A couple of people have asked about the replacement 2.5″ wheels I got for my front foot setup back in May from California Caster.

The soft rubber wheels are made by Darnell-Rose, and product number/markings on them show “Darnell Corp X-6 2 1-2 Calf.”. Unfortunately, I can’t find my original receipt nor the wheel in Darnell’s catalog or California Caster’s website. If I find it I’ll try and remember to update this post, but I think if you call up and say X-6 2- 1-2, you be okay.

oh! and a point of clarification, I’m still using the original Proctor Glove / Arrow Hardware caster assembly

Left: Original Proctor Glove wheel – shaved down to 2.5″
Middle: New Darnell wheel
Right: Full Proctor Glove 3″ caster

Maker Faire is just a day away, and I’ve had a busy time getting ready. This is probably my favorite event of the year, and we will have a good showing, with 4 droids and 6 builders in attendance. Bonnie Burton from SW.com will also be there running a kids workshop on Star Wars Puppet Craft.

Over the long Memorial Day weekend I stripped Artoo down for some long needed repairs and upgrades I’d been putting off.

I’ve replaced the center foot with the a new one from JAG with the taller skirt. Here’s a comparison shot with the new foot on the right

Sadly, with extra tapper of the foot skirt, the “Special” 3 inch Ace casters are too big and had to be re-worked. To be honest, they were a bit of a squeeze in the old foot, so I was on the hunt for some nice 2.5″ casters! I searched and searched locally, but couldn’t find anything suitable, I had three options, order something online, hack what I had, or just install one caster.

Long story short, I tried the last option, and even went as far as creating a new mounting bracket for one 3″ caster, but when I was done I then had to redo my ankle locks as there was now a backward tipping as well as the forward tipping. Hard to explain, but bottom inline I needed to redo my locks, which meant drilling more holes in the ankle that I wasn’t prepared to do….. back to the drawing board.

Because of time, and on Gerard’s suggestion, I resorted to trimming down the 3″ casters I already had. I mounted them in my drill press and filled them down.  It took forever, there was rubber dust everywhere, and it’s not something I want to do again.

What I’ve also realized is that never trust a label, the original casters were labeled 3 inches, but they were closer to 2 7/8th. Here’s a before and after comparison

After some finegaling, and making a new mounting plate,  I got them installed in the new foot – nice and level, unlike when I had the 3″ wheels.

Getting the right caster for the center foot can be tricky, it’s a balancing acts. You want the biggest wheel you can get fit, but because space is tight, the deeper you recess them to get things level the less space you have for a bigger wheel.

oh! and just as I was done with trimming the wheels, I went back and looked at one of the online stores I’d found earlier in the weekend, and what do I find – they’re LOCAL, or almost. They’re called California Caster and based in San Francisco, and had 100’s if not 1000’s of caster products in stock. I just had to make a trip up there. This was just a small selection of casters they had on display

Even though my new center foot was running again, I picked up these replacement 2.5″ wheel for the next round of maintenance.

I also replaced the radar eye with one I picked up from Dave Shaw many moons ago, luckily the old hole placement didn’t screw anything up. It doesn’t look too much different, and the wife thinks I’m crazy for swapping it out. I had the hardest time matching the Kryder blue, and it’s way to clean, but none of my panels match anyway 🙂

I can’t remember exactly what else I worked on, this was my droid on Sunday morning, all stripped down.

There’s been a long list of things I wanted to re-work, like shortening and re-routing some wires that were bugging me, to tweaking the front vents. I almost added servos to the utility arms, but that would require me filling them down and repaint – which I didn’t have time for.

But I did hinge manage to hing some doors in the body. I made some little aluminum brackets to help mount the servos to the frame

I know I worked on more stuff for Makers, but I can’t remember exactly what 🙂

oh! I remember, I’ve also been working on a small wireless controller based on a iPAQ Mobile phone, but more on that later.

Related:

• Proctor Glove Wheel Casters
• New Larger Casters and Angles
• Caster Fix and Test
• New Wheel Casters
• Fitting Casters for R2’s Center Foot

Nearly ever droid builder I know lugs around a large cart just in case their droid fails. This is especially needed for those of us with drive systems that lock when no powered is applied to the motors. Knock on wood, I’ve never needed to use my cart and it’s always stayed in the van.

Well, at WonderCon last week Gerard showed us his latest find – mini 6″ tri-wheel dollies that’s can easily be place under each drive wheel. They’re small and light enough to throw in your backpack or toolbox.

Only downside is the wheels are pretty small so wouldn’t go over any major bumps or door jams easily, and I wouldn’t recommend using them to totally replace your cart, especially if you use it all the time. Never the less, I went straight out and bought a set to have in case of an emergency.

Here’s Gerard in action pushing his droid around on two of these

[Direct link to Youtube video]

Manufacturer: Sheperd Hardware
Mode Number: 9299
Approx Price: $9

Available at Home Depot, Ace Hardware, etc. Cheapest online location: Ace Hardware Outlet ($5 ea.)

Short video shot by one of the staffers at Revision3

Notice the squeak? That’s one of my casters that needed some grease. It’s all fixed now, but it’s a good example of why you need to keep on top of regular checkups and maintenance.

I’ve received several emails recently on where I got my 3″ wheel casters from. These are the exact one’s used by Mike Senna and Victor Franco, so I can’t take credit for finding them – but the question keeps coming up , so I thought it might be a good idea to post the information I have.

I have no idea why these seem to work better than others, I think it’s a combination of the dimensions and having a soft rubber wheel that works on variety of surfaces – and the price is right too.

My first set came from a friend in Southern California who bought them at the Arrow/Ace Hardware in Yorba Linda (714-524-1621) for $7 each. Once I had them in hand I was also able to get my local Ace Hardware to order me some spares.

Here’s a close up of the label that might help –

Manufacturer: Proctor Glove
Part Number: 3RS
Description: 3″ Rubber Swivel 125lb
UPC: 7 80272 000003 7

They’re made in Korean and sold by Proctor Glove Co. who are located in Santa Fe Springs CA, or more specifically:

11122 Shoemaker Ave
Santa Fe Springs, CA 90670
(562) 903-1320

I don’t think any builder has called them up directly to try and order, but if you are successful please let me know and I can add it to this post.

A builder contacted them a few years ago and did a run of these, including offering the rubber wheels in softer or harder variants.

Related:

• New Larger Casters and Angles
• Caster Fix and Test
• New Wheel Casters
• Fitting Casters for R2’s Center Foot

I had to add some wedges/stops to the side of the ankle to stop the foot from tipping when going in reverse. As usual rather than reinventing the wheel I copied Victor.

I made a quick paper template that I traced directly from the ankle/foot. I then cut them from some scrap 1/8″ aluminum I had sitting around.

And finished them of with a clean coat of white (including the screw heads)

I tapped the side of the ankle, and also included a wooden block inside (also drilled/tapped) just in case the ankle wall thickness wasn’t enough to hold the screw.

Well, I’ve fixed the caster problem after a bit of detective work.

A few of you wrote to ask if the 3″ casters were touching the side of the foot shell, they weren’t but clearance is tight.

To simplify troubleshooting I took the center ankle/foot assemble off Artoo and was able to duplicate the locking wheel on the workbench. It even did it with the foot shell removed.

Turns out it was as simple as some crud in the casters bearing. They’d been siting in my workshop for quite some time, so who knows what had gotten in there. And no matter how careful I was, there’s a good chance I got something in there while I was trimming the caster base plate.

The symptom was when the caster did a quick turn it would freeze and drag, slow turns were fine – but anything rapid would cause the lock.

I got some degreaser and soaked the bearing. I then blasted it with air to try and knock out whatever was causing the problem. Once I was happy the bearing was turning fine I re-applied some bearing grease using a small syringe.

And here’s a short video demonstrating the new casters in action

Only time will tell if the new wheel casters perform better in the field compared to the ominballs.

I made a bit of progress tonight getting the center foot ball casters replaced with regular wheel casters.

One of the issues with using wheel casters is finding one’s that will fit. Many builders opt to use smaller 2″ or sometimes 2.5″ casters, but I really wanted to maximize the size to help with difficult terrain. I was lucky to get some of the magical 3″ casters from the Ace Hardware store down in So Cal with the help of a friend.

At first I thought they weren’t going to fit, so I double checked with Victor to confirm that he and Mike really are using 3 inchers. He assured me that they were and sent me some current photos to prove it, along with a few suggestions and tweaks they used to get them to work.

My plan is that any mods I make will not interfere with me going back and installing the original ball casters – just in case the new one’s do not work. e.g. I’ll be using the same mounting plate but will drill some new mounting holes.

I knew I had to remove some of the lip on the front and back of the JAG center foot shell – which I did with the Dremel and a file.

I also had to remove some of the casters mounting plate to allow it to sit closer to the edge of the foot shell.

It wasn’t important to keep the mounting holes as I’d planned on drilling new one’s to match the original mounting plate used with the ball casters.

Here’s the first real test fitting before any holes were drilled

Like an idiot I forgot to take photos of the new casters bolted into place, but I did shoot this short video showing them in action

As I show in the video, ground clearance is now 1.5″ as opposed to the 1″ I had with the ball casters. But this maybe a good thing as I plan on adding an extra “skirt” at the bottom of the foot shell to mimic the center foot as seen some of the movies.

It was getting late, but I did get the foot mounted and a quick test run highlighted a problem with the rear caster not spinning fully. I’m really not sure why it’s not keeping up with the front. It spins freely when I move it by hand but when I run the droid it seems to stick to one side and drag. If I spin him enough it’ll rights itself and sometimes it does keep up.

Here’s quick shot of it sticking – I was trying to do a right turn when this happened.

I suspect it might be something to do with the fixed angle in the outer feet/legs, using wedges, which should be an easy test to see if it’s the problem.

I also need to add some wedges to the front foot to stop it tipping. With the three original ball casters located in the extreme corners of the foot this rarely happened – but now with the casters closer to the center it tips/drags very easily.