|
IOwnCalculus posted:Sticks to control cars?
|
# ? Apr 20, 2018 02:43 |
|
|
# ? May 27, 2024 03:22 |
|
IOwnCalculus posted:Sticks to control cars?
|
# ? Apr 20, 2018 07:45 |
|
kuffs posted:
Nice work! The details on the body look great, and those Pit Bulls are tucked just right.
|
# ? Apr 20, 2018 08:46 |
|
Let the kids chase the Granite around the park on the stock brushed/nimh combo. ....Then went and bought a 3s pack and Castle SCT brushless combo for it. ...Too bad i can't find half my drivers or my solder.
|
# ? Apr 22, 2018 00:17 |
|
IOwnCalculus posted:Sticks to control cars? You Am I posted:Careful there, British RC racers will get upset with you Pretty much. I never realised people saw anything odd about it.
|
# ? Apr 22, 2018 00:35 |
|
I've been looking into getting an R/C car with which to build a robot for a competition called RoboMagellan, and potentially another robotics competition organized by Sparkfun: http://robogames.net/rules/magellan.php https://cdn.sparkfun.com/assets/1/2/2/2/b/AVC-Speed-Demon-Rules-2017.pdf The idea is, I'd be mounting a GPS, camera, Jetson board, and other stuff on it and having it drive itself. My main criteria would be: -No trouble with wet grass that's slightly overdue for mowing (according to someone who's been there, in past competitions many vehicles based on small R/C vehicles have gotten stuck when the competition ends up happening right after a rainstorm) -Capable of climbing up a ramp with bits of 2x4 nailed to it (so I'd be looking for large tires and fairly high ground clearance). -Large enough to handle having 2-3 pounds of electronics bolted to it -Stable cornering at moderate speed (realistically, my sensors would likely limit me to around 30mph tops) I was originally considering the Traxxas X-Maxx, but the Sparkfun competition has a weight limit of 25 pounds. I've also considered the slightly smaller CEN Colossus XT. Does anyone here have any experience with that, or know of anything else that would meet the above criteria?
|
# ? Apr 22, 2018 03:53 |
|
Today I drove 1/5 cars with other friends that have 1/5 cars for a few hours. One friend was nice enough to take some H U G E photos of my rig in action. He also caught one of the other guys. Both are VEKTAs. Mine is the one with the red bead lock rings. The other one has a 65cc engine and it is insanely powerful.
|
# ? Apr 22, 2018 06:34 |
|
InitialDave posted:
There's a couple of British ex-pats at my club and whenever one of the Aussie drivers pass them their throttle and wheel controller to test out the car, you could see the Brit drivers almost having a fit.
|
# ? Apr 23, 2018 03:04 |
|
The second amendment is really about our right to pistol grip transmitters.
|
# ? Apr 23, 2018 03:13 |
|
$200 Granite 4x4 Brushed version + $89 Castle SCT combo. VROOM. Just remember to flip that gear upside down before you test run it.
|
# ? Apr 24, 2018 01:31 |
|
We're back at the parking lot
|
# ? Apr 24, 2018 02:11 |
|
Build night number two for my TA07 is over. Seven hours in, and it's on wheels, has a motor, and a steering servo. My friends car has all the carbon on it, and it's a lot stiffer. Both cars leave something on the table when it comes to torsional stiffness. At least when compared to say my FF03, or TC4.
|
# ? Apr 24, 2018 15:14 |
|
More question for a crawler beginner. What's going to break first on that thing? I'm assuming steering servo (what's a good 40x40x20 servo?). I got batteries and receiver for days, and I'll convert it to xt60. Am I missing anything?
|
# ? Apr 24, 2018 15:20 |
|
evil_bunnY posted:More question for a crawler beginner. What's going to break first on that thing? I'm assuming steering servo (what's a good 40x40x20 servo?). I got batteries and receiver for days, and I'll convert it to xt60. Am I missing anything? Servo will be the first. Depending on the servo you get you might need to use an external BEC (use the 10A Castle Creations unit). For reasonably priced good performing servos you have the Savox 1210-SG, the Hitec 7954 or the Hitec 7950TH. Get a better servo horn, either the optional Axial or Vanquish that matches your aftermarket servo (Futaba/Savox is 25T, Hitec is 24T). Some like brushless motors, some do not. I like brushless and would say get the new Castle Mamba X and a 4 pole sensored motor. The Castle Slate line would be great. Maybe some better links depending on what kit you end up with. Different tires will make all the difference in the world. Since you are getting different tires you might as well get some two stage foam inserts and then some Vanquish bead lock rings and then.....
|
# ? Apr 24, 2018 16:23 |
|
Thanks for the servo recs. The rest will prob come as more stuff breaks. Does anyone make a good servo that’ll take 2s? That would simplify things a lot.
|
# ? Apr 24, 2018 23:02 |
|
All three servos I suggested are 2S/lipo compatible.
|
# ? Apr 25, 2018 00:14 |
|
Good news guys, a ARRMA Granite with a Castle SCT brushless system in it can nail a lawnmower tire at 45mph, go flying off the other direction, land, and suffer only a few loose teeth in the servo saver and a cracked front bumper.
|
# ? Apr 25, 2018 22:27 |
|
Somewhat Heroic posted:All three servos I suggested are 2S/lipo compatible.
|
# ? Apr 26, 2018 09:58 |
|
oops.
|
# ? May 6, 2018 23:23 |
|
I'm setting up the scx10.2 and here are some brain dumps: let's just say the default radio is rather limiting when you're used to OpenTX and CNC hall effect gimbals. I'm going to let the kid use my x10 and get them an X-lite if he gets into it (so I can harass him with my brushed quads). The ESC has a loving 20% deadband around 1500us. Easy to fix with curves but still laughable. I've got triple rates, throttle cut and throttle smoothing setup and it's actually a ball to drive around. The wheels are hilariously untrue, but that's not going to matter at the speeds we'll be seeing. The shell is nice, so are the lights (although the wire routing is meh). On a 4Ah pack it'll go basically forever, which is a nice change of pace when you're used to blowing through 1,8Ah 4s packs in under 3mn. I'm currently looking at stupid stuff to hook up to the 2 free channels I have left (probably emergency services beacons and a lightbar or 3). What's a good RC switch that'll handle a couple of amps at 2s? evil_bunnY fucked around with this message at 11:37 on May 12, 2018 |
# ? May 11, 2018 14:39 |
|
Well.. that was a great weekend of RC stuff. Friday, I spent the evening racing. It appears that I've been accepted by the locals. More or less a "you're not fast enough, here, how's to be faster". I got some advice on my lines, I was deeply overcooking a hairpin at the far end of the track. I got advice on how to setup the car, we threw my motor on a motor analyzer. Here's what we found: -The sticker on my motor was ~wrong~. I thought I had it set to 40deg timing, according to the motor analyzer, I was at 26deg. We got that set to 50deg. - The car was also up at something like 7 or 8mm of ride height. On black carpet, you want to be as close to 5mm as you can manage. My car is between 5.2 and 5.5 now. - We lowered the roll center up front, to encourage weight transfer on corner entry. - We tipped the rear shocks inboard, to also encourage weight transfer to the outside of the corner. - We set the front tie rod ends to the inner holes on the knuckles, to gain ackerman. The best time I got on "my" setup, was a 17ish second lap. Getting the motor sorted, and ride height set, got me to a 15.6. After suspension and steering geometry changes, the car is down to a 15.3. The fastest people at the track are high 13's. There's a solid second left in my current setup, if I could just drive well. I came in 6 of 7 racers running VTA Friday. I was told, independently, by three people, that "You're gonna need a better chassis, soon." I'm running a TC4 club racer. ESC News: Cheap ESCs have low powered BECs. I put in parallel to the the 1amp LDO reg, a 5amp LDO reg, on my Turnigy Multistar 80amp ESC. This got rid of most of the steering servo glitches, and the receiver isn't reporting brownouts anymore. To install that reg, I got some silicone servo extension wire, and ran the wires out under the power board. TRF201: The TRF201 got some new shock oil, I believe it's stiffer than it was initially setup. I haven't had a chance to take it to the off road track yet. But, I can say that servicing aeration shocks is a whole lot more fun than bladder shocks.
|
# ? May 14, 2018 17:37 |
|
I love me the TC3/TC4, but it's an ancient car with a very heavy and draggy drivetrain at this point. If you're trying to keep your costs down you can probably snag a used TC6 or 7 for cheap. Or a few year old version of whatever chassis the Cool Kids in your club run. I'm too lazy to check anything but Associated.
|
# ? May 15, 2018 03:43 |
|
I have no particular love of the TC4. The tub just doesn't keep it's shape well when traction is so high that you're fighting rollovers even with VTA tires. I was doing some research on TC4 setups, and I found a race winning car, that the driver had knocked 3mm off the edges of the tub, and cut out the arms off the corner support brackets. My brain screamed "Whaaaa?" Why do you think the TC4's drivetrain is heavy, or draggy? It's got a ball diff out back, and a spool up front. Both of those are going to have a smaller moment of inertia, and total weight than any modern gear diff. The driveshaft isn't as light as a belt, but it's small diameter, and spools up with very very little energy. I believe Awesomatix still sells a gear drive car, and Tamiya is also right up there. Oh yeah, take a look at this thing: https://kfrusa.com/products/kaizen-tc4-conversion-kit A "modern carbon chassis" for the TC4 drivetrain. The TC4 even has less bearings on in the drivetrain. My TA07 has four large bearings, and eight small bearings. About half of the small bearings are guides, and may, or may not contact the belt all the time, but when they do, they're spinning ~really damned fast~ due to belt surface speeds. At least when compared to shaft support bearings. Most belt drive cars, have one extra belt interface too. There's a lot of reasons that modern belt drive cars "are the thing". I don't think drivetrain weight is a big matter. And in the case of my TA07, and TC4, I don't have DCJ's on the front end. Speaking of belt drive cars. My buddy and I did some digging, and found the OEM for the softer, kevlar and polyurethane belts. A set for my TA07 is waiting for me, as soon as I can be bothered to drive up and pick them up from Misumi. That reminds me.. i'm supposed to try to find some left hand thread forming taps. I've been accepted by the locals. It was hinted that there may be an X-ray showing up for me, at a very very favorable price. We shall see how that turns out. :-)
|
# ? May 15, 2018 15:42 |
|
Post that OEM, friend
|
# ? May 15, 2018 18:01 |
|
kuffs posted:Post that OEM, friend Give me a couple days, I want to make sure I found the right stuff.
|
# ? May 15, 2018 18:44 |
|
Nerobro posted:I have no particular love of the TC4. The tub just doesn't keep it's shape well when traction is so high that you're fighting rollovers even with VTA tires. I was doing some research on TC4 setups, and I found a race winning car, that the driver had knocked 3mm off the edges of the tub, and cut out the arms off the corner support brackets. My brain screamed "Whaaaa?" Shaft drive RC cars usually have more friction in the drivetrain compared to belt cars due to the extra gears and also the weight of the shaft. However they are more efficient with getting power down compared to belts, as they don't have the drivetrain slack that the belts give you. You have to remember the TC4 is well over 10 years old and RC chassis engineering has changed hugely since then. Back then you wanted the chassis as stiff as possible, these days people want chassis to be softer and allow flex. I have just brought a new Xray T4 2018 TC as Mini has died in the arse at my track. Xray in Australia has great support from the distributor and their drivers, which is bizarre for a supplier, as most of them don't give a poo poo unless the driver themselves are importing the brand.
|
# ? May 16, 2018 01:44 |
|
You Am I posted:You have to remember the TC4 is well over 10 years old and RC chassis engineering has changed hugely since then. Back then you wanted the chassis as stiff as possible, these days people want chassis to be softer and allow flex. For what it's worth, I'm basing this off of my own personal experience... which is with two very high mileage 1999-vintage TC3s. Maybe the TC4 solved more of the problems that the TC3 had, but I always thought the two were very similar overall. I love them, but they've just got nothing on the TC6/7.
|
# ? May 16, 2018 02:19 |
|
To start off, I'm not particularly defending the TC4, I bought it because it would be a good entry to VTA. Consider this more of a "what's really getting better with cars" discussion. You Am I posted:Shaft drive RC cars usually have more friction in the drivetrain compared to belt cars due to the extra gears and also the weight of the shaft. However they are more efficient with getting power down compared to belts, as they don't have the drivetrain slack that the belts give you. Sadly, I don't own enough cars to do a real survey. And two of my cars are basher quality. (The TT01e and TT02b) But I believe that gear drive, versus belt drive is a wash, at least in high quality installations. Gear interfaces are ~usually~ 98-99% efficient. So are belt interfaces. Belts have more variability, as tension factors heavily in that equation, as does belt material. However, gear drive cars, apply torque to the chassis in ways that belts don't, so there are some real advantages to belts, in the handling department. Also worth mention, is belts are narrower, and depending on chassis design can let you move battery, servo, and radio gear closer to the center of the car. The TC4 really is ancient. But.. what's changed? Chassis flex tuning has become "more recognized". Chassis are being built to allow them to roll more without dragging. They're both stiffer, and softer, depending on who's running where. CG has become a much more important point of contention, so shock towers are dropping, shock lengths are shortening, and everyone is running swaybars. People running carpet are running aluminum lower chassis to get the cars even stiffer. And to keep the CG down. ... I wonder if anyone has tried doing a custom layup to get a more rigid lower plate than aluminum. Everything I've seen just uses a typical plate carbon with the usual 1x1 weave. Some unidirectional stuff layed up in a careful schedule might be stiffer than aluminum. Also on the subject of "stiff chassis". I keep thinking that people are compensating for poor suspension tuning, when they start softening things up. There's at least one very competitive person at my track who runs the stiffest car he can, then spends his time with shocks and suspension geometry. He isn't slow. What's the "big thing" that hit between the TC4 and today? I'd point out Gizmo and Awesomatix going to the double A arm setups as being a big point. By getting hub stability away from the lower control arm, they're getting better wheel control. Though it's a few years late, DCJ's are critical to fast cars now. I'd call it a "big thing" but other cars have had it in the past, but full control over suspension geometry, seems to be the rule these days. Between Tamiya has their mounting blocks, X-Ray and Team Associated have their pivot pin pills. When I was last seriously in R/C having ~any~ options for things like antisquat, rear toe, and roll center were a big deal. Now, if you can't dial in pro-squat, and have seven levels of roll center before breaking out shims for the tops of the knuckles you're not driving a fast car. I was about to say something about the inability to change that on the TC4... but maybe you can shim the axle blocks? I haven't tried that. it's still not as slick as the pills you find on the more modern cars. IOwnCalculus posted:For what it's worth, I'm basing this off of my own personal experience... which is with two very high mileage 1999-vintage TC3s. Maybe the TC4 solved more of the problems that the TC3 had, but I always thought the two were very similar overall. Wasn't the big thing between the 3 and 4, mostly the steering rack? The TC4 got a different set of shock mounts too. Beyond that, the cars were mostly the same. If I were to guess, the next "step" in r/c tech, is going to double arms, and still shorter shocks.
|
# ? May 16, 2018 15:54 |
|
The TC3 steering rack is indeed hot garbage, no argument there. The 6/7 linkage is much nicer but it sucks rear end to swap a servo. Granted, I learned on 1/12 pan cars, and nothing is easier to change a servo on than a pan car. The other thing with the 3/4 versus the 6/7 - and even again from the 6/7 to the competition - is the amount of slop in the suspension. Even with brand new components there's a good deal of slack in the TC3 arms. The 6/7 have less, but every competing brand car I've seen at the track has nearly none.
|
# ? May 16, 2018 16:29 |
|
As you mentioned Nerobro, there has been big changes to suspension over the past 10 years, including smaller shocks for lower cg, huge amount of work into chassis tuning through flex. I race primarily asphalt outdoors, there aren't many indoor tracks in Australia, and there's only one big international event a year in Australia where there's a chance of carpet racing. On asphalt, flex is everything. There's a driver at my track who runs his own carbon fibre engineering business ( http://bezerk.com.au/shop/ ) who is manufacturing vertical top decks to get adjustable flex for outdoor on road racers. Steering setups have changed a bit over the years, companies using floating servo holders, some using full floating steering setups. Smaller shocks seem to rule most touring cars these days, with the exception of companies like Awesomatix and Serpent. Just check out the arrangement they have for shocks, it is a engineers wet dream. Drive trains themselves have changed a bit, including the use of DCJ axles on the front of the car instead of universals so you don't get the axle chatter with a spool and also get the benefit of more steering. Diffs have gone in and out of fashion. When I started most touring cars were using front one way diffs (and on some chassis centre one ways for the front pulley) and ball diffs at the rear. These days spools seem to rule the front (with some exceptions like Mini or some people using putty filled oil gear diffs) with oil filled gear diffs ruling the rear. And don't get me started on moving from NIMH batteries and brushed motors to Lipo batteries and brushless motors.
|
# ? May 17, 2018 00:13 |
|
Just finished this:
|
# ? May 17, 2018 08:35 |
|
Adorable
|
# ? May 17, 2018 13:02 |
|
evil_bunnY posted:an scx10 II is a perfectly acceptable first crawler for a 4,5 YO right? Right. Asking for a friend. Honestly, The RedCat Racing Everest Gen 7 Sport @ $200 RTR I think is the best way to get started IMO. I either currently own, or have owned almost every crawler, and scale truck on the market, and I don't think you can beat it for the money.
|
# ? May 18, 2018 05:27 |
|
krushgroove posted:Yikes! Glad you got the battery out quick enough, otherwise all your electronics (and car) would have gone up. I have that FJ40 as well, I converted mine to the RC4WD 2 speed trans, installed LED lights, and swapped the tires to Swampers, as the stocks were silly small. Super top heavy rig, but fun to drive being so scale!
|
# ? May 18, 2018 06:37 |
|
Budget Monty posted:Honestly, The RedCat Racing Everest Gen 7 Sport @ $200 RTR I think is the best way to get started IMO. I either currently own, or have owned almost every crawler, and scale truck on the market, and I don't think you can beat it for the money. If I were reasonably price-conscious the gen7 would mosdef be a better match. But the scx is red and can be made into a fire vehicle of sorts evil_bunnY fucked around with this message at 16:14 on May 18, 2018 |
# ? May 18, 2018 11:16 |
|
evil_bunnY posted:...If I were reasonably price-conscious.... SCREW THAT so I am build a 1/5 FG EVO onroad car right now and behold it. Behold it!
|
# ? May 18, 2018 16:59 |
|
There's nothing "somewhat" heroic about that. 4 wheel disks? I want that in my touring cars...
|
# ? May 18, 2018 17:04 |
|
I love those big onroad cars. Too bad there’s no tracks around here for them.
|
# ? May 18, 2018 17:06 |
|
Nerobro posted:4 wheel disks? I want that in my touring cars... kuffs posted:I love those big onroad cars. Too bad theres no tracks around here for them. Just recently some dude went and built a permanent racetrack at Fontana Raceway (yes that Fontana) in California and the place is a masterpiece: https://www.facebook.com/steelcityrcspeedway/ There is a race happening later this summer and I might try to attend.
|
# ? May 18, 2018 17:30 |
|
|
# ? May 27, 2024 03:22 |
|
evil_bunnY posted:I’ve already bought and setup the scx. If he likes it I’m getting a trx4 sunset bronco for myself and a radio for the kid. You won't be disappointed with the TRX-4! It is probably my favorite of my trail trucks. It turns tighter than anything else I have when the diffs are unlocked, it's pretty sweet. I have mine on a Spektrum DX5R, so I have completely independent diff lock controls now, it's awesome!
|
# ? May 19, 2018 04:57 |