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R3 - Joint?

R3 - Joint stands for Rope-Reinforced-Rubber-Joint and, put simply, means that the safety line runs in the core of the rubber joint. Should the rubber joint ever bless its time, the board and sail remain securely connected via the built-in aramid tendon (Kevlar) with a breaking load of approx. 200 kg. Due to the internal guidance of the tendon, this also prevents overstretching of the rubber joint, for example if you cling to the mast of the sail during a wash in the waves. Another advantage is that due to the very short excess length of the tendon of only 5-10 mm compared to the rubber joint there is only comparatively little play. In the event of a break, the function of the joint is better preserved, which increases controllability in contrast to external safety lines.



The R3 - Joint joins the existing standard of rubber joints. The rough dimensions are 42mm in diameter and approx. 58mm high and thus correspond to the dimensions of existing "Boge" rubber joints.

Thread Options:
M10 / M8
The M10 / 8 thread option means that the rubber joint is equipped with an M10 thread and an M8 thread on the opposite side. The M10 / M8 version is usually used with so-called 1-bolt mast base systems. The S4LT 211 Base works technically differently than the systems of the competition, but also uses the version with M10 / M8 thread. A one-piece M10 Europin is provided for the M10 thread. The M8 thread is used to hold an M8 grub screw. To secure against unscrewing, both the Europin and the grub screw are permanently glued with, for example, green Loctite or comparable products.

M10 / M10 (in planning):
The thread option M10 / M10 means that the rubber joint is equipped with M10 threads on both sides. This option is usually used for so-called 2-bolt mast base systems. This means that a mast base plate is screwed to the mast rail using 2 bolts/screws. The mast base plate usually has a mount for the elaborately designed socket of the rubber joint, which is connected to the rubber joint with an M10 screw.


Special feature:
The 211 Base is unique in its patented construction. The connection between the mast foot plate and the rubber joint is made using a screw connection, for which the R3 joint was specially designed. This means that only R3 joints can be used for the 211 base. The other way around, however, the R3 joint joint is compatible with other mast foot systems with rubber joints from other manufacturers.


Rubber joint equals Tendon?
Please note that a so-called tendon joint cannot be compared to a rubber joint. These are different systems with different advantages and disadvantages! First of all, a tendon joint cannot be used for a mast foot system with a rubber joint. Conversely, this works just as little!

Tendon vs rubber joint:
Mast base systems with tendon joints are superior to conventional mast base systems with rubber joints in terms of their overall height. This means that the construction height of the mast base is up to 20 mm lower.

This means that the fork can be mounted 20 mm lower with the same performance. In other words, it means that the surfer can raise the boom 20 mm with the same height setting for him, which shortens the overhanging length of the mast beyond the boom. The flex in the mast above the boom is therefore reduced, which increases sailing performance. 

Another advantage of the tendon joint is its significantly lower weight, which is due to its narrow design. However, this has the decisive disadvantage compared to the rubber joint, because the tendon joint is significantly harder with a very small contact area, which leads to undamped power transmission. In hard bump and jump conditions, a mast foot with a rubber joint should therefore always be used.

The 211 Base, on the other hand, manages the balancing act so that it combines the advantages of both systems!
see: 211 Base

Heavy-duty black anodized T6 aluminum thread mount connected by a highly flexible aramid cable with a breaking load of approx. 200 kg. Metal thread coated with PA6 (polyamide) plastic in an injection molding process. Rubber sheath made of EDPM.

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