Clod Buster 'Instigator' Chassis Build

[Wystan Withers]

Finally finished my Clod chassis design, so here's a quasi step-by-step build as I polish up the instruction manual. Amazing how time consuming writing that has has been.

Why does the world need a new Clod chassis when the JConcepts Regulator has pretty much perfected the Retro Racing Clod chassis format? One word: frugality. The Regulator's great by all accounts, but it's pricey. It requires that you upgrade to servo-on-axle steering and shorty lipo batteries with corresponding lipo friendly electronics from the get go- that's one heck of a barrier to entry for an initial upgrade from the stock Clod kit. My Instigator chassis is designed to be both a race-capable chassis taking advantage of the lower center of gravity achievable with SOA and shorty lipos, but also as a direct replacement for the stock Clod plastic tub requiring no other changes and is intended to be a guy or gal's first step in upgrading their Clod which can grow with them as time goes by. It is designed to use the commonly available aluminum Clod chassis braces on everyone's favorite auction site as another cost saving measure as I assume most folks acquire one of those as their first upgrade for the plastic tub chassis and thus by re-using a part they most likely already possess even greater cost savings can be achieved. And or by purchasing it directly themselves, they aren't having to cover the CA sales tax I have to pay.

So with all that said, lets build!

 

 

So here's the basic kit- some CNC cut G-10 bits and lots and lots of hardware. One nice thing about my system is that one need not buy things twice- want red CF sides and gold stand offs? No problem. If I can find it in 2mm sheets, I'll cut it. No more paying for an expensive kit, then paying for expensive accessory colored CF bits only to discard all that CF you just paid for in the kit. Each chassis can be custom ordered  to your color preferences from the beginning.

 

 

 

 

[Wystan Withers]

The first step is the assembly of the battery/electronics saddle. This saddle will accept standard stick packs as well as long or shorty lipos. A dedicated shorty lipo saddle is available, or the standard saddle may be trimmed by the user. The saddle may be installed in one of three positions- the uppermost position is used when retaining the stock center servo, the center postition may be used when using long batteries and Servo-on-Axle steering, and the lowermost position may be use when using SOA steering and shorty lipos for maximal lowering of the center of gravity. The 'long' plates must be trimmed before mounting them in the lowermost position. The center position lowers the battery 14mm, the lowermost position 28mm.

 

I'll be using a stick pack for this build, so the included foam battery bumpers will be used.

 

26mm M3 stand offs are used in between the two plates, and there are three positions to compensate for variances in battery length.

 

 

Here's the assembled saddles, standard and short.

[Wystan Withers]

The next step is primary chassis assembly. A total of ten 80mm M3 standoffs are used between the chassis halves, their standard sizing allows user to change colors on a whim, or to replace them with brass as needed for chassis tuning. Assembly is done upside down on a flat surface to ensure it stays true.

(Note: this is my personal chassis and as such has been assembled and disassembled several times, so I'll ask your indulgence if there are Loctite halos or surface damage visible here and there)

 

 

Next comes more stand offs and the damper/body mount blocks. These afford two different types of body mounts, either stock Clod or JConcepts lexan body mounts #0484. To use the lexan body mounts simply remove the silicon tubing reducers from the bocks and install the included M2.5xM4 threaded pins from the inside of the chassis. Body posts can be adjusted to your desired height as needed.

Note the use of the short saddle in the lowermost mounting position.

 

Standard configuration, standard saddle in uppermost position.

If using the Clod Body and body posts, the body post pates are used, attaching the mounts first to the plates themselves using an M3x8 countersunk screw in the outermost hole, then attaching to the damper mount blocks using M3x20 flanged head screws up from the bottom. Optionally one may attach an antenna tube holder such as Tamiya 13455055 or aftermarket equivalent. Sliding the mount all the way to the end of the slot will align it with the hole in the Clod body. I have a front bumper mount for the Clod body available for shelf duty, but it is rather fragile and not recommend for runners.

 

 

[Wystan Withers]

Next we assemble the lower chassis saddle. These are the common unit available on eBay and I assume the CPE unit will also work, however the CPE unit does not have the servo mount holes pre-drilled. You'll need to drill these holes if you wish to use the center servo mount, or wish to add the custom chassis weights later. Did I mention that you can also add 'tunable' weights to bottom of the chassis in order to help make weight for certain racing classes? Yeah, that's a thing

So we're going to start by adding the chassis saddle to the included brass lower chassis plate, placing the plate inside the saddle and screwing the 4mm suspension balls from your Clod kit into the plate (the holes are tapped and threaded) Then we add the flanged lock nuts for extra added security.

 

Now mind you, if you're a nerd like me you'll want to retain the center steering servo even if just for the pure nostalgia of it and to do so simply install the original servo mount from the Clod kit (part A5) and install using the M3x8 screws. But, if you're a 'special' kind of nerd (like me) you may optionally install the accessory brass servo plate designed to accept the JConcepts brass servo mount for the Team Associated DR10 #2877. You may also use the commonly available "SCX10" alloy servo mounts, the offset is the same.

[Wystan Withers]

Lastly we attach the lower chassis saddle to the chassis using the 8mm suspension balls from your Clod kit and the threaded metal backing plate, though of course you may choose to replace the plate with M4 nuts.

 

And here we have it, all assembled and ready to accept your axles and electronics, exactly as you would install them per the stock plastic tub. Relative to the stock tub (measured at the stock damper mounting height and the upper damper holes here), the stock Clod body mounts about 3mm lower, the lower plate is raised 7mm and allows for a full 25mm of bind-free suspension travel, although the stock 'dampers' will only allow 19mm of travel with the limiting tubes removed. The row of lower holes for the damper mounts is set at 10mm lower so as to achieve a stock ride height if using 90mm dampers.

Why G-10 and not carbon fiber? It's half the price and still maintains enough of a stock look that at a glance doesn't scream 'hot rod'. Frugality. 

(yeah yeah, this pic is the final 3d printed prototype chassis, but my last rattle can of black paint died and I haven't replaced it yet for final reassembly)

 

[Saito2]

I like it. It addresses all the problems I had with the Regulator chassis. Well done!

[MetalMilitia]

Great looking chassis Wystan!

[Mouc-RC]

Love that you keep the chassis-mounted servo. It really preserves the iconic look of the Clod me thinks.
If they ever re-release the BullHead once again, I may try to get a fancy black chassis like yours for it

 

[MadAnt]

Pretty cool! What is the goal sale price?

[Wystan Withers]

First one is on ebay at $150, the chassis braces (if one does not already have one) seem to hover at $35.  That might come down a bit in the future as I streamline the process, but if I had to guess there's 10-12 hours 'labor' in each kit (admittedly most of that is babysitting as the CNC does it's thing but it still requires a clear schedule to keep an eye on it), and I don't want to even hazard a guess as to how much design time is in it. For the time being my model is "sell one, make two" rather than spend a ton of money up front and making a dozen of them and get stuck with a bunch of inventory. This has been a 7 month project, I destroyed more than a few sheets of G-10 getting here, not to mention a very steep learning curve cutting brass (ashamed of how much of that got wasted at $8 per pound)... my break even point is a very distant dot on the horizon. That said, the hardware is all normal stuff, so a 'minimalist' kit is also a possibility if you already have a stack of M3 assortments on your hobby shelf. Not trying to put 3 kids through college, but I do dream of getting my hobbies to support my hobbies

Key for me with the design was compatibility with stuff guys may have already spent money on, like lexan bodies, whichever size batteries they might be invested in (lipos aren't for everyone) etc. I can't be certain, but I'm 99% certain the body post locations are the same as a Regulator, length is likely a lock, the width might vary by a mm or two so reusing old bodies should be possible. The dimensions of the outer faces of the chassis plates should be the same, I'm just not certain about the exact measurements of their damper spacer/body mounting block. Unfortunately JC doesn't sell the blocks separately (I tried) as I would have preferred their aluminum units over my 3d printed units. I'm using a nylon-like resin so they should be strong but not brittle, but I'm making those public domain so if people want to print replacements they can, or I'll warranty them if need be. It's due to their printed nature that I don't think aluminum body posts and lexan bodies will be a good match- the JConcepts body mounts have a lot of give to them, aluminum would just turn into prybar in rollover.

I tried to use as many standard components as possible, not choosing difficult to acquire stand off sizes and such so that if the day should ever come that I give up on making these the design can become public domain and if someone is really interested they can have the pieces cut by one of the various on-line service providers. the baseplate doesn't need to be brass, but the extra weight down low can only help. I could run that in 1/4" thick as well for guys not running the center servo- there's only so much room between the servo horn and the battery plate.

As for the Bullhead, I'm reasonably certain it will fit, but I don't have one to test. One of these days I might buy a broken old body to test it, it's possible there might be a slight conflict between the smooth sloping curve of the top of my chassis and the angled plastic inside the fender well of the body, and I've got a feeler out there for a quote on red G-10 sheets, although it doesn't look like that will be cheap for sheets this large. Worst case I'll just design some spacers to fit under the body mounts for a little extra clearance I suppose.

Thanks for the kind words guys, this has been a ton work work.

[MadAnt]

27 minutes ago, Wystan Withers said:

if I had to guess there's 10-12 hours 'labor' in each kit

I think the price sounds great, but there is definitely some streamlining needed for full production if you ever decide to take that route. Anyway, very cool.

[Wystan Withers]

A lot of it overlaps. For example running the 3d printer for two hours while running the CNC the same two hours technically counts as 4 'machine hours', and I can use that same time to tag and bag hardware, but I'm certainly not in a position to run out batches of several dozen at a time like like a commercial vendor. And obviously the time spent babysitting the CNC is prime hours to spend designing other parts so it's not a total waste. 

[Mad Ax]

I'm absolutely loving this.  A lot of people have designed their own clod chassis (myself included) but to build it with the intention of making it a sellable conversion kit that doesn't require loads of aftermarket parts and works well with stuff that's already out there?  And all that customisability re: servo, battery, etc?  That's just awesome.  Fantastic work, and I hope you get a few sales.

[mtbkym01]

Wow this is great. Make me want to consider another clod to build with one of these kits!

[2qwik]

Wow top stuff. I was contemplating a custom Clod and will definitely use this. Thanks a bunch for the idea, effort and result.