How far away from the mast should the guy anchors be placed?
- We recommend that distance be equal to the height of your mounting point on the tower, but no less than 2/3 of it. However, sometimes this is not possible - in this case, a rope with lower absolute elongation and higher strength must be used. At the same time, it is necessary to assess whether the mast used is strong and stiff enough to handle the higher vertical load. We recommend using our calculator Forces in guy ropes to calculate the effect of the anchoring distance on the applied forces.
What a rope and how long do I need for ...?
- We offer a free calculation service of ropes strength and length needed for your project. Apart from that, we have online calculators on our web pages which you can use for calculation yourself. These tools are also available in form of an Android application – look for “Mastrant” on the Google Play store. For basic orientation, we have prepared typical installations and recommended ropes: Typical installations
What is recommended minimum bend radius of 5mm Mastrant-M and -P? Like if the rope is tied to a chain link coupler? Also, minimum pulley diameter?
- Generally, we recommend a minimum bending radius the same as the radius of the rope. You can work with knots and the breaking strength still remains approximately double that of Work Load Limit (safe working load). Of course, you can use ropes with an even smaller diameter (not sharp!) but their breaking strength decreases. Regarding pulleys, you are limited by the size of the groove in the sheave. All sheaves for particular rope have a large enough diameter for Mastrant ropes.
I have a Rohn tower and I want to use Mastrant ropes to guy it – which ropes should I use?
- Refer to: Guying ROHN Towers with MASTRANT Ropes.
I want to replace steel ropes with synthetic ones – which ropes should I use for replacement?
- Refer to Steel rope replacement.
What does elongation (stretch) percentage mean?
- The elongation in our datasheets is a relative change of the length measured between “pre-tension” (10% of breaking strength) and “working tension” (30% of breaking strength).
I have dipoles rigged at about 42 m between much taller trees. These trees move a lot in the wind, so support ropes go through pulleys at each tree, tied down on one end and with a 100 lb weight on the other, but pull forces can be significantly greater when the wind is blowing and the rope moves back and forth a lot. Are any of your ropes suitable for this use?
- We suggest for this purpose Mastrant-Q 1/4" (6 mm) or Mastrant-P 3/16" (5 mm). Plus quality pulley with a larger sheave diameter and preferably with a needle (ball) bearing (for example, this one). You can also consider a system using elastic ropes designed for outdoor use.
I am guying a vertical and was only able to buy the 2mm Mastrant-P (larger sizes sold out). My intention is to use a double length on each guy folded back to the common fixing point. As I now have two lengths running in parallel with a strength equivalent to 4mm rope. 1) Will the rope still have the same percentage stretch or is it increased?2) As I will be running 2 in parallel, is it advisable to leave them running side by side or with a small twist?
If you use two 2mm ropes in parallel, you WILL NOT get the strength of 4 mm rope (440 daN). You will theoretically get a strength two times the strength of 2 mm rope, which is 2x 100 daN. Practically the strength will be slightly lower because you will never get the optimal spread of tensions like in the single rope.
Regarding your questions:
1) The percentage stretch will not change - it remains the same because the material and construction of the ropes remain the same. You will get a lower absolute stretch. This means that if you load the rope with a force of, for example, 30 daN, it will lengthen approximately half as much as if you use a single rope.
2) It does not matter at all. Choose what is more practical for you.