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Should You Buy Rotary Forged?

Fitment Industries Author | | August 22nd, 2018 |

  • - Hey guys what's going on it's Ash from Fitment Industries and you might be wondering "What is Rotary Forged?" and who is Rotary Forged, but most importantly why is rotary forged?
    - Why is Gamora?
    - You guys have been dropping comments asking us to talk about it, so we figured that's exactly what we would do today on a Thursday evening, so let's just get right in to it. It's a fancy term right? So much so that there's been well couple different companies that have actually tried to copyright and trademark terminology itself. Rotary forged has had a lot of history in to what it does and why it's becoming so popular especially in today's day and age. First off let's take it back to just traditional casting ever since wheels have been a thing. Casting has had a lot of different adjustments and evolutions to make the metal less porous, and to essentially make wheels stronger over time. You've had basic sand casting. You've had traditional gravity casting, low pressured casting, endurval die casting, and a bunch of other different ways. People have made their wheels to try and improve it, either making it more cost effective, making it a better wheel, or just deciding to try something different to see if it would work. And you've had companies like Enkei that have gone way off in doing their own specific casting treatment, that they really don't want to tell others how they do it. And now its kind of jumped into the rotary forged game as well. So, if you were unfamiliar with what rotary forging is, what that essentially is in the basic terminology of it all, is that when you're making a wheel you have a mold. And then the metal will get poured into the mold, or it get injected into the mold, and that's the difference between gravity casting and low pressured casting as just a fundamental terminology. What ends up happening is that at the rim of the wheel you have a big chunk of metal that's left behind. Usually in normal casting methods when you're pressure casting the injection mold will go all the way through the rim, and then it uses pressure to help maintain the molecular structure of the metal. Cools it off you're ready to roll. In gravity cast it's usually just a mold that the metal will float into until its filled that entire empty space which is essentially the wheel. And then it's cooled off, treated, and all that sort of good stuff. So what happens with rotary forging is you're left with the face that is still cast, but then a good chunk of metal is left around the outer rim. What happens is they take that, they put that on another machine, and they spin it at a high rate of speed. As well as the metal being already at an extremely high temperature, there are two rollers or usually more than that will then attach to that machine and roll out the metal. Really with a rotary forged wheel it has a cast face with the barrel itself being the same techniques and properties of a forged wheel. So there is two million reasons for rotary forged wheels. The first reason is obviously to save weight. Now if you're looking at a cast wheel with a cast barrel, a lot of those 20x11s can weigh a pretty good amount. You're looking at around 35, sometimes even more than that pounds per wheel, and if you put that on each corner, that's a lot of weight. So what rotary forging does is it eliminates that, by just essentially creating a more streamline approach with using less metal that is less porous, cause it has less air pockets, and overall you just get a lighter wheel. The second most important thing for rotary forging is that it increases the molecular grain structure of your barrel. Now with cast wheels the metal is kind of all over the place and the elements inside of that alloy can sometimes leave air pockets, it can leave imperfections, at the molecular level.

    What happens with rotary forging is because of the rollers are spinning at a high rate of speed, it's treating the metal very similar to as you would a dough, and you can align that dough the way that you want to. And when you align it correctly, which is what the rotary forging machine does, it increases the strength of the metal by just essentially putting it, layer on top of layer, very similar to carbon fiber. Where as when you're looking at a low pressured cast, or even gravity cast, it's still kind of tossed and hodgepodged in there, and it's not gonna have the same effects as a clean rotary forged wheel. Rotary forging is just a very simple way to increase the molecular grain structure of a wheel, without necessarily adding a huge cost, like having a forged wheel. When you have a forged wheel you have a lot of the same properties of rotary forged, except the face of the wheel is also gonna have the same almost molecular structure, as the barrel of a rotary forged wheel. But there's a lot of things that goes into rotary forging much above just the technique itself. Because not all rotary forging is created equal. We've seen a lot of companies come out with rotary forging techniques, and spin forged, and flow form, and compression forged, and everything in between to put their own name on essentially the same technique. But every technique can be a little bit different, and if you're not looking carefully, you can run into a little bit of marketing skews, that aren't necessarily true, but you're not gonna be the wiser unless you have somebody on the inside telling you about some things to keep an eye out for if you're looking to buy rotary forged wheels. The first thing that you have to remember with rotary forged wheels is that there's gonna be a lot of different names. And while there are varying techniques on how to get a rotary forged wheel, they are almost all essentially very similar techniques. You're not gonna to see a lot of companies that are gonna stray away from that style, because most manufacturing plants overseas use almost the same exact machines, as well as everybody else. There's very few machines that are going to deviate from that process, because it's a very well automated process that a lot of people don't have to worry about in terms of overhead. The second thing you have to consider with rotary forged wheels is that, it does not have to be a certain length of rotary forged on the barrel for it to be deemed, "rotary forged." Because there's not a whole lot of regulation behind the term of rotary forged, and what it means, and the requirements for you to deem it a rotary forged wheel.

    You can run into certain companies that will sometimes offer "rotary forged" wheels that aren't, well, that much lighter than their standard cast wheel. And the reason for that is because a lot of the times there will be companies that will not rotary forge out an entire barrel. They'll only do maybe 50%, or even less if they have to, because it's gonna save them money in the long run. And what you're gonna happen with that, is that you're not gonna get the necessary properties of what makes a rotary forged wheel so awesome, in your wheel. Some of the most iconic rotary forged wheels right now are obviously the TSW's, they coined it, they use it a lot, in almost all of their wheels. Another great example is Rohana. Rohana's rotary forged wheel lineup on their RFX series is absolutely stellar. Konig is another one shortly behind. And you're gonna have a lot of companies that are gonna be able to get the tech, whether they have a partner company, or parent company that has a lot of money behind them. But just be careful that you're looking at the wheel weight of rotary forging, because if you notice that there's not a very big difference between the two, you might find out that rotary forging is really only a very small section of the barrel of your traditional cast wheel, and you're not gonna get the same benefits as you would from a reputable company that's been in it for a long time. The current scene is going to larger wheels with wider widths. You're gonna see a lot of people going into the 19x10s, 19x11s, 20x10s, 20x11s. There's very few people that are actually purchasing smaller wheels now, versus the early 2000s even into the 90s. It seems like the sport, compact size of wheels is kind of going away. And as as result you have a lot of these companies offer bigger, wider wheels to fit the wheel wells more appropriately for other cars.

    The problem with that is that when it goes back to wheel weight, if you're looking for a big wheel, it's gonna be extremely heavy. Buying rotary forged allows you get a nice wheel without necessarily having to sacrifice drivability, brake responsiveness, acceleration, or pretty much any sort of performance aspect, because rotary forging is almost always gonna be a better option than your cast counter part. You'd be surprised not to see rotary forged wheels become more popular in the next two to three years, because of the technology that they provide, and the fact that they're not super expensive. So if you're looking to pick up a set of rotary forged, or if you have questions, check out Fitmentindustries.com, or just drop a comment below. We'd be happy to answer you guys. Don't forget to check it out. Wheels, tires, suspension, all that good stuff, and of course don't forget to subscribe. But I'm Alex from Fitment Industries, let us know what you'd like to talk about next week. Peace.