3d printed RC cars. A double review of 3Dsets and tarmo5

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I’ve mentioned here and there that I’ve been printing RC cars. There’s been some curiosity, so I thought I should try so sum up my experiences so far.

Tarmo5:
A sturdy design! Developed by a guy called “engineering nonsense”/engineeringNS. 5th iteration. 2WD. The car is a fast street/drift car. I think I reached about 60km/t. Such speeds demands an ESC with gyro. The tarmo5 is a great way to get into RC cars in general. Simple construction and great execution. BUUUT - the model has quite a few flaws. The tolerances are not good, a lot of slack in the joints. The developer seems absent from the feedback at reddit, but there’s a lot of modifications circulating. If someone was to try this, I would go for one of the tarmo5 remixes that seemed reliable and well thought through. I modified the main gears from spur to herringbone. (quite proud of that actually. Making gears seemed out of reach, but it wasn’t so difficult!) The herringbone gear decreased noise and wear and helped the gear stay more in line.

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(videos of the cars can be found on my instagram feed, askevold_net (buried between a lots of mishaps))

3dsets Bamboo 4x4:
Hundres of hundreds of printed parts and fasteners. Printing takes a long time, and assembling takes a long time. But boy these models are well made! The gear box is super satisfying, the parts have amazing tolerances and fits really well. (most of them, had some issues with the open diff). The 3Dsets car is nice to look at and can be kept on a shelf as decoration. And it’s impressive what they are able to accomplish with PLA and a few parts of PC. BUT - the obvious drawback is that this car is not capable at all compared to a regular crawler. Tipping over on a flat round can break stuff, even at low speeds. But hey, you can print new parts yes? It’s a good idea, but annoying in the long run.

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SO - if I was to do it all over again? I think I’d do the same run. Making both of them has been a great learning experience, it has taught me a lot about 4WD vs 2WD, open and closed diffs, brushed and brushless motors. If I was to suggest ONE printed car, I’d might go for the Buggy/Sakura/sports at 3dets. Nice looking drifters with belted gears and brushless engine. Great for a quick fun drive on flat ground.

If you ask what cars are kid friendly? The Bamboo (crawler) is supposed to go slower than the street cars, but if the kids is stubborn enough, they always find a way to break stuff. Turning down the throttle on a street car might be just as well. Crawling is a fun activity, but kinda frustrating when tipping risks braking stuff.

A few direct comparisons:
The tarmo5 motor is BEEEFY compared to the 3dsets. I’m not sure if the tarmo actually needs such a big motor?
Price! Tarmo5 is free and open source, while 3Dsets is a professional firm that takes a decent price. (50USD). I think it’s worth in in terms of mechanical and aesthetic quality.

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Thanks for the nice update. I’ve had the Sleipnir on my list for ages but haven’t gotten around to building it yet. It’s a modified (supposedly) better version of the Tarmo.

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The Sleipnir seems like an interesting variant. Using metal parts for the drive train and steering rods seems like a good idea. But I still wonder if the build is balanced and mechanically well made. Not easy to determine… kind of off putting that the car flips over when turning at high speeds? Perhaps that’s common, I don’t know :smiley:

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On pavement, the RC cars I’ve driven just drift.

On dirt or grass they can roll. But only if they are going quite fast and then they roll a couple of dozen times.

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Ive heard from various sports car clubs “You can’t roll a _____”. Answer: “You’re not trying hard enough.”

Drift along into just the right size bump and you can roll your RC drifter. Get going a bit and you can launch it. Somewhat upsetting after spending days on a paint job and your car goes spinning across the pavement on its hood and roof, but it most certainly can be done. It’s even easier with something that’s supposed to be able to go off road, because of the higher cg.

Been looking at printed RC cars myself. The Tarmo looks promising, the OpenRC F1 also looks good, and some of the scale cars look absolutely amazing. I think I’m looking for something with a metal drive system and a modular body that I could swap to look like different cars. I considered the idea of modelling a commercially available chassis and doing body kits from available car models, too. Some is a matter of trust in my 3D printers, some in the figuring out CAD to put stuff together, but most if it is finding the time between work, and too many hobbies.

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