Quick Index

Clodzilla Buildup
Gearboxes
Bearings
Custom Fabrications and Modifications
Axle Installation
Servos
ESCs
In Retrospect
My Setup
Misc Info

Pictures

Front
Rear
Left
Another Left
Right
Ladder frame showing wiring closeup
Chassis

More picture links in text below.

Clodzilla buildup

Tamiya 58065 Clodbuster kit
ESP Hobbies Clodzilla IV Pro Race Kit, ESP048

This project started 1/9/99. I finally finished it on 7/18/99. It had been in rough running form (w/o body) for some time, but now at least all the major pieces are there and I can leave it alone. I'm sure there are things I can tinker with, but I'm satisfied for now.

The Parma Gravedigger body is temporary until I finish painting my other body. I got it used, and almost got rid of it. It was originally on a Bruiser, which is why it had some extra holes in it.

Begin

** Get yourself a bottle of Loctite (242 - blue) or a bag of 3mm locknuts! **

The instructions assume you're starting from a full Clodbuster kit (or new gearboxes) and a full Clodzilla IV kit. Depending on how you started off you may still benefit from these notes, as the ESP instructions are pretty horrible. However, there is a reason why assembly takes place in a certain order.

1. Build the Clodzilla 4 chassis (esp045). Some minor pains are: some screws you have to get from other ESP packages (explained in instructions) but can be a pain. ESP screwed up by shorting me one 3x10 screw, instead packing a 3x5!

I really wish ESP had written the instructions using normal fonts and mixed case characters. It is a bit hard to read.

• It isn’t clear what you’re supposed to attach the battery mounts to chassis brace with. Not yet… (if you want to know, go to step 3)

2. I guess I jump to step #2 on the ESP instruction sheet, building the LWB multilink suspension kit (ESP032)

• Poor tapping job on some of the rods mean I had a hard time screwing in the studs.
• Save yourself some headache now by assembling the links with exactly the same length from rod end to rod end. My suspension links have a length of 165mm between eyelets, which is about 175mm end to end. This is VERY important if you want your truck to track straight. Note that 4 of the rods have rod ends at 90 degrees relative to the other end; they are the lower links.
• I worry about the strength of the shock mounts. They are stamped aluminum piece, and the bends in them show stress marks. We all know aluminum can fail with bending stress. We’ll see. ESP does have lifetime warranty on any part that bends or breaks, however.
• If you have RCCA May '98 issue, you might want to keep it handy for picture reference. It helped during assembly, when you're not sure how the complete chassis is supposed to look.
• You'll also notice that the RCCA truck has nifty 'skeletonized' cantilever cams (which the article pointed out), while the kit comes with plain triangle pieces. It is disappointing, after you shell out $220-240 ($300 SRP) for the chassis kit, that you get those plain-looking cams. The RCCA truck looks hi-tech. The ESP kit looks homemade. One guy I know actually got ESP to send them for free, but don't expect that to happen (they will 'customize' them for you for $$). I asked Eric at ESP for them, but no luck in getting them. Everyone should call or write ESP Hobby and complain! ESP Hobby website

3. Jump to ESP047 anti-sway bar kit, so I can mount those battery stays.

• It could’ve been more clear on the instructions. For example, the swaybar mount L-sections, the bottom of the L is on the bottom when mounted on the chassis brace.
• I substituted with Tamiya’s 3mm locknuts where appropriate (8 required).

So, you’d first build the suspension rods, then build the anti-sway bar assembly. The battery stays are secured with the same 3x15mm bolts for the lower suspension links (where I used 3mm locknuts). Picture1 Picture2

Then, the anti-sway chassis mounts are mounted to the chassis brace, using the same 3x15mm bolts for the upper suspension links (again, I used 3mm locknuts). Finally, the upper chassis and lower chassis are mated together. I substituted the kit 3x10mm bolts with Tamiya 3x10mm bolt, 3mm washer, and 3mm flange nut. (qty 4 of each used). Picture

Total time spent up to now: 2 hours, 20 minutes.

Gearboxes:

1/9/99Start 6:15PM, end 9:30pm

Start 12:45am end 3:30am

Parts B7 and B11 are not required, otherwise assemble as per Tamiya instructions.

Motor: pinion to motor mounting face: 17mm

Screw bag D discarded all 20 1260 plastic bearings.

Bearings:

Axles: 4 kit-supplied 1260 tamiya bearings, 4 optional 1260 bearings. Total = 8.

Gearboxes: 4 850 and 4 1260 optional bearings. Total=8.

Knuckles (hub): 2 1260 optional bearings per knuckle. Total = 8.

Size in mm, eg 850 = 8mm o.d. x 5mm i.d.

Step 26. You can temporarily skip this step until you get to ESP Dual Steering Kit. For ESP Dual Steering, you don’t need to install the 3mm nut inside each gearbox, and B11. Don’t bother installing the motor and B7.

Do not install Tamiya brass ball connectors on steering knuckles and servo saver/bellcranks.

Now is a good time to assemble ESP Deluxe Steering Rod Kit ESP037, and Dual Servo Conversion Kit ESP040. Tamiya's instructions tell you the INSIDE distance from rod end to rod end, while ESP tells you nothing. Best way is to assemble Tamiya's, then measure the eyelet to eyelet distance and replicate on ESP's. Here are my measurements:

Tie rod (short): 75mm eyelet to eyelet
Tie rod (long): 148mm eyelet to eyelet
(add 10mm for end to end length)

I modified the ESP servo mounts instead of modifying the gearboxes. See below.

When attaching Tamiya axle braces, instead of using kit 3x6 screw, use 3x20mm screw. You’ll use this to attach the upper suspension link. See my notes on axles.

Custom Fabrications and Modifications

I was not particularly satisfied with the engineering (or lack thereof) of certain aspects of ESP's kit. In particular, the radio tray and battery tray.

I feel that the radio tray puts the center of gravity too high. There is also no elegant way of securing the battery to the chassis.

• Fabricated a recessed radio tray to lower the CG to test out my concept.
  
• Cut off the excess metal on the L-shaped shock mounts from Suspension Kit ESP032
• Drilled an additional hole in each of the ESP Servo mount L-bracket, instead of cutting tab off gearbox, and cleaning up the stampings.

My recessed radio tray is made from sheet aluminum purchased at Home Depot. They are called "aluminum flashing" and you can find it in the aluminum siding section. It is fairly thin and easy to work with for prototyping.

• Radio tray - final version was done end of June. It was more complex than necessary. See "Retrospect" section for my thoughts.
• Adjustable aluminum front/rear body mounts, and aluminum antenna holder. The body mounts on 4 points, so that prevents the single main bodymount (on each end) from twisting loose.

The mounts can be adjusted to fit many Tamiya pre-drilled bodies. I had some predrilled bodies around, and I did not want to drill additional holes, hence my own design. Consideration was given for crashability. I do not want to bend the ESP ladder frame, so the chassis was braced. Note that the front brace has clearance to clear servo pushrod. The mounting posts can be replaced easily if bent, or if different heights are required for different bodies.

• Battery tray

It was made from a pre-bent plexiglass piece I found at a plastic shop. It was almost perfectly sized for a standard stick battery. The only thing I really need to do is to hold down the other end of the battery with a rubber band. Next step is to duplicate this design in aluminum, as plexiglass is too fragile (it broke already).

Notice the Trinity 3000mAh battery? On my Tekin BC112C, it takes 45 minutes to charge at 4A (no PF mode, no trickle), and the runtime is awesome. Note on 3000 mAh batteries: they get warm when they peak. You want to stop charging when the voltage stops rising so keep your eyes on the voltmeter during the last few minutes, and feel the pack (warm ok; don't let get hot). Do not let the voltage drop (over .02) because you might damage the pack.

Unscientific timing (hiking trail, 2x Trinity SpeedGem2 Sapphires, 1 outing)

3000 mAh: 15 minutes
2000 mAh: 11 minutes
1700 mAh: 7 minutes

Installing axles to the chassis

I don't think ESP gives you good instructions on axle installation. I've had to install and de-install my axles occasionally, and have come up with the following procedure:

1. Drill holes on axle tube ends (for mounting upper suspension link) as per ESP instructions.
2. Mount ESP shock mounts to Tamiya axle braces with 2 3x10mm screws, washers and flange nuts. Note: use the two outer holes closer to the wheel on the longer axle brace.
3. Drill out the wheel-side hole on the axle braces. You won't need the threads with my method.
4. Attach ESP lower suspension links to the bottom hole on axle tube end. Use a 3x15mm screw and 3mm washer, insert thru hole on axle tube from outside in, then install the conical washer, rod end, followed by loctite and 3mm nut.
5. Attach ESP upper suspension links to the top hole on axle tube end. Use a 3x20mm screw and 3mm washer, insert thru hole on axle tube from outside in, then thru hole on axle brace (the previously prepped hole), followed by conical washer, rod end and 3mm washer. Now, instead of using a nut, we'll use the swaybar's rod end to hold things in place. Slip the swaybar onto the rod end first, then screw in the 3x20mm screw tightly into the rod end.
6. Mount your steering knuckles and tie rod assembly. Lightly grease both sides of the 4mm washers. A little bit of grease helps keep them on the knuckles. Lightly grease the kingpin bolts too.
7. If you wish, attach Tamiya kit bumpers to the gearboxes. You will have to make a small trim on the mounting end that attaches to the short axle brace. I used 3x8mm screws on the top, and 3x12mm on the bottom.
8. Attach ESP cantilever pushrods.

Picture of attached axle

1/12/99 start 11:30pm end 1:30am

Cantilever suspension system. It would’ve been nice if ESP included the allen wrench necessary for the cantilever bolts. It is SAE size and I had to scramble around for one.

Notes on Servos

The goal was to have dual steering as intended by the kit. Clodzilla 4 dual steering requires 2 servos connected via a y-cable. Naturally, if you use matching servos, you either have to mount one (rear servo) upside down, or find a way to electronically reverse the servo (NOT from the TX). The solution suggested by ESP is to mount the rear servo upside down. Since the rear servo uses a smaller servo saver, it can work work. In actuality, the servo saver will most probably hit the motor can (trim the servo saver to fit), and the servo rod is a bit on the short side.

I’ve gone through several different makes and models of servos.

Futaba S9402
Futaba S148
Airtronics 94102
Hitec HS303
Futaba S3003
Hitec HS605BB

I originally wanted two different servos, that rotate opposite from each other. This way, the servos can be mounted the same way. S9402, S148, HS303, S3003 all rotate the same direction. HS605BB and Airtronics 94102 rotate the opposite way. Note my 94102 is very old (15 years old?) so I can’t guarantee they are still the same these days.

There are workarounds if you want a clean installation using two identical servos. Tower sells an electronic servo reverser (look in their main catalog), or dissect the servo and reverse some wires. Do NOT just pull out the control wires (+ and -) and reversing them. You will most likely fry your servo.

In theory, you can reverse a servo by opening up the case and doing the following: desolder the motor +/- tabs from the PC board, reverse the motor (rotate 180 degrees) and solder back. Then desolder the outside two wires for the pot, cross them and solder back. This was told by various members of the R/C community, and from a Hitec technician himself (of course, this voids the warranty).

Eventually, I used Hitec HS605BB high torque servos and reversed one of them. Here's how:

1. Open up the servo by removing the 4 screws on the bottom.
   
2. Lift off the bottom cover.
   
3. You'll see the motor and a PC board. Make a note of the original wiring arrangement.
   
4. Unsolder the two wires on the motor, leave them alone for now.
   
5. Carefully lift off the PC board. You will see the pot (potentiometer) below with 3 wires soldered to it. Make a note of the
6. original wiring arrangement.
   
7. Unsolder the two outermost wires on the pot, reverse them, and solder them back.
   
8. Reverse the two wires to the motor, and solder them back.
   
9. Carefully replace the PC board, and reattach the bottom cover.
   
10. Test the servo. Rotation should reversed compared to the original.
    

For this particular servo, it is a 10-minute job because the motor and pot are actually connected with wires, and not soldered onto the PC board like some other servos encountered. YMMV.

Mount your servos to the ESP servo mount with double-sided servo mounting tape, and zip tie them down securely.

ESCs

Most higher-end ESCs can handle single servo/dual motor setups fine, I've found that you MIGHT run into power problems running two servos and two motors. I've used LRP’s F1 Bullet and F1 Digital, and Novak's Super Rooster on my chassis. Try this test: Crank the steering to full lock, and hold it there while applying throttle. See if the truck goes forward immediately. LRP ESCs won't respond until you let up on the steering, while the Super Rooster worked fine. This is regardless of the make/model of servos or motors used.

I suspect this has something to do with the ESC's BEC output. LRP provides 0.5A while the Super Rooster provides 3A. So, if you encounter the same problem, try the Super Rooster.

I did notice that the Super Rooster runs a little warmer than the LRP F1 Bullet, but it isn't a big deal. The LRP works beautifully in touring cars, BTW.

In Retrospect

• Get a large bag of 3mm locknuts. Or have a small bottle of LocTite handy.
• Make sure you have plenty of room to lay out everything. This won't be a quick buildup.
• Instead of making a recessed radio tray, you can probably narrow the existing aluminum panel and mount it on the bottom of the frame rails.

My Setup

• Clodzilla IV Pro Race Kit (ESP048)
• Clodbuster gearboxes, full ball bearings
• Trinity SpeedGem2 Sapphires, which replaced my Trinity X-Star normal and reverse rotation motors. There is a noticeable improvement.
• HiTec 605BB servos (one modified for permanent reversed operation), Kimbrough servo savers.
• Hitec Shredder micro receiver.
• Novak Super Rooster ESC.
• Trinity NiMH 3000 battery.
• Bullhead chrome rims, yellow bumpers.
• ProLine Giant Traction tires.
• Kyosho Platinum 4" shocks (no longer made).
• Stock clod parallel/series motor wiring switch retained for now.
• Parma Gravedigger body.

Misc Info

The Clodzilla 4 Pro Race Kit box measures 12 ½" x 11 ¼" x 2 ½", and weighs 2.2 lbs.

The Clodbuster kit box measures 26 ½" x 18 x 6 ¾", and weighs around 12 ½ lbs.

What’s the difference between Tamiya 6mm Ball connectors and ESP’s? ESP uses ¼", or 6.35mm Balls. You can connect Tamiya ball connectors to ESP’s rod ends, but there will be some play.