This was awesome. Maybe replace the belt drive with a gear drive. That way the force isn’t pulling on the axle. Also consider a 3D printed ball bearing design for the axles like the ones used for Filament Spools. It should spread out the surface contact.
Mount the drive gear and belt in the middle of the axle. This will distribute the pressure evenly. Using a bearing will only solve part of the problem. You need to distribute the force evenly. This is why in cars the transfer case is in the middle of the rear axle.
the problem with gear drive like stated in a previous video is that the motor's torque would destroy plastic to plastic gears. He could swap from the GT2 belt to a sprocket with a chain, but that would add more weight and also change the top speed of the RC car depending on the sprocket gear ratio..
@@toyotaboyhatman keep in mind, those are injection molded nylon. Also, keep in mind the weight of this model! If anyone has the exact mass, pls post it, but I think it was north of 20 kg BEFORE the motor and electronics were added!
That is completely wrong belt standard for that application, atleast go for 11mm or 15mm with. When it slips its always on the motor pulley since that has the fewest theeth that enganges. Its possible to run 2-4kW though a printed teeth pulley when done right :) Also with a slightly larger motor pulley you wouldn't need to overtighten the belt, and belt efficiency would be a lot higher. (For everyone that wants to learn about printed pulleys check out Tom Stanton's ebike on YT).
Mount the drive gear and belt in the middle of the axle. This will distribute the pressure evenly. You need to distribute the force evenly. This is why in cars the transfer case is in the middle of the rear axle. Widening the belt will only solve part of the problem. As Joel said the belt wasn't slipping it was the poorly distributed force on the rear axle bushings.
5 лет назад+1
@@Scott_C that wouldn't be that big of a problem if they used a method which transfers torque more evenly. Or just make the axle completely round at the bushing.
You want to find Super Lube, it's what we used on the RC cars back in the day, and of course bearings. www.amazon.com/Super-Lube-21030-Synthetic-Grease/dp/B07HR46FKV/ref=sr_1_4?ie=UTF8&qid=1545073686&sr=8-4&keywords=super+lube
use heavy ball brearing grease and stop fooling around. you cant expect any lubrication if the surfaces arent even smooth. No amount of grease will work if you have sandpaper against sandpaper
Heavy ball bearings can make a joke with this conctruction... IMO it's better to print some decent plastic bearings. With sizes where the rollers will not be micro-sized. And I could place two pairs of identical plastic bearings there. A lot of space. It will load off that axle good. Plus some good lube and it's done. Will not work on high speeds of course but these bearings will be lite-weighted and it's important IMO. But need to work with nylon or PETG (at least).
You need basicly every part proper made to drive it at any decent speed, plastic tires don't have grip, decent suspension and shocks, stronger axles, its fun that its possible to make, but to drive a decent car at that scale.. Think XO-1 or Shredder.
The bushings... oh... I facepalm here... actually I've didn't believed that these are not bearings... before he cracked up them. Badly printed bearings can be melted too... But not so easy and quickly. The 3dNerd did destroyed a good axle (a lot of plastic) to prove himself that bushings are not acceptable here :)
1)If you designed and 3d printed a gearbox for the motor you could then use a drive cog on the rear axel and reduce the loading created by the belt tensioning making the plastic parts last longer. 2) You could play round with printing bushing's with different materials, you could set up a jig in your workshop to see which one works best and last longest. 3) I know you are going to try keep as true to the original as possible but it doesn't surprise me you are finding you need to reinforce certain areas. The bigger motors tend to have more torque and also weight doesn't tend to scale particularly well so while it might be 4X scale i am guessing you are more than 4X the weight?
i just don't see the whole point of keeping everything plastic. Bearings are ceramic/metallic for a reason, and the belt system looks highly unprofessional. This project would've been more impressive, (not trying to undermine it) if some actual engineering calculations are done, instead of plain scaling up of a model.
the channel is 3D printing nerd... not professional RC Nerd... the point was to scale it up as much as possible, 3d print everything possible, and see if it would work. it did. now, he is making some changes so it works better. the project is 100% 3d printing centered, not to make something outside of 3d printing look professional. not too difficult to wrap your head around.
I dont understand what you mean by "engineering calculations" & "unprofessional" we still have tons of heavy machinery that are friction belt driven for their powertrain with shitty plastic tensioners. There is nothing wrong with their approach hell they even have a leg up using a toothed system.
There are plenty of motorcycles built today that use this belt style system, and some are even on the drag strip. I used to be scepticle about the idea until i saw the capabilities.
Why not print a pair of needle bearings? You could use 1.75mm filament sections for the needles and print the races. The graphite powder would only need to lubricate the surfaces between the needles.
Looking forward to "take 2" thank you for the many hours of enjoyment in 2018, I can't wait to see what you have ins store for us in 2019. Merry Christmas and a Happy New Year
This was awesome. Many things require many iterations to reach success. I love that you were willing to share the successes and failures and your plans to improve and make it better. Awesome work.
As a RC Car guy.... once you add the bearings you are going to have so much fun with this thing!!! This is an awesome and amazing project... I have really enjoyed your journey getting this bad boy to the point it is now and cannot wait to see how far you can take it... maybe you can race it one day with others that have built an 1/4 scale Open R/C. 🤔
Great project! I think what I like most is the mix of skills you need to finish this, designing, printing, gluing, electronics. I think it was a great idea to find experts for those sub steps and include them. If I could have wished for something, than it would have been a deeper look into the electronics.
Close, I spent 1 year in a 3d print airplane, it flew 3 seconds, and I am back to the next iteration, you cannot work in engineeging if you are not embracing failure as a learning process. Thanks! good luck with the bearings! wish me luck with my project
I completely agree, the belt is constantly pulling against the bearing causing excessive wear on the PLA bushing. If you look at the bushing it should look like an oval where the projective plane of the oval is parallel with the pulling force of the belt. The use of meshed gears would help to alleviate this as it would remove the tension of the belt. However there will be the constant tension of gravity exacerbated by heat on these PLA parts. The solution you propose should be "good enough", however if you want to run this at any speed for longer periods of time, but keep as much as this car PLA, then you need an inner and outer bearing surface where the parts meet and are under a friction load. Great show!
From an r/c guy, dump that belt setup. It's going to put too much stress on the axle as you found out. Print two carrier gears, rework the piece that mounts to the axle as a gear. Then print a cover to help keep everything aligned properly, and test again. Another reason to switch to gears is to control the possible speed the car can go.
Awesome!! - we all knew you were going to need to iterate the design especially for PLA on PLA and you were very clear about this. Can't wait to see the next run - hopefully at MRRF 2019.
I was nearly giddy when I saw the thumbnail then I felt do, so bad for you when it started having issues so soon. It moved! It's amazing in that aspect. I have been so enamored of this project. Why not go sith a wooden axle? I know you wanted to do as much of it out of PLA as possible but you used other materials when necessary. Why not step back and replace the axle with wood or metat. . . or even a different plastic like nylon that will resist the temperature? Cannot wait to see it really open up! Best wishes for the holidays to you and your family, Joel!
It's great to see it moving! I'd say the belt was slipping because the bearing was seizing. Friction welding can happen from high pressure or high speed. If this thing had long-term use in its future, it just needs bearings.
Joel love that it worked. Happier that you are going to try to fix the issues. You know that hole in the back is killing me though because I want to make it shoot fire!!!!
I understand wanting to make as much of this out of plastic/3D printing material as possible, but would it be possible to change up the wheels to either be more rugged or even just replace them with rubber tires so it has better grip? That way you should be able to go even faster without worrying too much about loss of traction and spinning out.
or even make plastic bearings, I have seen that they print the balls and the inner and outer raceways all assembled. I do agree with you, that a real bearing would be much better than a plastic one. Especially if they were to add weight to that car.
I love that you showed the problem area. Looking forward to the next revision! I hope to see it zoom pass the camera in the next video! I love that an iPhone was used to film that.
Some tips: 1) try bushings with different materials 2) try 3D printing bearings - this works (i can send you the stl if you give me the dimensions: D_out, Din, heigt) 3) the GT2 belt is rubbish - they are 0,75mm high - so if your belt is becomming ~2mm longer or the distance betwen the two axis becom ~1mm shorter they might skip as you experienced. therefore i woud use some biger belt ore chain -> bigger teeth means that you don't need that much tension therefore the bushings shoud work better
As you state in your postmortem. It was the pulling of the belt on one side of the axle which caused the high pressure on one side of the drive train. Mount the drive gear and belt in the middle of the axle. This will distribute the pressure evenly. Only using a bearing will only solve part of the problem. You need to distribute the force evenly. This is why in cars the transfer case is in the middle of the rear axle.
It’s alive! Congrats! What a wonderful maiden voyage on such a cool undertaking. Or is it an “upscaling”. IDK. I had a thought, is there any advantage to swapping the rings or the axel for 3D printed nylon or some higher heat tolerant filament? A bearing would be the most ideal though for sure. So fun to see it move in any case. Great job Joel.
Guessing this is the last video in the series so far? Loving it, just got my first 3d printer and it's not quite ready yet, but I'm super excited and loving your stuff. Are you just stuck on finding the right size bearings?
The huge size difference between the two pulley wheels means not many teeth are engaging on the motor's pulley. I think you need an idler wheel to push the loose belt down and get more teeth engaging with the pulley on the motor, and might have to relocate the motor a bit to accommodate that. And as an added bonus you can make the idler wheel adjustable and/or spring loaded so you can solve the belt tension problems.
So awesome seeing it move! If you are going to stick with belt drive, a spring loaded idler pulley to tension the belt might let you get away with less tension and adjustments. It can increase the belt contact area on the pulleys for more grip. You would end up with another pla on pla friction spot. Snowblower auger belts use this design. (can you guess what I fixed recently?😂)
After I watched this video I saw what you need sitting above my desk. Bearings from an old project. I'd be willing to donate them if you can make them work. They are 30mm on the inside, 42mm on the outside, and 7mm thick. They are brand new and I have loads of them. They are usually used for bicycle hubs, so they're pretty cheap common bearings. I totally get the desire to make as much as possible 3D printed, but we can't defy the laws of physics for long. If you need a different size I have a connection. It does take a few weeks to get things shipped, but I can get anything that's commonly made.
Every bursted bubble has a glory! Each abysmal failure makes a point! Every glowing path that goes astray, Shows you how to find a better way, So every time to stumble never grumble Next time you'll bumble even less! For up from the ashes, up from the ashes, grow the roses of success!!! ("The roses of success" in chitty chitty bang bang) this is my go to when something I worked on didn't go as planned. This isn't a failure only a momentary set back!
Good to see it finally moving, glad you're getting some real bearings on it. I have to wonder if 3d Printed roller bearings would do a nice job. Good luck.
Once you work out the Belts/Bushing/Axel. PLEASE try a couple layers of plasti-dip on the wheels like tread for grip. and MORE motor power. Awesome build!
Thoughts: 1. Mount another gear for the belt to the axle mount *behind* the axle. That way, all of the pressure from the belt will be balanced--up and back at the bottom of the axle gear & down and forward at the top of it. Yes, you won't have as many teeth engaging, but there won't be uneven pressure on the axle. Alternatively, use the current belt setup and add a second belt going to the rear (idle) gear. That would maximize the number of teeth engaged while also completely balancing the forward and backward forces on the axle. (Now that I think about it, to perfectly balance the forces acting on the axle, both the motor and idle gear should be mounted *below* the plane of the axle, as gravity will cause the mass of the vehicle to press the axle against the top of the bushing. By the belts pulling *down* on the axle, there would be less pressure against the top of the bushing.) 2. Use *two* bushings with a tiny gap between them that matches up with a reservoir built into the axle mount that holds a large quantity of graphite. That way there will be a constant source of lubrication. 3. Would a carbon fibre or metal-infused filament be considered cheating? If not, matching axle and bushing surfaces should reduce friction. 4. Mating surfaces should not just be sanded, but *lapped* until they are mirrors. That alone will reduce friction by an *incredible* amount. Hope this helps!
I’m willing to bet that the pla axle is going to be an issue even with a metal bearing. That thing has to be bowing under belt tension. Still an awesome project to undertake and I can’t wait to see where it goes from here. Kudos 3D Printing Nerd.
Brushless motors have a lot of torque so I suspect his gear ratio was way off for the motor. A much bigger pinion pulley and smaller spur pulley will give better tooth engagement on the belt so it won't need to be so tight. On racing RC F1 cars we are geared at about 1.8:1 with brushless motors. This one looked more like it was 50:1. Also if you use a coarse tooth instead of a fine tooth you'll get no slippage with only a slight amount of tension.
Next challenge should be : 1. Pin bearing /w automobile grease 2. Open Differential 3. Plastic Suspension (maybe leaf sus would be easy to build?) Lol I’d love to see that. Great work dude
Have you considered just skipping the problem altogether and going direct drive put the motor where the axle is and mount the wheel directly to the motor no friction issues :-)
@@linecraftman3907 I never had to jump off a cliff to learn i can fly. Some things are obvious, more if you know PLA isnt very heat resistant, it heats up quickly, and graphite only works on smooth surfaces (like inbetween the plates of a lock). Graphite is a thin powder, what makes you think it will stick and lubricate a piece which has grooves bigger than the graphite particles themselves?
@@BemerLuis I didnt kill the fun, they did by making the car very poorly so much it died mid testing. Also its exactly because im not illiterate that i can point out the obvious and blatant faults in their design.
Laharl Krichevskoy actually it’s because you’re observant that you noticed, you’re still illiterate, and this project is the point of trial and error. If they had the perfect design then it’d be a one and done video. And obviously you have no engineering prowess, you’re just a buzzkill
The greatest thing about this is that we're learning with you. Sure there are some that know a lot more but just being told the answer isn't as fun as working it out for yourself. And if you can't, THEN you can't listen to the experts.
Suggestion get rid of the belt drive, the belt needs tension to work, and creates high stress areas. Points of high friction in other areas. Gear drive can provide a lot less friction, you don't need to apply stress, your gears can float with proper adjustment. You can also control your speed by the gear ratio. Also what about plastic bearings? Yes I know the insanity of making them, but the benefits would be great. Just a thought.
Awesome work Joel! 👍🏻👊🏻 Perhaps besides the addition of the bearings and tensioner, using a toothed belt would help to reduce the amount of overall tension required to drive it without slippage.
I use 3d printed parts made froom Aprintapro PLA and PETG in my RC Scale Crawlers, they hold up to extremely rough handling on demanding trails. With the right lubrication and print settings you will be able to make it much more resiliant. I'd change the geometry of the drivewheel to use a coarse timing belt and use PETG on the bushings(this material tends to slip better on other PETG parts than PLA. you can drastically reduce the stress on the pully by adding more stages of transmission to increase torque. a gear ratio o 1:25 is considered aminimum in RC
Joel: What might also help with prolonging axle life would be if you made little crescent sections for where the axle rides in the bearing in order to make it a full circle there.
If you're going for 3d printed bushing possibly use acetal/POM/delrin. It has great low friction and wear resistance. I wonder how it would hold up with a pla axle rubbing against it.
What about using the gear bearing spinners for your bearings. I spun them up really fast with a drill and they stayed cool. I feel they would hold up for a while. I am talking about the same gear bearing Prusa has as a test print. Might have to scale it up due to your axle being so large.
Joel you need to go full bearing in all of the axles, I know you can make it move with just bearings on the rear, however I want to see this run as fast as it possibly can for as long as it can. You and many other have demonstrated that 3d printed parts can go a long way, however they have a limit on what they can accomplish by itself, doing a combination of 3d plastic and metal components is the best route. Another suggestion is to change the rear axle to something made of metal if possible like a threaded steel pipe :D. If I can do anything to help let me know.
I think people talking about plastic bushings welding to the axle were under the impression you weren't going to limit the power of the motor all the down to 15% . I personally have no clue what's going to happen
Hi great video Let me tell you some ideas i came up with while watching the video. -Use silicone grease for lubrication as it is less abrasive and It will give the pieces more durability ir at least a chance to survive. -Try to place the gear and the belt in the center of the axis, that way the pressure will have a better distribution over It. -I think 3d printed bearings mayor work. I mean those that are made on a single print and already come asembled. You may need to print them on a diferent material such as nylon. Anyway keep on with this project and sorry if someting is hard to understand, english isn't my first language.
I think in addition to bearings, you'd really do well to add a idler pulley to increase belt wrap around the drive pulley (which will subsequently also increase wrap on the driven). That way you don't need to run so much tension, which is really what lead to this failure.
I would really love to see you design a 3D printed bearing. Bearings are pretty simple, I'm sure alot of people would say its impossible, but if you used a decent weight grease inside, you should be able to make a decent bearing. I wish I had some cad software
As you said, You had some slip on the belt at the drive pulley, Well you use around 20% of the teeth. I would have added 2 bearings above and under the pulley so the belt will get around 50% use of the pulley. This is how i mean, The 2 dots are the bearing and the (o) is the pulley [ : o ] More grip and more torque can be applied! But cool and funny build :D
Bearings will be the answer, because what your doing with the both plastics binding is in affect your plastic welding I know because I used to make float switches and that's how they were put together, looking forward to seeing it run fully nice job
If you want to keep it plastic use delrin. It is designed to be used as a bushing material for metal and or plastic contact. Very slick! Almost feels like Teflon.
You can melt a candle and mix in the graphite powder. That will stay smooth and fills holes a lot better and keeps the stuff in place. My guess is that the plastic layers left enough room to swallow up the powder and make it useless.
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1:08 When your crush gives you a compliment
AHAHAH
Joel needs to make that a gif for us all to enjoy.
7 Sage Labs yes he does
Print the axle and the bushings with iglidur, this could work out quite well ;)
imitation is the greatest form of flattery relatable
This was awesome. Maybe replace the belt drive with a gear drive. That way the force isn’t pulling on the axle. Also consider a 3D printed ball bearing design for the axles like the ones used for Filament Spools. It should spread out the surface contact.
agreed... most rc car kits do it this way. team associated RC-10 has since the late 70's and it runs phenomenal.
Using nylon bushings might work as well. Although heat might still be a concern, at least nylon shouldn't chew up the PLA shafts.
Mount the drive gear and belt in the middle of the axle. This will distribute the pressure evenly. Using a bearing will only solve part of the problem. You need to distribute the force evenly. This is why in cars the transfer case is in the middle of the rear axle.
the problem with gear drive like stated in a previous video is that the motor's torque would destroy plastic to plastic gears. He could swap from the GT2 belt to a sprocket with a chain, but that would add more weight and also change the top speed of the RC car depending on the sprocket gear ratio..
@@toyotaboyhatman keep in mind, those are injection molded nylon. Also, keep in mind the weight of this model! If anyone has the exact mass, pls post it, but I think it was north of 20 kg BEFORE the motor and electronics were added!
That is completely wrong belt standard for that application, atleast go for 11mm or 15mm with. When it slips its always on the motor pulley since that has the fewest theeth that enganges. Its possible to run 2-4kW though a printed teeth pulley when done right :) Also with a slightly larger motor pulley you wouldn't need to overtighten the belt, and belt efficiency would be a lot higher. (For everyone that wants to learn about printed pulleys check out Tom Stanton's ebike on YT).
I was thinking myself the belt looked a little thin
Also a different axle design might worth a shot. This fletened one is simple, but it has stress pionts, where a lot of heat is built up.
It would be much better to use 3d printed gears - they don't need tightening
Mount the drive gear and belt in the middle of the axle. This will distribute the pressure evenly. You need to distribute the force evenly. This is why in cars the transfer case is in the middle of the rear axle.
Widening the belt will only solve part of the problem. As Joel said the belt wasn't slipping it was the poorly distributed force on the rear axle bushings.
@@Scott_C that wouldn't be that big of a problem if they used a method which transfers torque more evenly.
Or just make the axle completely round at the bushing.
@3D Printing Nerd : 6810 bearings would fit for your rear axle. These are sized: 50x65x7 can be bought for a few dollars a piece from ebay.
Silicone grease instead of graphite powder.
You want to find Super Lube, it's what we used on the RC cars back in the day, and of course bearings.
www.amazon.com/Super-Lube-21030-Synthetic-Grease/dp/B07HR46FKV/ref=sr_1_4?ie=UTF8&qid=1545073686&sr=8-4&keywords=super+lube
use heavy ball brearing grease and stop fooling around. you cant expect any lubrication if the surfaces arent even smooth. No amount of grease will work if you have sandpaper against sandpaper
or Tamiya Anti-Wear grease works well, too. Heck, Tamiya RC cars still runs on plastic and metals bearings for all I know ^_^
molymulebdeum greaseworks great for pitted surfaces it has plate lits that fill in he microscopic dents
Heavy ball bearings can make a joke with this conctruction... IMO it's better to print some decent plastic bearings. With sizes where the rollers will not be micro-sized. And I could place two pairs of identical plastic bearings there. A lot of space. It will load off that axle good. Plus some good lube and it's done. Will not work on high speeds of course but these bearings will be lite-weighted and it's important IMO.
But need to work with nylon or PETG (at least).
you didn't get heat death because you went so slow. you will need bearings for the front once you get that thing moving at any kind of decent speed.
Agreed. The friction at running speed will destroy the bushings. But It will be fun to watch the front brakes slam on when he does drive it!
You need basicly every part proper made to drive it at any decent speed, plastic tires don't have grip, decent suspension and shocks, stronger axles, its fun that its possible to make, but to drive a decent car at that scale.. Think XO-1 or Shredder.
The bushings... oh... I facepalm here... actually I've didn't believed that these are not bearings... before he cracked up them. Badly printed bearings can be melted too... But not so easy and quickly. The 3dNerd did destroyed a good axle (a lot of plastic) to prove himself that bushings are not acceptable here :)
Here you can see a real excited Nerd in its natural habitat. 1:08
Love u Joel
1)If you designed and 3d printed a gearbox for the motor you could then use a drive cog on the rear axel and reduce the loading created by the belt tensioning making the plastic parts last longer.
2) You could play round with printing bushing's with different materials, you could set up a jig in your workshop to see which one works best and last longest.
3) I know you are going to try keep as true to the original as possible but it doesn't surprise me you are finding you need to reinforce certain areas. The bigger motors tend to have more torque and also weight doesn't tend to scale particularly well so while it might be 4X scale i am guessing you are more than 4X the weight?
Weight tends to be a function of volume and therefore cubic. So, 4x4x4=64 x the weight.
Yeah he could contact "gear down for what"
@@martindinner3621 32x
@@Spooglecraft 4x4x4 is 64
why bushings? 3d-printed bearings of similar sizes are easy to make (there is a constructor on Thingiverse).
Been waiting for this video since MRRF2018. So happy to see it finally moving under its own power. Well done!
i just don't see the whole point of keeping everything plastic. Bearings are ceramic/metallic for a reason, and the belt system looks highly unprofessional. This project would've been more impressive, (not trying to undermine it) if some actual engineering calculations are done, instead of plain scaling up of a model.
the channel is 3D printing nerd... not professional RC Nerd... the point was to scale it up as much as possible, 3d print everything possible, and see if it would work. it did. now, he is making some changes so it works better. the project is 100% 3d printing centered, not to make something outside of 3d printing look professional. not too difficult to wrap your head around.
Erik Lawrence but then make it into something 3D printed that actually works. 3D printing isn’t plastic only...
I dont understand what you mean by "engineering calculations" & "unprofessional" we still have tons of heavy machinery that are friction belt driven for their powertrain with shitty plastic tensioners. There is nothing wrong with their approach hell they even have a leg up using a toothed system.
We use belt driven rc drift cars
There are plenty of motorcycles built today that use this belt style system, and some are even on the drag strip. I used to be scepticle about the idea until i saw the capabilities.
Great job Joel! It was a blast being a part of this inspiring project. =)
Actually until this was suggested to me, I only knew Open RC as 'Open Rollercoaster Tycoon'
Oh wow!
Why not print a pair of needle bearings?
You could use 1.75mm filament sections for the needles and print the races. The graphite powder would only need to lubricate the surfaces between the needles.
Good call. But pack the bearings with grease like the real ones.
At that scale 3mm filament could be the rollers.
What a brilliant way to teach design, C.A.D., material science, electronics etc., etc.
Great work, truely amazing.
Looking forward to "take 2" thank you for the many hours of enjoyment in 2018, I can't wait to see what you have ins store for us in 2019. Merry Christmas and a Happy New Year
I think you are AWESOME for just having the idea, then working thru everything while the whole world was watching.Great work!
Thank you!
This was awesome. Many things require many iterations to reach success. I love that you were willing to share the successes and failures and your plans to improve and make it better. Awesome work.
As a RC Car guy.... once you add the bearings you are going to have so much fun with this thing!!! This is an awesome and amazing project... I have really enjoyed your journey getting this bad boy to the point it is now and cannot wait to see how far you can take it... maybe you can race it one day with others that have built an 1/4 scale Open R/C. 🤔
When the rear wheels are that far apart, you most definately need a differential !!!
It will make the car drive so much easier...!!
Fantastic work Joel. Progress was made, information was gathered and FUN was had. Keep up the good work. Cheers, JAYTEE
YEAAH!! I've been waiting for this for so long!!!!!! Great job Joel.
Where's the next installment with bearings? We're already halfway through 2019 :(
Great project! I think what I like most is the mix of skills you need to finish this, designing, printing, gluing, electronics. I think it was a great idea to find experts for those sub steps and include them. If I could have wished for something, than it would have been a deeper look into the electronics.
I think using silicon grease would have been better than graphite..but a full metal bearing would be better (danco in plumbing at lowes)
Close, I spent 1 year in a 3d print airplane, it flew 3 seconds, and I am back to the next iteration, you cannot work in engineeging if you are not embracing failure as a learning process. Thanks! good luck with the bearings! wish me luck with my project
I completely agree, the belt is constantly pulling against the bearing causing excessive wear on the PLA bushing. If you look at the bushing it should look like an oval where the projective plane of the oval is parallel with the pulling force of the belt. The use of meshed gears would help to alleviate this as it would remove the tension of the belt. However there will be the constant tension of gravity exacerbated by heat on these PLA parts.
The solution you propose should be "good enough", however if you want to run this at any speed for longer periods of time, but keep as much as this car PLA, then you need an inner and outer bearing surface where the parts meet and are under a friction load.
Great show!
IT'S ALIVE!!! Amazing job 3DPN.
From an r/c guy, dump that belt setup. It's going to put too much stress on the axle as you found out. Print two carrier gears, rework the piece that mounts to the axle as a gear. Then print a cover to help keep everything aligned properly, and test again. Another reason to switch to gears is to control the possible speed the car can go.
Awesome!! - we all knew you were going to need to iterate the design especially for PLA on PLA and you were very clear about this. Can't wait to see the next run - hopefully at MRRF 2019.
This is great, awesome to have the progress videos, looking forward to seeing how far this project will go!!
When the belt slips the car sounds a bit like a real f1 car
I was nearly giddy when I saw the thumbnail then I felt do, so bad for you when it started having issues so soon. It moved! It's amazing in that aspect. I have been so enamored of this project. Why not go sith a wooden axle? I know you wanted to do as much of it out of PLA as possible but you used other materials when necessary. Why not step back and replace the axle with wood or metat. . . or even a different plastic like nylon that will resist the temperature? Cannot wait to see it really open up! Best wishes for the holidays to you and your family, Joel!
Honestly it will be fine with a plastic axle. What it needs are metal bearings and a wider drive belt.
It's great to see it moving! I'd say the belt was slipping because the bearing was seizing. Friction welding can happen from high pressure or high speed. If this thing had long-term use in its future, it just needs bearings.
Ayy it drove !!! Super cool. Can't wait to see improvements !!
Such an amazing project Joel!
Next the FK1, open RC project.
It didn't even work lol
@@AG.Floats sure it did. Maybe it did not do what you wanted, but it moved under it's own power. That is a win to me. :)
Joel love that it worked. Happier that you are going to try to fix the issues. You know that hole in the back is killing me though because I want to make it shoot fire!!!!
I understand wanting to make as much of this out of plastic/3D printing material as possible, but would it be possible to change up the wheels to either be more rugged or even just replace them with rubber tires so it has better grip? That way you should be able to go even faster without worrying too much about loss of traction and spinning out.
Put a steel pipe, as a bushing over the affected area.
Brass is better
That's not the point
or even make plastic bearings, I have seen that they print the balls and the inner and outer raceways all assembled. I do agree with you, that a real bearing would be much better than a plastic one. Especially if they were to add weight to that car.
would work ifu made both peices out of a steel pipe
With bushings you will always grind down the softest material in the mix, which in this case is always plastic.
I love that you showed the problem area. Looking forward to the next revision! I hope to see it zoom pass the camera in the next video! I love that an iPhone was used to film that.
Some tips:
1) try bushings with different materials
2) try 3D printing bearings - this works (i can send you the stl if you give me the dimensions: D_out, Din, heigt)
3) the GT2 belt is rubbish - they are 0,75mm high - so if your belt is becomming ~2mm longer or the distance betwen the two axis becom ~1mm shorter they might skip as you experienced. therefore i woud use some biger belt ore chain -> bigger teeth means that you don't need that much tension therefore the bushings shoud work better
I second the printed bearings! Needle bearings would work best. Spread out the load. Oh and pack them with grease.
I waited so long to see this run, I hope you fix the little problems. Beautiful car
As you state in your postmortem. It was the pulling of the belt on one side of the axle which caused the high pressure on one side of the drive train.
Mount the drive gear and belt in the middle of the axle. This will distribute the pressure evenly. Only using a bearing will only solve part of the problem. You need to distribute the force evenly. This is why in cars the transfer case is in the middle of the rear axle.
It’s alive! Congrats! What a wonderful maiden voyage on such a cool undertaking. Or is it an “upscaling”. IDK. I had a thought, is there any advantage to swapping the rings or the axel for 3D printed nylon or some higher heat tolerant filament? A bearing would be the most ideal though for sure. So fun to see it move in any case. Great job Joel.
This is so cool I can't wait to see it fixed up and running again
How about a 3d printed chain and sprocket?
Dude! This was awesome! Can't wait for the next stage!
Guessing this is the last video in the series so far? Loving it, just got my first 3d printer and it's not quite ready yet, but I'm super excited and loving your stuff.
Are you just stuck on finding the right size bearings?
Dude...just printing that thing at that scale is an awesome accomplishment. You'll get er all tuned up!
Just awesome! Looking @ you guys (and your enthusiasm) makes even me feel like a kid testing his new toy. Love it! Greetings from Belgium ;-)
The huge size difference between the two pulley wheels means not many teeth are engaging on the motor's pulley. I think you need an idler wheel to push the loose belt down and get more teeth engaging with the pulley on the motor, and might have to relocate the motor a bit to accommodate that. And as an added bonus you can make the idler wheel adjustable and/or spring loaded so you can solve the belt tension problems.
So awesome seeing it move! If you are going to stick with belt drive, a spring loaded idler pulley to tension the belt might let you get away with less tension and adjustments. It can increase the belt contact area on the pulleys for more grip. You would end up with another pla on pla friction spot. Snowblower auger belts use this design. (can you guess what I fixed recently?😂)
Thanks for reassuring me that I wasn't going mad when I thought I saw Barnacules (Jerry) in the mix! I'd love to see the two of you collab more.
This is an amazing build. Love watching your progress with it.
You should add a halo in the next episode!
Dude the RC car geeks know what they’re talking about. I’ve worked on a few large RC cars. My favorite was the XMAXX truck
Cant you buy igus bushing filament?
After I watched this video I saw what you need sitting above my desk. Bearings from an old project. I'd be willing to donate them if you can make them work. They are 30mm on the inside, 42mm on the outside, and 7mm thick. They are brand new and I have loads of them. They are usually used for bicycle hubs, so they're pretty cheap common bearings. I totally get the desire to make as much as possible 3D printed, but we can't defy the laws of physics for long. If you need a different size I have a connection. It does take a few weeks to get things shipped, but I can get anything that's commonly made.
Hardly a failure as it moved and worked. We all learned a lot too. 👏👏👏
Every bursted bubble has a glory!
Each abysmal failure makes a point!
Every glowing path that goes astray,
Shows you how to find a better way,
So every time to stumble never grumble
Next time you'll bumble even less!
For up from the ashes, up from the ashes, grow the roses of success!!!
("The roses of success" in chitty chitty bang bang)
this is my go to when something I worked on didn't go as planned. This isn't a failure only a momentary set back!
Did I see Bill there on one camera?
yep - and Barnacules too
*waves*
I am SO glad you put the car driving part at the beginning. If I had to wait through a long video for that I would have unsubscribed hahaha
Good to see it finally moving, glad you're getting some real bearings on it. I have to wonder if 3d Printed roller bearings would do a nice job. Good luck.
Once you work out the Belts/Bushing/Axel. PLEASE try a couple layers of plasti-dip on the wheels like tread for grip. and MORE motor power.
Awesome build!
But if the wheels grip you can't drive sideways.
Sideways = cool but slow. Real F1 aren't "supposed" to go sideways
That sounds like a problem with real F1.
Thoughts:
1. Mount another gear for the belt to the axle mount *behind* the axle. That way, all of the pressure from the belt will be balanced--up and back at the bottom of the axle gear & down and forward at the top of it. Yes, you won't have as many teeth engaging, but there won't be uneven pressure on the axle. Alternatively, use the current belt setup and add a second belt going to the rear (idle) gear. That would maximize the number of teeth engaged while also completely balancing the forward and backward forces on the axle. (Now that I think about it, to perfectly balance the forces acting on the axle, both the motor and idle gear should be mounted *below* the plane of the axle, as gravity will cause the mass of the vehicle to press the axle against the top of the bushing. By the belts pulling *down* on the axle, there would be less pressure against the top of the bushing.)
2. Use *two* bushings with a tiny gap between them that matches up with a reservoir built into the axle mount that holds a large quantity of graphite. That way there will be a constant source of lubrication.
3. Would a carbon fibre or metal-infused filament be considered cheating? If not, matching axle and bushing surfaces should reduce friction.
4. Mating surfaces should not just be sanded, but *lapped* until they are mirrors. That alone will reduce friction by an *incredible* amount.
Hope this helps!
I’m willing to bet that the pla axle is going to be an issue even with a metal bearing. That thing has to be bowing under belt tension. Still an awesome project to undertake and I can’t wait to see where it goes from here. Kudos 3D Printing Nerd.
Brushless motors have a lot of torque so I suspect his gear ratio was way off for the motor. A much bigger pinion pulley and smaller spur pulley will give better tooth engagement on the belt so it won't need to be so tight. On racing RC F1 cars we are geared at about 1.8:1 with brushless motors. This one looked more like it was 50:1. Also if you use a coarse tooth instead of a fine tooth you'll get no slippage with only a slight amount of tension.
Great work guys. Like you said Joel, not a failure, a learning experience.
1:08 Little kid trying to contain his excitement on Christmas day
Such an ambitious project, great job
Next challenge should be :
1. Pin bearing /w automobile grease
2. Open Differential
3. Plastic Suspension (maybe leaf sus would be easy to build?)
Lol I’d love to see that. Great work dude
Have you considered just skipping the problem altogether and going direct drive put the motor where the axle is and mount the wheel directly to the motor no friction issues :-)
then it wouldnt be a scaled up openrc... it would be a scaled up car based on... thats no fun at all.
This was awesome buddy! Progress!
Suggestion for once it's actually going, drag strip race against a Tesla! Awesome video, Joel. Glad nothing catastrophic happened.
Yes I've been waiting so long to see this video
It shows you guys arent engineers....
ya know, you learn more from mistakes than from success
@@linecraftman3907
I never had to jump off a cliff to learn i can fly. Some things are obvious, more if you know PLA isnt very heat resistant, it heats up quickly, and graphite only works on smooth surfaces (like inbetween the plates of a lock). Graphite is a thin powder, what makes you think it will stick and lubricate a piece which has grooves bigger than the graphite particles themselves?
It shows you're an illiterate buzzkill...
@@BemerLuis
I didnt kill the fun, they did by making the car very poorly so much it died mid testing. Also its exactly because im not illiterate that i can point out the obvious and blatant faults in their design.
Laharl Krichevskoy actually it’s because you’re observant that you noticed, you’re still illiterate, and this project is the point of trial and error. If they had the perfect design then it’d be a one and done video. And obviously you have no engineering prowess, you’re just a buzzkill
“Wheels on the bus go round and round...” good work!!!
The greatest thing about this is that we're learning with you. Sure there are some that know a lot more but just being told the answer isn't as fun as working it out for yourself. And if you can't, THEN you can't listen to the experts.
Suggestion get rid of the belt drive, the belt needs tension to work, and creates high stress areas. Points of high friction in other areas. Gear drive can provide a lot less friction, you don't need to apply stress, your gears can float with proper adjustment. You can also control your speed by the gear ratio. Also what about plastic bearings? Yes I know the insanity of making them, but the benefits would be great. Just a thought.
Awesome work Joel! 👍🏻👊🏻 Perhaps besides the addition of the bearings and tensioner, using a toothed belt would help to reduce the amount of overall tension required to drive it without slippage.
I use 3d printed parts made froom Aprintapro PLA and PETG in my RC Scale Crawlers, they hold up to extremely rough handling on demanding trails.
With the right lubrication and print settings you will be able to make it much more resiliant. I'd change the geometry of the drivewheel to use a coarse timing belt and use PETG on the bushings(this material tends to slip better on other PETG parts than PLA. you can drastically reduce the stress on the pully by adding more stages of transmission to increase torque. a gear ratio o 1:25 is considered aminimum in RC
Great build! Looking forward to the 2.0 version! High five
Joel: What might also help with prolonging axle life would be if you made little crescent sections for where the axle rides in the bearing in order to make it a full circle there.
If you're going for 3d printed bushing possibly use acetal/POM/delrin. It has great low friction and wear resistance. I wonder how it would hold up with a pla axle rubbing against it.
What about using the gear bearing spinners for your bearings. I spun them up really fast with a drill and they stayed cool. I feel they would hold up for a while. I am talking about the same gear bearing Prusa has as a test print. Might have to scale it up due to your axle being so large.
Such a fun project Joel! High five great work!!
Joel you need to go full bearing in all of the axles, I know you can make it move with just bearings on the rear, however I want to see this run as fast as it possibly can for as long as it can. You and many other have demonstrated that 3d printed parts can go a long way, however they have a limit on what they can accomplish by itself, doing a combination of 3d plastic and metal components is the best route. Another suggestion is to change the rear axle to something made of metal if possible like a threaded steel pipe :D. If I can do anything to help let me know.
I love how much your mouse-scale formula e squeaks.
I think people talking about plastic bushings welding to the axle were under the impression you weren't going to limit the power of the motor all the down to 15% . I personally have no clue what's going to happen
Hi great video
Let me tell you some ideas i came up with while watching the video.
-Use silicone grease for lubrication as it is less abrasive and It will give the pieces more durability ir at least a chance to survive.
-Try to place the gear and the belt in the center of the axis, that way the pressure will have a better distribution over It.
-I think 3d printed bearings mayor work. I mean those that are made on a single print and already come asembled. You may need to print them on a diferent material such as nylon.
Anyway keep on with this project and sorry if someting is hard to understand, english isn't my first language.
I think in addition to bearings, you'd really do well to add a idler pulley to increase belt wrap around the drive pulley (which will subsequently also increase wrap on the driven). That way you don't need to run so much tension, which is really what lead to this failure.
6S Pulse battery. Damn guys that is a hulk of a power source!
I would really love to see you design a 3D printed bearing. Bearings are pretty simple, I'm sure alot of people would say its impossible, but if you used a decent weight grease inside, you should be able to make a decent bearing. I wish I had some cad software
World's slowest to scale RC car in the world should be the title.
As you said, You had some slip on the belt at the drive pulley, Well you use around 20% of the teeth. I would have added 2 bearings above and under the pulley so the belt will get around 50% use of the pulley. This is how i mean, The 2 dots are the bearing and the (o) is the pulley [ : o ]
More grip and more torque can be applied!
But cool and funny build :D
Bearings will be the answer, because what your doing with the both plastics binding is in affect your plastic welding I know because I used to make float switches and that's how they were put together, looking forward to seeing it run fully nice job
Nice project! Realy liked it.
3D Printing Nerd....Which 3D printer are you using to print those parts?
I cant remember if you DIY your own 3D printer?
Finally!!!! Was waiting for do long
If you want to keep it plastic use delrin. It is designed to be used as a bushing material for metal and or plastic contact. Very slick! Almost feels like Teflon.
Wow Jerry even was involved. Good to see him
You can melt a candle and mix in the graphite powder. That will stay smooth and fills holes a lot better and keeps the stuff in place. My guess is that the plastic layers left enough room to swallow up the powder and make it useless.