Street Tech Formula (STF)
Almost every wheel manufacturer claims to use the latest and greatest technology—new urethanes, invincible graphics, Robotron 3000 heliumfilled cores—many of which are mere marketing hype. With Street Tech Formula (STF), however, BONES could actually be on to something. Skateboard Trade News sits down with BONES Brand Manager Rob Washburn, and finds out.
STN: HOW DID BONES WHEELS BEGIN?
Washburn: That’s kind of a funny story. I don’t know how many people actually know this, but George and his son used to skateboard together and they skated on clay wheels. As everybody knows who’s ridden clay wheels, they’re not very fun. Anyway, Abe Powell, George’s son, went to Val Surf at the time and saw some urethane wheels. He came back to tell his dad about these urethane wheels that were really amazing. And so George went to take a look at them. Being the engineer that he was, he decided that he was going to make his own wheels in his kitchen. He made his first set of BONES in his oven. That’s how it started basically. I think it was 1975. In 1977, George poured the first white MDI (Diphenyl-Methane Di-Isocyanate) double radials and named them BONES because of the color.
WHY DID YOU BRAND BONES AS ITS OWN COMPANY SEPARATE FROM POWELL?
I think a lot of stores prefer to buy wheels from companies that stand on their own—their own entity. And when I took over BONES WHEELS in 2002, I really wanted that to happen, but I feared it never would because of the history. BONES and Powell were totally synonymous with each other before. Powell was everything, and BONES was just a subsidiary product within Powell. I think that with people who have been in the industry for a really long time, I’m never going to be able to change their mind. That’s not who I was trying to go after. I was actually wanting to market these wheels to the new kid who knows no history of Powell whatsoever. They see BONES WHEELS as its own entity, which allows me to take the BONES vibe in a different direction from Powell’s.
HOW HAS THE PROCESS AND TECHNOLOGY OF WHEELS EVOLVED OVER THE YEARS?
Wheel formulations pretty much didn’t change until 1990. And then when skateboarding changed and took to the streets, obviously the formulations had to change because kids wanted wheels that worked best for them in the streets, which was a harder, smaller, narrower wheel. What happened was that when we made our wheels harder, smaller and narrower, we were finding that they were flatspotting a lot easier, so we had to come up with something to resist flatspotting. That’s where Skatepark Formula (STF) came from actually. We developed the formula in-house and tested it out in The Skate Zone here, where a lot of kids were flatspotting their wheels because of the smooth floors. When you slide out, you’re creating a lot of heat, and a lot of MDI urethanes being used (in wheel manufacturing) are not heat resistant or abrasion resistant enough to resist this, so we went a completely different direction chemically and came out with Skatepark Formula. We’re really happy with it because it was superhigh abrasive resistant, so it was really hard to flatspot. And they lasted a lot longer, too, so it’s a much better wheel.
CAN YOU EXPLAIN THE DUROMETER SCALE?
Wheels are always gauged on an A scale, and on hardness there are four different scales—A, B, C, D. Starting from one going to 100—one being the softest and 100 being the hardest. Back in the ’80s, wheels were a little softer. They were anywhere from 80, 85 durometer to 90, 92, then they started getting a little harder and 97, 98 were about the hardest they ever got. We’re talking about a scale from one to 100 here. When street skating came out, the wheels started getting harder and they started surpassing the hardness of a 100. Today, most street wheels are actually between 99 and 105 “A,” but these hardnesses cannot be measured on the A scale, as they would all read about 99A, even though they are of significantly different hardness. Because kids were educated on an A scale, we just said it was a 101A. We guesstimated. We use a B scale, which gives us a very accurate reading on the hardness of the wheel, but it’s hard to transfer a B scale (durometer measurement) to an A scale. Like an 84B possibly could be about a 103, 104A, but there’s no such thing as a 103A.
WHY DON’T YOU USE THE “A” DUROMETER SCALE FOR THE STF AND SPF WHEELS?
STF and SPF wheels are harder than can be accurately measured by the A scale, but this is the only scale that skaters have ever gotten “calibrated” on and understand, so we had a choice of calling them 104A as we have in the past, or taking a different direction and stating what they were designed for, street or park. Getting into how we came up with the number 104A is an interesting story, and part of the BONES legacy, but perhaps more technical than most skaters care about. Also, I think if the kid reads the wheel as 104, he’s gonna think it’s too hard. But the urethane that we use—it needs to be that hard to ride the way it does. So we just use STF Street Tech Formula and SPF Skatepark Formula as the hardness. I think what we need to do is educate the kids on the B scale so that they understand it. It’s gonna take some time, but if everyone gets into it, we can have a way more accurate reading on wheels. My 101A wheel could be completely different from somebody else’s 101A wheel just because of the urethanes they use and because it is a guesstimate. There’s too many variables involved there.
SO THERE’S NO 101A?
There is no such thing as a 101A. It’s a marketing thing. If you’re riding a 99A and you get on a wheel that’s just a little bit harder, you can call it a 101A and you understand it. If I call it an 82B, you wouldn’t understand it at all. So we just came up with a number so kids could understand it. I’ve been noticing a lot more D scales being used, but you really can’t accurately gauge a urethane wheel with a D scale because the spring and the point (of the measuring tool) is really sharp and hard and tight. If you try to use a D scale durometer reader on a wheel, it would puncture the skin and not give you an accurate reading. So that’s why we use the B scale. It’s probably the best you can use.
WHAT’S DIFFERENT ABOUT YOUR FORMULA THAT MAKES BONES WHEELS TOO HARD FOR THE TRADITIONAL A SCALE?
It comes from a completely different derivative. Most of the wheels out there these days come from an MDI component, and we are starting with something completely different. We have chosen to go with a formulation name instead of a hardness because the material is about 84B, and cannot be measured on the A scale. So it rides different, it feels different. Hardness is a useful tool when it comes to categorizing urethanes, but it does not always provide a good gauge of the wheel’s performance.
About Wheel Hardness: The A scale is the most commonly used for measuring the hardness (durometer) of skateboard wheels. As wheels have becme harder over the years, however, many companies have found that the B scale more accurately measures their urethane. Some manufacturers also use the D scale, but mostly for measuring very hard plastic or urethane cores. As shown above, a lower number on the D scale (75D) actually represents a harder durometer than a higher number on the A (99A) or B (84B) scale. Because each scale was developed to rate a different level of hardness, there is no accurate method of conversion between scales.
WHY DO THE WHEELS LOOK PLASTICY?
Just because of the urethane that’s used and the pigment we put in it to make it white. Skaters prefer white wheels over any other color, so we had to make it white, which is not its natural color. Some people might think that our wheels look like a Chinese-made product, kind of plasticy looking, much like a clear wheel would be. I think because it’s a far superior quality urethane. It’s really expensive to use because it comes from a different derivative. To make it rideable, we have to make it harder. If I made that (STF wheels) at the same hardness as a regular MDI wheel, it’d be really, really grippy. So the harder we make it, the less grippy it gets. We have to heighten the hardness of it so it rides much like an MDI does.
WHAT DO YOU PUT IN IT TO MAKE IT HARDER?
Different ingredients. More of something and less of something else. The hardness of a wheel is not what makes it exceptional. It’s a blend of properties that make the wheel perform optimally in any given environment.
BUT WHAT’S DIFFERENT ABOUT IT?
That’s the secret ingredient that we can’t talk about.
OKAY, THAT’S WHAT I WAS TRYING TO GET OUT OF YOU. SO HOW DOES THE STF FORMULA WORK EXACTLY?
STF is the result of blending components together to obtain the properties you want. During the past 30 years, we have gotten very good at this in the specialized area of skate wheels. Our quest was to create a wheel that accelerated fast, rolled “forever,” gripped well, but could be released at will for controlled slides, and finally, did not flatspot easily. STF has achieved all these goals. Take our Skatepark Formula, for instance: I can say that that’s a great wheel for what it is. It’s a great wheel for high abrasion; for slippery surfaces, it grips really well. It’s a hard wheel, which makes it fast so you get higher rebound from it. It is hard, but it also grips on slippery surfaces and that’s why it’s so good for smooth cement or slippery surfaces like masonite or skatelite or whatever you’re using. It’s an awesome pool wheel, bowl wheel, and smooth cement wheel. The problem is that forstreet skating it’s a little grippy. So what we did is we took that compound and we had to work with it and come up with some ingredients that we can add to it so it would have some slipperiness to it. So it would slide out and act more like an MDI urethane, but still be able to resist flatspotting. That’s my main objective—to make a street wheel that didn’t flatspot.
After drag-testing STF against other companies’ wheels, Washburn and Powell were happy to see their formula lost 92% less material than a leading competitor’s.
WHAT WAS THE R&D PROCESS LIKE FOR THE STF FORMULA?
Basically, I knew what it took to make a wheel that my skaters would be stoked on. Like I said, the direction I was going was for the street skater. I wanted to make a good street wheel that didn’t flatspot. So to R&D it, we knew we already had a good urethane with the Skatepark Formula but we had to make it work for the street skaters. We tested a whole bunch of different urethanes, and nothing really came up. They all flatspotted and we were always having the same results. I would personally take a set of wheels and go powerslide the shit out of them and see how easy it was for me to flatspot them. Of course, most of the urethanes that I used flatspotted. What we decided to do was take our existing urethane and see if we can change it so it would slide without flatspotting. What we finally decided to do was start with our existing urethane and change its slide characteristics by adding some additives and ingredients using our experience in formulation development. Right away, we knew that was the direction we needed to go. So after many, many different tests, we fine-tuned it to a position where I thought it was good enough to send out to my team riders to try out. I got some good feedback, some bad feedback, and from there we just fine-tuned it to what we have today with the Street Tech Formula. As soon as I found out from my riders that it was right where they wanted it to be, I knew it was time to put it out on the shelves and let the kids get it.
BESIDES LETTING YOUR RIDERS TRY IT, DID YOU DO ANY OTHER TESTING?
Basically, we drag a set of four wheels bolted to a weighted sled a set distance on medium grit concrete to see how much material is taken off. Street Tech Formula lost only eight percent as much material as the best-selling white MDI wheels.
WHAT DO YOU MEAN? EIGHT PERCENT OF WHAT?
We took all our wheels and our leading competitor’s wheel and we weighed them. We drug them the same distance with the same amount of weight on them at the same speed. After we did that we weighed them again to find out how much material was taken off during the test. Ninety-two percent less material came off our wheel (than the leading competitor’s wheel). We knew that we had something good with Skatepark Formula, but then when we tested Street Tech Formula against that, it was far above and beyond.
WHO’S THE SCIENTIST BEHIND IT ALL?
George Powell. He’s the engineer here—the mad scientist. He knows everything about urethane. He’s been doing it since 1977. He keeps up with all the urethanes and new developments. George has developed every urethane innovation BONES has introduced over the years. I think he knew which direction to go.
WHERE ARE STF WHEELS MANUFACTURED?
Here in-house. And it stays here in-house. We obviously buy our raw materials from distributors, but everything is made here.
YOU DO ALL THE PRINTING HERE, TOO?
We do all the pouring, all the cutting, and all the printing here in Santa Barbara.
WHY BLACK AND WHITE GRAPHICS? KIDS LIKE COLOR, DON’T THEY?
I didn’t want to cater to the kids. I wanted to cater to the street skater, the real skateboarder. Everybody else was doing color, so there’s a pool of BONES wheels that are different from everything else. The simplicity of black and white makes it stand out as its own entity. That’s our image—black and white.
HOW DID YOU COME UP WITH THE GRAPHICS?
I’ve seen the mailbox silhouette. The other one is a light post and the other one is a fire hydrant. What we wanted to do was take urban elements and put them on our wheels in silhouette black. Super simple.
HOW IS STF DIFFERENT FROM WHAT OTHER WHEEL COMPANIES HAVE?
First of all, not everyone buys the same raw materials from the same suppliers. So right there we’re different. Some processors go for a very low-quality urethane, while we go for the highestquality urethane we can possibly get. Because we do everything in house, we can research and design and come up with our own formulations. We differ from everybody else because of that. I think a lot of other companies will go to a wheel manufacturer and have their wheels made by the same manufacturer as everybody else. They just stamp their graphic on it. You see a lot of that in this industry. There are other people who obviously pour their own wheels, but it’s getting rarer and rarer every day.
ARE STF WHEELS MORE EXPENSIVE THAN REGULAR WHEELS?
I think the Street Tech Formula is about the same as everybody else’s most elite wheel. Obviously, it’s not a pricepoint wheel. The reason why it’s more expensive for us to do is because obviously the raw materials are more expensive because it’s the highest quality urethane you can use at this point.
WHAT TYPE OF CUSTOMER WILL WALK INTO A SKATE SHOP AND BUY STF WHEELS?
I’m hoping the customers who want really good quality product, who want to get what they pay for, and don’t want a novelty item. They want something that’s gonna work well for them. Somebody that wants the best. The same person wants a set of Swiss bearings basically.
WHAT WHEELS DO MOST OF YOUR TEAM RIDERS PREFER?
They ride the new Street Tech Formula. There’s a couple of Am’s who still ride the BONES 100s because they prefer it. But I think everybody is riding the Street Tech Formula.
WHAT DO YOU SEE IN THE FUTURE FOR BONES WHEELS?
I want everybody to be riding them.
