Yes, Equal powder is the same theory. In fact, so is water, and beach sand, and golf balls and antifreeze etc.The thing with Equal powder (according to the internet) is that your air source must be completely dry. Using water can cause your steel rims to rust. Anti-freeze coolant should not cause rust (one of the reasons we run it in our vehicles) but if you are aired down and blow a bead on the trail, a fairly common occurrence, your water/antifreeze/Equal powder can and according to Murphy's law will blow/leak out. Then when you air your tire back up you have to find something to put back in the tire for the ride home. Either that or hope there is enough of whatever you used as a balancing agent left in the tire to get the job done.
The original commercial application specific dynamic balancing agent was actually mercury. Semi truck tires were not that well engineered, too large for traditional balancing machines, and used heavy (and dangerous) two piece wheels. There was an attachable ring, hollow like a hula hoop- only smaller, that fit to the outside of the wheel where traditional stationary lead weights would attach. This tube was filled with some mercury and as the wheel pickup up speed, the mercury would be slung around inside the tube, eventually settling across from the imbalances in the wheel/tire. Mercury was chosen for the balancing medium for several reasons. It didn't freeze in non extreme winter weather, it is very dense so a little bit goes a long way, it is slippery so it could easily find its way around the tube, and it caused no wear to the inside of the removable tube.
As for BB's, I have personally used both Airsoft and steel. My experience is that both work equally well. I used the airsoft BB's to balance used 31" BFG AT's on stock steel Jeep wheels. I read online that the clear Airsoft BB's turn into dust, so I used a gray, very dense, airsoft BB. It took a
LOT to equal the weight of a couple big lead wheel weights (i don't have a small scale, so thats how I approximated) I read that since the weight is further from the center of the wheel, that less weight is needed to balance the wheel/tire combo, which sounds accurate. i however just dumped in a bunch and hoped for the best, and it worked fine. I just took a
LOT of BB's to yield the weight I wanted.
I also used steel BB's to balance my current wheel/tire combo, used and chunked 33x12.50 R15 MT's on rashed 10" wide street locks (an already difficult wheel to balance because weights can only be affixed to one side of the rim) I got on Pirate(sorry
) and searched for a while. I came up with, Use steel BB's, Silver zinc coated ones because the coper will chip off of the other ones and clog your valve stems when you air down, and use one shot glass full for a 35" tire or smaller and two shot glasses full for a 36" or larger tire. (I imagine that once you get past a 40" tire though, you may want to consider adding another shot glass full, just in case.)
I was balancing 33" tires so I needed one shot glass full per tire. I bought a 4000 ct. carton of zinc coated BB's, broke the tire from the wheel, realized I do not actually own any shot glasses, evenly divided the carton of BB's into five little cups, poured one into each of four tires, divided the contents of the fifth cup in half, set on half to the side, divided the other half equally into all four tires, aired up, put my wheels back on my Jeep, test drove it, it worked perfectly, took the other half of the fifth cup of BB's that I had set aside, dug out my ole BB gun, and went plinking. Good day.
The steel BB's with the steel rims sound kind of like rain when I have my doors off, and is barely noticeable when I have my doors on (mostly because of the MT tread) and once I reach 15-20 MPH, all of the BB's have settled to the inside of the tread carcass of the tire. And they stay there until about 5 mph, where they all let go at once and come crashing down inside the tire, effectively shot-peening the inside of my wheel. I don't yet know if they are going to chip the paint on the inside of my wheels or not. Only time will tell.
