Final answer:
The modern guideline for securing loads with tie-downs recommends spacing them 8 diameters side-to-side and 15 diameters deep for improved load stability. Older methods used different measurements and additional materials such as steel nails and rocks for securing in specific conditions.
Step-by-step explanation:
The rough guide for spacing tie-downs when securing a load has evolved from older practices. Historically, the rule of thumb was to space tie-downs 5 diameters apart side-to-side and 7-8 diameters deep. However, more recent studies suggest that a more effective configuration is spacing tie-downs as much as 8 diameters side-to-side and 15 diameters deep. This new guidance is designed to enhance the stability and security of the load.
For example, using a heavy rope, you can visualize the concept of tie-down spacing. If two people hold the rope stretched out and one end is flicked, the wave created will show the importance of proper spacing to mitigate the movement of the load.
In some scenarios, like soft rock areas, traditional methods involve using steel nails with rubber washers applied on reinforced eyelets to secure covers, in addition to placing heavy objects like rocks to help secure the covers further. This is a part of a simplified yet efficient process in comparison to earlier, more complex methods for covering and securing loads.