TheJANG
12.28.08, 7:26 pm
Update 2/19/2010: The project is now complete. See the full info, including final photos and a VIDEO at:
http://www.ultimaterc.com/projects/minitaur/ (http://www.ultimaterc.com/projects/minitaur/)
Background:
This project began in 2003 as the world's first 540 BL-powered Mini-T. With an unbeatable amount of power at birth, I quickly christened the project as the "Ultimate Mini-T" and started the long process of modifying the rest of the vehicle to match the insanity of the motor. Lucky for me, the Mini-T itself was a brand new release, so aftermarket support was non-existant, giving me tons of opportunities to innovate.
I modified two Associated Micro VCS shocks (from an 1/12th pan car) and two GPM touring car shocks to set up the very first proper-fitting full oil suspension seen on one of these trucks. I followed this up with one of the first (if not the first) proper-fitting servo upgrades with a modified Airtronics 94091 "super micro" unit, which would later become a very popular upgrade when Airtronics itself released a conversion kit. Knowing traction would be a problem with the big powerplant, and also just following the general "bigger is better" theory, I went to work on a wheel/tire solution. Clever use & modification of adapters allowed me to put a set of 2.2" buggy tires all around, mounted to HPI buggy wheels up front (made for Kyosho cars) and Super Nitro rears. The net result was... interesting?
http://www.ultimaterc.com/gallery/albums/userpics/10001/norm_smash_tires.jpg
Obviously the proportions were completely wack. A lot of measurement & sketching, and several prototypes later, and I had a very nice 5-piece carbon fiber & Delrin chassis conversion installed, extended by an inch and capable of holding a 6-cell side by side battery pack right along the centerline like a 1:10th scale.
http://www.ultimaterc.com/gallery/albums/userpics/10001/norm_side.jpg
After adding some aluminum bits and mounting all of the electronics (the white thing is a BEC), I had a complete, working, awesome little truck.
http://www.ultimaterc.com/gallery/albums/userpics/10001/norm_040711%20020.jpg
Unfortunately, two problems lingered. First, the KAN 1050mAH 2/3 A cells weren't going to be able to deliver the juice the big BL motor could drink up. I addressed that problem by doubling them up with this unique 10-cell brick (http://www.minioffroaders.com/minit/battery.jpg) hardwired as two 5-cell packs in parallel. That fit very nicely in the battery compartment and allowed the truck to hit 31mph on a test run, pulling wheelies at nearly any speed, even with all of that weight to contend with.
The second problem seemed like a whole lot of nothing at first, but it would prove unbelievably daunting, throwing the whole project into a major crisis. The issue was the body. There was simply nothing that would fit. I first did up a Micro RS4 pickup body, and while that "fit," it didn't fit. See for yourself (http://www.ultimaterc.com/gallery/displayimage.php?pos=-1229). There was no way I could brand something as a complete "Ultimate" project if it didn't look good, no matter how it performed. Eighteen months would pass before I overcame this obstacle and touched the truck again.
The wheelbase of the body I chose, which I promised not to show until it's mounted, was slightly longer than even my extended chassis accomodated, so I had to tear things apart in the shop yet again. This round of updates yielded this (http://www.minioffroaders.com/minit/ultimate/060811-mini_t-001.jpg) new main chassis plate, augmented by two vertical plates arching over the new low-cg battery layout, which you can see in place here (http://www.minioffroaders.com/minit/ultimate/070415-mini-t-013.jpg). A little more cleverness and some painstaking filing & soldering work yielded a battery terminal setup that allowed me to use the two packs in either parallel or series by just flipping one around -- no adapters required.
Update 12/28/08!
I decided on a body in March of 2006. As of this writing, it's almost 2009. Motor system and battery technology readily available to hobbyists has improved by leaps & bounds since I started this truck, and I've finally broken down & convinced myself to let go of the original constraints of the project and get with the times.
The big 540-sized motor has since been used in the 1/8th scale \BACKSLASH (http://www.ultimatetraxxas.com/projects/backslash/), and it won't be making its way back into the Mini-T. Instead, I'll install my appropriately-sized mini Mamba system (Mamba 25 controller, 6800kV 20mm motor), and power it with a single lipo battery pack that weighs less than half as much as the NiMHs.
http://www.ultimaterc.com/projects/minitaur/ (http://www.ultimaterc.com/projects/minitaur/)
Background:
This project began in 2003 as the world's first 540 BL-powered Mini-T. With an unbeatable amount of power at birth, I quickly christened the project as the "Ultimate Mini-T" and started the long process of modifying the rest of the vehicle to match the insanity of the motor. Lucky for me, the Mini-T itself was a brand new release, so aftermarket support was non-existant, giving me tons of opportunities to innovate.
I modified two Associated Micro VCS shocks (from an 1/12th pan car) and two GPM touring car shocks to set up the very first proper-fitting full oil suspension seen on one of these trucks. I followed this up with one of the first (if not the first) proper-fitting servo upgrades with a modified Airtronics 94091 "super micro" unit, which would later become a very popular upgrade when Airtronics itself released a conversion kit. Knowing traction would be a problem with the big powerplant, and also just following the general "bigger is better" theory, I went to work on a wheel/tire solution. Clever use & modification of adapters allowed me to put a set of 2.2" buggy tires all around, mounted to HPI buggy wheels up front (made for Kyosho cars) and Super Nitro rears. The net result was... interesting?
http://www.ultimaterc.com/gallery/albums/userpics/10001/norm_smash_tires.jpg
Obviously the proportions were completely wack. A lot of measurement & sketching, and several prototypes later, and I had a very nice 5-piece carbon fiber & Delrin chassis conversion installed, extended by an inch and capable of holding a 6-cell side by side battery pack right along the centerline like a 1:10th scale.
http://www.ultimaterc.com/gallery/albums/userpics/10001/norm_side.jpg
After adding some aluminum bits and mounting all of the electronics (the white thing is a BEC), I had a complete, working, awesome little truck.
http://www.ultimaterc.com/gallery/albums/userpics/10001/norm_040711%20020.jpg
Unfortunately, two problems lingered. First, the KAN 1050mAH 2/3 A cells weren't going to be able to deliver the juice the big BL motor could drink up. I addressed that problem by doubling them up with this unique 10-cell brick (http://www.minioffroaders.com/minit/battery.jpg) hardwired as two 5-cell packs in parallel. That fit very nicely in the battery compartment and allowed the truck to hit 31mph on a test run, pulling wheelies at nearly any speed, even with all of that weight to contend with.
The second problem seemed like a whole lot of nothing at first, but it would prove unbelievably daunting, throwing the whole project into a major crisis. The issue was the body. There was simply nothing that would fit. I first did up a Micro RS4 pickup body, and while that "fit," it didn't fit. See for yourself (http://www.ultimaterc.com/gallery/displayimage.php?pos=-1229). There was no way I could brand something as a complete "Ultimate" project if it didn't look good, no matter how it performed. Eighteen months would pass before I overcame this obstacle and touched the truck again.
The wheelbase of the body I chose, which I promised not to show until it's mounted, was slightly longer than even my extended chassis accomodated, so I had to tear things apart in the shop yet again. This round of updates yielded this (http://www.minioffroaders.com/minit/ultimate/060811-mini_t-001.jpg) new main chassis plate, augmented by two vertical plates arching over the new low-cg battery layout, which you can see in place here (http://www.minioffroaders.com/minit/ultimate/070415-mini-t-013.jpg). A little more cleverness and some painstaking filing & soldering work yielded a battery terminal setup that allowed me to use the two packs in either parallel or series by just flipping one around -- no adapters required.
Update 12/28/08!
I decided on a body in March of 2006. As of this writing, it's almost 2009. Motor system and battery technology readily available to hobbyists has improved by leaps & bounds since I started this truck, and I've finally broken down & convinced myself to let go of the original constraints of the project and get with the times.
The big 540-sized motor has since been used in the 1/8th scale \BACKSLASH (http://www.ultimatetraxxas.com/projects/backslash/), and it won't be making its way back into the Mini-T. Instead, I'll install my appropriately-sized mini Mamba system (Mamba 25 controller, 6800kV 20mm motor), and power it with a single lipo battery pack that weighs less than half as much as the NiMHs.