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Several RC magazines around the world have asked us to write a monthly column. With the kind permission we will re-publish the column at our web site too so all of the XRAY fans can read the latest news and behind the scenes information. Enjoy.

Column #1 - Behind the Scene Stories

Column #2 - Worlds Flashback

Column #3 - T2'007 Debut

Column #4 - Designing the T2'007

Column #5 - Worldcup Review and NT1 Testing

Column #6 - Developing and Designing the NT1

Column #7 - Developing and Designing the NT1 - Part 2

Column #8 - Back to the Races

Column #9 - XT8 Truggy Development

Column #10 - Touring Car Development

Column #11 - Bling-bling Mentality

Column #12 - Hot Summer Washout

Column #13 - New Electric Touring Car

Column #14 - Off-road Development

The most difficult aspect of being a model car designer is to keep up with the constantly-evolving market trends and new requirements of the customers. My task list is extensive, and any time I finish the latest project I feel satisfied that another task has been successfully finished. and so I can move on to the next one. After we finished the new T2'008 electric touring car I was really happy to see the new project I had on my schedule: the update of the M18T micro truck. Why? Because I simply love the micros and any time we travel to the local races where are both 1/10 electric and 1/18 micro cars being run, I always take the opportunity to run the 1/18 cars as well. What I like about these cars is that they are so easy to drive for regular people such as myself. Over the years the micro market has changed a lot from its humble beginnings, and now it was my task to make a higher-performance M18T.

Back in 2004 we designed the M18T based on scale size, meaning we made the M18T exactly 1/18 scale with both the wheelbase and width true to the scale. To make the car lightweight we followed the same thought process as we did with the M18 on-road version, and made the whole platform from composite parts which ensured that the parts were light and strong. Of course we spent a good amount of time to adapt the proper different composite mixtures to the different parts depending on the parts' characteristics and purpose, whether is be chassis, drivetrain parts, suspension parts, the amount of load/stress, and performance purpose of each part.

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The original platform was very good and over time was very successful. The micro market has meanwhile moved from local club races into larger and more impressive events, and first national races are being organized. One of the biggest successes for the M18T was of course winning the US National Champion race where young XRAY driver Zack Barry won that big race 2 years in a row. I have kept watching the market develop and since then the racing scene has starting to move towards high-performance brushless systems, LiPo batteries, and better modified motors. As micros have evolving we have kept up ongoing development as well, and during that time have introduced several performance-enhancing parts including a graphite chassis to provide a more stiff & solid platform, optional aluminum adjustable ball-differential, alu drive shafts, alu shocks, alu steering blocks, and other parts to provide the customer with sufficient variety of tuning and upgrade parts to adjust the car for different racing conditions. but also to provide more solid platform for high competition racing.

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As the performance of electronics has been increasing, the parts of the car were getting more "load stressed" and as such the aluminum drive shafts which used to work very well with modified motors were starting to wear more, so a long-term solution was required. Racing has also moved from indoor tracks to dusty outdoor tracks where the pivot ball suspension with composite bushings suffered, and as such we needed to introduce nickel-plated steel suspension balls that would make the suspension work better. and longer. in dusty conditions. We also created a steel spur gear to be used in dusty outdoor conditions.

It was fairly easy to brainstorm about what we needed and wanted to improve and change for the new M18T. We needed to bring the platform to the new level of high-competition racing so as to meet and exceed the expectations for reliability and performance. The code project for the new car was set right away, to make a professional M18T and as such the name M18T PRO was set in place. The goal was set, we just had to work out all the details.

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The M18T was super-reactive and very fast on carpet indoor tracks since the car had a short wheelbase. But on bumpier tracks and big jumps the M18T was losing its competitive edge mainly due to the fact that we had kept true-to-scale 1/18th while competitor's new cars had longer wheelbases and wider tracks. So the first task was to improve the handling of the car in the bumps and on big jumps, and this could be done only by elongating the car so it would be better balanced. We have increased the wheelbase by 16mm and decided upon a different weight distribution and load for the suspension, with more weight moved towards the rear of the car. To ensure a solid platform I decided to go with a graphite chassis and top deck; definitely more expensive but necessary for high-competition racing. With the new chassis we could test different batteries and electronics placement, and for the final design we kept the batteries in the same position; since we moved the front suspension more forward, the weight moved to the rear. To keep with the XRAY philosophy of luxury performance, I decided to use the graphite material for the battery strap with a cool "X" symbol milled into the middle of the strap. With the new chassis on the design board we could also incorporate more holes for servo stands to allow a broader range of micro servos to fit the car. We decided upon the aluminum adjustable motor mount to make sure that the holder would be stiff enough to key mount all current high-performance motors, and the variety of mounting positions also ensures that any of the most popular motors can be easily mounted.

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With the improved performance of the car we also needed to improve the reliability and strength of those parts which were already being taxed by the high performance of brushless power plants. The first and foremost challenge was to make reliable and super-strong drive shafts. The composite ones of course were not usable for high-performance motors so we started to look and work around the aluminum drive shafts as they are light and strong, but we needed to change the shape and design to withstand crashes and withstand high-powered power plants. Doing tests with some new designs I was happy that the drive shafts improved in reliability, but I was still not convinced that we had completely solved the lifespan issue. It would be easy to make a short-term solution, but I needed to be sure that the new drive shafts would be a long-term solution that will stand up to the abuse of high-competition racing and survive the awesome power of more and more powerful electronics. In the end I decided to use the very best material available on the market - HUDY Spring Steel™. After designing the drive shafts from HUDY Spring Steel™ and getting the first prototypes to test, I was pleasantly surprised by their performance and especially their reliability. Despite being a little bit heavier, the difference in reliability was so big that I decided not to compromise the quality of the car and the HUDY Spring Steel™ parts were definitely going into the kit. To compensate for the slightly increased rotating mass of the HUDY Spring Steel™ drive shafts, I needed to reduce rotating mass somewhere else; the best and final solution was to use a very lightweight (but immensely strong) graphite main shaft.

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As the M18T has been mainly oriented for indoor racing I needed to minimize the problems encountered in dusty outdoor tracks. Replacing the standard composite pivot balls (which are great for indoor racing) I decided to use nickel-plated steel pivot balls; this will most certainly help in the outdoors. When running outdoors in dusty conditions, it is vitally important to check the car after each run, clean the car thoroughly, and ensure that the suspension moves freely. In dusty conditions, the wear rate of the pivot balls is higher and as such increased servicing and attention is required. The other new part that will help the car in outdoor conditions is the steel spur gear which will ensure that if hard debris (such as a stone) gets into the gears it will not break the teeth. However, when racing indoors the standard composite spur gear will still work great as it is lighter and reliable for those conditions. To make sure that the car will have the best specs for both types of tracks, we will include both spur gears in the kit, so the driver can decide on the proper spur gear (composite or steel) based on the racing conditions.

Talking about adjusting the car, we tried to incorporate all the different set-up features into the car and as such not only the diffs or shocks are adjustable but also toe is adjustable via adjustable tie rods. With the new weight balance, new wheelbase, and new features of the car, I was convinced that the car would handle well and be easy to drive especially in bumpy conditions and over big jumps. While doing the long-term tests and comparisons, I have enjoyed the consistency and easier handling of the car. This has allowed me to concentrate more on racing so the overall result was better, which was really great and I was ready to put the car into production.

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Finishing the design, we produced several pre-production cars which were handed over to several team drivers to test and gather feedback. My expectations were confirmed shortly thereafter with positive feedback from the drivers. Zack Barry, 2x US Champion reported the following after the first day of practice:

"We just got back from practicing all day for the 18th-scale nationals. And I just wanted to let you know that the new truck is AMAZING!!! It handles the corners a lot smoother and drives a lot better. We have someone painting a body for us tonight and will be ready tomorrow for racing. Thank You....Zack"

The positive feedback from Zack was really great and made me relieved. Afterwards, the newly-designed truck prevailed at the 18th-scale nationals, with Zack winning the Open Truck category on a smooth track. At that moment I knew that the M18T PRO would be the "toast of the town" of the high-competition crowd, and put more drivers into the winning circle again. Having the production in-house we could put on the green light for the project and in just a very short time - within a few short weeks - we have produced the whole big batch ready to get it out to the Xmas market, so I hope plenty of XRAY fans will find a small (micro) present under their Xmas tree. Not only will the car itself make them happy, but I am convinced the performance will drive them crazy!

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Enjoy the ride and â€til next time…

Dipl. Eng. Juraj Hudy
Chief Designer XRAY