I use to X mine but now I don't but they are still angled out away from the axle to the trailer tie down point. The main reason for the change was the addition of new tie down anchors I added to the trailer in better locations and the chaffing or the straps at the X point. I would caution people to be aware of the angle that you are putting you straps at due to the effect that it has on the restraint it will provide in a given direction.
Generally speaking, with a strap at an angle to the longitudinal axis of the rig (front to rear), there are three mutually perpendicular components of force that all make up the resultant force vector that is the strap rating from one end of the strap to the other. This is important to think about when looking at how your straps are on there and the amount of restraint they are going to apply in a given direction. Through resolution of forces you can determine each individual component force i.e. how much is it going to hold back in a forward collision before the strap breaks and sends the jeep forward into the back of my head.
A lot of us use the 2 inch wide ratchet straps that are rated at a breaking strength of 10K. If you look up restraint of loads in military aircraft, they recommend 30 degrees from the longitudinal axis (so 30 degrees out from your axle attachment to the point on the trailer) and 30 degrees horizontal (so from the trailer deck up to the axle attachment point a 30 degree angle, not much you can do here, small tire I guess you better get bigger tires if you need more of an angle down to the trailer). Lets think about the rear straps but the same will apply to the front (just substitute forces resulting from deceleration to forces from acceleration, I think we are all concerned with the decel and lateral the most through). Ok so that means that 10 K rated strap is now providing a restraint of 7,490 lbs of restraint from the rig on the trailer moving forward in on the longitudinal axis (towards your head....eeek), 4,330 lbs of lateral restraint for when you make those aggressive lane swerves or pull a BigPrince curb jump //LMAO//, and 5,000 lbs of vertical component restraint which could come into play if the trailer rolls. Skipping over the dynamic forces acting on the trailer load during an accident or evasive maneuver, this means that if you slam on the brakes your 10 K rated strap now is providing 74.9 percent of that capacity in keeping your rig from moving forward into your head. If your strap was straight forward to back it could provide more restraint but it would lack the lateral restraint component that the two equally opposing angled straps would be providing. So swerving could result in some undesirable shifting on the trailer. The more you angle those straps either out wide to each side or the angle provided by crossing them the lower the amount of restraint before reaching the breaking limit is going to be.
Topic: Securing your Rig on a trailer discussion (Read 2945 times)
