BraceMaker

@wtrski6

Recognize the pin? http://www.jagersport.com/images/MountingplatesHO.jpg

@mr_pretzel - I think the argument exists that so long as the system you use is similar front/rear, and not overly tight that you will either release both or neither.

So double animals set such that both bindings take approximately the same force to pull up out of would be OK, tight front animal and RTP, or tight rear animal looser front etc. could in theory increase risk.

about the only binding systems that actually do what you describe are either double boots on a shared plate, or the FM 66 which has only the rear release pin, and two plates which interloc in the middle, front plate technically is held down by tension through the plates from rear pin and a small section of plane velcro (not dual loc) which is more or less to allow you to jump off the platform or a dock.

So from a different industry, we do laminations in a different manner.

First we usually have a positive, and we build around it, and then remove our positive. So we do an inner bag (PVA) which we vacuum to the positive. Then our laminants, which are combinations of fibers, carbon, glass, Spectra etc. Once the dry laminants are layered appropriately, we add the second outer PVA bag, which we tape off, and apply vacuum, then we mix our resin, hardeners, pigment, etc. and pour into the layers from one end, while under continuous vacuum.

Then using the outer PVA bag and some nylon stockings, we string the resin into the layers to let it saturate and impregnate the fibers. Once it is sufficiently saturated, the source of resin is blocked off/clamped, the excess is strung to one end where excess fibers exist waiting to be cut off at a later point, vacuum is increased if you want to compact the fibers further, and the system is allowed to cure under ambient temps.

Our resins are usually acrylic or modified. Our positives plaster or expanded foam. No cores however.

Idea 2.... Pneumatic actuators attached to anchors - self retracting ie. PVC pipe homemade actuators of X-length (x being how far you want to suck the anchors under) Under pressure actuators extend allowing bouys to surface, when pressure is released internal spring retracts....

Boom.

Idea 1.

Neutrally sinking bouys - balanced to eventually sink.

With individual anchors, and sub bouys constructed of a bucket with sufficient weight to sink the ball, plus an airline, and a vent hole in the top. SUCH - that during use regulated airflow from a landbased compressor fills bucket with air, which slowly trickles through top during use. After skiing shut the valve and the air eventually self purges and all balls submerge. Time to ski, valve opens course rises, compressor runs ever X minutes.

Skiing is usually < not skiing if you are worried about submerging a course.....

Considering Inserts - I've had great luck at work using 8-32 T-nuts, using scrap plastic I heat them up and press them through a drilled clearance hole such that the "teeth" are embedded, the barrel is clear. Then I pack the threads with clay/plumbers puddy and laminate them in place for solid anchors.

I know D3 has a "screw retention plate" they laminate into the Custom X. Could be a worthwhile direction if you aren't 100% on where the binding should be (atleast the RTP). Quantum goes the otherway and gives you 4 and says use their binding....

@thager

I think we're in the infancy when it comes to binding products, and skis in general. If half the $$$ spend on downhill ski bindings/tech filtered into slalom skis, the products would be well ahead of where they are. But the fact is, we have a small industry, with EXTREME forces.

My original switch to double boots occured after a highwrap front RTP spiral fractured my femur. Fact is, if you fall going through the wakes with enough rotational force, a heel will come right out of an RTP and a foot will stay right in any wrap binding. So when I look at a system rotational release is a priority. Either it needs to trap both feet, or it needs to release consistantly with torsional load when you have only one binding. What does that leave in terms of product?

Certainly the Goode doubles, the Fogmans, The FM dual boot systems, many of the Radar products. Of course all of these if you let the rear heel up will not release, for instance if you do not tighten your ratchet straps on the back binding and your heel comes up 3" you can now fracture your front ankle before your rear binding lifts up enough to disengage the release unit.

On a Front Boot/RTP you have the same scenario but most of the front boot only systems are pretty good in that crash "mode" OTF in reflex RTP is a release, OTF in Goode Single is a release if the heel interloc is set properly, OTF in an E-Series is a release, OTF in a Revo is a release, OTF in a wiley's front Highwrap RTP is a release. Again when all are set properly, wetted prior to skiing blah blah blah.

Danger mode? Rotational loading. Reflex+heel adjusters = locked in during rotational load, same with Revo, Wiley's, Goode, etc. etc. What front binding allows rotational release consistantly???? I cannot think of any. Hence if you do not have both feet in and locked down you have rotational forces with rotational injuries, spiral fractures, severe sprains etc.

To me, you go double boots after an injury because you lost 2 years hobbling around on crutches with fixators, therapists, and pain. We have far to go.

Wally skier really figured out the issues with the previous sinking slalom course - Accufloat irrc?

Instead of using an integrated weight/air chamber that sunk to the bottom, the wally skier system uses separate ballast bags, hung below the course balls on a 1:1 ball/ballast set up.

Each ball then also has an air chamber, which combined with the inflated ball lifts the arms up.

The next improvement that Wally made over accufloat is that his air bladders are flexible, not rigid PVC. He uses a reversable diaphragm pump, so that you can use it to put air in and raise the course, but when used on vacuum mode it sinks quicker AND removes water from the system. Such that if a component/junction does link that water won't accummulate in rigid floats, but instead is sucked out of the system through the pump, which the bags deflate and allow this to occur.

Combined this means a course that can be positioned in variable depth water, as you can adjust the length of line to the ballast bags such that all the balls drop 5-8' underwater, and when you pump it up they all rise the same distance before the balls break the surface. Meaning = tension on line, no bowing etc.

If you wanted one that was mechanical you add a few issues. Firstly, you need to pull EVERY ball down. So assuming you aren't using PVC booms, but solid anchors, you would need to run pullies and ropes to subbouys at every station, the anchors would need to be very secure such that the system did not foul. I would probably consider then running a flexible tubing such as PEX or irrigation tube from every bouy to a centerline area with your cables run inside individual tubes. You could probably branch off such that each set of balls (boat guides and turn ball, gates etc.) pulled off one line. But you'd have to be careful to set all the slack properly. This to me means adjusting at the ball, and probably using crimps such that they would all "stop" at the surface under sufficient tension to stay put.

I would wonder if instead of buying prepreg, you could wet out your fibers, roll them in something like a PVA sheet, and toss in a freezer to delay the resin, then lay up so that last layer wasn't working so hot?

RQ or E.Lee, willing to share any insider secrets in regards to shaping your first core? Did you start out by looking at a commercial ski, then reduce dimensions across the board by the thickness of your lay up? Or did you just start with making a core and going right to working on your lay ups?

Also edge finishing, are your edges ground to shape post lamination? Or how do you get a good clean edge? Just rely on vacuum to draw it around your core? Or pressure into a mold?

Interesting, I have never wetted out a fiber lamination prior to vacuum processing. In terms of I do my lamination under vacuum then use a string to distribute the resin evenly and then increase the vacuum to compress the fibers.

I need to try some different techniques, but they all sound messier.

@rq0013

Are you shaping a core, layering your fibers dry, then bagging and stringing resin? Or are you doing a wet lay up, bagging, and then drawing the vacuum?

Benefits of not having to make molds, but it would seem accurate hand shaping of a core would be problematic, having seen guys do surf board cores with belt sanders and lamps, it is pretty impressive when they come out perfectly symmetrical.

UNF or UNC are "Unified" threads, F are fine, C are course. @Wayne is correct skis usually use a Number 8 UNC, which is a Number 8 32 threads/inch. Or 8-32 machine screw.

I don't think radar uses a number six, as most bindings have holes that are for the number 8 size.

A number 8 UNF for the record is an 8-36 if you consult "thread charts" you should be able to pull that info.

Has anyone done any comparisons of "back of binding" to "ankle center" position across binding types?

This is just something I was noticing switching some binding parts around the other night doing some "end of season cleaning"

If a Wiley boot has ~5/32"+2(1/8") overlays you have about .4" of material that you measure behind the heel as it were. Measuring a molded intuition liner and the thickness of the rear plastic on a hardshell I'm coming out about .3", which I suppose varies depending on the size of shell compared to your foot, and the size of liner (how much spare material there is during forming).

Likewise I would assume many individuals who wear a rubber high wrap have different ankle joint axis (AJA) inside the highwrap, fwd. backwards. Which means that the AJA varies within the boot, I would imagine significantly, particularly if you consider the foot "fits" by pressing forwards off the back of the heel of the bindings some distance.

So why do ski manufacturers do baselines to the back of the boot instead of center of ankle!

Thank you for your consideration(s).

I'm with SkiJay, although another idea would be to use some longer stainless screws, cut the heads off, and thread them into the munged/stripped inserts with some redloctite. Once the loctite sets you should be able to use the inserts that are there along with some washers and nuts to support the plate nearer the rear binding.

Obviously you would be using 5 inserts instead of three like you are.

A third choice would be a product like the reflex bondplates

http://www.reflexworld.com/2010SITE/web/images/shop/12carbonds2000.jpg

where you would utilize these over the factory inserts. Which is a similar concept to cementing a threaded stud into your skis stripped holes.

Any closed cell foam should work well in that application.

http://www.northshoreinc.com/store/pc/viewPrd.asp?idproduct=190

This would be a good option, you can get it "peel and stick" or straight up.

I like to put a secondary flap of velcro that goes back over the loose end the other direction.

So factory strap comes across and lays flat, secondary closure comes across from the other side and lays across the factory strap.

That or you can usually rivet a snap through the velcro at approximately the point where you always tension the brace, pull the strap, taught and put the snap it. Velcro only likes pulling in tension.