use this board when I want to slow it down and rail tighter turns. It usually comes out in very hard conditions where falling will mean instant bruises, at least then I'm going slower when I do fall down! (I've got an order in with Coiler for an ice board to replace this one as I see these conditions a lot :)) Stance is around 19.5", height is 5'11", inseam is 33". Stance is about 1 cm forward of the insert pattern's center point but still behind the center point of the running length. I tried going both wider and narrower but really didn't like it. If it was a stance issue, wouldn't it be consistent in all turns? My wallet/change is in my left pants pocket, multi-tool in left jacket pocket, car keys in right jacket pocket. Maybe the uneven weight distribution is a factor? ;) :p Regarding "feeding the dollar"/weight transfer to the back: this may be the cause. I find this board has a pretty narrow sweet spot - which is REALLY fun when you get it right and annoying when you get it wrong. Maybe I'm just a bit gun-shy every now and then... ----- Once you start chattering, what do you do to fix it? I can't unweight the edge as I'm pretty committed to the turn at that point. My technique thus far has been to try to pull the board back in line, it works occasionally but is pretty unreliable. ;)

This past Saturday I went out on my last day of the season. There was an extremely hard base, basically rock hard yellow ice, with some firm but well-groomed cord about 1-3" thick on top. It was brutally hard in the morning but softened up enough to trust your edges a fair bit. I was the only one able to leave trenches on this particular run, though there are very few people in this area that are even aware that skis or boards can be carved. I was having a challenging but fun time exploring how much I could push it before the edge slid out and I went down. I was having an issue on probably 1 run out of 10, occasionally (both toe and heelside) the edge would start chattering/bouncing and I just couldn't stop it. I was able to catch a picture of my tracks from the lift: I tried all kinds of things to cause it and to stop it once it started, but I couldn't determine any kind of reliable way to do either. I think it may have started on the real icy spots, letting the board rotate a bit suddenly. Details that may matter: 205 lb rider, F2 163 SL board, Bomber TD2 w/TD3 e-rings, Deeluxe 700T boots, BTS with blue springs, chatter happens around 15-25 mph (wild guess). Any thoughts/advice on what may be causing this and what to do if you feel the board start chattering?

Well, we're all done here. :( But I had a great last day on Saturday! :D There was an extremely hard base, basically rock hard yellow ice, with some firm but well-groomed cord about 1-3" thick on top. It was brutally hard in the morning but softened up enough to trust your edges a fair bit. I was the only one able to leave trenches on this particular run, though there are very few people in this area that are even aware of carving. Board was an F2 163 SL with TD2.5's (Mostly TD2 except with TD3 heel receiver and TD3 e-ring/disc) and Deeluxe 700T. Pictures from my iPhone, sorry for the poor quality...

Nakiska Expression Session in Alberta: http://www.bomberonline.com/vbulletin/showthread.php?t=21915

Careful, someone will accuse you of hating small businesses... ;) You will get your Cateks eventually. TD3's: http://www.hardbooter.com/product_p/td3.htm http://www.allboardssports.com/trench-digger-td/ http://www.yyzcanuck.com/03_products/bomber_bindings.htm - in Canada

Globe and Mail article: http://www.theglobeandmail.com/servlet/story/RTGAM.20090327.wrichardson0327/BNStory/National/home/?pageRequested=1

Two from today, I was riding the singles line most of the day. #1 Me: Excuse me, would you mind if I joined you? Angry woman #1: Yes. Me: (thinking she thought I asked if I could join her) Ok, thanks. Angry woman #1: No, you can't join me. Me: Huh? Angry woman #1: I've had bad experiences with snowboarders. Me: Well, let me know if you ever want to have a good experience. Have a nice day. (I wanted to tell her to go f@#$ her hat, but thought better of it at the last second) #2 Standing in line for a two person chair with two acquaintances that are ski patrollers. Me to friends: blah, blah, blah... Oh, that guy's a single up there, I'm going to go join him Angry woman #2: No! You just can't cut the line like that, I've been watching people do this all day! It's not fair! Me to her: Perhaps you don't understand how this works. Me to ski patrol friends: Would you mind explaining it to her? See ya later! Angry woman #2: Why the hell would you ask your stupid friends?!? (turns around) Ohhh, I'm so sorry...

Sorry Bob, you couldn't afford my rates! :p I'm looking for something more in-depth than that. ;) Here's my issue: 100% agreed for a vehicle driving on a clothoid curve. The passengers will experience a gentler change in acceleration than a straight merging directly into a simple radius. How does that relate to a clothoid curve that travels with you on your snowboard? You can change which part of the curve you travel on with weight shifts, unlike the above example where the vehicle's change in trajectory is strictly defined by where it is along the curve. If we're talking about minimizing change in G-force in a carve with a board with a large radius at the tail and a small radius in the nose (regardless of what curve it is), you'd start the carve on the tail to keep the radius large and then shift the weight progressively to the nose to tighten things up mid-turn. Then back to the tail again to release G-force slowly and progressively. I don't think anyone actually does this! A rider can control the crush load with any sidecut profile, they just change the inclination of the board relative to the snow. Too many G's? Get the board flatter. Too few? Tilt it up further. Bruce, if it's not a trade secret, could you chime in with what method you use to blend from one radius to another on your boards? Few would say that your boards are horse****.

100% agreed here too, no baiting. I understand you are busy Bola, all I ask is that you spend as much time sharing your knowledge as you do calling others simpletons and stating your own credentials and past experiences. I spend a good portion of my days at work explaining technical issues to non-technical people, please do the same for us at BOL. I'd love to hear your rebuttal to this one question/observation I made above: Please, answer without calling anyone stupid or telling us how smart you are. Just write out some scientific reasoning how the two can be related and I'll be really happy. Maybe I'm completely misunderstanding what you're trying to say, just throw us a bone so that yyzcanuck and I can understand a link between the two.

There are a bunch of people that would love to learn more, but you've got some secrets that you won't reveal. I'd love to hear some reasoning of how/why a clothoid curve works on a snowboard sidecut, but without the name-calling and extremely defensive posture. I for one don't understand how the rate of change of acceleration in a vehicle driving on a clothoid curve has anything to do with a snowboard that has a clothoid curve for a sidecut. The clothoid-shaped road presents a simple 2-D problem that relates to human sensitivity to sudden changes in acceleration, the clothoid sidecut on a snowboard is a 3-D problem with some pretty funky inputs with two highly variable discrete point loads (our feet), changing edge angle, a decambering board, and dynamically deforming snow underfoot. I'm noticing this is a trend. You state something, when people question it at all, you call them idiots and leave the thread. It really leaves anyone questioning and the readers wondering if you really know something about this or are just an internet thug. Sorry, I hate to call you out as you obviously are quite intelligent but you're making claims that don't mesh with simple 2nd or 3rd year mechanical engineering principles. Lets drop all the internet tough guy stuff and have a real discussion about how the physical design of snowboards affects our riding and enjoyment of the sport. I'd love to learn more!