Building R2-D2 Part 8 - First Steps! V2 Legs & Mark 3 Foot Drives

[@Rchelicopterfun]

Making R2-D2 Video Series: - Introduction to a DIY R2-D2 Build: kzbin.info/www/bejne/npzOhJSdidh_jrs - Part 1 Making the dome: kzbin.info/www/bejne/fpK9aHR4oM2qpJo - Part 2 Painting the dome: kzbin.info/www/bejne/n5_SonhnbrR3i7M - Part 3 Dome lights & holoprojectors: kzbin.info/www/bejne/nnW1aq1nhaZ9iaM - Part 4 Dome Completion: kzbin.info/www/bejne/hp_NdKWCoa-nn8k - Part 5 Mark 3 Body Assembly: kzbin.info/www/bejne/o2e5iadsi6yNacU - Part 6 R2 Sound System Basics: kzbin.info/www/bejne/mYuWpImPqJyHb6s - Part 7 R2 Electronic Basics: kzbin.info/www/bejne/d564po1-aLp7jsk - Part 8 R2 Legs & Foot Drives: kzbin.info/www/bejne/hn3cgH56atR0r68 - Part 9 Painting R2-D2: kzbin.info/www/bejne/e2nLYZ9qp62peZY - Part 10 Installing Electronics: kzbin.info/www/bejne/mJjCpYFsfaiMhJY - Conclusion to a DIY R2-D2 Build: kzbin.info/www/bejne/qXrTc3Rsis6airM Terminology correction: I used the term "intermediate" when describing the center gear. This is not fundamentally correct as a true intermediate/idler gear has no reduction, it's a 1:1 ratio and that is clearly not the case for the center gear in the Mark 3 feet.

[@DanielTesenair]

John, I've been binging this series, and began to print my R2 pieces last night. I just wanted to thank you very much for putting this series together. It is extremely helpful and you've done an amazing job. Even for somebody like myself, who has minimal electronics experience and NO R/C experience, you're explaining things in a way I'm able to understand. I'm sure I'll come back to this series time and time again in the future as I continue to work on this project. I'm sure I'll have some questions for you too along the way, haha. Thank you again!

[@Rchelicopterfun]

Thanks back for watching the series 👍🙂

[@lucassheridon9809]

Awesome to watch progress in the build! I’m glad you tested out the rollerblade wheels, I’ve wondered the same thing as you for a while. I won’t be building my R2 for a while (college student) but I’ve been trying to gather up ideas. Happy to know they work good in the front foot. I feel like in other builds the Omni wheels make the whole R2 drive around noisily, taking away from the magic a little. Keep up the series!!!

[@Rchelicopterfun]

@Lucas Sheridon, Yes, noise of the Omni's is another area of concern I too am wondering about. From what research I've gathered, seems as long as you use the VEX Robotics Omni's which have the softer rollers, it's okay. Guess we will know once I get them. Problem is they, like many things right now are in the realm of unobtanium. I found a place here in Canada that still had them showing in stock. Ordered them last night... We will see...

[@pauly540]

Thanks for sharing your progress. I actually printed out Mr Baddeley's 3D printed ABS omni wheels and they worked out great. Found out that microwaving each TPU omni tire (there's lots of them) for around 20 seconds before installing work a treat. The pre-made Vex brand omni wheels seem super expensive for what they are, so recommend everyone give it a try first. The miniature bearings are super cheap.

[@Rchelicopterfun]

@pauly540 - Thanks for sharing your positive experience and tips with the printed omnis.

[@Rchelicopterfun]

@pauly540 - Mind if I ask how your printed omnis are holding up long term and if you do drive on less than perfectly smooth and clean surfaces?

[@pauly540]

@@Rchelicopterfun Hard to tell, as yes, I only drive on smooth surfaces, not on bumpy footpaths. Plus I've only got a couple of hours driving time in. I like Mr Baddeley omni wheel design, as they have individual tires, so it's easy to just print out new ones and they do sound quite.

[@Rchelicopterfun]

@pauly540 - appreciate the reply.

[@bstotty]

Thanks for there laughs. So good to see how quiet the drives are!

[@Rchelicopterfun]

😄

[@ElixirGraphics]

Thoroughly enjoy your videos on R2. Keep them up!

[@Rchelicopterfun]

Thanks, will do

[@gdhall5311]

I am enjoying this series, good job John.

[@Rchelicopterfun]

👍🙂

[@larrychamel]

Fantastic work, John! It looks incredible!!

[@Rchelicopterfun]

🙂

[@AlaskaMan420]

You inspire me. Thanks.

[@Rchelicopterfun]

🙂

[@goofballproductions7629]

Been waiting for another video, YAY!

[@Rchelicopterfun]

🙂

[@natepropes]

Loved the whole series, it has really helped me in getting mine assembled. At about 90% printed and working hard on sanding and finishing. I'm getting ready to print the TPU. What TPU did you use for the tires?

[@Rchelicopterfun]

Hi Nathaniel, glad you are enjoying the build series and that you are nearing the end of your own R2 printing process - never seems to end does it. As for the TPU I used, nothing special... 3D Printing Canada's generic TPU. No idea if it's rebranded from something else, but I think 3D Printing Canada makes their own brand filament in house.

[@TheMrRatzz]

Ive watched through this playlist several time and love it. Great information, and fun. I have subscribed to Mr Baddeley on Patrion, but god knows what files i need to print. Is there a list anywhere that you used? Any help would be awesome... 👍🏻

[@Rchelicopterfun]

I used the Printed Droid Print Guide for the primary parts list as I mentioned & link to in the very first video of this series (The Introduction Video). That said, there is of course no specific one size fits all file list because it depends on what options you want on your build, what specific version you want to print and how you want to build it. There are endless options on these builds so Michael has kindly provided lots of files. Even depending on what size printer you have will dictate what files will and won't fit. His instructions also cover what specific files are used for certain assemblies. I also spent hours looking at various files in my slicer program after downloading to determine which I wanted/needed to print based on my specific build and requirements. Enjoy your R2 build!

[@TheMrRatzz]

@Rchelicopterfun thanks for the reply John... I've just downloaded those files and have the Sovol 6 plus, but it's just that all the files I seem to find seems to be all over the place. Some cut files here, some in other folders done by someone else. I'll get there! I plan to start in January here in the UK, and have a full time job, so thinking 9 months to a year if things go to plan. Your build is stunning John, one of the best I've come across. I'd be happy to have a build anywhere near as close! Thanks again John. You may hear from me again! 😁👍🏻❤️

[@junebugrc3015]

Awesome man !

[@Rchelicopterfun]

Thanks for the visit

[@garygonzalez2274]

Is there a published file for the front foot block that the casters mount into?

[@Rchelicopterfun]

Not that I know of. I made mine first out of a block of wood to test the concept & fitment, and when I was happy with the size, height & fit, then quickly made up the same size block on Tinkercad to print out for the final version.

[@AdamKirsner]

@@Rchelicopterfun Hi, I love the series. I am working on my R2D2 right now. Is there a way you could share the center block file.

[@TheMakersCave]

I'm curious. I just started printing my pieces for an R2. I've built other robots using Jazzy chair bases and they work great. I too use a SaberTooth controller, the best IMHO. You say you're worried about tire rubbing on floors when turning. I always put the SaberTooth in tank mode so it turns smoothly and within it's own space. I notice a lot of builders doing what we call "drag turns" too. Is there a reason why this type of control is preferred?

[@Rchelicopterfun]

Doesn't matter what mode the motor controller is in, when the center point of the turn radius is between the front drive wheel and back idle wheel, you will get wheel scrub. No way around it other than using a rear idle wheel that also allows side movement to follow the different radius such as the recommended and proven Omni, a small castor or don't use any rear idle support wheel which some apparently are doing without issue.

[@TheMakersCave]

@@Rchelicopterfun Okay, now I get it. Just started my build and didn't know there was idle wheel. After some video watching I think I'll go the caster route.

[@zombiehunter1152]

Great job to get him moving, I just can’t get a Sabertooth 32 at the moment so your so lucky you have one.

[@Rchelicopterfun]

@Zombiehunter115 - Yes I had a hard time finding one too. Robot Shop were both showing restocking by mid December last year, but they never got any in and now are showing end of March which isn't too bad if that time frame holds. I located the one I got back in January at a place called SuperDroid Robots, but they are out of them now too I see. The folks at Robot Shop recommended the Cytron SmartDrive Duo 30 when I asked if they had anything else that would work for an R2 build of similar quality and specs to the Sabertooth 2x32 or 2x25. amzn.to/3JdYLHI The specs are certainly good as is the price. The only small concern is the switching frequency of 18kHz vs. the 30 on the Sabretooth. I very much doubt it would be detectable. I know I can't hear an 18 kHz tone, but some people likely could pick up on it? Another dual motor controller I heard about is the RoboClaw 2x30A. I never looked into its operating specs however so don't know much about it.

[@zombiehunter1152]

@@Rchelicopterfun thanks but even their out of stock now too. I have got a Sabertooth 32 on order from dimension engineering but their even saying the end of may, so I guess I have to wait. Your R2D2 is coming along nicely, it’s nice to see him driving around.

[@nevilenobody606]

Hi John what size are the center foot casters? Are they standard office chair casters with rollerblade style wheels?

[@Rchelicopterfun]

Yes, standard office chair roller blade wheel type castors you can find everywhere. Think they are 3" but can't recall for sure. I', sitting on a set right now and they look about 3".

[@nevilenobody606]

@@Rchelicopterfun Thanks! I will most likely go your route to save on the cost of using omniwheels for the center foot. It all adds up real quick!

[@coz3d]

Love the video series! Where did you get the center wheel adapter for the casters you used? I want to try that instead of omni wheels.

[@Rchelicopterfun]

I made it. First on tinkercad to see if it would even work, and then made the final block from a piece of hardwood.

[@coz3d]

@@Rchelicopterfun Appreciate they help! That's what I'll do then!

[@douglas71322]

Great video!!! I have a situation where the motor shaft is thinner than the gear. What kind of shim have you used (if applies)? Thanks a lot!!!

[@Rchelicopterfun]

No shim/s used. Drive gears were a nice tight fit on the motor shafts of the foot motors I used.

[@douglas71322]

@@Rchelicopterfun thanks a lot!

[@28apex]

Hello John I don’t know if I just didn’t see but are there files for the legs that a sliced ?

[@Rchelicopterfun]

Yes there are sliced leg files. That is what I used on my build.

[@TheRealMisterJ]

Hey hope you can help! Running the exact same setup as you but my e100 motors don't seem to have enough torque to get R2 to move properly, I have to give him a little push and he tends to stop and have the motors make a grinding sound..

[@Rchelicopterfun]

Several possible reasons come to mind. Your Motor Controller is faulty or net setup correctly. Using 24V motors with a 12V power system. Using too small wire gauge. There is mechanical binding in the gear train. Or perhaps a combination. Of course without testing actual voltage, voltage drop, current draw and motor controller output with a DMM, these are just guesses.

[@Drowiz]

Amazing work John - center foot casters is great, more quiet than omni's, and I think you sold me on it - did you just use the OmniFrameTop.stl file as-is, or expanded it a little on the Y-axis to adjust for the height? Thanks for the videos, you have great content!!

[@Rchelicopterfun]

Like several other _special_ parts in my R2 build, I designed this front foot caster wheel block in Tinkercad. This one is just the first test unit with a low infill, but fits the ankle & shell fairly well... still a little size tweaking however. There is one potential downside to using these larger rollerblade office chair casters that you should know about. They can hang up on each other if they rotate toward the center both at the same time. It's very doubtful they ever would do that - they follow each other very well, but it's something to consider and experiment with. I've had no issues, but he has not ventured outside onto rougher surfaces yet - that will be the real test. In short, I still may have to go with VEX Pro Omni's in the front, but so far, these are working great.

[@Drowiz]

@@Rchelicopterfun Thanks for taking the time to answer - I didnt realize they can run on each other, but I'm only planning to roll indoor on hardwood/tiles so that should be fine. I may as well get to Omni wheels down the road, will be attempting to print Mr Baddeley ones for the side feet and see how I like them. Cheers from a fellow Canadian!

[@GregsnBacon]

@@Rchelicopterfun have you uploaded the stl files anywhere for the centre foot caster wheel blocks? I'm interested in using a similar design, thanks!

[@pierrewhorley9603]

Hello John. What drive motors did you use? I had to modify my gear to accommodate the smaller drive shaft, but it's not 100% and I'd like to get it sorted.

[@Rchelicopterfun]

@Pierre Whorley: I cover electronics including the specific motors I use in the R2 electronics video: kzbin.info/www/bejne/d564po1-aLp7jsk

[@wolfman6770]

Where can i find the file to start printing out the parts this looks amazing that i want to try building a Droid I feel so inspired

[@Rchelicopterfun]

Links in description.

[@mlw9195]

I have a question where’d you source all the material you need like the wheels and the electronics?

[@Rchelicopterfun]

Where? Lots of Google research & R2 Builders club reading. I have links to all the components I used in the descriptions of each video covering the specific topics in this 12 part build series.

[@multimood]

Could you put a castor wheel behind the drive wheel to get rid of tire scrub?

[@Rchelicopterfun]

They would have to be very small castors (likely not much larger than 1" dia.) as there is not much room in those back feet behind the drive wheel and shell; and castors need lots of room to pivot around their centers. Tiny castors would then get caught on any small surface crack/similar. 3.25" Omni's are clearly the best/only option in these 3D printed feet, unless one wishes to redesign the entire rear foot drive.

[@jeffreypajela1724]

Hi John, I'm working on the foot drives at this time. I've noticed on the baddeley files I found just the right foot only no left foot files might they be somewhere else?

[@Rchelicopterfun]

Both sides were in the Mark 3 foot files I downloaded.

[@garyowen3743]

Which legs did you print John I see there are two lengths, shorter ones or the longer ones if in the future you want to upgrade to the 2-3-2 version.... With regards to omni wheels learnt my lesson in the past with another none rc project trying castors, didn't work, so I sourced some rubber hard wearing omni wheels in the UK, they vary so much in price and with shopping around can find some at a reasonable price, eBay tended to be expensive for some reason....I decided to bite the bullet looking at the final weight variant of R2 I would buy the 3.25 omni wheels than attempt to print them, parts are getting hard to find in the UK for electronics especially the sabertooth board, still waiting on Prusa at present to catch up on production so still waiting on my printer, I have really enjoyed following your journey on this build, I was looking for another hobby as well as rc helis that would occupy my mind during winter months and rainy days, this has given me a good enough reason to justify a 3D printer, will you be doing a final video of your radio programming how you set your mixes and switches and controls up in the radiomaster, great work really enjoyed the R2 videos

[@Rchelicopterfun]

V2 Short - I have zero desire to have 2-3-2, not to mention R2 is already top heavy and having the center of mass even higher off the ground seems problematic IMO; but what do I know 🤔 Yep, I very reluctantly ordered two VEX 3.25 Omni's the other night. Unfortunately, like many other items right now, the VEX Omni's are also in the realm of unobtanium. I did however find a place in Canada that still had some showing in stock. I'm sticking with the roller blade casters in the front for now. They are so smooth and quiet and are much more robust which I need for my environment. Might do a basic control video at the very end of the project just to show the basic controls, but won't be going over every aspect of OpenTX setup because it will be vastly different for every build & individual's preference. Besides, it's easy - there is no complicated mixing or output curves, nothing like a helicopter setup. Each channel has it's own input and output - nothing complicated at all. Of course, that's the great thing about Open or EdgeTX, you can make it as simple or complex as you want it to be. I can only imagine the automation we could give an OpenTX controlled R2 with creative logical switch programming.

[@bluebeast440]

Instead of omni wheels, couldn't you use casters there also? They would be durable, and yet would reduce the scrubbing. Or there might be some physics thing i'm not understanding?

[@Rchelicopterfun]

There is not enough room for casters in the Baddeley Mark 3 feet. To use even a small caster, the back 1/3rd of the foot would have to be cut out and the foot shell made thinner along with coming up with a new mounting system.

[@bluebeast440]

@@Rchelicopterfun Awww.. it's sooo close though lol I see the motor would probably be in the way of the caster spinning also. Yea, it would require a different design for a rear caster, but again, I wonder if it would even help. If a caster would indeed be a better option than an omni for rough terrain, a person would just change the 3d model design to accommodate it. I'm sure you're not ready to experiment since you have it already built.... but it might be an option for people starting out. The caster could also be mounted centrally and not offset like the current wheel has to be. Just thinking out loud lol

[@Rchelicopterfun]

Yep it would require lots of time, work, testing, and experimenting with different size casters & wheels to get something that works. Or... folks could just use a 3.25" omniwheel that the foot was specifically designed to use and not worry about all that 🙂

[@bluebeast440]

​@@Rchelicopterfun Luck favors the brave :D

[@RealScottPowers]

Just wanted to add that if he's always going to be in 3 leg mode, you don't need the back wheels at all. I've tried everything from omniwheels to casters to omniballs. My favorite solution was the omniball but lifting them about 1/2 inch from the ground, so that it's only used for occasional stabilization (as if you can stabilize a moving tripod). Many of the filming droids didn't have rear wheels at all either.

[@JediAlliance]

Maybe there's a way to add some type of slip differential to get rid of the drag? hmmm

[@Rchelicopterfun]

@Mike Roy. Unfortunately, it's not a differential wheel speed issue (both left & right drive wheels are completely independent after all and fully differential). It's a sideways wheel scrub issue. Easily and totally cured by fitting rear Omni wheels (Part 9).

[@JediAlliance]

@@Rchelicopterfun after I wrote this I realized that you resolved it lol. Thanks. I just found this build series and I’m seriously considering starting. I’ve been wanting to build an R2 for many many years and now that I own a Ender 3 S1 I think I can actually do it. It’s very intimidating but maybe I should just do a static one ? I actually have been in the RC hobby for 20 years but not sure I want to tackle that end of it. What do you think ?

[@Rchelicopterfun]

@Mike Roy, Only you know your comfort level with a build like this and how much you want to take on. One thought however... You can always do a static model to start with and add motion later on. Nothing saying you have to have it moving right off the bench :)

[@JediAlliance]

@@Rchelicopterfun very good point. Maybe that’s what I’ll do. I like the idea of how you said to start with the dome then get a feel for it that way. Before 3D printers this seemed like such a daunting task but it feels more achievable now

[@juniorwest5706]

Crazy 🤪👍

[@toys5355]

That’s amazing! Now, when will the maiden hover come?

[@randalcomia2492]

How did you print the legs? Is there a cut version that Im overlooking?

[@randalcomia2492]

I did overlook them I just found the files

[@tabletop.painter]

Heya buddy how did you go about doing the wheels on the front?

[@Rchelicopterfun]

Not sure what you're specifically asking? I purchased the castors, measured them up to find their height, pivot offset & shaft diameter. I then printed up a test spacer/mounting block, slid the castors into the block and mounted it to the front ankle to test.

[@Toy_and_Prop_Masters]

Hi John, EXCELLENT WORK! I subscribed to your channel as well! I joined the Mr. Baddeley's Patreon Page and paid the $5 monthly membership and downloaded the parts I needed for my R2 build. Do you know where I may find the step by step instructions on how to assemble the foot parts and dome gear? As for the done gear, I only saw the large 18" one that has the teeth inside. The small motor mount gear I did not see anywhere. Would you know where to find it? I emailed Mr. Patreon the other day but he has not replied to my email I just need the assembly instructions manual not the 3D printing instructions. Please let me know. Thank you, Ed

[@Rchelicopterfun]

@EdG407FL. All the instructions for the printed versions are in the Baddeley download files. I can't recall off the top of my head the exact file names or which folder but it seemed they were no too hard to find (granted that was almost two years ago now) and I know he continues to add more. There are so many files and sub-files for the various parts, various versions and various cuts. It can take quite a while locating some of them. I spent hours looking for some things. In fact, I recall being pretty much finished the dome when I finally found the instructions and hardware/fastener listings for the rest of the build.

[@Toy_and_Prop_Masters]

@@Rchelicopterfun Thank you very much for the quick reply. Keep up the great work.

[@ChrisSmith-il5qe]

"What the mothering ffffffff.." Lmao, I'm dead.

[@jimmihenry]

5:28 because they are quieter :).

[@GeoFry3]

I hate when I get spool of filament with a twist in it that jams it up. If you are lucky it was just a worker getting the spool tightened up and is only in one spot. If you are unlucky a machine caused it and that filament jam occurs say every 15 feet. That is the kiss of death for any long prints.

[@GunnerAl9]

Instead of hot glue for keeping the nuts in place. Grab the wife's clear nail polish and just drop a dab in the hole over the nut. Dries in seconds, super strong and won't make a mess.

[@richardraesr3482]

311👍🏻 Looks great