Choosing The Right Screw Size For Your Dynastar Skis

When it comes to selecting the right screw size for your Dynastar PX 12 ski bindings, it's important to pay close attention to the screw length. Ski touring bindings often require different screw lengths for the toe and heel units, so mixing up the screws can lead to issues with binding pull-outs. To avoid this, it's crucial to evaluate all screw lengths before beginning the mounting process and to maintain a well-organised workbench to prevent grabbing the wrong screws. While the standard protrusion for a ski binding screw is about 7 millimetres, it's always recommended to measure the thickness of your skis and compare it to the screws. Thinner skis may require shorter screws to prevent damage.

Binding mount screw length

The correct binding mount screw length is critical to the safety of skiers. It is important to note that many ski touring bindings use different length screws for the toe and heel units, and using the wrong screws can lead to the binding popping off the ski. Therefore, it is crucial to evaluate all screw lengths before beginning a mount.

The normal protrusion of a ski binding screw is about 7 millimeters. However, it is important to always measure the thickness of the ski and compare it to the screws, as some thinner skis require shorter screws. Using screws that are too long can damage the ski, causing a "pimple" or blowing the layers apart.

When measuring the ski thickness in the binding mount areas, ensure that the screw length allows for a couple of millimeters of material. For very thin skis, at a minimum, the screw length should allow for a couple of millimeters of material. Shortening screws can be done, but it must be done correctly by first grinding them down and then slightly sharpening the end to ease the screw thread's insertion into the hole.

Modern skis often provide information about the size of the hole to drill, which can be done using dedicated ski mounting drill bits. For example, a 3.6 mm diameter hole that is 9.5 mm deep is commonly used, and most ski drill bits are 7.5 mm in length. It is worth noting that the Blizzard drilling information calls for a wider 4.1 mm diameter hole.

Normal ski binding screw protrusion

The normal protrusion of a ski binding screw is about 7 millimetres. However, it's important to always measure the thickness of the ski and compare it to the screws, as some thinner skis require shorter screws.

Using screws that are too long can damage the ski if the screw presses against the base laminations, causing a "pimple" or blowing the layers apart. Therefore, it's crucial to select the appropriate screw length for the specific binding and ski combination.

Modern skis often include information about the size of the hole to drill. In this case, a 3.6 mm diameter hole that's 9.5 mm deep is specified, and dedicated ski mounting drill bits are available in this size. However, it's worth noting that the minimum depth for a screw to be effective is 6mm/1/4″.

When measuring the ski thickness, it's important to focus on the binding mount areas. A 7 mm screw insertion typically allows for 4.5 mm of ski base layers, which is sufficient. Nevertheless, it is recommended to ensure that the screw length allows for a couple of millimetres of material, especially in the case of very thin skis.

Shortening screws can be done by first grinding them to the appropriate length and then slightly sharpening the end. This allows the screw threads to 'lead' it into the hole without requiring excessive downward force during the screwing process.

Ski thickness and screw length

The normal protrusion of a ski binding screw is about 7 millimeters. However, it is crucial to measure the thickness of the ski and compare it to the screw length. Some thinner skis may require shorter screws. Using screws that are too long can damage the ski, causing a "pimple" or blowing the layers apart. Therefore, it is recommended to err on the side of longer screws rather than shorter ones, as long as they do not exceed the thickness of the ski.

Modern skis often provide information about the recommended drill size and depth, which can be used to determine the appropriate screw length. The general rule for alpine ski drill bit sizes is 3.5mm for non-metal skis and 4.1mm for metal skis. However, there may be exceptions, such as metal binding plates in non-metal skis or carbon fiber top sheets. The minimum depth for a screw for a binding mount is 6mm, and the typical hole drilling depths range from 7.5 to 9.5mm.

When measuring for binding screws, it is important to consider the type of screw head, such as flathead, pan head, button, or socket. Flathead screws are measured from tip to top, while pan heads, buttons, and sockets are measured from tip to the bottom of the head. It is also recommended to tap the holes, especially for metal and carbon top sheets, to ensure a secure fit.

Additionally, it is worth noting that ski touring bindings often use different screw lengths for the toe and heel units, so it is important to keep the screws organized and evaluate all screw lengths before beginning the mounting process.

Using screws that are too long

If you're using machine screws, it's important to not damage the threads when cutting them down to size, or they won't screw in. Wood screws are easier to cut down as you don't have to worry about damaging the threads.

To cut down machine screws, you can use a pair of multi-purpose wire strippers. If the screw is too large for the wire strippers, you can use a hacksaw, jigsaw, or reciprocating saw with a metal-cutting blade. When using a saw, it's important to cut the screw as straight as possible. You can also use bolt cutters, but they can be difficult to use in tight spaces and might not give you a clean cut.

For wood screws, a heavy-duty pair of pliers or wire cutters should do the trick. Simply cut the end of the screw to the desired length. Be aware that the screw might go flying when you cut it, so take the necessary precautions.

Dedicated ski drill bits

For adult alpine skis without metal, the recommended bit size is 3.6 x 9mm or 9.5mm. For adult alpine skis with a metal or titanal mounting plate, a larger 4.1 x 9mm or 9.5mm bit is needed. Junior alpine skis, on the other hand, typically require a smaller 3.5 x 7mm bit. It is important to always follow the manufacturer's recommendations for the specific ski and binding combination.

When using dedicated ski drill bits, it is crucial to evaluate all screw lengths before starting the mounting process. Ski touring bindings often require different screw lengths for the toe and heel units, so mixing up the screws can lead to an insecure binding. Additionally, it is important to measure the ski thickness in the binding mount areas and compare it to the screw lengths to ensure a proper fit.

Frequently asked questions