Nikko85

The RadioShack have a model that works well, it's an almost perfect 1/14 scaled down LB. I will find the model.

Thanks, it handles like a smaller, lighter, nimbler CW01, without the bump steer.

A quick 10 min blast I've now idea how @Re-Bugged gets such amazing airborne shots, whilst I struggle to take a photo of a simple wheelie!

Yes, I had not noticed they were the same! I played around with the gearbox, just trying to get it as quiet as my second QD. It's not quite there, so I'll play tomorrow. I'm not sure if it's a grease, mesh, motor or pinion thing, but it seems to squeal more. I also replaced all the screws with 3 mm stainless screws. For most of the screws you can use 12 mm ones, apart from the battery holder side panels which need 8 mm. I also tried out some wheelies. To be honest the wheelie bar is too pushed out, meaning the car doesn't angle back enough, and so the wheelies are quiet short. The original printed design was for the FJ45, where it needed a much longer wheelie bar to protect the bed of the car. I may design a shorter wheelie bar which allows the truck to get much more vertical, which should increase stability.

I found out recently that the Agrios was based on the Bigfoot 18, so that could be an option to paint?

A quick update on this, but first a recap as it's changed around a bit This started as the Thunder Tiger PUBG 4x4 which is the same as the Team Associated CR12. I added a Proline Chevy body and GF01 115 mm wheels + tires to make a monster truck. I added a 390 motor, but that slowed it down. I then decided to shorten it to fit a Pumpkin body by trimming the links and drive shaft. I added steel bevel gears in the axles, metal gears in the gearbox and a brushless motor, but the brushless motor destroyed the steel gears, due to a bad gearbox design. That was the last time it really ran. I decided to almost call it quits, when @OldSchoolRC1 suggested the new Enduro 12 is very similar and the gearbox might work. And it does! The new gearbox seems a more standard arrangement. It's pretty much drop in, although I did need to drill out a couple of threaded holes, but super straight forward to install. All the original parts and bearings fit perfectly. The new gearbox sounds much nicer and overall it seems an upgrade. It's a much better set up. The huge distance between motor and pinion is much reduced, meaning I can use other motors if needed. You can adjust the mesh just by taking offer the cover, which is a huge advantage, and overall it seems sturdier. The CR12 got a lot of criticism for shredded gears, so I hope this helps. I will have to fabricate a new battery plate, as the old one no longer fits with the new motor, but that should be easy to do. So, what's the new plan? Running with a hardbody just throws the weight off this too much, it's such a light truck that the weight up top makes suspension, motor heat and handling suffer, so I will stick with a lexan body. This also means I can keep the brushed 370 motor, at least for the time being. With this in mind I want to make a 1/16 scale Bigfoot #18, to match the QD Bigfoot #1 I've just completed. I like the idea of a vintage and modern monster truck running together. This is starting point Compared to the Quick Drive: They are actually not bad to scale. The Bigfoot #18 was pretty massive, and in reality my QD bigfoot is using a slightly smaller Ford than the original! If it also looks familiar it's because the Agrios was also based on the Bigfoot #18. So the plan now is to paint, sticker and vinyl. I think I am going to go for this kind of livery Printing my own stickers. It won't be a full match of course - it's a rough approximation of the body shell (it's a generic Traxxas) but I hope it looks good enough when all done.

Those look great. I am quite jealous of the Clod. Lovely looking car. I will run this, I just need to find the time!

Well, this problem wasn't a screwdriver problem, but a 3D printer problem. However I think I spent around an hour last night not really doing anything, but just holding various servos to try and see how the steering might be fixed. The stock steering is odd. In order to have enough space for the front motor and gearbox they have put some of the steering mechanism outside. The steering rack moves back and forth as the steering horn rotates, but both rack and horn are on the outsides of the car. I spent a lot of time working out how to make this work, when I realised I could mount a small servo upside down which connects directly to the horn. The current horn won't attach to a servo, so I 3D printed a new horn with a 15T spline for the small scale servo I am using. This does mean there is no servo saver, but I am hopeful that the small scale, low speed and metal gears will mean that won't be an issue. It's likely the spline may fail before the servo does, so I might have to think of the horns as semi-disposable. here are the horns, you can see how the horn is made of super basic shapes that then are blended together. I did use an STL of the 15T spline to add, as that was beyond me. I will test this evening.

Thinking with a screwdriver in hand is a great way of explaining it. Time can just disappear as you tinker, think and problem solve.

Many thanks - I try and get these cheaper but more interesting cars as as they are not "hobby grade" they are never fixed, so a part breaks in 1985, it's put back in the loft and is still pristine 38 years later (unlike me...) When I started this hobby there was lockdown, no toddler and work was less stressful, so I could actually drive quite a lot. These days I mainly fix and make as I've just a little time in the evening. I've got one car (CW01 Pumpkin) that is pretty much stock apart from a few upgrades, but I find that the problem solving and engineering is where I have the most fun with the hobby, so it's getting bodies to work on different cars or getting these toy grade cars to hobby grade electronic standards that I really enjoy. I'll never spend 3 hours masking, it's just not in my nature to be neat and meticulous, but I can spend 3 hours sorting out how to get a steering linkage to work.

In terms of total performance you are probably right, although I not sure of it's great to keep motors running with zero load. Also there might also be something to be said for engaging gears before motor turns on, given how thin the front gears are. When the servos turn up I will have a play. For other electronics I am hoping a HW1060 or carson 70 amp drag will provide enough power for the two motors parallel.

Many thanks @OldSchoolRC1 I took a punt and the new gearbox does in fact fit perfectly. I need to order a few new 2.5 mm screws but overall it went in without issue. It seems more sturdy and doesn't have the design flaws of the first generation The mesh is much easier to check and adjust. The very large distance between pinion and spur is reduced, meaning more motors will work. All in all great news. Looking forward to my next steps with this truck again, might even reopen brushless ideas. Thanks again for the idea, that would have totally passed me by.

Many thanks. I really like things like this which need a little thinking outside the box. I've realised rather than a switch to turn off the motor I could use a spring and battery connector from the original battery connections to make a simple contact switch, attached to the lever. I have ordered two small metal geared servos for the truck, one for the gear change and one for the steering, you don't need full size modern 1/10 servos for trucks of this size. These are due to arrive tomorrow, so I will have an explore of how they can connect up.

Another evening, another piece of RC Japanese Toy Grade history. Following the surprising success of my 1977 Nikko build I thought I'd try another vintage RC car, the Yonezewa Datsun from 1981. I know these aren't Tamiya, but they represent a golden age of RC, and hopefully someone might find it interesting. I picked up a broken pair on Ebay with the hope of getting at least one working model. I want modern electronics, so the fact there is no transmitter is not an issue. With the price I paid even if I just get a pair of cool bodies to go on something else (MF01x, GF01 etc.) then it wouldn't be a bad deal, but hopefully I can get something that actually goes. I say I hope I can get something working, as outside of one grainy video on Youtube I've not seen any photos of videos of the insides of this truck, so I've no idea how possible it will be. Some toy grade RCs are trivial to convert, others can be much trickier. One complication here is that the car has a 2WD / 4WD system. Although none of the literature says so, it's also got high and low gears as part of this. 4WD mode uses both sets of wheels on low gear with a locked differential at the front and open at the rear, for nice crawling action. When you hit high gear the gear selector mechanism moves the gear at the back to high, but also turns off the front motor and also pulls apart the spur and pinion at the front, which in turns opens the diff. So you have a low geared 4WD system, with a RWD high gear with open diffs, utter genius. To do this the high/low gear selector sits as part of an electrical switch, which tells the PCB to turn off the front motor. It's quite impressive that in 1981 you had features that would still be selling points today (until Traxxas patents them, of course...) You can see here how the gear shift lever runs pretty much the length of the car, running under the PCB. Here you can see the rear gearbox. A few things to note: The gears are really thin, so this is not going to want lots of power. The motors are also strange, they don't have positive and negative tabs - the entire motor is split in two, one half positive, the other negative. I've never seen that before. The good news is the motors both travel in the same direction which takes away timing issues. An open diff is present. Everything spins freely. The front gearbox is even more interesting. The spur gear moves back and forth along the pinion. In "on" position it engages with both white and black gears, locking the diff. As the spur gear is pushed back it stops engaging the gears, allowing wheels to spin independently - amazing! So, what's the plan? Well, I want to try and get this running using modern grade electronics if possible. For the gear selection, at the time this was done with a lever you'd push manually, but I'm hopefully I can get a servo on the 3rd channel doing this - so I can change on the fly. Moving a level which stretches to both gearboxes whilst also triggering a switch to turn off the front motor might be tricky. I will also have to route the front motor to the switch, which will mean lots of wiring. I will probably keep the original motors, although perhaps a 280 could fit with a small motor plate, but it looks doubtful, and might not be that more powerful. Plus I really don't want lots of power through this, it doesn't weigh much, so hopefully it won't need much. The steering servo looks pretty simple at least. If I can get it working I'll work on tires and body. The tires are quite dry, although not cracked, so I may try the WD40 trick, if anyone has actually tried that? As for the body, it's getting the red/white/blue classis nissan livery, as a vintage Rodger Mears style off roader! I may 3D print a new grill and lights to make it a little more classic looking. I will also remove the light and horn, and add some sort of roll bar and spare tire on the rear. Although this is going to be a runner, I'm really not looking at a performance vehicle (it's 43 years old, it has zero suspension etc.) but I hope I can bring a piece of RC history to life! Wish me luck.

Finally finished this, a quick drive Bigfoot 1.

So time to wrap this up, and then it would be great to see other users QD monster trucks. For this I decided to use a Taiyo (often released by Tandy and Radioshack) 4x4 done up in bigfoot style. I printed some brackets to hold the body posts, so I could use the holes in the body which are there for alternative shock mounting. The posts have sellotape around the base as they are 5 mm and I stupidly made them for 5.5 mm. I will reprint on Monday. And now the body can go on. Really happy with this! The roll bar is made from 5 mm aluminium tube hand bent. So what other QD trucks have people got? 😃

Many thanks, but I am looking for the ones that take the CW01 tire, as found in the mad bull, wr02 etc. Sorry, I should have been more specific.

Great work as always.

I've painted wheels before, and I've stripped off chrome wheels to make natural or black ones and then painted white. My issue is that I want to go from super strong yellow/orange to white, and should they get nicks in them, then the yellow shows through, and for some reason that bugs me more than if black or white were to be revealed under the paint (although if they were white wheels, painting yellow would be fine, go figure).

thanks, but mine are brushless, I use the Ezrun 2030 system, tiny little things, but enough speed for fun. If you've got pictures of the wheels I'd be keen to see them, Thanks,

Thanks, I'll have a look. I already have the tires in mind, so ideally would just pick up the wheels. It's for a QD purchase, so don't want to spend massive money. The Tamiya ones are available, but it's £22 a set, and I have to purchase tires at the same time, so it adds up to quite a lot, just to change wheel colour!

Are those to fit a classis CW01/GF01 tire? Sorry I should have specified! If so, yes, I would be interested! If you could send a picture (or model number) that would be awesome!

Nice. The monster trucks have a different hex, much closer to the MK1 buggies (thundershot and super sabre) which are just 7mm plain brass hex with splines on the inside. I did however pick some of these up for the QD buggy gearbox that arrived with this job lot! I have a rather special body planned for this, but in the meantime I thought I would test this, it's an FJ45 painted orange with matching orange wheels. Needs some livery but I might keep as an alternative runner shell. Looks pretty cool. The rear tires are the ones from the GF01TR, an interesting piece of Tamiya trivia, these were first released as a hop up for the QD range I am actually growing towards the orange. Might go for a monster truck livery perhaps! Good thing is that these bodies are cheap and plentiful so although I've never cracked one you feel a little more relaxed than driving with a 1988 QD clod body! Ps I can always send over a few 3d printed hex converters to anyone in the uk?

They also work with the QD buggies too. I saw it on @wolfdogstinkus QD Thunder Dragon thread, I would have never thought of it otherwise! It's a good piece of knowledge, as I've never seen the QD wheel hubs for sale anywhere.

With a brushless motor on the back these things will tend to wheelie, which means you need a wheelie bar. I designed a few on Tinker cad. They attach to the gearbox guard, with zero modifications needed of the chassis, So, now we are ready to put a body on! Obviously you've got the classis QD bodies you can use. The Beetle seems to be the most common one, followed by the Pumpkin, Blackfoot, then perhaps the Clod and Jeep, which are pretty rare and usually pretty expensive. As these cars were made in the late 80s lots of the bodies are toast, so there are many more chassis than good bodies, however there are a few options if you know where to look. The most easily available is the MN models FJ45 - this fits the wheelbase almost perfectly, arguably better than the GF01 FJ45! It's around £23 or so. The WPL D12 body also fits really nicely! However this one is going to have something a little different, which I will try and do tomorrow.