Speedy's "Bump Steer" Lunch Box Build Thread

[speedy_w_beans]

About a year and a half ago there was a thread about "modern classics." In it a few of us had some fun expressing ideas and proposals for new animal-themed RCs. The premise was certain models, such as the Grasshopper, Hornet, and Frog, had enduring popularity maybe due to the unique chassis, low cost, and animal themes. What would Tamiya create today if they continued in the same vein?

http://www.tamiyaclub.com/forum/index.php?showtopic=65443

Anyhow, I had posted some thoughts about a custom Lunch Box called "Bump Steer." To me it was meant to be a joke or a pun bringing together the handling characteristics of the Lunch Box (lots of fun bump steer and wild bouncing) along with an aggressive cattle-based theme. "Bump Steer." Get it? Hahahaha!

The idea sat dormant for awhile, but this past month I retrieved my last surviving Lunch Box shell from the garage and started thinking about the build. This thread is meant to show some progress and have some fun as it comes together.

The build started easily enough -- strip the bumpers, side steps, and windows off the shell. Give everything a thorough cleaning. Polish the windows to fix some scratches. Now what?

Originally I had a thought about painting the shell a dark brown and "branding" it with a black logo decal, but that wasn't sitting right with me. What I really wanted was (fake) cattle fur covering the shell to make it different. My wife and I went to the local fabric store to find something passable as fur; I don't think the lady behind the cutting table expected our answer when she asked what we were working on. "Have fun with your furry truck," she said as we left the store.

There's no such thing as a pattern for cutting out fur before attaching it to a Lunch Box. I basically decided there would be a seam down the middle of the shell; there would be a left half and a right half. As far as attaching the fur to the shell, I used contact cement and worked in small sections. There were certain places where I needed to stop gluing, make cuts in the fabric, and then continue gluing. Most of the work was around the front windshield and the rear doors. I stretched the fabric a little while applying it around windows and the bottom edges of the shell. I also tried my best to cut accurately and stretch the fabric to hide seams (except in the middle of the shell). When the glue completely dried I was able to trim the fur back to the plastic using a fresh Xacto knife. End result -- One brown furry Lunch Box shell waiting for more details.

When I first had the idea for this build, I was thinking about swapping the yellow Lunch Box wheels for chrome Midnight Pumpkin wheels and staying with chrome for everything else (bumpers, sidesteps, shocks, etc.). That seemed like too much. Think about cattle -- there's no chrome on them anywhere. So it seemed more appropriate to strip the chrome off the parts and paint them black. I'm still waffling a little on the shocks and wheels, but for the main shell I stripped the bumpers and sidesteps with bleach and painted them with some semi-gloss black. My thinking right now is brown for the main color, black for major accents and trim, and some silver or chrome for smaller details.

With the fur attached, the bumpers and steps painted, and the windshield installed, I thought this would be a good time to "brand" the fur with the Bump Steer logo. I found a free western-style stencil font called Maverick BE and printed the logo to a few sheets of paper. Then I cut out the black lettering using an Xacto knife and a sheet of Plexiglas, creating a reverse paint mask to tape onto the fur. With a few shots of black spray paint and some touch up with a Sharpie marker, the logo was in place.

I know, I know; that's a lot of typing and explanation without any pics. Here's where it stands at the moment:

I'm pulling together some more material for more features, including:

- Horns

- Red LED headlights

- Smoke unit and servo-actuated air pump to "snort"

- Nose ring

- Some leftover Parma sponsor decals

- Possibly some parts for the rear.

So that's where it stands for now. Comments and questions welcome!

[TA-Mark]

Oh wow! Great theme.

When I first seen the pictures though, I straight away thought of the 'doggy' van from the movie 'Dumb and Dumber'.

Texas number plates are almost a must! ...oh and the poor steer needs a tail.

[94eg!]

[neverfollow]

Very original! Great work!

[JeepnMike]

This has to be a first.. LOL I love the logo!! Lots of original ideas on this forum but this one sure is different! It is like a cross between the Dumb And Dumber van and "Monster Mutt" the monster truck.

[dyahipfakta]

That's mint! Love it

[markbt73]

Put a brushless motor in it, and that thing will moooove.

(sorry)

[Psylence]

"Have fun with your furry truck."

HAHAHAHA! I can imagine her expression. That's great, made my morning!

[lawdog]

Put a brushless motor in it, and that thing will moooove.

(sorry)

Just don't try to milk it...

[Theibault]

I'm a bit bullish on this build. Can't wait to see more.

[mr crispy]

I like it. Just needs Wild Wendy riding on the roof!

[GregM]

Your Bump Steer might

Just don't try to milk it...

...or this Bump Steer might become a quite Mad Bull.

I like the fur - no more sounds of scratching polystyrene when accidentally rolling this truck on tarmac. But keep a hair dryer ready if you run through puddles. Good job on the red front lights.

[Foxone]

cow bell swinging off the front bumper?

Or just some horns pointing out if you're gonna make it snort smoke....

even as it stands now it's great, well done!

[speedy_w_beans]

Thanks for the support, guys. More to come soon.

[RichieRich]

How about a nose ring on the grill and some horns on the roof?

[speedy_w_beans]

How about a nose ring on the grill and some horns on the roof?

That's part of the plan. See above.

[Grastens]

Yes! I do remember the Bump Steer well, but am so very excited to see it actually being built!

I have no doubt you will make an awesome project out of the idea. I will be watching this build thread very closely, and anticipate the results!

[speedy_w_beans]

One of the key features of this model will be how Bump Steer snorts and breathes. I finally had a block of time tonight to make some progress on the smoke unit...

Model trains, model tanks, etc. all make smoke by vaporizing lightweight oil with a heating element. I did some research and looked at available options, but decided to make my own smoke unit specifically for this car.

Nichrome wire (http://en.wikipedia.org/wiki/Nichrome) is used for heating elements in toasters and hair dryers; it's the same wire used in smoke units. I found an old hair dryer in one of our junk drawers and stripped it down for the wire...

With a little bit of trial and error, I found roughly the right length of wire to use with a regular stick pack battery...

The length of wire measured about 1.6 ohms cold.

The heating element required about 5 amps when hot. I was expecting it to draw more current when cold, but surprisingly the current stayed relatively constant from first connecting the battery to the moment it glowed orange.

[speedy_w_beans]

I clipped the wire from the hair dryer and uncoiled it. It's surprisingly stiff wire. The idea behind the smoke unit is to have a small reservoir of oil, a wick to draw the oil up, and then the heating element to vaporize it. I had ordered some fiberglass gasket rope used in wood burning stoves from my local patio and hearth store; this will be my fire-resistant wick...

Nichrome wire wound around the fiberglass rope...

I test fired this to make sure the rope really wouldn't burn. It released just a little smoke initially but then didn't do anything else.

I put a half dozen drops of model train smoke oil in the middle of the wick and tried it out. The picture doesn't do it justice; I had a lot of smoke coming from just a few drops of oil, and the whole first floor of the house really started to stink. It was a pretty decent pillar of smoke going all the way to the ceiling. The smell reminded me of birthday cake candles (x1000)!

[speedy_w_beans]

Time to connect some non-nichrome wires so it can be installed in a box and powered remotely. It's not possible to solder the connections because the wire gets too hot; I used some very small brass tubing to make some crimp rings.

Crimps complete...

Time to drill some holes in a small plastic box for the heater wires, an air inlet, and a pair of air outlets.

Top side of the finished cover...

[speedy_w_beans]

Bottom side of the finished cover...

Finished assembly...

The heating element is almost perfectly centered between the floor of the box and the bottom of the cover. I trimmed the wicks back just a little and then curled them over to make contact with the floor of the box so they would draw up some oil. I need to put a strain relief on the wiring outside the box so the heating element doesn't move up or down inside the box; I'll do that tomorrow. Once I have the wires secured, I'll fill the box with a few millimeters of oil and then run it outside for a half hour to make sure it doesn't melt down.

Side note: I've been thinking about the color scheme some more. I'm pretty sure at this point I will go for the chrome shocks, wheels, and nose ring. The silver screws are bothering me. I'm thinking about painting the screw heads black and stripping the chrome body mounts so those parts won't be so distracting.

[mr crispy]

Nice smoke unit. I never thought to use an old hair dryer for parts, I even have a couple broken down in my "useful parts" box. Are you going to run a fan with it to get the snorting effect? I'd love to see a video of it running speedy

[speedy_w_beans]

A little bit of progress to report...

Last night I built a fresh Lunch Box chassis. It's pretty much a box stock build with only a few exceptions.

First, I eliminated the wimpy springs that are supposed to support the rear axle rod. In their places I simply installed some lengths of leftover sprue to fix the rod in one position. This makes the Lunch Box corner flatter and reduces a weak point in the design. The downside is the right and left sides are locked in position which makes the axle behave like an anti-roll bar. The Lunch Box definitely corners flatter, and there are no small springs to break, but the downside is that the rear suspension is a little stiffer when landing jumps off kilter. It's very much like taking a Hornet suspension and converting it to a Grasshopper suspension with the fixed swivel points. I've built another Lunch Box with this suspension setup in the past and liked it, so I know what to expect on this one too.

Second, I added a few millimeters of rubber tubing underneath each shock screw head. This does a few things. The suspension is quieter because the screw heads don't clack against the plastic chassis directly. Also, the ride height is just a little lower; this reduces the extreme camber due to droop quite a bit.

Finally, I changed the yellow wheels for some Midnight Pumpkin chrome wheels. I definitely like these more than yellow, or even painting the yellow wheels silver.

EDIT: Also added a full set of bearings...

Tonight I installed a nose ring and some nostrils in the front grill of the body. The nose ring is just a key ring I found at the local hardware store; I like the chrome thumb screw. The nostrils are 3/16 inch styrene tubes cut to length and glued in place. I need to sand down the grill a little bit and apply another coat of paint to make the front end completely black again.

Here's a quick test fit of the body on the chassis... I'm still stripping the body mounts in preparation for paint as well. Once the body mounts are ready, I'll paint them as well as the body screws and front grill. I left the big front bumper off; I'm not sure if I'll leave it off to show the nose ring more prominently, or put it on to protect the front of the model better...

[Theibault]

Looking good!

[JeepnMike]

I like the touch from the wheels, it definitely adds to the look. Very unique and cool!