The bigger brother of the Loos & Co. Professional wire tension gauges the RT10M and RT11M are specifically designed for rod rigging and higher tensions. Easy to use, just slide the rod between the two upper rollers and then pull the spring loaded gauge onto the rod, you will be able to measure accurately rig tension for quick and repeatable tuning. Each model covers a range of approximately 5% to 25% of the breaking strength of the rod with 3% accuracy. Rig tension can be adjusted with the gauge in place.
All models are manufactured of anodized aluminium, are non-corrosive and will give years of service. Detailed operating instructions are included with each tension gauge.
Metric versions for rod.
RT-10M for rod diameters 4.4mm, 5mm, 5.7mm 6.3mm, 7.1mm
RT-11M for rod diameters 7.1mm, 8.4mm, 9.5mm
See "Attachments & Downloads" for further instructions and Imperial rod conversion labels
HOW MUCH TENSION?
There is no standard tension setting suitable for all boats, the correct tension depends on boat design, rigging type, sail design, sailing conditions and many other factors. Unfortunately many skippers use insufficient tension because of a fear of "breaking something and many boats have under tensioned rigging. We suggest you contact your boat manufacturer for advice if possible.
Forestay Tension Masthead Rig - 15% of the breaking strength of the rod is a good starting point. Since the backstay makes a greater angle to the mast, the backstay tension will be lower than the forestay tension. Backstay tension would, of course, have to be adjusted to maintain a straight mast with the desired forestay tension.
Forestay Tension Fractional Rig - At least 15% of the breaking strength of the rod is a good starting point, however, if this results in excessive mast bend it will be necessary to back off a bit. On some fractional rigs, diamond shrouds are used to reduce mast bend. A fractional rig the forestay does not go all the way to the masthead and forestay tension cannot be directly balanced by tension in the backstay. Therefore, some mast bend is generally accepted and the mainsail is cut to fit the bend.
Shrouds Masthead Rig - 10% to 12% of the breaking strength of the rod before sea trials. There is a simple method for fine tuning shroud tension. The initial rigging tension should be high enough that the leeward shrouds do not go slack when sailing close-hauled in a reasonably brisk breeze. The proper value for your boat can be found by a few trial runs under sail. Once the correct tension is known, the gauge can be used to maintain the value.
Shrouds Fractional Rig - 10% to 12% of the breaking strength of the rod before sea trials. For most fractional rigs the correct shroud tension is the same as that for a masthead rig, i.e., a tension setting that will keep the leeward shrouds from going slack. However, there is one exception. On certain fractional rigs, the upper and lower shrouds lead to chain plates that are aft of the mast. The spreader is swept back. For such a rig most of the forestay tension is balanced by the upper shrouds. A shroud tension of approximately 20 % of the rod strength may be required to achieve the desired forestay tension.
Never exceed 25% of the rod breaking strength without professional advice.
Nitronic 50 Rod
No posts found