Tarmo4 Build Guide with Skull Cover and Wing 

Good tip! I found that out the hard way as well.

Thanks man, I'll tone the volume on that down for future videos. :)

yeah the T5 requires a bigger diameter wheel for sure. BOM suggests these: www.amazon.com/gp/product/B014GQMFWY I'm actually using these which are similar to the recommended ones but slightly larger: www.amazon.ca/gp/product/B09KHM5SHK The diameter of the inside of the wheel on mine is about 75mm and they're already pretty close to the steering arms so I wouldn't want to go very much smaller on the inside. BOM says not to get tires that are any bigger than 120mm OD so I'd stick with that recommendation too. I think you could looks for tires for a traxxas slash or similar short course truck they will probably work.

Thanks dude! Have fun with your build!

No prob man, thanks for the awesome project!

@@rcprinter you do know this isn't engineering nonsense? I think this guy is just a fan

@@lio1234234 No, it's me haha. This is my other account.

Hi there, if you're running a 3s LIPO I'd recommend pulling back to 2s until you sort some of the issues out. Are you using TPU for your driveshafts? Those help a lot. Are you running tires with less than 100mm OD? Mostly I was breaking bell housings a lot although my dogbones were always fine. Try posting to the reddit group engineeringns for some help

​@@rcprinter well, I don't even have 2s battery - only 3 different 3s from other projects. Driveshaft is printed with TPU and no issues at all after I put some epoxy into the housing before putting the gears into it. Another issue was the battery plate height - it was too low so it melted at the bottom damaging the driveshaft so I reprinted the holder with bigger height. The rear dogbones and bell housings ripped off couple of times when I was using the original design. Now Im using a remix with hex locked diff and it works well for the time being. I have the feeling that it breaks off when rocks from the front hit the rear dogbones. Now I usually drive on the concrete and its okay. As for the front - last sunday I lost front drivetrain (small gear melted). Also the dogbones melted into the bell housings. Reprinted everything with PLA+ which seems much stronger and waiting for a better weather to test it out. If that wont work I will switch to metal dogbones + housings + gears. Tires have 96mm The car itself gives a lot of fun so it would be very nice to make it more reliable

Built robak2 as a replacement for Tarmo. While it has all metal drivetrain it’s far more reliable

@ sweet, I just finished my first robak2 a few days ago. I thought some parts I had lying around would fit well but they weren't perfect so I'm waiting for a few upgrade parts to be delivered before pushing it hard. Looking forward to seeing how much abuse it can take! Seems to need really large wheels for the size of it which is odd...

@@rcprinter I 3d printed the tires as well. There is a discord channel with all the robak info. Also, couple of days ago version 2.1 was released. If you want to use it with 3s battery you should reprint the diffs case.

Checked out your channel... looks awesome and massive!

Try here for a list of Tarmo4 accessories github.com/buldo/awesome-tarmo4 ... I think this is the one I used: www.thingiverse.com/thing:4552794

TPU driveshafts are important for torque damping in this build. TPU is pretty easy to print, I'd give it a shot. I don't think there's easy off the shelf replacements on amazon unfortunately.

Yeah I've tried PETG quite a bit. In my experience it's no better than PLA and in many cases worse. What works for me is to print with many walls and high infill. On pieces that break a lot and have high stress (drivetrain, suspension, steering) I print with 100% infill and it helps for sure. Nylon would help I'm pretty sure but I haven't had much success printing it yet.

@@rcprinter Well that is terrible news.. just spent two days printing everything in PETG thinking I was smart :P From my experience with drones.. PETG handles crashes better because it does flex a little. But I did not do any real testing... every crash is different.

@@bassohollic I have a few cars done in petg but I just print in PLA now. The difference is pretty minimal either way so you'll be fine.

@@rcprinter Maybe you haven't tried StrongHero3D PETG+ printed at 250º? I made several drone parts for a DJI S900 and the stuff is really hard to break or bend. When printing PETG I always go for 0.15 layer height @250º C wall thickness of 8 and 3 to 4 layers top and bottom. PS: Fan should be turned off as well.

Thank you!

I've definitely had issues but mostly they've been due to my own incompetence from not following the print guidelines at the start. After reprinting a few things the way they were supposed to be done the first time it's becoming a lot more reliable. I originally printed the gears in petg and I had major issues with them to start. PLA has been far more reliable for me for gears but I haven't tried abs. Been having some issues with the rear bell housings snapping off lately so I'm gonna try one of the mods on thingiverse for that. I'm pretty happy with how much fun it is to drive but I don't think it'll stand up to too much bashing abuse. Drifting would be fun with it for sure, I'll check out your vid on that!

Try www.thingiverse.com/thing:4690079/files this has part pla part tpu and lasts longer (at least for me) (does need bolts tho)

I am building this whole thing out of PETG

I guess theoretically if you removed the front driveshaft then you wouldn't need the front gears but I'm not sure how it would perform as 2wd. If you want a 2wd I'd recommend just building the upgraded tarmo5.

yeah you need to get the traxxas gears separately for this model.

Hey there, 12a is the dogbone and its here with the drivetrain files: www.thingiverse.com/thing:4178625/files 1of3 Chassis: www.thingiverse.com/thing:4178426/files 2of3 Suspension: www.thingiverse.com/thing:4178427/files 3of3 Drivetrain: www.thingiverse.com/thing:4178625/files

Yup, TPU for the driveshafts and the front lower arm bracket and then PLA for everything else. The recommended TPU is ninjatek cheetah but I just used a cheaper one off amazon and it worked fine although I have seen a few reddit posts of people complaining their driveshafts have torn I haven't had any issues with mine.

hmmm, I printed the skull on an ender3 standing upright with a 250mm build height but the Mk3s is a little shorter so I can see why you might be having issues. You could try splitting it in half and then gluing it together which I assume is what you need to do if you're printing the extended skull anyawys which is even bigger: www.youmagine.com/designs/tarmo4-skull-extended

@@rcprinter exactly prusa is smaller on Z

I used these: www.amazon.com/gp/product/B07FS2SFQN

Plus it's just fun to do!

Did you print them in TPU? No issues with mine so far.

@@rcprinter They are Hatchbox TPU and they rip apart inbetween layers every like 30 seconds. (But Im only in rwd so thats probably part of the problem) (I have my esc set to punch level 2/9)

and im only at 25% speed and 50% brake force

@@xaviertwilight7855 hmmm, that's gotta be frustrating I'm sure... I'd suggest maybe trying a higher temp for better layer adhesion and if that still doesn't work maybe try overextruding (increase flow) a % or 2 or try a different tpu.

@@rcprinter thanks👍