Mad Ax

Members
  • Content Count

    3161
  • Joined

  • Last visited

Community Reputation

1121 Excellent

About Mad Ax

  • Rank
    Advanced Member

Contact Methods

  • ICQ 0

Profile Information

  • Location Lurking among the gothic shadows of Bath
  • Interests Streetfighters, motorbikes, fiction writing

Recent Profile Visitors

6781 profile views
  1. Mad Ax

    Tamiya MFC 01 ,issue?

    Or you can give it full throttle and dump the right stick to do a burnout
  2. Mad Ax

    Rally car - TB01 or TT02 Type S?

    The only proper rally-spec chassis I have is an old TB01. It has the dust cover, so it doesn't get any gravel in the tub. I think it also has TB Evo arms, and it took me an age to figure out why I couldn't get replacement UJs to fit after mine destructed. Ground clearance is good with long shocks and the TB wasn't a bargain basement chassis when it was new. It's heavy compared to a TT02 but heavy is good, heavy is reliable. I keep meaning to build my NIB XV-01T into rally spec but since nobody ever goes rallying any more there doesn't seem much point in rushing it, especially as I haven't found a readily-available rally shell that I really like yet (with the possible exception of the new Quattro).
  3. Mad Ax

    Tamiya MFC 01 ,issue?

    +1 for Teri's vids, I watch them all the time. Teri is a regular at my closest club. On that subject - @Gazzalene where are you based, and do you have a truck club near you? If you're still not having any joy it might be worth popping along. There's bound to be someone there who knows Spektrum and MFC well enough to help you get it working. You'll find driving on a layout is way more fun than driving around your lounge, too
  4. Tyre glue is a very thin CA glue. Be careful with it, it's easy to get it absolutely everywhere. I use Tamiya's thin cement for light clusters but I must admit I don't have much luck, they tend to fall off. I have heard some people say that regular CA glues give off a vapour that fogs the lenses. Whatever you use be careful with it and start with small amounts, if you get it onto the lens part it will ruin it. I have a trick that involves using double-sided tape to stick the lens to my finger while I add the glue and press it into place. It's easier than trying to hold it between two fingers. The glue will wick between finger and lens if you're not careful. Once you've pressed the lens into place you can then hold it down with another finger while you pry your skin away from the tape. Take your time
  5. Mad Ax

    Tamiya MFC 01 ,issue?

    I don't use a Spektrum radio so I can't help exactly. I'm pretty sure on my trucks all channels are in the "normal" position (i.e. not reversed) - I don't see why Spektrum should be different but maybe someone with a working Spektrum setup can clarify. As far as I know you shouldn't need to use any aero-specific switches but it's worth checking the radio configuration. If it's a specific aero handset then it might be configured to limit or disable channel movements based on the settings of your switches and knobs. I say this because I recently started using a Turnigy 9X - I configured the 3 rotary knobs to output to channels 5, 6 and 7, but I found that setting one knob would change the value output by a different knob. The radio was doing some kind of aero-specific trimming of the channels because it assumed I had those channels hooked up to the normal aero control surfaces. The 9X lets me change between aeroplane, helicopter and glider modes - I had to put it to glider mode to get the knobs doing what I wanted it to do. So - with that in mind - make sure that none of your switches are interfering with the output of channels 1-4 because the MFC needs to receive 100% deflection on all channels to operate normally (drive, shift gears, steer) or 125% deflection on all channels (to operate special functions like turning on lights, activating the support legs and remote engine start / stop). If you've got a trim knob or switch which is causing one of the channels to only output 50% or something, that will cause you problems. Re: channel reverse - if the truck is driving forwards and backwards correctly, if the gears are shifting (or at least trying to shift) correctly, and if the steering is working the right way around, your channels are set up the right way. AFAIK the MFC isn't clever enough to reverse-calibrate the servo outputs. However, it is clever enough to reverse calibrate the indicator lights - I know because I accidentally calibrated right when I should have gone left and left when I should have gone right, and the indicator lights ended up the wrong way around. If in doubt, make sure your Tx is in 100% deflection mode and go through the MFC calibration again and check that basic stuff light steering and gears work properly. Note that on the MFC-03 the 'start motor' command is right stick fully down (in 100% mode). Less than 100% down and it'll do a false start. If it starts up and drives around normally then you're most of the way there.
  6. Mad Ax

    How do clamping hex's work?

    I bought a huge load of cheap ones a few years back before discovering how they don't actually clamp without ruining the screw head. Now I put them in the bench vice and slowly wind them in to bend them into shape, then press them onto the axle and tighten the screw to stop them flexing out again. If I have to remove them, I undo the screw and use a small flat-bladed screwdriver to open them out.
  7. Mad Ax

    Tamiya MFC 01 ,issue?

    Have you managed to get any of the functions working yet? e.g. turning on head lights and/or hazards? If that works then the remote engine start/stop should work too. With the handset in 125% mode (however you've set that up) move the left stick fully to the right and the right stick fully to the bottom. Engine should shut down. Make sure you've configured the 125% mode to apply to all 4 channels and not just the right vertical channel
  8. Mad Ax

    Pacific Green Grand Hauler

    I went to a local full-size truck show last year. Being in England it was mostly Euro trucks but there were a couple of Big Petes parked up near the entrance - probably show trucks and big boy's toys more than working rigs. Not for the first time, I found myself thinking "dang, I was born in the wrong country in the wrong decade..." I was chatting to someone who owned a Scania V8 rig, he said he got through £100 worth of diesel across the weekend, just revving it up for the crowd. I'm not sure the owner-operator lifestyle is as romantic as it sounds, especially in Britain...
  9. Mad Ax

    favorite wet-weather model?

    One of the reasons I love scale crawling is it's just as much fun in the rain as it is in the dry. Living in southwest England, rain is never far away at any time of year and it's very easy for a weekend of racing to be ruined by the last-minute arrival of a 3-day downpour. Case in point - last summer we had a 30+ degree heatwave that lasted several weeks. On the day of the Iconic Revival, I put up my awning in 30 degree temperatures. A few minutes after the awning went up the clouds came over, temps plummeted and a storm blew in that lasted for the entirety of the event. We raced anyway and we had a laugh, but the track got sodden, we lost racing time due to having to brush the water away and wait for the worst of the rain to pass. My Top Force and Bear Hawk survived the worst of the weather, no electrics were harmed and an afternoon in front of the sink got the worst of the dirt off. The astro track we raced on has sand as a substrate and it gets into everything when it rains. I think the same was taken from the shore because when it rains at that track it smells like the sea. The sand leaves a greasy green residue on the cars which takes ages to get off, and steel goes rusty pretty quick. It's a good idea to clean up the cars and put on some 3-in-1 oil as soon as possible after racing. Last autumn we had a local crawler meet in a disused quarry. I invited two mates and let them borrow my spare rigs. It poured solid all day. Three of us fit nicely in my camper awning for servicing and repairs on the rigs, but the only way to enjoy the trails was to button up and get out in the wet. An hour into the first course our sleeves were soaked through. It rained so hard the water was running into my waterproof jacket's pockets and down into my jeans. I had rising damp in my waterproof overtrousers and my boots let the water in after 2 hours. My Turnigy 6ch transmitter let the water in and gave up around midday, so we opened it up and left it to dry while I cooked bacon and egg rolls in the camper. After lunch it had dried out enough to work again, although the Turnigy receiver switch attached to the LED lights has shorted and is now on all the time. At the end of it all, it was one of the best days out I've had in as long as I can remember. All three of us got soaked through and covered in mud, the rigs were so filthy I hosed them down in the yard rather than take them to the house, and we rounded off the day with a swift drink by the fire in a local pub. At heart I'm an English Summer Man - I don't really like winter, I don't like the cold and I don't like the rain, I like blue skies and soft breezes and dusty roads and hot days that fade slowly into long, balmy evenings - but I always think you never appreciate a pint of ale in a warm comfortable chair as much as you do when you've come in a long day outside in the cold and the wet. Once I went to a bash on an outdoor tarmac track and as usual the heavens opened shortly after I got there. One corner got totally submerged but we carried on bashing anyway. I was running my TT02D and I lost control and went right into the drink. The car was submerged up to the windows. It ran fine for the rest of the day but the following time I switched it on the Nosram Evil brushless ESC wouldn't work. Since they were known for being utter garbage and I only paid £15 for it second-hand a few years previous I wasn't too upset to see it go My pre-wet preparation: Blue-tac around the receiver plugs keeps the worst of the water out. I've submerged ORX receivers like this and they've not absorbed a drop of moisture and worked perfectly fine after despite not being waterproof. My post-wet routine: Partial strip-and-clean in the kitchen sink if it's really muddy or a race car, spray body and chassis off with cold water if it's a scale rig. Oil any external moving parts with 3-in-1 oil to prevent rust. I avoid WD-40 as it's a solvent and can dissolve the grease inside sealed bearings. If any electrics were submerged or show signs of water or moisture inside (or have stopped working), remove them and place them somewhere warm and dry.
  10. Mad Ax

    Tamiya MFC 01 ,issue?

    Last time I was at the Bournemouth truck meet, one of the guys was sweeping up the gravel that he had been loading into 1:14 tipper trailers with his 1:14 excavator. I told him he needs to get a fleet of 1:14 scale minimum wage yard workers to do that. I've been RC trucking for about 3 years now, and although I have 2 running rigs, 1 build in progress, 1 NIB and 4 trailers, I still consider myself very much a novice with lots more to learn, about trucking in general and RC trucking in particular. I know the MFCs because I've been using them since I started but I doubt I'll buy any more for my new rigs. If my Arduino MFC works out I'll port all my rigs to that.
  11. Mad Ax

    Custom MFC using Arduino

    Another update - bit of a long and technical one, I'm afraid, but I will include a summary at the end. So as I mentioned elsewhere, I got the system hooked up on the Drag King a few days ago but I was having some trouble with a glitchy steering servo. I actually hooked up the radio to the servo without the Arduino and still had some glitching problems - I tried a different servo, different channels and would have tried a different Rx but I don't have anything that works on the 9X's protocol. I figured the issue must be in the Tx/Rx itself so I conveniently decided to leave it for later. I did read in a few places that the 9X can be prone to interference and I was running a video baby monitor at the time, which is famous for glitching everything in the vicinity, so I didn't worry over much. Last night I brought the whole assembly into the studio and plugged it into the laptop to see what was going on. This time where was no baby monitor but the glitching was horrendous. I wouldn't have wanted to drive it. When operating the steering the servo would jump between positions and never sit still when centred. I'm using the PPM port on the Rx, so I was able to hook up a second servo to ch1 on the Rx to see if the glitch was being introduced by the Arduino or if it was on the channel all along. The result: the servo on the Rx worked fine. I tried swapping the servos over again and tried different channels but basically, however I hooked it up, I was getting glitching effects through the Arduino that I wasn't getting directly from the Rx. I checked and checked again that the wiring was hooked up correctly, that the earths were good and that the servo was getting plenty of juice from the LiPo. Everything looked just fine. Then I noticed something really odd. As a reminder - I'm using the servo.h Arduino library to control the servo, and it needs to be fed a value (in degrees) of between 0 and 180 to set the servo to the specified angle. I've got a map() taking place to turn the incoming PPM values for steering and throttle channels into a servo position, and I'm outputting said angle to the servo. Here's the odd thing: I had the Arduino Serial Monitor set up to list the input values coming form the receiver and the angle values going out, and the outgoing values were not changing. Yet, the servo was glitching. So, according to my code, I was outputting a constant 90 degrees into the servo, and yet the servo would happily sit there, at idle, twitching twice per second. I did some searching online and found various threads reporting this when using servo.h and some that alluded to an issue with watchdog. I had to look that up, but watchdog is essentially something runs on the Arduino firmware and checks that it hasn't crashed. I think it's designed to reboot the Arduino if it stops working so that an automated application will not fail if the controller stops responding. It polls the interrupts every 500ms, which coincides nicely with my glitching. Anyhoo - various attempts to disable watchdog made no appreciable difference. Disabling timer 0 caused my PPM inputs to stop working. Around this time I was ready to throw my teddies out the pram and walk away, but I was reading elsewhere about config for servo.h and I decided to play around with settings. Hold this thought. Another issue I've had is that I get way more servo throw through the Arduino than I do through the Rx, so the extend that the servo actually twists the axle on the leaf springs at full lock. I had planned to fine-tune the endpoints later but something jumped out at me while I was reading: I was mapping values of 1000 to 2000 to values of 0 to 180, but the default configuration for servo.h is to assume 0 is ~500 and 180 is ~2500. That's actually beyond the range of most servos. There's an optional overload on the servo init method that sets the endpoints. Once I'd set the endpoints to 1000 and 2000, the glitching was greatly reduced. In fact whatever interference seemed to be causing the 500ms twitch was gone. As I played more with the Arduino, I began to notice more things. Notably, the servo would never move smoothly as I moved the stick - it would jump between positions. Comparing input to output in the serial monitor I could see I was losing a lot of resolution by converting from PPM to degrees, so I got rid of the PPM-to-degree map entirely and replaced servo.write() with servo.writeMicroseconds(). That way I was writing out exactly what was coming in (minus some deadzone and mode change stuff). Result: move smoother servo operation. There was still some jumping going on, but much less than before. But there's more to come: I also noticed I'd put in an arbitrary delay of 20ms in the main loop. When writing for most platforms it's good practice to throttle any loop with a delay to prevent it from hogging all the system resources, but as the Arduino is only a basic controller and isn't multithreaded I figured maybe this wasn't necessary. Indeed - if I increased the delay to 50ms or 200ms the jumping in the servo got noticeable worse. Of course it did! The longer the delay in loops, the lower the resolution in converting a smooth input signal to an output. By removing the delay altogether I was able to increase the resolution just slightly better than with a 20ms delay. I might have to do some debug logging to work out exactly how many loops per second I can achieve because it's not perfect. I can only guess that, at this point, I have reached the limits of what I can do with an Arduino: it's only designed for basic applications and it's doing quite a lot of unit processing between reading the PPM input and sending outputs to various pins. The PPM library I'm using is a closed box and I don't know if there is anything in it that could affect performance. Anyway - by logging the loop speed I might be able to do some performance tuning and speed up the loop for better resolution. And again - I still have not yet looked into the audio at all. I was intending to use the current MFC code to issue a series of commands over serial that a second Arduino could read as instructions to play audio - as in a master/slave config. I'm now wondering if I should duplicate my current code on the second MFC but replace the servo and light code with audio code. That would reduce any additional processing I need to do on the master Arduino. The other alternative is that I port the code to Python and see if I get better performance with a Raspberry Pi or something else that has more power. They're a bit more expensive but not prohibitively so. Yet it could be that there's no performance problem at all and the glitch is elsewhere, and I'll find it if I keep digging and debugging... Another thought I had is that the glitching probably looks a lot worse than it is because the axles are lifted off the ground by old TLT tyres and the stock setup has so much play that the wheels visibly rock with every movement. Once down on the ground the problem will hopefully not be so noticeable. Summary Hooked up the latest version of the code to the Drag King and had some servo glitching. Not a fault with radio or servo. Vastly improved by transmitting PPM values direct instead of converting to degrees for the servo library but still having resolution issues that appear to be caused by slow performance. Play in steering makes it look a lot worse than it probably is. Still unsure when I'll do an on-the-ground test drive as I haven't set up any wiring that allows the Arduino to be mounted safely off the ground and away from bare metal.
  12. Mad Ax

    Pacific Green Grand Hauler

    Stunning work
  13. Mad Ax

    Tamiya MFC 01 ,issue?

    The MFC-03 had some extra features, but I use both and I find them both equally easy to use. I don't really miss the additional MFC-03 features when I'm just driving on the layout. The main difference obviously is the sound. I remember being told that the MFC-01 engine sound was recorded from a Cat engine whereas the MFC-03 is recorded from a European 6-cylinder engine. The 03 sounds better in European rigs and the 01 has that classic American sound. Sadly the 01 doesn't have a traditional Detroit Diesel and the 03 doesn't have a Scania V8 sound - IMO that would make them almost perfect! Other differences, off the top of my head: MFC-01 starts the motor sound and enables drive as soon as the Tx is switched on. MFC-03 does a pre-start sound when switched on but does not start the engine sound or enable drive - you must command it to start via the Tx before you can drive off. When Tx is switched off, the MFC-01 will shut off the engine sound and sit idle. The MFC-03 will shut off the engine and play the annoying "Tamiya No Radio" bleep effect. This isn't a problem since you can shut down the motor via a Tx command on both MFCs and leave them idle. Speaking of which - to start and stop the engine on the MFC-01 is not well documented. Slide the gearchange trim all the way to the right, slide the right hand vertical trim all the way to the top, then move the left stick fully right and the right stick fully up. The motor sound will shut off and the truck will go into 'park' mode where it can't be driven. Lights will still work (IIRC it plays a 'lights on' warning bleep). Repeat the process to turn the truck back on. Do it with the lights on and see them flicker as you start - that's a very cool effect. The MFC-03 has the same feature except you need to move the right stick vertical trim all the way down and pull it all the way back to turn the ignition on/off, and you then have to pull the right stick fully back a second time to crank the motor and start the truck. (If you only pull the stick part-way back you get a false start, which is kinda cool). The '01 doesn't have the separate start feature - the truck is either started or stopped. The MFC-03 has a 'virtual clutch' feature. If you pull the right stick all the way back while the engine is started, you can rev the engine with the left stick without the truck moving. It's a daft but cool feature. What is cooler is that you can pull the right stick back, push the left stick all the way forwards to redline the engine, then drop the right stick back to centre to dump the clutch. The electric motor will go immediately to full speed and the truck will launch off the line quickly. On some surfaces you can spin the back wheels that way. To be honest, cool though this feature is, it's not one you'll use a lot on a busy layout. The truck can fire off very quickly and there's a big risk of hitting someone else's rig and doing some expensive damage... The MFC-03 also has a gearbox position learning feature. When you 'teach' the MFC you tell it were the select positions are on your Tx and it then does very slick gearchanges by toggling those three positions on the servo. The MFC-01 doesn't do this - it just transmits whatever it gets from your gear stick on the Tx into the servo. It's not a big deal - if you're using a shift gate on your Tx then you won't have problems, just don't drive around with the stick at mid-point between the gates. Using a Spektrum radio should be fine - there are tutorials on Youtube on how to set it up. I've never done this but I know people using Spektrum on the MFCs. On the FlySky and similar radios you have to set up an A/B switch that changes the endpoints on all your channels from 100% to 115% or something, then when you want to just drive you run on A mode, and when you want to input commands such as lights on, engine stop etc., you flick the switch to B mode, input the command with the sticks, then switch back to A mode to carry on driving. I've always assumed the Spektrum configuration is the same but never looked at it as I'm too poor for Spektrum radios. FWIW I buy a cheap Tx for each new rig so I can have them all running at once. If you're not 100% taken with the MFC then look into Beier modules. You can start with a basic light, sound and speed control unit and add more features are cash allows. https://astecmodels.co.uk/ sells them and the owner is super-helpful if you have any questions before you purchase. I hope that helps
  14. Mad Ax

    Tamiya euro, gearbox linkage help

    I'm sitting in front of my rigs right now and both are right up against the circlip. Both are running Tamiya MFUs (MFU-01 and MFU-03) and they shift with no problems.
  15. Mad Ax

    Racing a Novafox - what's necessary?

    Any 2.2 buggy wheel is permitted, so I can fit adaptors. I'll probably use my favourite HPI Super Star wheels on the back (technically they are touring car wheels but hey are hex drive 2.2s and the right width for buggy tyres and I guess a Tamiya stardish or similar on the front. I've never found a good 2.2 that accurately matches the Super Star style.