A little fact you may not have known: Before Matt and Jerica became farmers, we were engineers. It’s a good thing, because sometimes there are problems here on the farm where classes like Statics and Physics really come in handy.

For example, we recently bought a larger cattle trailer that was “homemade,” not uncommon in East Texas. It’s very nice, and we like it, but on one of our first trips to the processor with a large load of cows in the new trailer, it had a blow-out so bad that it completely destroyed the hub on that side of that axle. Thankfully things turned out fine (we always plan for at least one blow-out), but we’ve had to replace everything on that axle and have been analyzing why it happened (so it doesn’t happen again!).

Matt believes it is because when the fully-loaded trailer is attached to his truck, the hitch is so tall that it forces most of the weight onto the back axle due to the trailer not riding at level. It’s too tall for a simple solution like a drop hitch, so he drew up a free-body diagram to determine how much height to cut off of the hitch.

All he needs to do now is measure the exact internal length of the trailer, then from the halfway point, measure how far back the middle axle is. Then, based on the sum of the moments around the center of gravity (assuming the cattle are evenly distributed, which is pretty reasonable) he can calculate the force that would be on his truck when the trailer is fully-loaded. He’ll take that force (in the form of lots of bags of concrete), load the back of the truck, and measure how high the ball is from the ground. He can then alter the hitch so it is a better fit to the height of the truck.

Isn’t engineering easy? Well, it’s fun, anyway.