The Rotti NNN-BC Binding Conversation
Posted: Sun Mar 10, 2024 2:08 pm
I was entertained and intrigued by the amount of different opinions on the Rottefella NNN-BC binding options.
The current 3 options would be the Automatic, the Manual and the Magnum.
Some opinions/views are based on visuals, some on physics, some on engineering, some on a personal belief backed by certainty or guesstimates but not necessarily conclusions by any particular science or engineering tests
And some based on just plain old how they felt out on the snow.
The best of the best was the topic of the "Manuals" VS the "Magnums" as for the differences and how that effects the ability to roll the ski.
Presently, I don't have a pair of Automatics on hand for my observations but the differences are more obvious as compared to the manual locks mechanisms and others have well covered the freeze up differences from their own experiences. As to trouble getting the Automatics off if you fall through the ice, all I can say is I hope no one experiences that test first hand. Pretty sure any of the three variations are going to be tricky to get off in jiffy once you realize what just happened to you and your heart starts to hit adrenaline mode trying to delay the shut down mode if you don't get out of the icy water.
So with out further ado here are my conclusions...
Weight in grams per pair with/without screws:
Older 89 timeline Manuals with/without screws 411/382
Current Manuals with/without screws 469/439
Current Magnums with/without screws 527/497
Weight in grams each without screws:
Older 89 timeline Manuals without screws 191
Current Manuals without screws 219.5
Current Magnums without screws 248.5
Width at widest point of binding plastic overall:
Older 89 timeline Manuals 50mm
Current Manuals 57mm
Current Magnums 67mm
Width of Binding Base that contacts ski near boot pin lock/underfoot
Older 89 timeline Manuals 50mm/50mm
Current Manuals 52mm/44mm
Current Magnums 55mm/55mm
Lock mechanism strength between the 3 appear to been equal
Ability to unlock in order from easiest to hardness Magnum/Manual/89 Manual
Ability in theory to be able to put force to turn or roll the ski from most to least
Magnum/Manual/89 Manual
This analysis was based on the overall binding width contacting the boot sole, the overall binding width plastic actually contacting the ski, the width of the ski and a bit of magic dust thrown in.
Although the Magnum is 10mm wider than the Manual overall width the difference in actual binding base plastic contacting the ski is 3mm difference near the boot lock pin point and 11mm difference underfoot. 44mm of the contact point underfoot is the same extrusion width on both Magnum and the Manual. The difference is the Magnums first level of plastic web reinforcement widens out to 55mm to match the contact area near the lock pin. The second level of web reinforcement that extends out to the overall 67mm width of Magnum tapers upwards and doesn't contact the ski but the full 67mm width of the Magnum does contact the the boot sole on the top side of the binding. The Manual has 57mm of binding contacting the boot sole and the old 89 Manual has only 50mm contacting the boot sole.
In order to use the maximum potential from of the extra base area of the Magnum's 55mm binding to ski contact width and 67mm boot sole to binding contact area, in terms of force to roll ski, you would be best to put it on a ski that is 55mm or greater at the waist. And alternatively in order to gain the most force on the ski to roll the ski the Manuals should be installed on a ski that is at least 50-52mm or greater at the waist. This allows for the most binding to ski contact area for the different width bindings.
Putting a Magnum on a ski narrower than 55mm at the waist, lets say at the 52mm recommended minimum, will not be a fully efficient use of the extra base contact area of the Magnum over the Manual. Yes the ability to transfer force to roll the ski still is present on the base plastic that is protruding over the edge of the ski mounting surface but in that scenario the plastic has more ability to flex under force and as well possibly could put more pull out force on the binding screws by means of cantilevered force over a pivot point. To understand that cantilevered force over a pivot point think of a using a crowbar or a 2x4 as a lever to lift an object up. You can exert the same amount of force on the lever end of the crow bar or 2x4 but the longer the pry bar or 2x4 is is and the farther out from the leverage pivot point you are you will exert more force to lift the object.
For the same reasons of extra binding to ski contact area of the Magnum vs the Manual there will be more leverage force ability out from the ski center point using a Magnum vs a Manual on a ski wider than 52mm-55mm. As for the boot sole itself contacting the ski top surface to apply force that is not going to happen unless you brake the lock pin connection or the binding releases. In that case you are likely going to eat some snow when that happens.
Now the minimum ski width recommendations for the Magnum Vs the Manual even from Rottefella can get a little murky as the ski width dimensions are taken at the base side of the ski and not the top binding contact side. Older XCD skis were more square sides with the tops widths similar to the base widths at the waist but the newer BC skis have quite a bit of an angle to the sides so consequently the top binding mounting surface is narrower in width than the base width.
As an example the 54mm waist on the base side of the Asnes Gamme and the E99 is only 44/45mm on the actual top mounting surface of the skis. So I doubt whether a Magnum on those skis 44/45mm mounting widths is tremendously more beneficial than the Manual unless you are an aggressive skier and you have made sure your screws are not loose; literally
As well the newer XDC/BC skis are lighter and have less depth at the binding mount point with less screw bite than than the older skis. Your bite is around 9-9.5mm on the newer NNN-BC binding fasteners but the older XCD/BC skis the bite could be up to 12-15mm. Make note that the 15.5mm long and 3.6mm wide drill stated in the Rottefella install instructions is for using with the Rottefella drill template only. For non template drilling use a 3.6mm (9/64") drill with a drilling depth of no more than 9.5mm deep.
The Magnum is the heaviest of the three versions, it has the most plastic and design rigidity across its overall width, the most binding to ski contact area, the most boot sole to binding contact area, the widest lock lever and widest front end plastics. It should be a stronger binding overall based on amount of plastic extrusion materials, and the web reinforcements of the Magnum's wider width along with its wider binding to ski contact area may even exert less screw pull out force providing the full width of the Magnum bade is contacting the ski.
Claims from Rottefella state the Magnum features an extra wide 67 mm contoured and reinforced binding steering plate designed to increase the contact area between boot sole and binding plate. They claim this wider 67mm binding to boot contact area will greatly improve stability and deliver more turning power to ski edges. There would appear to be merit to those claims.
In conclusion they are all capable bindings with the Magnum having an edge over the Manual on a wider ski just purely by physics, engineering design and mass of materials. The Magnums are better suited for wider skis but can be used on skis 52mm and greater. The Magnums on 52mm wide at the waist skis may be the best option if you are planning any 360 total body side rolls
How much of an edge that translates to may be better found out on the snow in various conditions and in the end it might just be feeling or preference rather than the science. I assume aggressive skiers can really make use of the Magnum on low end of the 52mm recommended ski width but make sure your screws are tight on the Magnum to narrow ski installs.
This current lack of snow has taken getting out on the snow out of the picture but on the flip side I made a template for mounting the NNN-BC bindings on multiple skis. One is for regular fasteners and 9/64" drill size and the other is for installing inserts into skis and using stainless steel chamfered head bolts. With the cost of the NNN-BC bindings at over $100 a pop regular price it may be worthwhile on some beefier and maybe less used older skis to insert them and share a binding between skis using Vibra-Tite VC-3 Threadmate threadlocker.
I hope this info may be helpful or at least interesting to some.
The current 3 options would be the Automatic, the Manual and the Magnum.
Some opinions/views are based on visuals, some on physics, some on engineering, some on a personal belief backed by certainty or guesstimates but not necessarily conclusions by any particular science or engineering tests
And some based on just plain old how they felt out on the snow.
The best of the best was the topic of the "Manuals" VS the "Magnums" as for the differences and how that effects the ability to roll the ski.
Presently, I don't have a pair of Automatics on hand for my observations but the differences are more obvious as compared to the manual locks mechanisms and others have well covered the freeze up differences from their own experiences. As to trouble getting the Automatics off if you fall through the ice, all I can say is I hope no one experiences that test first hand. Pretty sure any of the three variations are going to be tricky to get off in jiffy once you realize what just happened to you and your heart starts to hit adrenaline mode trying to delay the shut down mode if you don't get out of the icy water.
So with out further ado here are my conclusions...
Weight in grams per pair with/without screws:
Older 89 timeline Manuals with/without screws 411/382
Current Manuals with/without screws 469/439
Current Magnums with/without screws 527/497
Weight in grams each without screws:
Older 89 timeline Manuals without screws 191
Current Manuals without screws 219.5
Current Magnums without screws 248.5
Width at widest point of binding plastic overall:
Older 89 timeline Manuals 50mm
Current Manuals 57mm
Current Magnums 67mm
- Three Amigos Top & Bottom views
Width of Binding Base that contacts ski near boot pin lock/underfoot
Older 89 timeline Manuals 50mm/50mm
Current Manuals 52mm/44mm
Current Magnums 55mm/55mm
- Binding to ski contact near Boot pin lock
- 3 BC Amigos binding bottom to boot sole
Lock mechanism strength between the 3 appear to been equal
Ability to unlock in order from easiest to hardness Magnum/Manual/89 Manual
Ability in theory to be able to put force to turn or roll the ski from most to least
Magnum/Manual/89 Manual
This analysis was based on the overall binding width contacting the boot sole, the overall binding width plastic actually contacting the ski, the width of the ski and a bit of magic dust thrown in.
Although the Magnum is 10mm wider than the Manual overall width the difference in actual binding base plastic contacting the ski is 3mm difference near the boot lock pin point and 11mm difference underfoot. 44mm of the contact point underfoot is the same extrusion width on both Magnum and the Manual. The difference is the Magnums first level of plastic web reinforcement widens out to 55mm to match the contact area near the lock pin. The second level of web reinforcement that extends out to the overall 67mm width of Magnum tapers upwards and doesn't contact the ski but the full 67mm width of the Magnum does contact the the boot sole on the top side of the binding. The Manual has 57mm of binding contacting the boot sole and the old 89 Manual has only 50mm contacting the boot sole.
- Magnum base contact with the ski
In order to use the maximum potential from of the extra base area of the Magnum's 55mm binding to ski contact width and 67mm boot sole to binding contact area, in terms of force to roll ski, you would be best to put it on a ski that is 55mm or greater at the waist. And alternatively in order to gain the most force on the ski to roll the ski the Manuals should be installed on a ski that is at least 50-52mm or greater at the waist. This allows for the most binding to ski contact area for the different width bindings.
- Magnum side boot sole to binding
- Manual side boot sole to binding
- Old Manual side boot sole to binding
Putting a Magnum on a ski narrower than 55mm at the waist, lets say at the 52mm recommended minimum, will not be a fully efficient use of the extra base contact area of the Magnum over the Manual. Yes the ability to transfer force to roll the ski still is present on the base plastic that is protruding over the edge of the ski mounting surface but in that scenario the plastic has more ability to flex under force and as well possibly could put more pull out force on the binding screws by means of cantilevered force over a pivot point. To understand that cantilevered force over a pivot point think of a using a crowbar or a 2x4 as a lever to lift an object up. You can exert the same amount of force on the lever end of the crow bar or 2x4 but the longer the pry bar or 2x4 is is and the farther out from the leverage pivot point you are you will exert more force to lift the object.
For the same reasons of extra binding to ski contact area of the Magnum vs the Manual there will be more leverage force ability out from the ski center point using a Magnum vs a Manual on a ski wider than 52mm-55mm. As for the boot sole itself contacting the ski top surface to apply force that is not going to happen unless you brake the lock pin connection or the binding releases. In that case you are likely going to eat some snow when that happens.
Now the minimum ski width recommendations for the Magnum Vs the Manual even from Rottefella can get a little murky as the ski width dimensions are taken at the base side of the ski and not the top binding contact side. Older XCD skis were more square sides with the tops widths similar to the base widths at the waist but the newer BC skis have quite a bit of an angle to the sides so consequently the top binding mounting surface is narrower in width than the base width.
As an example the 54mm waist on the base side of the Asnes Gamme and the E99 is only 44/45mm on the actual top mounting surface of the skis. So I doubt whether a Magnum on those skis 44/45mm mounting widths is tremendously more beneficial than the Manual unless you are an aggressive skier and you have made sure your screws are not loose; literally
- Mag/Man/Old Man on Rossi BC65 ski with 52mm waist
As well the newer XDC/BC skis are lighter and have less depth at the binding mount point with less screw bite than than the older skis. Your bite is around 9-9.5mm on the newer NNN-BC binding fasteners but the older XCD/BC skis the bite could be up to 12-15mm. Make note that the 15.5mm long and 3.6mm wide drill stated in the Rottefella install instructions is for using with the Rottefella drill template only. For non template drilling use a 3.6mm (9/64") drill with a drilling depth of no more than 9.5mm deep.
The Magnum is the heaviest of the three versions, it has the most plastic and design rigidity across its overall width, the most binding to ski contact area, the most boot sole to binding contact area, the widest lock lever and widest front end plastics. It should be a stronger binding overall based on amount of plastic extrusion materials, and the web reinforcements of the Magnum's wider width along with its wider binding to ski contact area may even exert less screw pull out force providing the full width of the Magnum bade is contacting the ski.
Claims from Rottefella state the Magnum features an extra wide 67 mm contoured and reinforced binding steering plate designed to increase the contact area between boot sole and binding plate. They claim this wider 67mm binding to boot contact area will greatly improve stability and deliver more turning power to ski edges. There would appear to be merit to those claims.
In conclusion they are all capable bindings with the Magnum having an edge over the Manual on a wider ski just purely by physics, engineering design and mass of materials. The Magnums are better suited for wider skis but can be used on skis 52mm and greater. The Magnums on 52mm wide at the waist skis may be the best option if you are planning any 360 total body side rolls
How much of an edge that translates to may be better found out on the snow in various conditions and in the end it might just be feeling or preference rather than the science. I assume aggressive skiers can really make use of the Magnum on low end of the 52mm recommended ski width but make sure your screws are tight on the Magnum to narrow ski installs.
This current lack of snow has taken getting out on the snow out of the picture but on the flip side I made a template for mounting the NNN-BC bindings on multiple skis. One is for regular fasteners and 9/64" drill size and the other is for installing inserts into skis and using stainless steel chamfered head bolts. With the cost of the NNN-BC bindings at over $100 a pop regular price it may be worthwhile on some beefier and maybe less used older skis to insert them and share a binding between skis using Vibra-Tite VC-3 Threadmate threadlocker.
- DIY Drill jig for multiple installs
I hope this info may be helpful or at least interesting to some.
