MCK-Y the Lego Mouse Droid Build

[kresty]

Way awesome! Looks just like the computer design said it would.

The bean story is friggin' hilarious. What ever made you think of beans?

Thanks,

Our first thought was spray foam, but that was messy sounding and little time, so Lara suggested marbles, which was complicated because we figured toy stores might be closed. (I was also worried they'd be too big). We thought for a bit and beans were the thing that came to mind. Since then folks have suggested the foam beads, which might work, but beans are pretty accessible.

There was a bit of "bean dust" in the one wheel that leaked, but not much. We aren't sure how successful they'll be long term.

Since the original idea was foam and the beans (or the Lego tire studs, or our not-straight hubs) give him a funny gait Lara wanted to go ahead and try the spray foam, maybe swapping wheels for the second day.

I wasn't sure it was worth the effort, but Saturday night we filled 2 spare wheels/tires with spray foam. That was a disaster. Without air, the foam didn't set (duh), and it actually lost volume. They look really silly. The round one collapses on touch.

When I opened them they actually sucked in air (partial vacuum inside), and of course the inside was runny & stuff. I propped them open so hopefully they'll set and we'll be able to clean them enough to reuse them, but that experiment was a total flop. We might try again if we can figure out a reasonable way to ensure they have a chance of curing.

[lynellephi]

That's freakin' awesome! MCK-Y certainly has a great look to him.

I noticed that my droid was driving a little lopsided, so I made a battery mount out of bent metal and 3M picture hanging tape, mounted that crosswise (parallel to the back end), and mounted the battery on the metal shelf with cable ties. Now it doesn't wobble like before. Reason for the wobble was the battery was mounted on one long side of the chassis, making the center of gravity way off. If MCK-Y is wobbling try mounting the battery crosswise somewhere near center of the chassis. You might have a center of gravity problem. You also might have to get hard foam (or rubber) wheels instead of those plastic tires. Those tires probably can't handle the weight of your droid. I do like the look of the tires, but sometimes it's best just to accept defeat. I'm getting rid of R2-AL's pneumatic tires for hard rubber wheels even though I really tried to make the pneumatic ones work (I'm accepting defeat and upgrading AL).

[kresty]

Thanks, battery is very center. It's more likely hubs or beans, but I'll post more pix later.

[Ziz]

Can you fill the tires with foam, let it cure, then stick the hub in? Or does the hub have to be in for the tire to hold its shape?

[kresty]

Can you fill the tires with foam, let it cure, then stick the hub in? Or does the hub have to be in for the tire to hold its shape?

I was wondering about that, trick is how to keep the foam from filling where the hub goes. Hmm, maybe not worry about it and cut off the overflow after it cures? Might try that after I clean up some of these icky tires.

Another problem is each experiment seems to kill a can of foam

[Ziz]

Exactly - cut the foam off after it cures. A lot of model guys use foam to reinforce vacuform model kits and that's exactly what they do - fill the part expecting the foam to overflow a little then trim/sand after it's solid.

Also, guys have learned to work sparingly - put in a little foam, let it expand and cure, then come back and add more. Don't try to fill the whole thing on the first shot.

[kresty]

Also, guys have learned to work sparingly - put in a little foam, let it expand and cure, then come back and add more. Don't try to fill the whole thing on the first shot.

How do you save the @!($*&@$ can?

[Ziz]

Depends on what you buy and how it's designed to be used. Look for something that doesn't require you to empty the can all at once.

[kresty]

Depends on what you buy and how it's designed to be used.  Look for something that doesn't require you to empty the can all at once.

We've foamed some wheels, but are currently having hub problems.  (Wheels don't work if they won't stay on, duh!!!)

[Richard Davies]

To save the can from becoming unusable, I turn mine the wrong way up, and press the knob, until just the gas comes out.