Jumping from a previous discussion, and showing my ignorance, can someone explain the DIN settings?

I know this is the setting for your bindings and will help determine at what force the bindings will release. But, if I wanted to change my DIN settings, what rules should I go by?

If you have to ask, you probably don't want to mess with your DIN settings. Why are you thinking of changing them?

DIN settings are the value of the tension release spring in a binding. The values correspond to the amount of forced required to cause the binding to release. The higher the DIN, the greater the amount of force required to act on the spring before release occurs. Two rules apply to DIN settings.

1. Only have a trained techician with the right equipment test and adjust the DIN setting. The numerical DIN value is only a general indication of the force necessary to release the binding in an accident. Assigning DIN values requires asssessment of a number of factors including body weight and skiing style. This is only a starting point. The DIN setting is then tested to determine if it corresponds to manufacturer specifications. Adjustments are made accordingly. As springs can wear out over time, the annual release check test is vital to ensure DIN values are correctly set. Older bindings may actually require a higher setting as they age.

2. If you are tempted to adjust DIN settings on your own, see rule #1.

Jim

Age is another factor in setting the DIN.

I'm not going to readjust my settings. I'm just trying to learn more and increase my knowledge.

I too would like more information.

I am, ahem, over 50 and I rate myself, conservatively, as a lower intermediate skier. The shop set my din at 5.5 which I think is maybe a tad too high. The reason I am asking is that my sister who is an expert skier with more than 30 yrs of US and EU skiing, had a bad accident last winter. She still doesn't know exactly what happened but she went down hard and her skis didn't release, resulting in just about everything being destroyed in her left knee. She wears a brace and is looking at a minimum of 18 more months therapy etc., before she can get back on her skis. She contributes her injury to the fact that her ski didn't release when it should.
I sure as hell don't want that to happen to me! Any ideas as to how I can nicely suggest to the tuners to be conservative in my din setting? I guess knowing a bit more knowledge about the settings might be helpful.
Thanks.

Some factoids about DIN settings I've picked up over the years. Feel free to correct me if I'm wrong.

Bindings do not perform at optimum when set at a DIN setting at one of the extremes (either the upper or lower end). Since they are mechanical devices (springs et al), they perform best in the linear range which is the broad middle of the scale.

Height, weight and level of the skier (Type I, II, III) go into determining the DIN setting. You provide this info when you have your skis serviced. These affect the forces and torques on the bindings experienced during normal skiing. Not sure if the age of the skier (of an adult) really makes that much difference.

Don't put your boots on in the parking lot and walk to the lodge. You'll wear away the toe/heel contact plates at the bottom of your boot which contact the binding. Worn boots will affect binding performance. (Not sure if all boots have replaceable plates.) Plus your feet will feel a lot better at the end of the day. Ski boots are pieces of athletic equipment, not footwear.

snowcone, just because a ski didn't release doesn't mean it should have released during your sister's fall. It depends upon how the binding was "loaded" during the fall. For instance, say a skier leans too far into a turn and loses their edges as the skis skid sideways. Since little weight is being applied to the skis as the skier is falling, the binding probably won't release. The skier is in an unnatural (but maybe common) position wrt the skis, ie sliding on their hip/butt with the skis dragging on the snow. Depending upon how the skis dig into the snow, the bindings may not be torqued enough to cause a release, but the skier, being in a twisted position, may experience an injury.

Given the severity of your sister's injury, I suspect she fell backwards while one of her skis was carving. This is the most common source of major knee injury for advanced skiers and ski racers. (Short of hinged-spring systems attached to the back of skiers legs and boots, I don't think a technical solution exists.) I *thought* I read somewhere that it's more common for advanced skiers (versus intermediates) and *possibly* more common for shaped skis (since they carve easier). I'm not sure if a slight DIN change (say from 5.5 to 4.5) would make a difference for this type of fall. Either Ski or Skiing magazine ran a series of articles about this type of injury a few year's back.

Sorry to hear about your sister's fall. I must confess that all too often I put my boots on at the car. Hopefully, I'll change the habit this year.

I wouldn't worry too much about your binding settings not being conservative enough if you have honestly given a shop all the correct info. If you have some particular injury or concern, perhaps you should point that out to whoever works on your bindings. Generally shops are fairly conservative when setting bindings.

[This message has been edited by Otto (edited 08-26-2003).]

If you are really worried, you can roughly double check the shop settings by forcing an intentional release. If you can do this with only mild discomfort, you will know that in those types of falls that permit the bindings to work, you will most likely come out without injury.

Be advised, however, there are lots of pros and cons to this approach. For detailed discussions of this, take a look at:

http://www.epicski.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=2;t=004861

and

http://www.epicski.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=1;t=004221#000000

Good luck,

Tom / PM

[This message has been edited by PhysicsMan (edited 08-28-2003).]

Ouch! Sorry to hear of your sister's accident. One of the problems with modern bindings is that they will not release in all situations where it may be helpful. That's not a fault of the binding, it is simply the status of the technology. The other side of the problem scale is when a binding releases prematurely. Its not a fun feeling to be carving through the bumps or hopping a short jump only to hear "click" as one or both of your bindings release. One way to minimize knee injuries is learning how to fall. Generally, as you fall, you don't want to fight it. If you find yourself going in a backwards fall over the back of your skis, you want to try to lean over to the side to avoid loading your knees. There are articles and other information about knee injuries and avoiding them - here are a few:

http://www.ski-injury.com/prevention.htm
http://www.ski-injury.com/knee.htm
http://www.jointhealing.com/pages/sports/skiing.htm (this one has info on other injuries as well).

[This message has been edited by Jim (edited 08-27-2003).]