JAG Center Foot Mod – Lip/Skirt

A couple of months ago I’d posted to the main astromech.net forum about modifying the JAG center foot to include a more pronounced skirt at the bottom. At first not everyone quite understood what I wanted to achieve.

Here’s some reference shot of the Uber R2 that may help

And here’s a screen cap from ANH with an even bigger skirt on the center foot

What set me down this path was seeing my droid next to Gerard’s (his is on the left). Note the difference in the center foot?

I think weathering helps define the foot as well, and to stops the white making the foot look more like a blank floating triangle/wedge.

This is Gerard’s raw Weaver foot

After a lot of debate most people finally got what I was trying to say, including JAG who may include the mod on the next run of feet. But I thought I’d see if I could modify my current foot in the meantime.

I created an little frame out of angled aluminum (1/16″, 1/2″x 3/4″), and the plan was to pop rivet it onto the existing 3/4″ lip around the foot.

IMG_0703

It wasn’t perfect and I knew I wouldn’t be able to get the corners angled correctly, but was hoping to blend in the frame using bond or something.

Here’s the foot with the temporary skirt. A little too tall I think and I’m not crazy about the corners being straight as opposed to angled, so I’ve decide to see if I can find someone to lend me a welding ring to make a more accurate skirt/frame.

IMG_0717

Posted by Chris on June 8th, 2008 in Feet, Legs | No Comments

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New Wheel Casters

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.

Posted by Chris on May 27th, 2008 in Feet, Legs | No Comments

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Leg/Ankle Screw Update

I wanted to report that the new method of attaching the JAG legs and ankles worked. I didn’t have any problem with screws working loose while at WonderCon, unlike at C4, where I had to constantly tighten them up – and had two screws sheer on me.

Back in December of last year I’d decided to use pan head screws with a combination of fender and lock washers , instead of the recommended countersunk machine screws.

They’re do stand out a little but, but once I’d painted them up nobody really noticed them.

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Posted by Chris on March 30th, 2008 in Legs | No Comments

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