Jump to content

Rat-rod Grasshopper

markbt73

By markbt73
in General discussions

 Share

Recommended Posts

markbt73 Newbie Copy

markbt73

Posted
Posted

I wish this could be a build thread, because I really want to try this. But I'm moving to a different city in a few weeks, and I won't have time to actually do it until I get settled. But the idea is so strong in my mind that I want to put it out there now.

I have a re-issue Grasshopper that I don't quite know what to do with. My wife bought it for me for Christmas last year, and I built it box-stock and ran it a couple of times, but I had forgotten how slow it is with the 380 motor. It runs forever on a battery, true, but the excitement just isn't there. And since I also have a Lunchbox, which doesn't get hung up on the terrain as easily, I tend to favor that as a basher, so the Grasshopper just sits there.

I remember reading somewhere a while back that the Grasshopper/Hornet was the Model T Ford of the RC car world, the one that put the cars in the hands of the masses. A simple, "good enough" design, reliable, easy to fix, often imitated, ubiquitous.

And what did people do with old Fords when newer, better cars came along? Hot-rod the almighty you-know-what out of them.

In this spirit, I have already installed bearings in the Grasshopper, a mix-and-match hodgepodge of bearings I had leftover from some other cars. For power, I have an old Trinity stock motor, and I think I have the right size bearings to install in the motor can, sort of the RC equivalent of getting a junkyard Chevy 350 and dropping a four-barrel intake and carb on it. I might go bigger with the power later, but I want to start simple.

Wheels and tires, usually the first thing everybody changes on a full-scale hot rod, will probably stay stock until they're worn out. I have an idea of how to make moon hubcaps from the bottom of aluminum cans. If it doesn't work, I'll paint the wheels red. If I can figure out how to do wide white walls, I might do that too.

Now, as for appearance... I think for starters, the stock body will get the "rat-rod" treatment, a simple coat of flat black primer. And maybe later I'll try my hand at pinstriping. I want it to still look like a Grasshopper, but a vintage hot-rod interpretation of a Grasshopper.

And like any good hot rod, it will never really be done. But I want to start with this stuff, when I have time. And I'll post pictures....

Saito Mentor

Saito

Posted
Posted

Sounds cool. I'm a big fan of nostalgia hot rods myself. I remember precisely which article mentioned the Grasshopper and Hornet as being the Model T and Model A of RC. It was a five year retrospective piece written in the early '90's by RC Car Action. I believe Chris Chianelli (SP?) wrote it as a sidebar to the main article.

markbt73 Newbie Copy

markbt73

Posted
  • Author
Posted

I got a start on the "Rat Hopper" tonight. I wanted to lower it, but how do you lower a car with a swing-arm front suspension without ending up with 30 degrees of negative camber?

As it turns out, quite easily. You just have to think like a hot rodder.

1. Disassemble the entire front end. Remove the front springs, bottom "shock ends," kingpins, those U-shaped metal brackets, everything.

2. Remove and re-install the front arms, swapping the left and right sides and installing the arms upside-down. In this orientation, instead of angling downward slightly, the front arms angle upward slightly.

3. Drill out the round plastic bosses on the bottoms of the front arms (which are now on top) and screw the U-brackets onto them. Reinstall the bottom "shock ends."

4. Cut two pieces of rubber tubing about 3/16" (5mm) long. Using 3x15mm machine screws in place of the stock spring shafts, and the tubing in place of the front springs, attach the shock ends to the front towers.

(Note that the suspension arms won't move, because the holes are slightly off. This means there is no front suspension except for tire bounce and slight flexing of the shock towers. This is okay because I don't plan to run the car off-road anymore, but I might work on re-engineering the front end a bit further to put some suspension movement back in. I'll have to drive the car and see how it handles first.)

5. Re-install the uprights and kingpins, with the ball end still on top. I had to shorten the tie rods about 1/8" (3mm) on each side to get rid of excessive toe-in.

On the rear, I simply replaced the shocks with threaded rods and tie rod ends, so there is no rear suspension either. Overall, the car sits about half an inch lower, and slightly lower in the front than the rear. I love the stance; it's exactly what I was going for.

I also took the gearbox apart and added rubber O-rings to the diff gears to create a limited-slip "posi" effect, as suggested by Davewins13 in this thread (thanks Dave). I have yet to see how well it works, but it feels about right. It also got a motor swap to a 540 and full bearings. The next step, which may be a while because of time constraints, will be flat-black paint for the body and bright red for the wheels, for the rat-rod look.

More and better photos of the front end modifications later, when my wife is around (she's a much better photographer than me, and has a better camera).

And I need an opinion - front bumper or no front bumper?

Mad Ax Newbie Copy

Mad Ax

Posted
Posted

Wicked! That low stance is awesome. I'm sure it'll be a riot on smooth tarmac.

I am perennially tempted by the Grasshopper re-re because there are so many upgrade possibilities if you're prepared to "think outside the box"*

Keep us updated.

*and maybe even "run with the ball", if you're really into management speak

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Recent Status Updates

×
×
  • Create New...