Keracticus Pots

Finding somewhere to do speed runs >50 mph is difficult. Manhole covers, road repairs & kerbs are not your friend. KP

For all you air-cooled aficionados out there. KP

A really interesting thread. Over the years I've been on and off with RCs. Sometimes going for years with no interest. Coming back most recently I liked the idea of an anniversary Porsche. I was amazed at what these were going for and wasn't prepared to pay that much. I settled on a TT02 RSR. The whole market around the 45th I found quite disappointing. Driven in part by FOMO, speculators and I'm sure other factors. The whole spares situation is rubbish. Break something on your new BBX and you have no chance of getting spares. This drives an element of demand for kits that should be met by adequate spares supply. I think it's a shame you can't simply look in Tamiya's current catalog in any given year and go and buy what takes your fancy. This whole FOMO isn't just Tamiya or RCs - just look at the MoonSwatch. It's across the board with many consumer products and as others have said, demand is driven these days by a whole bunch of new factors that didn't exist 20 or so years ago. Now (IMO) the 50th anniversary is going to be something really special and I'm already caught up in the whole FOMO! KP

I started a build thread but I've been pretty rubbish at keeping it up to date. I'll have to update it with where I've got to - I've tried a gyro and multiple servos. KP

I'm on a similar journey - trying to get a TT-02 fast. I've only got to 45mph with 64T spur, 30T pinion, 4600kv Robitronic on 2S. Now play around with other cheap high kv motors on 2S without spending Castle money! Biggest problem now is going straight. The old set up would do 45mph straight as an arrow. I cant get my new set up to even drive straight. Good luck. KP

This photo shows the sacrificial under tray that has to deal with the road above has been properly sacrificed to the RC gods! KP

Photo of the car post run covered in dust and grime. In the photo you can see the two temp sensors, the gyro and the SkyRC GPS mounted on the upper chassis plate. The next photos show the road I'm running on - up to the usual standards of UK roads. But on the plus side, on a Sunday (or Bank Holiday Monday) its pretty much traffic free, it doesn't have much of a crown to it and there are no cats eyes. KP

This has been a bit an on and off project but it's time for an update. I recently treated myself to a new radio - a SkyRC Noble NB 4. This is a feature packed radio at a mid range price. One of the features is telemetry from the car back to the transmitter. A range of sensors are available to measure voltage, temperature, altitude and rpm. I fitted a couple of temperature sensors to the motor and ESC. Now I can see real time motor and ESC temps and can set up some max temp alarms. For the power system and gear ratios I've currently been playing with temperatures were never really going to be a problem but I'm an Engineer and you can never have too much data! Another feature of the new radio is the ability to set the "Channel Speed". EG you can programme it such that if you rapidly pull full trigger, 0 to max ramps up over a user defined time. This will be more useful when running bigger power systems where a having a smooth input of throttle is key to minimising wheelspin, current spikes and voltage sag. Combined with user defined throttle curves and throttle dead zones this gives a lot of flexibility. Another area I've been playing with is getting the car to track straight. The car is set up with ball raced steering linkages, 3 deg of rear toe in and about 1 to 2 deg of front toe out. I had trouble trimming the car, it seemed to wander around neutral. To cut a long story short, I've tried 3 servos and replaced the servo saver with an alloy servo horn. The earlier servos I was using had more play/backlash around the neutral point. Combined with the mechanical nature of the backlash will be the accuracy of the sensors in the servo needed to maintain a commanded position both statically with no load and under load in use. I've ended up with a servo and set up that's not too bad. But it may just be I'm gaining experience at 40+ mph. As a slight aside, most will appreciate the specs for servos focus on torque values and angular speed. I haven't found any specs that detail either angular accuracy or some sort of measure of backlash. I've been playing with cheapish servos and I expect that some of the higher priced brands are designed and built with tighter tolerances. Steering gyros. There seem to be mixed views on steering gyros for speed running, ranging from "gyros are cheating" to "gyros are essential". My only experience of a gyro was recently with a drag slash. Box stock, cold tyres, full throttle, no gyro it was all over the place. With the gyro it was rock solid and straight as an arrow - I was amazed. So I wanted to try one. I fitted a SkyRC gyro. This was set up with the gyro gain adjustable on the fly using a third channel. I'm still on the fence with the gyro but it's fun to experiment with! The speeds I've currently got to are nothing to get excited about:- 45mph, 30T pinion, 64T spur, 2S CHNL 5600MAh 120C, Robitronic Razer Ten Combo with 4600kv motor & 60A ESC. Next step is to see what combinations of 31T, 32T pinions and 63T spur will fit under the gear cover and then fit a 4.5R Speed Passion motor that was going cheap at Modelsport. KP

Still trying to go fast! Time for a spur change - and what a PITA that is on a TT-02 with a top deck / chassis brace fitted. KP

Backing into the scenery sounds like a proper 911 accident! Glad you got it fixed. KP

Thought I'd try something different. Roads were finally dry enough to have a test run with my new Drag Slash. KP

A second hand Rough Rider, so not strictly a kit that I built. Like a lot of others I built static models and lusted after the RC cars in the Tamiya catalogue. A friend had the original 312T Ferrari, I saw that and was hooked. After saving every penny from jobs and pocket money for months I bought the Rough Rider for £80. And we need pictures. It had already got a modified roof and relocated lights. If you look closely you can just about see the steel bumper my Dad fabricated. Happy days. KP

Today was finally good enough to attempt some painting. Even though I was only planning on one colour, the body didn't come with any window masks. So it took a bit of time to mask up the windows and lights. Judicious use of a hairdryer, a can of red and some smoke for the windows and lights and I'm pretty pleased with the result. Then the best bit - peeling off the protective film! Now on with some stickers. (Badge not yet stuck on) KP

The thinner stock bumper, the undertray and some standoffs. KP

First couple of runs were over Christmas. I was dying to run the car even though the road was not dry. With a 22 pinion / 68 spur, max speed was 30mph. With a 22 pinion / 64 spur max speed was 35mph. This was a bigger jump than expected which I'm putting down to a partially discharged battery for the 22/68 runs. These runs were done without the body and before I'd made an undertray. In the picture you can just see my 1:1 car. Unfortunately I managed to crash into it and rip off a rear corner. Particularly disappointing as the body and an undertray (the width of the body and wider than the track) may have reduced the damage. KP

And Boeing, and GS Yuasa all overseen by a government regulator.

This is the first time I'd fitted a body without pre-drilled mounting holes! Measure twice, cut once. I don't think I did a bad job with getting the body fore and aft position correct. The big problem was getting the body low enough. In the photo below you can see the front of the body on the bumper. The second problem was the body hitting the shock tower. It's a bit hard to see in the photo above but the part of the shock tower hitting was where the kit body mounts screw in. As I was using the forward mounts I decided to modify the shock tower - so out with the hacksaw. What can also be seen is where I reduced the height of the bumper mount. And also cut the bumper in half. This resulted in an acceptable body fit. The body I bought is a nominal 200mm wide body and it dwarfs the chassis with the 26mm wide foams. I realised I haven't actually got any shots of the body mounted once I'd finished. I'll get on with that tomorrow. KP

I've been a bit slow with posting updates. I got the car finished. Kit dampers with 800cst oil & kit springs. Kit bumper with forward body mounts vs the kit shock tower body mounts. This seemed like a good idea to reduce body flex at the front. Final hop up was some bolt on hexes. Next was the body. KP

I'd guess that the vast majority of the middle age demographic that own more than 2 or 3 Tamiya are driven by nostalgia and are coming back to RCs. This certainly applies to myself. A "pre-loved" Rough Rider as a kid. Second phase was 2003 - 2009 when the kids were younger and then on and off for the past few years. It's only recently I've embraced all aspects of the hobby - NIB, shelf queens & runners. I've always appreciated the collecting aspect of old stuff that includes NIB & shelf queens. But previously I couldn't really get my head round the idea of buying new releases to just stash away or build and not run. Now I've worked out for myself I like the building - not so much the bodies - my skills are lower than my standards! So I'm going to end with more cars than I can sensibly run on a regular basis. So in summary, if you have the space and disposable income, keep them NIB, build and shelf them to your hearts content. It doesn't matter if you don't run them. My '79 Rough Rider was second hand without a box. This may explain why my Buggy Champ bought in 2009 sits unopened, my scorcher hasn't run and I've got Buggy Champ and Scorcher body sets to finish. Probably need some therapy to unwrap that one! Anyway back to '79. KP

Thanks, next time I change the pinion I'll pay attention to the fit. Next up was the suspension. The next few photos show the front suspension with the fibre damper mount and cardan drive shafts included in the kit. I was intrigued by the cardan joint and had not heard this term before. I've only got experience of low end RC cars and was aware of what are commonly referred to as CVs tend not to be constant velocity. A bit of googling and it would appear what we have here is a double cardan joint and is a true constant velocity joint. https://en.wikipedia.org/wiki/Constant-velocity_joint#Double_Cardan I expect the subtle improvement in performance this offers will be wasted on me! Rear suspension. These photos show the different drive shaft arrangement for the rear with the type of driveshaft I'm more familiar with. I've not worked out why the double cardan drive shaft is only fitted at the front. Anybody understand the reason why? Do the TRFs come with double cardans at both ends? The middle picture shows a close up of the rear suspension mount with the square plastic bushings. A number of different plastic bushings are provided. These change the location of the end of the suspension shaft allowing toe and skid angles to be changed. I stuck with the default which is 2.5deg toe in and 0deg skid. While building up the suspension I used shims for the first time during a build. This noticeably reduced the slop. KP

Next up was fitting the motor. I don't want to break any records but wanted something as a start point that was reasonably priced and could be used in other future builds. I’ve got a DT-03 with a Robitronic Razer Ten combo with a 3000kv motor that I’m happy with (See note below) and decided to go with the Razer Ten 4600kv combo. For the rest of the power system I’ll start with the current pair of old batteries I’ve got; a 3500mAh NiMh & a 4200mAh 25C Lipo. This will certainly be fast enough for me to learn the car and how to drive in a straight line! For this stage, as well as the Robitronic Razer Ten Combo with 4600kv motor & 60A ESC I fitted the following:- Robinson Racing 22T, (25T & 28T) Pinions Yeah Racing Aluminium Motor Mount I fitted the 22T pinion. So to start I'll be running 22T pinion, 68T spur. Here's the point I realised I'm doing pretty rubbish for a build thread. The first post was pretty lacking in pictures. I get carried away enjoying the building and just forget to take pictures! One area of doubt I've had was getting the gear mesh right. With the adjustable motor mount the procedure was a bit of a faf. Fit motor to mount, don't tighten bolts, fit mount to chassis, set mesh, tighten top motor screw, remove motor mount, tighten bottom motor screw, refit mount to chassis. After doing this the next step is to fit the top cover for the gears. After fitting the top cover for the gears the mesh felt to have "tightened" up. I was judging this by feeling the backlash by turning the prop shaft joint. My guess was the adjustable motor mount was not seating perfectly in the chassis and/or the gear cover. Took it apart, checked, couldn't see a problem, reassembled, still a bit tight. Took it all apart again and set the mesh slightly loose, reassembled and the mesh felt OK. Now I'm far from an expert and am not 100% confident. Any top tips or similar experiences setting up the mesh using the Yeah Racing mount? KP (Note below - My DT-03 came as a combo from Tamico. At 106 Euros this was an absolute bargain that included the kit, bearings, CVAs and a Razer Ten motor/ESC combo.)

The first few stages was installing the centre drive shaft and spur gear followed by building up the diffs. The following hop ups were installed at this stage:- 54500 - High Speed Gear Set 54501 - Aluminium Prop Shaft 5402 - Aluminium Prop Shaft Joints The high speed gear set comes with a 68T spur. This will give a slight increase in top speed compared with the stock 70T spur. More importantly it enables a whole range of different standard spur gears to be fitted. This enables a wide range of different pinion/spur combinations to be fitted. I got a 64T spur (51356) that I will be fitting later once up happy with the set up of the car. The kit included a spool to lock the front diff and a fluid filled rear diff. The googling I'd done suggested for speed runs a locked front diff was the way to go. There was some difference of opinion for rear diffs - some said locked some just very stiff. I went with 1 million cst fluid. This only just meets the definition of fluid! and it took ages to "pour" into the diff. KP

This thread is going to be a brief summary for the build of a TT02-SR chassis as a speed run car followed by the trials and tribulations of running the car. I’ve been inspired by the multiyear, multipart “Tamiyaclub Official Top 10 Fastest RC'ers” thread. I’ve even got an entry for a completely stock TL-01 near the bottom of one of the tables with an eye watering 16 MPH. This all started with wanting a “different” on road car to run. I already had a Porsche RSR and loving all things VW and Porsche the Porsche 911 GT1 Street TA03R-S seemed to fit the bill as I’ve never had a belt drive car. But as a chassis, the battery compartment seemed a bit limiting. I wasn’t sure it could fit lipos, it definitely wouldn’t fit a tall 3S lipo and I didn’t like how exposed the battery would be. For me, another negative was being short wheelbase other standard wheelbase bodies wouldn’t fit nicely. As the eventual aim was always to get a speed run focused body I decided to explore the different chassis kits available. Although I could probably stretch to one of the higher priced chassis, for that sort of outlay I know I’d be ****htened to crash it. I wasn’t previously aware of all the different TT-02 chassis kits and after a bit of deliberation ended up with the TT-02 SR. This seemed to offer a good balance of essential hops (bearings & CVAs), adjustability and other hops ups right off the bat. There’s a load of good TT-02 stuff at the rcracer.com https://www.thercracer.com/2014/08/tamiya-tt02-guide-mods-tuning-and-tips.html and this was excellent to get an idea of the different TT-02 chassis kits and hop ups. Link to the Tamiya product description https://www.tamiya.com/english/products/47439/index.htm I got the kit from Tamico https://tamico.de/Tamiya-47439-TT-02-Type-SR-Chassis-Bausatz KP

Final (for now) bits arrived for the next build. KP

Ok, so the big box of stuff arrived today for my speed run build. Also in the box were a new party frock and shoes for my Avante Black. KP