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Old Jan 09, 2012, 10:47 AM
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Jacksonville, FL
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OFNA JL12e

My neighbor has some hopped-up HPI and Associated 1/18th scale cars. They are plenty fast, and looked like a lot of fun. I had been out of the R/C car hobby for some time, and after driving one these, I was hooked again. These tiny cars did around 50mph but were twitchy as hell. The same speed in a more stable car for bashing around the neighborhood seemed ideal. From previous experience I really liked the 1/12 (or the now 1/10th mini) size, and so my search began.

After much research I came across the OFNA JL12e on a few shops online, and found a couple favorable reviews. Turns out it is a very respectable chassis, based on the Active Hobby A210DS, with a really ugly body. Seemed like an amazing value, which is good as finances are very tight at the moment. That really sweetened the deal. It has as standard nice shocks, ball bearings throughout, a ball diff, a basic 2.4 GHZ radio (I don't care for any frills, anyway) and everything but a charger and batteries. The motor was a very unimpressive looking bushed, 23T, stock-style can on a very nice anodized aluminum mount.

After getting everything in, as soon as batteries were charged it was off. A lot of these RTR's seem to have random loose fasteners, so I checked over most that are critical (or so I thought).



The body is a PVC Suzuki Swift. They really coulda done better here.


This would've been much better:


In any case, after some motor break-in time, the car immediately impressed. My neighbor thought it was brushless. It was capable of, we estimated, about 45-50 mph. The tires seemed to be between a drift tire and race tire. It wasn't quite slick enough to drift properly, and not quite sticky enough to make fast turns. The best compromise seemed to be squaring-off turns under throttle. It was very hard to keep straight under full throttle, as the tires would only hook up on very gradual applications of thrust. The ESC and motor got a bit hot, but not alarmingly so. Very happy, and very impressed, I put it up until the next day.

Having a little more confidence in my abilities, my five year old son (who finds it as much fun to watch as I do driving) and I went to a local lot. The street has inclined curbs which are very forgiving. The parking lot has tall, square curbs that threaten to destroy. After a lot of fun blasting up and down the lot the car got very twitchy in the front end, eventually darting towards a curb at around 45mph. I tried to slow and recover but it ended up hitting pretty hard. The cheesy body got cracked up, the wheels all got scraped, and the right front wheel and steering knuckle were dangling there. Scared at first, I noticed that the assembly just popped off from the ball joints. After putting things back together it was evident that a front wheel had come loose. Shoulda checked that! A bit disappointed, we made our way back home, with the car trolling ahead. In front of the house just one block from the lot the car quit. Dead battery, already? I picked up the car and heard a crackling sound then smoke. I ran to the door, popped the body, and unplugged the battery. The motor, ESC, and switch all fried spectacularly. Thankfully the chassis did not melt. Needless to say, I have a 12T brushless and 35A ESC on the way, and will get a new body and maybe a set of wheels/tires as soon as I can.

I'm thinking something like this:


To their credit OFNA sent a new motor and ESC right away, and also checked my receiver to insure it didn't get smoked. I did find a small rock near the belt also which may have stopped the car, but the throttle came off immediately so I have no faith in that ESC.

Overall I love the car, even with the cheap cheesy body and explodie ESC. With a brushless it should really rip (even though it is already fast enough for me) and with a proper body (see below) it will have looks that do it justice.

Another great body idea:
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Last edited by Rick_A; Jan 09, 2012 at 12:46 PM. Reason: Typo in title, pic add
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Old Feb 10, 2012, 11:33 PM
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Jacksonville, FL
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The Saga Continues...

The OFNA JL12E/Active A210DS got some upgrades in the way of a EZ-Run 12T motor and a Turnigy 35A ESC. After some setup time and a few test runs I ran out to the local basketball court to have some fun. After only about two minutes the car lost some speed and would veer one way on the throttle, and the other on the brakes. I knew immediately that a front axle had broken. Before then the car was screaming; running so hard it would not hook up in the slightest. That didn't last very long. A couple axles went on order.


Once the axles came in the offender was replaced. My neighbor felt the failure was a fluke. I wasn't so sure. The motor got pretty hot with the timing set at default in short time, the speed was a bit much, and the takeoff power made it nearly uncontrollable. The "punch" setting was set to mid, and the timing was backed to zero. The power was then smooth and controllable. A tendency for the steering to wander, not stay at a consistent center, and understeer had me adjust the toe in considerably from the factory setting. After a few test runs and experimentation, setting the front toe to mimic the rear improved things substantially. Next, with the battery in place, the ride height, sag, preload, and camber were adjusted, which were all a bit wonky as built. A little understeer remained but the car was then arrow straight under acceleration, and otherwise very neutral handling. The run time is great, probably close to 20mins under a lot of heavy throttle. Top speed has suffered with the timing set back, but the motor temp seems a lot safer. Maybe with a motor fan I'll get more aggressive with it...or perhaps a gearing change.

The first full run with the adjustments and new axle was a blast. Unfortunately another front axle blew after about 15mins. After replacing that, on the next run, I could hear a rear axle starting to chatter. The pin was beginning to slip out. It looked like heat/friction were causing the pins to slide out, creating an uneven torque that would split the drive cup apart.


To combat the issue the pin was adjusted back where it belonged, and a dry-film motorcycle chain lube was used on the joints. This stuff lubricates bare metals well, and will not attract dirt. Time will tell if these hold up.

The strength of the chassis was really put to the test when I jumped to avoid getting hit. The car came to an impossible stop from speed just beneath my foot. The body was pancaked comically, with a corner broken, but the car was otherwise unscathed. I popped the body back into shape and she was no worse for wear.

As long as I can get these axles to survive, this car is really working well, once sorted out. It has also proven to be ridiculously strong, surviving getting stomped by a 190lb man.
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Old Feb 13, 2012, 08:28 PM
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Jacksonville, FL
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Conclusion

After another couple runs it seems the powerplant is overwhelming the axles. To keep from breaking them outright, I am forced to do some axle maintenance as soon as I start hearing them chatter. It generally happens near the end of every run. I've had no luck finding an upgrade for these, so it'll likely be a continual annoyance.

Other than that, this is the only issue:

The tires are blazed after about seven runs.

Out at the local basketball court with my neighbor and his Mamba equipped RC18R, though my car was unable to hook-up on the surface, it was still able to keep up with his. An RC18R was the first car I was interested in, and I'm glad I went this route (axle issue notwithstanding). His car had to be feathered like an old miniature slot racer with weak magnets or it would be sent tumbling. Mine could be held almost flat-out, with a touch of brake/throttle modulation to get it backed-in and turned. A better set of tires may change things (and likely amplify the axle issues), but my main concern at the moment will be getting a set of tires that will last longer than two hours.

Overall, the car is a pure joy to drive once set-up the way it likes. It is tough and neutral handling, though there is a touch of understeer remaining on the throttle (more fiddling may fix this as well). The only downside is the fragile axles when a little more power is introduced. At $20 a pair, and having no local supply for these, breaking them and/or tweaking them constantly is getting old fast. This will likely not be an issue set-up as sold or with a milder brushless set-up.
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Old Feb 13, 2012, 09:26 PM
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I think the root cause of you breaking these axles is due to the pins slipping out, as you pointed out. If they're made of steel, which I think they are then they should be strong enough to be able to handle the additional power. What you can do to prevent the pin from slipping out is to add a little bit of thread lock to the set screw that holds the pin in place and/or add a piece of heat shrink to cover up the holes in the axle cup. If you can grind a small flat spot on the pin and have the screw fit against the flat spot that would be even better. This is often done to suspension pins that use set screws so they don't slip out.
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Old Feb 14, 2012, 07:59 PM
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Jacksonville, FL
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I have considered all that (though the heat shrink idea is something I had not considered). The set-screws are already tight and locktited-in. They are in there so tight the heads were either already rounded-off on installation or are completely stuck. In the past, even when red-hot, I've had issues getting little screws like those out of similar assemblies. I'll see how the heat shrink works. Thanks.
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Old Feb 20, 2012, 09:49 PM
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Jacksonville, FL
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As TueLe suggested, the axles were shrink wrapped around the joint. So far so good. A new body and wheels/tires were installed. I snapped a few quick pics as they would not look good for long.



Some chassis and suspension dis-assembly had to be done to work with the axles and re-locate body mounting posts. Unfortunately the steering is back to being all over the place despite my best efforts to restore some stability. The steering servo seems to have developed a lot of play on the output shaft. Another frustrating issue to deal with. Other than that it is all sorted out and finally looking as it should.
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Last edited by Rick_A; Feb 21, 2012 at 11:55 AM. Reason: Errors
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Old Mar 29, 2012, 07:55 AM
MD6
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Thanks for the information. Has anyone else run this car?
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Old Jan 20, 2013, 04:32 PM
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A group of us racers in nc have bought these cars and like them we race them in a gt mini class against tamiya m chassis and some abc hobbies cars. But alot of us are getting mad . Because we are sidelined due to a very very simple cheap part . The a-arms We have searched high and low and absolutly no one has them not even nitro warehouse witch is ofna direct basicaly . so we are starting to wonder if we have a very $$$$ paper wieght due to not being able to buy a $ 3.00 part . I have personally emailed ofna direct to address this issue . Hoping to hear back from them soon . it is all over part #70025 and cost $2.95 . it wouldnt hurt for more to email ofna over this issue as alot of people in the usa own this car and they are still selling them at towerhobbies aswell as ofnawarehouse.com and nitrowarehouse.com .. we are gonna be very very mad if we cannot race anymore due to the lack on ofnas part to produce a simple $3.00 part to its consumers If they do not fix this issue i for one will never buy another ofna product and will do my best to tell my friends and local hobby shop owners about this and warn them to stay away .
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Old Jan 20, 2013, 04:53 PM
MD6
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http://www.activepowersports.com/ofn...l12e-ofn70025/

http://www.hobbyfever.com/shop/produ...j5hf9got4pnp37

I found the above places that indicate they have the part, but with active power sports it may not be accurate.
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