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Let's start with a back-story. It begins with a TXT-1.

It begins in early 2007, when my love of Tamiya RC was kicking up a gear and I was buying pretty much everything I could get my hands on. A bit of spare cash came my way, and was rapidly swapped for an NIB TXT-1.

Around about this time, I also found myself interested in the blossoming scale truck thing, as well as the interesting new sport of crawling. Figuring the TXT-1 was better as a hulking great impressive beast than a dedicated rock crawler, I put in an order to Stella for a Super Clod Buster and a TLT-1.

The original plan was to use the Super Clod body on the TLT axles to make a cool-looking scale truck, and use the Clod axles on some UPVC cable trunking to make a super-twisty stick crawler.

The clod body got parceled away from place to place and finally made it into Project Ringpull (on those TLT axles) almost exactly 8 years after they came into my possession, but the clod axles never made it onto the stick crawler.

And so we must go back to that TXT, and its bizarre habit of lifting a wheel under power. I could never get into that, and I could never drive around it. I guess I just gave up enjoying the TXT. And I wanted more power.

So the clod axles got assembled, along with my own special attempt to lock the diffs - two self-tapping screws pressed into the gears before the axle was assembled. Well, it seemed like a good idea at the time... Swivel hubs from the TXT axles were relocated to the Clod axles so I could run TXT wheels, HPI 550 motors were fitted, one re-timed for reverse rotation; a HPI GT speedo was stolen from my 12-cell Wild Dagger, the TXT gearbox was removed, a modded set of four-links was made and two NiMH battery packs were taped to the TXT chassis to power the whole thing. And what a heavy old beast it was.

It soon became apparent that it was too short - the top-heavy chassis would wheel-stand and flip on command, but otherwise was impossible to drive. More money was spent on extended bottom links with integral shock mounts, the TXT cantilever shock system was junked in favour of conventional upright shocks. Original ball-ends were replaced with G-made ball-ends, on the basis that they were about as strong a ball-end as money could buy at the time.

The result was a heavy, cumbersome, fragile truck that was almost impossible to drive and broke on every outing - usually a lower ball-end. I remember once carrying the whole heavy lump 15 minutes down the road to play at an abandoned BMX track and broke a bottom link after the very first jump, and had to carry it all the way home again. Also, quite predictably, my diff-locking technique royally failed and the screws came out of their homes and started rattling around inside the gearboxes, doing all manner of unseen damage.

Not long after this would have been around the time when all my MiMH batteries started to have charging problems, and the 14.4v setup seemed to pull too much out of them. I took a 60 minute drive to a great bashing site to hook up with some other TC members, only to find all of my packs had peaked prematurely (oo-er) and only had a fraction of full charge. That must have been in 2009 or 2010, and was probably the last time it got used. It was shelved (with another broken ball end) and not touched since.

I can't say I'd forgotten about the TXT/clod hybrid, because to be honest, even someone who hoards stuff like me can't forget owning an RC that big. I often found myself thinking about a rebuild, but memories of broken rod-ends and dumping packs and desoldering motors always put me off. Somewhere down the line, my project plans were all going wrong. I needed space, and time, to rethink.

In mid-2015 I found myself placing an order for some new Traxxas 550 motors - especially since they do one which runs in reverse. And then a used lipo-safe Traxxas ESC came up for sale on here, so that was added to the collection. It appeared that there was a project in the works.

February 2016 arrived, and the entry forms for the Iconic Revival were posted online. And I entered a Clod Buster into the monster truck race.

So there's a deadline, there's a set of axles, and there's an idea.

I've been looking for a good name, and Budget Buster has come to mind. I'm not sure I really like it since it doesn't suit the shell I have planned for this, but it probably fits. The general idea is that I already have most of what I need to make the truck run under its own power, so it'll be a low-budget build. On the other hand, I've been at this for just one day and have already spent a significant amount of cash. After promising myself that I wasn't going to buy any RC stuff in March. And we're only 17 hours into March.

This could be interesting.

So, here's the ultimate goal:

Build a clod-axled racer using, where possible, parts I have in stock or can make myself. TVP chassis should be lightweight to reduce stress on ball-ends and should allow fitment of 4s lipo power for the Traxxas speedo. Batteries to be mounted low on bottom deck, radio and speed on top deck. Soft springs for landing big jumps, low-slung chassis for lower COG. 2 channel 2.4GHz receiver for front steering only.

Shell will be something from my parts bin that hasn't had an outing for ages, but might get a bit of a makeover using a technique my wife found online and used for making something totally, totally unrelated - but oh, so cool!!

And here's how we're planning to get there:

Pull the axles off the TXT chassis

Strip axles, remove stupid screws, clean and rebuild gearboxes

Reassemble axles using Clod steering hubs and Clod wheels and tyres

Fit Traxxas motors

Lock out rear steering

Repurpose a TVP chassis from parts bin, make custom upper and lower decks from delrin

Make new 4-links for an aesthetically-pleasing length

Remodel my monster shell and mount low and sleek over the chassis for an evil look

Fit Traxxas ESC and radio, go find some wipe open space and have fun

A new pair of tyres has already been ordered. I have the original (unused) Clod wheels and tyres, but one tyre was destroyed while I was experimenting with a crazy idea I had for getting traction on rocks. I considered going with the new Proline Destroyers, but since this is supposed to be a budget build and I only need one tyre, not four, buying a pair of Tamiya tyres was much cheaper. I also ordered a bunch more 2.4GHz receivers as I've run out, again! I seem to have far more runners than I ever actually run, but can't ever justify stealing a radio out of anything. How does that work, eh?

So where does it begin?

Well, today I nipped home from the office at lunchtime, pulled the old TXT/Clod hybrid off the shelf and started stripping off the axles. Here's what the old thing looked like after several years of being cannibalized for parts:

IMG_20160301_131840351_zpsypjgqs92.jpg

Note TXT chassis, TXT wheels, abundance of dirt from last run

Axles came off nice and easy

IMG_20160301_133105389_zpsfgsrlxdg.jpg

Front gearbox disassembled. Those screws came back to haunt me - note one completely missing tooth. New front gears required - so that's one gearbox that won't be reassembled today. The rear had missing teeth on the bevel gears, and since I don't plan to lock this one out yet, there's nothing for it but to replace them too. I could have got away with just one gear set but, since both axles are apart and there's a bit of wear on all the gears from those stupid screws dancing about, and I want this truck to be reliable, I figured I might as well buy two new gear sets and rebuild both gearboxes fully.

IMG_20160301_134036133_zpsrs4t1cly.jpg

That's about all I have time for in a lunchbreak, especially as I knocked a pot of screws onto the floor and had to go find them, but the new gears should be with me in a couple of days and it won't take long to get the axles back together.

Then I'll onto making that custom chassis.

I suppose I need to decide what chassis to use - I have some AX10 plates which should work really well if I make some nice wide decks from Delrin, or I have a K2-3S chassis that's pretty much ready to fit and use right away. The K2-3S will be tougher and allow a more upright shock mounting position, but will be marginally heavier than my AX10 idea and will have a higher COG since I'll need to keep the chassis ends clear of the axles on full compression (or chop down the chassis a little).

And that body needs sorting, too... And I have something special lined up for that which I just can't wait to share with y'all :D

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oops, I actually intended this to go in Projects - so busy typing I'm not looking where I'm posting! -_-

Had notice last night that a few things have been posted, so hopefully I can crack on with this build towards the end of the week.

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Another oops moment - I discovered this AM that there are two types of Traxxas EVX-2 speedo, one which is lipo-safe and one which isn't. That's annoying, since when I researched before buying the 2nd-hand speedo, I only found reference to one EVX-2. I guess Traxxas only have data on the latest model on their website. Or I didn't look hard enough. Anyway, the one I have doesn't have the "low voltage protection" text on it so it must be the earlier one :(

I only bought the EVX-2 because I thought it was lipo-safe, and the HPI speedo I was using before isn't.

Looks like I'll have to invest in some lipo alarms because I can't stretch the budget to another speed controller :huh:

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I wish you good luck. These big trucks can be such a tricky balance. Their sheer size makes them heavy by nature. Bringing all that weight under control, handling-wise, is tough. They take a lot of power to get moving which is hard on the drivetrain. If you lighten them too much you may lose durability but too much weight breaks things too. I had a 14.4/550 setup in a stock TXT-1, and while nothing broke, things just wore out. I wound up using a Castle 4600 Sidewinder in my TXT-2 and programed the ESC for easy launches and a slow ramp up to full speed to save the drivetrain. So far, so good, but its still a cumbersome beast.

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Always wise to change the old plastic gears anyway - i reused one set in a mod Clod only for them to shatter on first use (and at low throttle too !). Replaced with a new set and a RC4WD steel locker, no problems since.

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So my new gears arrived this morning and my new tyres last night. I was going to do something else at lunch but I could probably nip home and have the axles rebuilt before the end of my lunchbreak. That gives me a head-start towards starting on the chassis on Sunday evening after I get back from a weekend away.

I still have no idea how this is ultimately going to turn out - in my head I see an awesome, low-slung, fast, smooth and reliable monster racer, but as usual I'll probably end up with a ropey, bad-handling, unreliable bucket of random parts :P

More pics to follow when I've started reassembling :D

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If you were considering going back to a single central servo and 4WS then using a shorter servo arm hole location for the rear will reduce the throw to the rear steer. this still gives some 4ws effect , but reduced rear steer for a little better stability. Turning circle isn't great on a front steer only Clod, even wih the tabs shaved on the hub knuckles.

I'd suggest you try to keep the wheelbase around 13-14" as this will give you the best choice of bodies; the Killerbody Rubik shell (pretty cheap from modelsport) fits that length fine, and is a bit narrower than the usual go to Emaxx bodies which are often quite wide and foul the wheels if not set high.

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OK - so this weekend didn't go entirely to plan. I had to skip lunch on Friday due to a major problem at the office, so I didn't get to reassemble my axles :(

And then due to not checking the tickets properly, our weekend away got cancelled too :( :(

But the wife decided to go out for the day on Sunday, which gave me the whole day to myself to crack on with some RC projects :D :D

So I removed the old gears and fitted new. After much deliberation I decided to lock both diffs, but I used hot glue so it'll be easy to reverse the change if I need to. Plus, if the glue does manage to work loose while assembled, at least it's soft and shouldn't roll around damaging the other gears. I looked out the original Super Clod swivel hubs and associated hardware and used the Dremel to take off the steering stops on the front axle, for just a little more turning ability.

Axles reassembled, I dragged down my old wheels - I say old, 3 of them have never been out the packet! Two brand new tyres fresh from the shop fitted up fine, the two tyres that came with the original kit, never fitted, have faded and gone powdery and were much harder to fit - but they got there in the end. I'm sure they'll be fine once they've got some dirt on them.

Here's the assembled axles - note different in tyre colour!

IMG_20160306_170840554_zps7h6nsu4x.jpg

By that time it was getting pretty darned cold outside and the sun wasn't far off setting, so I decided to call it a day - but not before lining up some other parts. Here's my old K2-3S chassis - might be a good donor for this project:

IMG_20160306_171116853_zps2ewv4qb1.jpg

I'll have to see how it looks once I've cut some links...

Here's some teasers of how the finished project might look - this crazy body was once a Parma El Camino from a drifter, I cut off the arches, sprayed it matt black, chopped up a latex Halloween mask and glued it on. I have a great idea for some finishing touches to this shell but they can wait until after the chassis runs properly.

IMG_20160306_171243868_zpsxktnukai.jpg

IMG_20160306_171300152_zpsrdkkkkhe.jpg

I still haven't decided if I should stick with 4WS or lock out the rear. I don't want to have to go back to my 40MHz stick radio, I can't really justify buying a 4ch 2.4GHz stick radio and can't run independent steering with my 3ch wheel radio.

:)

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If you have plenty of room where you intend running it then 2ws with the locks tops off isn't too bad, but you'll still have a large(ish) turning circle !

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Your turning circle will be worse with locked diffs also, and it will put more strain on drive train components than if it was open. You could try Anti wear grease or similar on the diff gears?

That powdery stuff on the tyres should just be the release mould agent, if you sprayed it with a citrus cleaner and gave it a scrub with an old toothbrush it should come off.

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Regarding 4ws, i did get a y-cord and a signal reverser for my CR-01, that made me get 4ws using a 2ch radio. didn't cost me much. Could that be a solution for you?

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I'm starting to think I'll have to have 4ws of some sort, and besides, Clods are so much more impressive when both ends turn :D

I was thinking this morning about digging the old 40MHz transmitter out - I haven't used it in years but it was reliable enough when I was last running the Clod.

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That looks like an awesome bit of kit! :o I have a 3rd channel toggle switch on my wheel controller and I wasn't intending to use ch3 for anything else on the clod...

BTW - no updates this week as I've been busy with other things, going away this weekend but might have time to grab some more threaded rod from the hardware store and cut my links on Sunday :)

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Wow, it's a while since I've been here!

So the last episode ended with me going away for the weekend and not having any threaded rod. Well, I did go away that weekend, but I didn't have time to get any threaded rod. In fact I've been busy over the last few weeks with a custom drift project (see Builds section), which led into some serious DIY time at home. In fact the whole Clod assembly got put into a storage crate and put up into the garage roof out of the way.

Well, today I managed to escape from the office for an hour to go buy some threaded rod. Two lengths of B&Q's finest M4 rod and two lengths of allu tubing to cover them. This gives me something I can pick up on the odd lunchbreak here and there, just to keep the momentum going :)

Watch this space!

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OK - so it's been a while!  What a crazy summer, both for RC stuff and for other stuff too!  So I didn't get the budget clod finished in time for the Revival, but that's OK because I had a King Blackfoot as a backup option and it was good enough to hook me 3rd place in the race.  Well, I say race, I only got 3rd because I was concentrating on going around the track while everyone else was busy running over shells and getting tangled up with each other.

But never fear, Budget Buster still lives, and with all of this year's RC events now well and truly out of the way, it's time to get back to some of these outstanding projects and see if I can't actually finish something for a change.  So, which project did I pick to finish?  One of the ones that's taking up space on the hobby room desk?  No, that would be obvious.  It'll be this one, which was neatly boxed up months ago and put out of the way on the mezz in the garage.

So down it came last week, and after a couple of evenings I'd managed to make a chassis jig and chop up some M4 allthread.

Jig cut to length:

IMG_20160814_181341902_zpscaj1d2nf.jpg

 

Axles mounted in jig to hold them in place while everything else is measured:

IMG_20160814_182220930_zpsd7ivhh7e.jpg

 

Chassis balanced over jig for measurements, top links cut and fitted:

IMG_20160815_195650090_zpsgtzmbiu0.jpg

 

Bottom links fitted too.  starting to look like a solid axle monster truck now:

IMG_20160815_203525372_zpsdwwuz09f.jpg

 

That took me up to close a few days back.  Today I had a spare lunchbreak so I popped home to mount up some shocks.  Pics to follow.

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I bought these shocks many, many years ago for the TXT.  For some reason I bought two sets, so these ones had never been out the pack.  Perfect fit, but the springs feel a bit too firm.  Maybe they'll be OK once I've got all the electrics and batteries mounted.  Shocks at full extension makes the wheelbase a bit shorter than planned but still looks cool, and will be fixed once there's more weight over the chassis or softer springs in the shocks.

Glorious beaming sunshine today, a nice alternative to the non-stop rain we had at the weekend:

IMG_20160823_133837385_zps8o93vate.jpg

 

Wheels mounted to check clearance:

IMG_20160823_134237861_zps2fjg334u.jpg

 

Body plonked on top just to get a feel for how it might look.  Will probably have to raise it a little and cut bigger arches.

IMG_20160823_134403097_zpsbiqsk5s3.jpg

 

Gonna look seriously mean when it's finished:

IMG_20160823_134419055_zpsp9q9tkdn.jpg

 

Still to do:

Remove rear axle, trim out lock stops like I did with front axle, re-fit axle

Find matching servo for rear axle (I have it somewhere) and fit to rear axle

Sort out some body posts and mount the shell

Trim the shell for full articulation and steering

Figure out a battery mounting position and strap arrangement

Hook up a pair of silvercans and a basic speedo and give it a test-run on 2S

Consider if it's worth fitting 550s for 3S or 4S running

Clean up the shell for final detailing

Detail and paint the shell

Fit 3S / 4S power system if I decide it's worth doing

Balance the springs against the final chassis weight

Go play

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Like a boss I love it B) txt-1 shock springs are crazy stiff some softer springs will soon sort that :)

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Shell looks great. I don't think I'd be alone in thinking that it needs two little beady red eyes in the form of LEDs just to add to the effect though! 

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I had a crack at getting this closer to running last night, but came up against some obstacles.  Firstly, I can't find the matching servo to get the rear axle steering worked out.  If I wasn't on a budget I'd just buy new ones but I'm supposed to be cutting back on spending now.

Also had an issue with my servo mounts - I didn't notice before but they foul the wheels on full lock.  I guess this wasn't a problem last time I was running these axles because I was using TXT wheels; the clod wheels have less offset so the tyres are closer to the servo mount.  My first thought was to go buy some vertical servo mounts, but I'm back to not spending too much money, as well as not wanting to wait from delivery from the US.

It's just occurred to me that my current servo mounts could be installed vertically if I modified them, or used them as a template to make new ones.  Although I'm a bit limited on fabrication time too these days!

I also remembered I need to cut some spacers for the lower link to chassis mounts, they were obviously cut for much bigger rod ends before.

I was hoping this project would slot together quite neatly and be a quick bench-to-runner project once the links were made, but it's gone the way of most of my projects and is looking set to take a little longer :P 

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For rear axle steering do you mean you have a modified servo already? I had to swap the wires over on the inside of my servo for my dual-steer WR01 project, which was easier than I thought it would be. My servos were only the cheapest metal-geared Hobbyking items too, and they seem fine! (if a little noisy)

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4 hours ago, ChrisRx718 said:

For rear axle steering do you mean you have a modified servo already?

I don't have a modified servo, I use a 4ch radio so I can steer both ends independently.  I'll have to get used to being on 40MHz again though as I can't justify a multi-channel 2.4GHz transmitter.  Although it's possible my Spectrum wheel controller will allow some kind of mixing, I'll have to investigate that...

But what I meant is, way back in the day when this was last running, it had matching servos front and rear.  Now it's only got one on the front axle.  I guess I borrowed the rear one for something else.  They were TowerPro metal gear servos, which were pretty much the go-to choice for big torque on a small budget in those days.  I did spot one attached to Project Ringpull but it looks far too clean and tidy to have come from my Clod :D

Anyway, the point is moot until I can figure out what I'm going to do with the vertical mounts.

I also noticed last night just how bad the axle angle is, I must have got my measurements way out when I cut the bottom links.  I might have a whole nother set of links to cut yet.  Not sure I want to tho, I quite like the little stubby wheelbase :D

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The bonus with living only 10 mins from my office is that I can get 40 mins of spanner time during a lunchbreak when there's nobody else in the house to get in the way.

Today I nipped home to have another look at the servo mount on the clod project.  20 mins stripping down and 20 mins on the bench drill (including the time it took to walk up and down the garden twice) and I had this:

IMG_20160830_134858356_zpsrmjp5gvf.jpg

 

I just measured up where to drill a 3mm hole, then made up some spacers from cheap alu tube that I got from the hardware store.  Fits onto the standard gearbox crews.  I've got another one all made up ready to go on the back, then I should be able to fit the servos and get the steering working :)

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So I've been having a few issues with this build.  Namely, complete lack of clearance anywhere since I swapped back to the stock Clod wheels.  I love the look of the compact, narrow track so didn't really want to have to buy spacers or refit the TXT wheels (trying not to cannibalise TXT parts as I'd like to rebuild it at some point).

Anyhoo, on full articulation and steering lock, the wheels rub on the shocks.  I'd considered narrowing the chassis by cutting down the Delrin blocks, but clearance between lower arm and 550 motor is really close so I figured that was a no-go.  I can't mount the shocks inboard of the chassis because there's nowhere to mount the shock bottoms, so the only solution was to reduce the spacer size on the shock tops.

I managed to find some nice alu spacers that much has been from another shock set and bolted 'em up.  Now things are much better.  Except the suspension is now binding.  Why, you ask?  Because the cheap shocks don't have pivot balls on the top, they have cylindrical pivots.  So the shocks will only move on one axis.  Short of going out and buying new shocks (there really is no budget left for this truck now!) my only option was to space the lower mounts inwards with some little spacers made of alu tube from B&Q.

IMG_20160911_165531548_zpsvbmkavdw.jpg

 

New Alturn high-torque servos arrived at work this week but I haven't had time to fit them yet.  Next on the project plan:

  • Fit new servos
  • Make steering links
  • Make radio tray
  • Make battery retainer
  • Fit all electrics

And of course, there's still the shell to finish off...  Big plans here - would be nice to have it done before the end of the month as I think I can make it work with the "black" theme ;) 

IMG_20160906_134934215_zpspnisp6ns.jpg

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Those shocks look to be the same brand as the set I have on my df02, been meaning to check and see if the plastic inserts on my serpent sct will fit nicely in the upper point.

I'll try to get around to that this weekend and let you know, only thing I can say is, being a serpent part, they won't be all that cheap, but will give you a starting point reference if they do work :)

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