3D Printed Snowcat on Sand - Will it Survive?

thanks to morningbrew for sponsoring this video more on them later it's time for another update on the injection molded snow cat tracks project if you're confused as to what that is about 10 months ago i did a kickstarter campaign to raise four thousand dollars for an injection mold and ended up raising quite a bit more so now i've developed a full tracked vehicle kit that kickstarter backers will be able to purchase at cost it will include everything they'll need except the battery rc radio and 3d printed parts they'll need to print themselves if you want more info on this project go back and watch the previous three videos about it and check the kickstarter updates to follow along with the manufacturing procurement during the last video some viewers were asking if this thing would work in the sand so i brought it out here to the sand dunes to test it out sick looks great now i certainly didn't design it for the sand but i figured this would be a good torture test to uncover any weak points in the design these are 3d printed shell halves and i just sealed them up with tape to try and keep sand out at first it seemed to work really well [Music] so [Music] uh-oh we got a stripped gear surprisingly the finer pitched 93 tooth gears did not break but the big 3d printed ones did the sand was getting through the 3d printed chassis halves the 3d printed material is porous enough as to where the sand particles were actually fitting through the lines and getting into it that problem ends here i got these new vacuum formed polycarbonate chassis halves to test out these are the first prototypes with some of the extra kickstarter money i bought a mold for these vacuum forming works by heating up a piece of plastic and then putting the mold up into it and drawing the plastic down over the mold with a vacuum then the mold is removed and the part is taken off the machine and then later the edge is trimmed off and a bunch of holes are drilled in it with a four axis cnc machine so after the sand test i took everything apart and cleaned all the sand out after my last video someone with access to a mark forged metal x 3d printer reached out and offered to print any parts that i wanted i thought well sure it'd be cool to have some of the gears made in steel because then i could just crush up the sand now this obviously isn't plan of record for the kit version but i thought it would be super fun to try out they're made of solid tool steel these things are so dense and heavy like they're it's legitimate steel this is my first time seeing metal 3d printed parts and i was super impressed the metal filament is fdm printed and then it's centered later so they still have all the little lines and ridges like normal fdm printers create i was trying to tap holes in the steel for bolts and it is super tough i broke a tap in the process all the gears for one vehicle weigh 1.2 pounds pretty crazy so after that i removed all the sandy plastic gears and replaced them with the metal gears and i also installed the vacuum formed polycarbonate chassis prototypes the metal gears work great but man they sure are noisy noisy enough to really piss off this dog big thanks to morningbrew for sponsoring this video if you're anything like me you probably open up your phone first thing in the morning and immediately get distracted by random internet videos of who knows what definitely entertaining but probably not the smartest use of your time i like to stay up to date with what's going on in the world but for a busy person like me checking all the different news sources takes too much time instead i signed up for morningbrew it's a free daily newsletter that gets you up to speed on business news in less than five minutes it's witty relevant and informative and helps you stay in the know so you can seem like a smarter and more interesting person when you're talking to your friends or co-workers in just this morning's email alone i learned that ribbian is somehow now the third most valuable automaker in the world despite the fact that they've only shipped 156 vehicles consumer confidence fell to its lowest level in decades despite the fact that retail sales are up and puff bars is the new jewel but that doesn't really matter now because the vaping epidemic amongst high school kids is quickly slowing down see all great info that you should know and all you have to do is sign up for morning brew it takes less than 15 seconds and is completely free to subscribe click on the link in the description below to subscribe to morning brew today now back to the video so at this point i was using brass pinion gears and since these metal gears have little fdm printer ridges in them they were really wearing out the brass gears quickly so because of this i switched the 3d printed 93 tooth gears over to some machined steel 93 tooth gears and these were plan of record for the kit for a while but i switched away from that partially because they were going to be like 10 each gear so that would have been like 20 dollars per snow cat kit so not doing that anymore but it helped slow down the erosion of the brass pinion gear i've also switched to steel pinion gears since then it was around this time that pantheon reached out they're a startup out of vancouver that makes super high speed industrial grade 3d printers they use servo motors and lead screws so that they're super precise and super fast and they printed out a whole new set of prototype parts for them so big thanks to them you can see just how crazy fast their machine is they printed up all the parts in a fraction of the time it would have taken me so that's awesome after that i rebuilt the snow cap with all these new parts here's a shot of installing the heat stake inserts the kit will use quite a bit of these to hold everything together and you'll need a soldering iron to install them here's putting on the new steel pinions assembling the gearbox i still have the metal 3d printed gears in there putting everything together there's the two gearboxes going together and then putting it all on the chassis with the polycarbonate chassis halves and the treads and then i took this thing on a trip to california with me it works great in the ice plant kind of bounces along the top of the plants almost like it's hydroplaning definitely not its intended use but it seems like the perfect vehicle for this type of terrain it just floats on top although it does get covered in goop afterwards if you followed the kickstarter updates you know there was a problem with tolerance stack up on the tracks that would cause a twist i went back and forth with the injection molding company for a while and eventually they were able to tweak their parameters and get it sorted out these new tracks have almost no twist which is great i was really concerned about this for a while then i decided to try it out in the sand again so today i brought the tank down to the beach hopefully it doesn't just get destroyed again i think it'll be all right because this time we have the polycarbonate shell i have all the edges taped off right now so sand shouldn't get through there the only places that sand might get through are the axle holes the edge is taped across but the axle holes are still sort of open but even if it does the gears are 3d printed steel so it should just crush the sand after about 10 minutes of driving in the sand i looked inside and there was definitely sand that got in ugh look at that pretty gnarly so then i got the sand out put it all back together and resealed the thing with more tape but this time i put the tape right up against the axles so that it was a really tight fit and sand would have a harder time getting in now the plan of record is to use this extruded rubber h seal to go around the chassis halves and hold them together and i bought a mold for this and everything it wasn't that expensive it ended up not working as well as i would have hoped it's kind of difficult to install all around the chassis and it still doesn't seal the chassis halves around the axles so so not the best solution i think for the kit we're going to end up just using tape to seal it it kind of takes a sec but it actually takes less time than installing all this h-seal tube stuff so oh well tape works just fine and you get the best seal that way ideally you won't end up having to take the thing apart that frequently anyways so then it was back to the beach to do more sand testing shredding the gnar hitting some little jumps and i drove around there for like probably 15 minutes and then looked inside and there was no sand hooray after that i was back home and decided it was time to do a lifetime test to see how long this prototype would last of driving continuously so i built this little spinner thing this is a slip ring it basically just allows electricity to pass through while it's spinning and i 3d printed some parts and installed them all around the slip ring with some bearings to bear the load and here's the little spinner arm going on there on the top it just spins around and around doesn't matter how many times and then printed some bits to go on top of the tank to hold a string you might be able to see where i'm going with this hammered a stake into the ground and put the spinner on top with a string i had to make sure that i get the maximum diameter out of my small yard okay i've got the string all hooked up let's try this out this way it would just drive in circles all day long without me having to do any intervention now pay attention to how my yard looks here because it changes a lot after this thing's been driving around for a while [Applause] after quite a few hours of driving the metal gears showed a tiny bit of sign of wear which is kind of surprising i would think they would have shown almost no signs of wear but towards the insides you can see how the little 3d printed fdm ridges were kind of smoothed out just from contact with the other gear that could have been primarily from sand getting stuck in there and kind of sand blasting everything down smooth but so after that just out of curiosity i installed a new flat tooth 3d printed gear set in there and put it back on the lifetime tester spinner to see how it would hold up i have my ef delta power bank here powering the snow cat off its 12 volt output and that's enough to run it for several days because it only pulls like 25 or 30 watts as it's going around in a circle and then to prevent the inactivity alarm on my rc radio from going off i put a popsicle stick on and had the string wiggle it that was not a permanent solution and i ended up switching over to a servo tester to just set it and have it drive all day no planned obsolescence here people we're gonna make this kit so that it lasts for a really long time you can see how over time the vegetation starts to wear in and a clear track emerges where this thing has been driving after a few days of driving with these 3d printed gears to my surprise the first thing to fail was not the gear teeth themselves but actually the center of the gear [Music] that's probably because this design was meant to be cnc machined in steel and not 3d printed this kind of reminds me of the rover project where the point was to see how long all these 3d printed parts would last so then i replaced both of these with the new potential injection moldable candidate still 3d printed out of pla but with the same design that i would end up injection molding assembled that back into the gearbox flat teeth this time no herringbones you can't injection mold herringbone gears because you know the mold wouldn't be able to pull out and then put that back on the lifetime spinner and ran it for quite some time after a few days of this the wheels were showing significant signs of wear this is probably just from turning in one direction the whole time here you can see on the track links there's little grooves from little bits of sand and dirt getting stuck in there but the tracks were holding up really well the bronze bushings and shoulder bolts were holding up especially well considering that i hadn't even lubricated them but some of the nylon was getting worn out pretty quickly from the constant turning here you can see the edge gets kind of sharp where the wheel has been wearing it down where on the other side it's still like a thicker wall but most people probably won't be turning in the same direction for days so i don't think this will be a problem with the kit after a few days of driving the 3d printed pla gears were actually holding up really well now keep in mind this is just driving at a consistent speed i think accelerating quickly would be what really does these 3d printed gears in but i was surprised at how well they had done after several days so after that i bought a mold for this glass-filled nylon gear thanks to all those kickstarter dollars in the past i tried machining nylon and that didn't work out too well but injection molded nylon is stronger and i think those old machined nylon prototypes were made of some pretty crappy nylon so i installed these new gears in the gearbox and had to change a few dimensions so i had to print all new parts luckily the 3d printer company flashforge sent me their new adventure 4 3d printer it's fully enclosed and that's nice because it keeps the air inside at a consistent temperature and that's a lot better for printing with exotic filaments and it also keeps the smells inside and it has an air filter so that you can print with stuff like abs and it doesn't stink up your room it comes with its own slicer software that's pretty nice and it connects via wi-fi so you can just send the print from your computer right to the printer all over wi-fi and you don't even have to plug in an sd card or anything like that it has a built-in print cam which is pretty cool for monitoring your prints from somewhere else and i really like this printer it's pretty nice has a pretty small build volume so it's not the best for printing large things but for most parts it's great so then i assembled this new design to test out the injection molded gears and this time to seal up the two chassis halves i used this 3m rubbery tape it's kind of like electrical tape but not quite as soft to seal up the two chassis halves and that worked pretty well put the gearbox all back together and i was using a petroleum jelly as lube which seems to work pretty well then i installed the rest of the frame put it back in the polycarbonate chassis and after that i let it run for seven whole days only during the day though not during the night because it's kind of noisy and i didn't want to piss off my neighbors rain or shine this thing would just drive in a circle all day long luckily these nylon gears are a lot quieter than the 3d printed metal gears so it didn't piss off the neighbors too much a few times the pole in the middle got pulled out of the ground because it was just being yanked in a circle constantly so i had to reset that the ground here is super soggy it definitely started wearing a pretty significant track in the ground and even started to chew through wood roots a little bit this is a great lifetime test for the tracks i think i'm going to make a video about this vehicle tether thing in the future if i can manage to keep it going for the next few months rain or shine it would just keep going driving in a circle or rain and shine at the same time even through fire wow not recommended [Music] after that whole week of driving the nylon gears looked totally fine but like i said before this is like not super fast accelerations it's just constant smooth driving so i figured that i needed to do some thrashing to really put them through the ringer [Music] so then i took it out and just drove really hard like a maniac to try and break things but it didn't break so i'm really happy about these injection molded gears they seem great and they're super cheap since we have an injection mold so each kit will contain two sets of them so if you do break one which i don't think you will at least not for a while you'll have a spare hooray so now here's some epic high-speed footage from the freefly systems wave camera to keep your eyeballs entertained while i talk about the manufacturing timeline and stuff like that so all the parts where the entire snow cat kit have been ordered so kits will start shipping once the manufacturing for everything finishes and it's all shipped to my house and then it'll take me some more time to assemble all the kits if everything goes off without a hitch this should take around six weeks or so from the time this video is uploaded but who knows what'll actually happen so i'm not making any promises and i'm also not going to start taking orders until all the components have arrived because then i'll know exactly how much it all costs including shipping and i can set the price appropriately some of the parts have already started to arrive kickstarter backers will be able to purchase it all at cost and everyone else will be able to purchase it at a little more than cost because i have to feed myself somehow this is capitalism baby for more frequent updates check out the kickstarter update page if you're interested in designing a body for the vehicle check out the kickstarter update from august 11th there i posted a link to the dimensions and cad so you can design something from that i have not designed any bodies myself yet but i definitely want to design one that holds a lot of batteries and fpv gear because i want to use this thing for some long range fpv missions in the mountains so that'll be fun anyways that's all for this video here's a song about the snow cap by max radke thanks for watching bye when you're sitting inside on a snowy day [Music] wondering [Music] one idea that you won't regret is a visiting rc test flight on [Music] download all those big old stl files i'm sure [Music] i'm talking about the rc test take it up to the woods [Music] all from the convenience of your remote control if you build this amazing snowcat you'll be flying down the hill faster than a bobcat don't spend your money on drugs buy a snow can instead [Music]

Channel: rctestflight

Views: 392,089

Keywords: rctestflight, 3D printed, snowcat, tank, tracked, tracks, kit, kickstarter

Id: aeWgBARCtTw

Length: 18min 14sec (1094 seconds)

Published: Sun Nov 21 2021