News Item: : E-MGT or RC8MT. Either way, it lives. Are you paying attention Associated?
(Category: Music)
Posted by cotharyus
Tuesday 08 July 2008 - 20:07:38
Although some of you have heard rumors, others have seen pictures here on the site, and participated in discussions here and other places, others may be completely clueless, because I never officially posted this project. I\'m know as a fan of electric R/C cars, it\'s what I started with, and there\'s something special about them. Unfortunately, electric is viewed as expensive - motor maintenance, batteries with short run times, chargers. You get the point. Nitro gained a lot of popularity, and with 1/8 scale monster trucks, it hit a sweet spot. They work for racing, bashing, fantastic feats of R/C flight - they\'re big, tough and impressive. Unfortunately, they\'re also loud, messy, and there\'s a lot to take into consideration when you transport one. Lets face it, electric is simpler, but until very recently, there was nothing to match the scale and go anywhere capability of a nitro monster truck.
Recently, we got the E-Savage, and the E-Revo. I won\'t get into these here, but suffice to say the E-Savage isn\'t brushless, and the E-Revo, is not, in my opinion, a monster truck, it is something different. It\'s cool, but it\'s different. Plus, I already have radios, servos - I really wanted something I could bend to my own needs, something big, four wheel drive, and fast. I\'ve been racing a Monster GT for some years. I like it, and would never get rid of it, or do away with it. So when I heard about the Mamba Monster Max ESC, something that would finally stand the current it would take to really sling around a big heavy monster truck, I started looking around. A local racer was retiring all of his nitro gear, and selling a Monster GT rolling chassis. I bought that, worked it over, and eagerly waited for the MMM to become available, while planning out how it would work, and go together. Finally, everything was on the market.
The ESC:
The Mamba Monster Max is one bad animal. Capable of handling 200 amps constant load with up to 6s LiPo, equipped with a fan and 10 gauge wires, there\'s nothing that compares to it. And since it\'s a Mamba, from Castle Creations, it is, of course, programmable via your computer. I would like to say it\'s everything I expected, but Castle slipped in one place. This ESC has a 4.8 volt (or something less than 6 volts) BEC which is non adjustable. It would have been better for something designed for large vehicles to have more voltage available to servos, in my opinion. That said, this ESC has dealt with three runs, of increasing punishment, and never gotten over 115 degrees F, even though one run the ambient temperature was at least 97 degrees F. I have to plug my vendor, Holmes Hobbies, owned by John Rob Holmes. He told me he\'d get these in, and he did. I ordered mine from him, and had it in my hands, like always, more quickly than I had expected. There are people out there dedicated to excellent service, and John is one of them, I make it a point to do business with these people every time I get a chance. Additionally, John will supply you with information above and beyond what you can find elsewhere - believe me when I tell you, he tests this stuff, and probably abuses it worse than many of his customers.
The Motor:
The Medusa V2 motor powering this rig is a 4 pole brushless design. Rated at 2000kv, with a constant current draw rating of 89 amps, it\'s not going to stress the ESC. In fact, I wondered if it would be motor enough to heave this heavy truck around. It is. It\'s gotten the truck to over 30 MPH in (fairly tall) grass, up hill in my yard, it pulls massive wheelies, and it\'s super responsive on the track, the motor ESC combo allows power to come on hard enough to break the tires loose in a turn and provides enough control to allow a smooth slide through turns, continuing to roll on the power coming on to the straight - it\'s just plain fast. These motors are also relatively inexpensive compared to a lot of motors in this class, but I have to admit, the motor is certainly the weak link in this rig at the moment. It reached 180 degrees F on the same run the ESC hit 115F. On the same runs, the batteries came under the temp gun and showed ....97F - the ambient temperature. Eventually, this motor is going to be upgraded, although based on the mounting I\'m currently using, I may have to rebuild my mount when I replace it.
The Batteries:
The key to brushless performance, as anyone who has used brushless gear will tell you, is good batteries. That means batteries that can supply the current that a system needs to start up, the more current, the more explosive the acceleration, the more impressive the wheelies...you get the point. So how much current is enough? If you\'re shooting for a big rig, get as much as you can. My MaxAmps 8000 Mah 11.1 cell LiPos are capable of deliving 160 amps of continuous power. Wired up to throw both of them in at 22.2 volts, they\'ll spin the 2000kv motor up to 44k rpms, and with that much current on tap, it gets there fast. Now another word about a vendor. These guys at MaxAmps are top notch. I use their batteries in just about everything I own. Their service is fantastic, support is responsive, and they will discuss requirements for a project like this with you. Add to that reasonable prices (heck, fantastic prices if you consider the quality of the product you\'re buying) and I have to say it again - projects like mine would go no where without some of the fantastic independent vendors in this market.
With all the major components together, I built the motor mount from a steel shelf plate. A single thickness bolts to the chassis where the nitro mount fit to allow for gearing adjustment. A double thick upright to mount the motor to which is first welded together, then welded to the base with an overlap joint (one peice welded to the top flat of the plate the bolts to the chassis, the other welded to the outside edge) gives the motor mount enough beef to stand up to the torque this rig is making. I have not yet seen any sign of the mount flexing.
One major consideration was brakes. The MGT tranny is tough as nails, but there\'s no way to set it up to use the motor braking. You can also drop a half a pound out of the tranny by using the Associated Forward Only Kit. So I dropped in the FOC, and kept the mechanical brakes that are stock. They\'re good enough to stand the truck on it\'s nose anyhow. Downside - no reverse - upside, I might be good enough to not need it.
End results? It works. It\'s a sight to behold. it\'s nowhere near finished, I still have to sort out the suspension for a 13.5 lb truck, but there\'s no lack of power to tap here, and the future is wide open. Keep an eye out for updates, as this is sure to be a work in progress for some time. I also plan to have one of my photographers take some action pictures at some point. In the meantime, there are pictures in the image gallery here.
This news item is from The Control Room
( http://cotharyus.net/news.php?extend.31 )
(Category: Music)
Posted by cotharyus
Tuesday 08 July 2008 - 20:07:38
Although some of you have heard rumors, others have seen pictures here on the site, and participated in discussions here and other places, others may be completely clueless, because I never officially posted this project. I\'m know as a fan of electric R/C cars, it\'s what I started with, and there\'s something special about them. Unfortunately, electric is viewed as expensive - motor maintenance, batteries with short run times, chargers. You get the point. Nitro gained a lot of popularity, and with 1/8 scale monster trucks, it hit a sweet spot. They work for racing, bashing, fantastic feats of R/C flight - they\'re big, tough and impressive. Unfortunately, they\'re also loud, messy, and there\'s a lot to take into consideration when you transport one. Lets face it, electric is simpler, but until very recently, there was nothing to match the scale and go anywhere capability of a nitro monster truck.
Recently, we got the E-Savage, and the E-Revo. I won\'t get into these here, but suffice to say the E-Savage isn\'t brushless, and the E-Revo, is not, in my opinion, a monster truck, it is something different. It\'s cool, but it\'s different. Plus, I already have radios, servos - I really wanted something I could bend to my own needs, something big, four wheel drive, and fast. I\'ve been racing a Monster GT for some years. I like it, and would never get rid of it, or do away with it. So when I heard about the Mamba Monster Max ESC, something that would finally stand the current it would take to really sling around a big heavy monster truck, I started looking around. A local racer was retiring all of his nitro gear, and selling a Monster GT rolling chassis. I bought that, worked it over, and eagerly waited for the MMM to become available, while planning out how it would work, and go together. Finally, everything was on the market.
The ESC:
The Mamba Monster Max is one bad animal. Capable of handling 200 amps constant load with up to 6s LiPo, equipped with a fan and 10 gauge wires, there\'s nothing that compares to it. And since it\'s a Mamba, from Castle Creations, it is, of course, programmable via your computer. I would like to say it\'s everything I expected, but Castle slipped in one place. This ESC has a 4.8 volt (or something less than 6 volts) BEC which is non adjustable. It would have been better for something designed for large vehicles to have more voltage available to servos, in my opinion. That said, this ESC has dealt with three runs, of increasing punishment, and never gotten over 115 degrees F, even though one run the ambient temperature was at least 97 degrees F. I have to plug my vendor, Holmes Hobbies, owned by John Rob Holmes. He told me he\'d get these in, and he did. I ordered mine from him, and had it in my hands, like always, more quickly than I had expected. There are people out there dedicated to excellent service, and John is one of them, I make it a point to do business with these people every time I get a chance. Additionally, John will supply you with information above and beyond what you can find elsewhere - believe me when I tell you, he tests this stuff, and probably abuses it worse than many of his customers.
The Motor:
The Medusa V2 motor powering this rig is a 4 pole brushless design. Rated at 2000kv, with a constant current draw rating of 89 amps, it\'s not going to stress the ESC. In fact, I wondered if it would be motor enough to heave this heavy truck around. It is. It\'s gotten the truck to over 30 MPH in (fairly tall) grass, up hill in my yard, it pulls massive wheelies, and it\'s super responsive on the track, the motor ESC combo allows power to come on hard enough to break the tires loose in a turn and provides enough control to allow a smooth slide through turns, continuing to roll on the power coming on to the straight - it\'s just plain fast. These motors are also relatively inexpensive compared to a lot of motors in this class, but I have to admit, the motor is certainly the weak link in this rig at the moment. It reached 180 degrees F on the same run the ESC hit 115F. On the same runs, the batteries came under the temp gun and showed ....97F - the ambient temperature. Eventually, this motor is going to be upgraded, although based on the mounting I\'m currently using, I may have to rebuild my mount when I replace it.
The Batteries:
The key to brushless performance, as anyone who has used brushless gear will tell you, is good batteries. That means batteries that can supply the current that a system needs to start up, the more current, the more explosive the acceleration, the more impressive the wheelies...you get the point. So how much current is enough? If you\'re shooting for a big rig, get as much as you can. My MaxAmps 8000 Mah 11.1 cell LiPos are capable of deliving 160 amps of continuous power. Wired up to throw both of them in at 22.2 volts, they\'ll spin the 2000kv motor up to 44k rpms, and with that much current on tap, it gets there fast. Now another word about a vendor. These guys at MaxAmps are top notch. I use their batteries in just about everything I own. Their service is fantastic, support is responsive, and they will discuss requirements for a project like this with you. Add to that reasonable prices (heck, fantastic prices if you consider the quality of the product you\'re buying) and I have to say it again - projects like mine would go no where without some of the fantastic independent vendors in this market.
With all the major components together, I built the motor mount from a steel shelf plate. A single thickness bolts to the chassis where the nitro mount fit to allow for gearing adjustment. A double thick upright to mount the motor to which is first welded together, then welded to the base with an overlap joint (one peice welded to the top flat of the plate the bolts to the chassis, the other welded to the outside edge) gives the motor mount enough beef to stand up to the torque this rig is making. I have not yet seen any sign of the mount flexing.
One major consideration was brakes. The MGT tranny is tough as nails, but there\'s no way to set it up to use the motor braking. You can also drop a half a pound out of the tranny by using the Associated Forward Only Kit. So I dropped in the FOC, and kept the mechanical brakes that are stock. They\'re good enough to stand the truck on it\'s nose anyhow. Downside - no reverse - upside, I might be good enough to not need it.
End results? It works. It\'s a sight to behold. it\'s nowhere near finished, I still have to sort out the suspension for a 13.5 lb truck, but there\'s no lack of power to tap here, and the future is wide open. Keep an eye out for updates, as this is sure to be a work in progress for some time. I also plan to have one of my photographers take some action pictures at some point. In the meantime, there are pictures in the image gallery here.
This news item is from The Control Room
( http://cotharyus.net/news.php?extend.31 )