ISIRC10

So here is the break down. My high school is having an art show in late May, and a few of the art teachers though it would be cool if I built something remote controlled for it. It wasn't anything in particular, but I made the decision to build a replica of Pixar's Wall-e robot. I have a couple of extra servos for auxiliary functions, and a cheap 9 channel 2.4 GHz radio to control it. For propulsion, am still largely undecided, but I do have two Denso windshield wiper motors (12v) that I am inclined to use due to their high torque and low speed - probably the best thing for running tank treads. For batteries I will probably use some 3s lipos I have lying around from other models.
In terms of sizing, I have decided to make this about 1-1, with the 'bot standing 3.5'-4' tall. The main building material will be wood, with some mdf and chipboard in non-critical areas. I am trying to make this as inexpensive as possible, so I may have to get creative sometimes. Feel free to chime in with your methods and suggestions - I WILL take them into account as find that I learn the most that way. That is one of the reasons I am sharing this build (that and to have some documentation if anyone wonders how I built it)
Anyways, to get us started, here are a few pictures I will use for scaling and details.

esavagenoobie

Sounds interesting... Looking forward to how this will come out...

ISIRC10

I started the project this morning, and have gotten together the materials for the first parts. On second inspection, the windshield wiper motors were the perfect speed, although their output shafts did pose some interesting challenges. I was planning on using 25 chain to drive the tracks but mounting the sprockets to the output shafts of the motors was a bit unorthodox (the white plastic extrusion spins, the steel shaft is static!) To solve this I made two adapters out of a 1/4" thick plastic cutting board with a matching pattern. The sprockets were mounted to the adapters with bolts and that was that. I will think about mounting the motors later in the build. For control, I have a few victor ESCs I purchased on E-bay (used, very cheap) that are overkill for my application but should do just fine.

Tomorrow, I begin cutting idlers for the tracks.

electricrc68

you're one smart dude.

BKoz559

My Feedback: (3)

My kids love WALL-E. I have to admit, I like the movie too.

Some thoughts that came to mind right off the bat are:
1. Since you're trying to keep it simple, build the main with a basic wood frame and use foam board as the "skin" and paint the details on the exterior. At 4+ feet tall, it would be rather heavy if made out of MDF. Buildadditional internal framing where the drive motors would attach to give added support. Otherwise you could build a cube out of MDF, much like a speaker enclosure.
2. Are you planning to build funcitonal arms? That would make the end product more interesting but you may not have sufficient time. Again, for cost savings, perhaps use wood for the arms rather than aluminum or plastic.
3. Not too sure about the head and neck but, perhaps you can cut a "teardop"shape out of thefoam board to use as the front and rear of his head. Then use sheets of hobby plastic to wrap around them to create each half of his head. I think it would be cool to use2 Ultra Violet filters (used for camera lenses) for the eyes. You can find them on ebay really cheap, probalby $10 a pair for a generic brand. You can cutout a photo of a camera lens from a head on perspective and mount it on the inside of the filter. That would give the eyes that camera lens look with little effort.

ISIRC10

Thanks!
I have to do something in my spare time, and it just happens that my dad lets me use the shop in the basement of our house - I consider myself lucky.
I am on spring break at the moment, so progress should be rather quick. Then comes the crunch before AP exams, and by the second week of May, I should be back to building at full speed.


Sounds like you've got that part figured out! I was wondering what I would do to achieve the effect of his eyes, but I think that would be the ticket.
I hope to have the arms functioning - I will have two channels for driving, two for head movements (pan and tilt), so there will be four more channels (or more if I get creative with mixing)
For the head, I like your suggestion - I have a 4'x8'x2" sheet of the pink foam (I usually build boats out of the stuff) As for weight - I am not overly concerned, I am hoping to keep this thing under 20 pounds. I am looking to make the box out of 1/4' plywood and then adding the details in mdf and ABS (easier to sand and shape). If I need to remove weight, I have a portable router that can turn "speed holes" into an art.

rasper

man i loked that movie.....let us know and take pics once your done

ISIRC10

Woke up early today, worked out some measurements, and marked out a few parts. Then when everyone was awake, I started cutting idler blanks. They are made out of a crappy (in terms of usefulness) piece of 1.5"x8"x8' piece of pressure treated pine. I didn't really like working with this, but I also didn't want to waste any quality wood on the wheels. I wore a dust mask when I was cutting and sanding the stuff, as I am not sure what they do to the wood to pressure treat it (it was kinda greenish and ugly looking). To make the blanks, I used a 4" diameter hole saw to cut half way through the 1.5" board, and then flipped it to finish the wheel. I then enlarged the center hole from the 1/4" pilot to a 5/16" in order for it to accept a bolt and a nut. This was then tightened and chucked in a handheld drill and the blank was turned against a belt sander. I don't have a lathe, so this was the best I could do to remove the imperfections left by the hole saw's jagged teeth. Then I used a 3/4" spade bit to enlarge the center hole again, this time to accommodate the ball bearings I was planning to use. Lastly, a 1/2" drill bit made it possible to fully seat the bearings (The spade bit only removed a half inch from each side of the wheel, leaving a 1/2" section in the center with a 5/16" hole. The bearing's inner race would hit that section, so the hole had to be enlarged to 1/2").
To complete the look, I will be putting 8 3/8" holes in the idlers, to simulate bolt holes. Additionally, I will glue a mdf ring to the idlers, made from 1/2" mdf and a bit of creative hole-sawing. Note to anyone who tries to do this: mdf is not a very good material to use a hole saw on - it begins to split into layers and has to be glued back together before it disintegrates (I found this out the hard way!)
The bearings I used came from two pairs of old roller skates I picked up at a yard sale a few years ago. They were free because all of the bearings were jam packed with grease and dirt, but I cleaned them out and now they are just like new. They will spin on 2" long 1/4-20 stainless steel bolts. Hopefully I will be able to finish the idlers tonight and will post more pictures later.

warnos16v

Mate keep the pictures coming.. very interested in this.. I am about to start the same thing.. I am building a life size one nearly 1 meter tall.. its going to be in our wedding got 6 months to do it... Just started getting all the wood together and reading up on allot of tutorials online..

ISIRC10

Great minds think alike!
You asked for pictures, here they come! Today was a VERY productive day, don't expect many more of those... I finished all 8 idlers (4 per track). It was a lot of drilling and sanding, with some gluing in between. Once I had finished all of them, I picked them up all at once and became paranoid - they were heavy! Perhaps I would need to do some speed holes. In the end, I settled on 1/2" holes, drilled to a depth of 5/8". This made a significant weight difference, and I was satisfied. I am very happy with how they turned out.

Next up are the mounts for the idlers - its that hydraulic looking cylinder thingy.

ISIRC10

Last post of the day. I got the basic outlines of the mounts complete, and drilled some lightening holes in them. Once I am finished, they will not be visible, as I plan to sandwich the pine between two other pieces of wood. They are less dense and easy to shape, and they don't weigh as much. hopefully I can finish this up tomorrow and start on the bottom idler. After that, I will think about the tracks and the drive sprocket. Any ideas on how to make treads? I have a few floating around in my head, but I want to see if anyone has any better thoughts (cheaper and easier to make)

tommygun32

Nice build thread.

Just a quick question ISIRC10, do you have a pro photo shoot stage as well? Do I see 3 light sources in your pics?

ISIRC10

nah, I wish... no shooting stage for me. As of now, I am stuck with a large sheet of elmers foamboard from Staples ($12), two desk lamps with lense covers that I sandblasted (to diffuse the light) and the ceiling lights, which are garage lights. Nothing professional, and it all stows into a corner in seconds.

tommygun32

Nice set up, quality photos....

ISIRC10

Thank you for the compliments!
From experience, I know that pictures are everything for a build thread, so I take some time out to make sure that mine illustrate the process to the best of my ability.
The only downside to good pictures is everybody knows where I messed up... oh well!

There were a lot of pictures in today's update, but I was not able to do a step-by-step documentation as there was just too much to do (a lot of test fitting and aligning) for the photographs to be taken. To continue from the previous post, I took the center sections of the hydraulic rams (the ones with all of the lightening holes) and sandwiched them between two other pieces of wood (3/4" thick). This was bonded using regular wood glue, but after an hour, was plenty strong for me to router. I have a cutter that is used to follow templates, so I used that to follow the curves of the center section. This resulted in a perfect profile for the outer pieces. Then I changed the cutter to a round profile and went around the perimeter of the outer pieces, giving them a slightly rounded edge. Once that was done, I used a 2" hole saw to cut four 1/2" thick circles out of oak. These pieces were for mounting the idler wheels, and since the axles were 1/4-20 SS bolts, I wanted a dense wood to hold them. The disks were glued to both sides of the ram assembly and drilled with a 3/16" drill bit. This was then tapped to 1/4-20 using a handheld drill. I then did a test fit of the idlers - everything spun effortlessly!
The next step was the shaft of the ram, which I made out of 1" thin walled pvc. The 3" long sections were pressed into mdf disks made out of scrap I had lying around (remember the rings I made for the idlers themselves? Those were the insides) The assembly was then CA'ed to the flat end of the ram, and checked for alignment. Now I have to work on the other end that holds the other two idlers.

esavagenoobie

Looks awesome man! Very nice work.

Kitsune

My Feedback: (7)

Oh wow! This is going to be incredible!

rc awesome

This is going to be sweet! keep us posted

calvino

Wow you a machinist or something, that is amazing! Love how your using wood which isn't to common but still incredible [8D]

The_Shark

thats cool.

i would just glue a toaster onto a rc, stick binoculars on it and call it quits

ISIRC10

Well, I am not a machinist, but I do enjoy working with wood and being precise. I have been working with it since I was 5 when I built a small "garage" box for one of my dump trucks, so you could say I am familiar with how it cuts and sands.

On a side note, I checked the movie and saw that Wall-e's idlers only have 4 bolt holes. Oh well... not something I am going to lose sleep over. I also went to youtube and saw this
Damn... I wish I had those types of capabilities (moulding in particular)... but I must say, his drive isn't as scale as mine... guess I have something to work towards!

The biggest thing I envy on that walle is the tracks - how he just made a mold and poppped out all 66 track links with very little effort. My track is going to be less "scale looking", but also less expensive. I spent the first $7.00 on the project yesterday and it was for track materials. I will post later with details.

tommygun32

Can't wait...don't stop...

......wow...did you see the R2D2 Unit in the back....wow[X(]

rasper

i cant believe im saying this, but i actually just logged on to come and see the progress on this.......

ISIRC10

Today was spent cleaning the workshop, painting other projects (this requires nice weather), and cutting fiberboard - lots of it!
Nevertheless, I finished both idler assemblies and installed the wheels - I am beginning to like what I am seeing. all of the wheels roll smoothly, and although they have a bit of a wobble, it shouldn't matter as much once I am running tracks over them. On the topic of tracks/treads (whatever you want to call them)...

Wall-e has tracks made up of 33 links on each side. In the scale I am working with, that means 66 fiberboard strips 7 5/8" long, 1 1/8" wide, and 5/8" thick. I had some fiberboard sheets left over from something leaning at the back of my wood pile so I decided to use them. After changing the blade on my table saw (I didn't want to ruin my nice blade with the crap), I cut all of the strips in a half hour. Even though I had a dust collection system running, it took another 40 minutes just to clean up all of the dust from the process. The $7.00 Imentioned in my previous post was the 2" x 20' tie down strap I got at Harbor Freight. This plus the fiberboard strips plus the pneumatic nailgun and brads will equal treads... somehow. Now I know many of you might be thinking "but that won't be scale!" Well, since I do not have the luxury of molding track links or having them cut on a CNC mill/waterjet/lasercutter, I will use my own economical solution and save myself a good bit of time. I think the tradeoff between scale and resource allocation is a favorable one. Now let's hope my solution works!

Just a warning for those who want to work with particleboard - apparently it grows branches! So be careful not to let any of the sawdust land in your yard, or you might end up with a grove of particletrees. Consider yourself warned!

Looking at the pictures, I realised I forgot all about the drivetrain... oh well, I trust that you guys can figure out what that last picture is.

electricrc68

wow that is amazing!!!! keep going!!!!