Big 6 - Custom 6x6 Element Enduro Scale Builder's Kit

[Mad Ax 10847]

Thread title renamed - was: Project Top Secret - Element Enduro Scale Builder's Kit

OK - the project name and outline for this one is still top secret, until next week, and in fact I've been calling it Top Secret for so long that I might actually officially name it Project Top Secret anyway.  But for now, I want to get some of the highs and lows of the build out of the way, as there have been a few.  This isn't a full build thread - I get bored doing those and I'm sure somebody has already done one.  Instead this is a highlight reel of the past few months.

Let's start with a little bit of backstory.  I bought my first Element Enduro Scale Builder's Kit from the Racecraft RC pit shop at Revival 2021.  I'd just finished building a GMade BOM, and loved almost every minute of it; before that I'd built an MST CFX-W J45C, and enjoyed that too.  Both cars had been bought with a bigger project in mind, but upon building them, I realised they were more suited to plain trail duty - not because they weren't capable enough in their own way, but because the cost of buying the extra parts I'd need was prohibitive, and because the way the chassis were designed made it hard to work out how I was going to get everything to fit.

Luck came my way towards the end of 4WD Sunday (to be fair I didn't have much luck during the race, finishing some way down the order with a Manta Ray that shredded parts in every race, preventing me from getting a good setup).  My number came up in the raffle, landing me with a Black Edition Lunchbox that someone had bought from Racecraft RC that very morning, and donated into the prize pot.  As please as I was with my win, I already have a lunchbox (well, my daughter does), and I already have a WR-02 that (IMO) is a better solution to the wheelie vehicle problem.  So I took it straight back to Racecraft RC and traded it in for the Element Enduro.  This seemed to be the perfect donor for the project I had in mind, as all the parts are available in neat modular sets, and Adie can get them in stock at the local shop - it's convenient that Racecraft RC is not only the official pit shop at all Iconic events, but also only 30 minutes drive from home.

Now, onto the key features of the Element Enduro, and the highlights (and lowlights) of the build...

[Mad Ax 10847]

The first lowlight came before I'd even opened the box.  I knew I was going to need extra parts for the build, and after pricing them up, I realised it would be cheaper to actually buy a second kit.  I went online to check availability, to discover that the Scale Builder's Kit 2 had been released.  Much the same as the original kit in all key areas, the main differences are different shock towers with more adjustability in shock location, adjustable panhard rod mount, and gorgeous bronze-coloured shock bodies (so much nicer than the cliché anodised blue of the old ones).  Disappointingly, this meant if I went with another SBK1, I'd miss out on the better parts, and if I went with an SBK2 I'd have mismatched parts altogether.

Another expensive issue occurred when I got some money in from a side-hustle and went to buy an SBK2 from Racecraft RC, to discover the price had gone up by £60 in a week.  We never got to the bottom of this mystery - Adie's SBK2 box has a different part number to the order book, and when I eventually got another SBK2 from a different reseller (don't tell Adie), it was at the old low price.  Perhaps Adie's one has gold-plated nuts or some additional hop-ups?  One day I'll pluck up the courage to ask him about it.

Anyway, I didn't get around to starting the build until April of this year.  I was on a Daddy Duty day, but my daughter was happily playing by herself in the garden, and the sun was shining, so I dragged over the cracked old wooden table, pulled down the SBK kit box and cracked it open.

First impression: these SBK boxes are compact.  There's something very impressive about a huge kit box with massive tyres and a full body inside (the SMT-10 box doesn't even have that, and it's not a small box  ) but these smaller kit boxes are nice too.

Second impression: scale workshop included!  I've seen these online before but didn't realise they were the inside of Element RC boxes.  For years I've wanted to make a scale workshop, but never got around to it, and while I like the idea of doing my own take on it, this definitely makes it easier and more accessible.  I've got the perfect spot for this once the project is complete.

Third impression: I love the intro blurb in the manual.  I'm not usually taken in by marketing speak, but something in the Element RC book seemed to be talking directly to me.  After being forced down a very narrow path by RC kits for years, and having to break out the Dremel and hacksaw to do my own custom take on everything, the Element RC intro blurb is entirely about doing it my way, however I want to do it.  I like that.  Model building should be a personal thing, and this promises just that.  Of course, marketing speak is just that if none of it turns out to be true - just look at how many Tamiya cars have been labelled as "high performance off-road racer" or whatever - so it was time to start building and see what I'd gotten myself into.

Fourth impression: referring to the build steps as "gates" is either cheesy, funny, or lame, depending on your point of view.  I haven't made my mind up yet.  The "individual bag per step" thing is nice, but also sometimes wrong - at times you have to save some parts from an earlier bag to use in a later step.

Fifth impression: this isn't as much of a clone of the SCX10 as I'd been led to believe.  The first time I saw an Element Enduro, I was told it had been designed by someone who worked on the design team for the SCX10, and it was basically a more rugged, customisable evolution of that chassis, taking a slightly different direction to the more scale-correct successors from Axial, Traxxas and MST.  But these chassis rails tell a different story - those hard angles over the front axle aren't like anything I've seen before.  The panhard rod and servo-on-chassis steering is more of a nod to realism than the original SCX10, or the CFX-W, too.

[Mad Ax 10847]

I made a few mistakes putting the chassis together.  At one point I had the battery tray at completely the wrong end, I had to disassemble the entire chassis to relocate it, then realised I'd got some other parts wrong too.  I wasn't really rushing (it was a lovely sunny day to be sat outside), I just probably wasn't paying full attention - if memory serves I was feeling a bit ill that day - and the images aren't entirely as easy to follow as Tamiya's instructions.  The screws are long and stiff, too - like most modern kits, this uses machine screws into hard plastic, which really worked the muscles and tendons of the fingers.  I resorted to using an electric screwdriver for many parts.

I'll draw your attention now to the axles.  This was one of the best discoveries of the SBK design, for me.  So many scaler axles these days look great, but are very specific to their task.  Like, modifying them to do something else would be tough.  But check this out:

This is the diff carrier in the front axle.  It's symmetrical.

This is the diff, installed:

The helical gear is a nice touch, although I'm not sure it's necessary on a scale crawler.  If my engineering knowledge is correct, a straight gear should be stronger, a helical one quieter.  What's interesting is that you could but the diff in upside down, if you wanted to.  Why is that important?  You'll find out next week, if you haven't already guessed.

Another neat feature on many modern axles - clockable hubs.  This allows the caster angle to be adjusted.  More importantly on a solid-axle scaler, it means you can rotate the axle to get a better angle on the propshaft and retain the correct steering geometry.  Probably not something I'll need on this project, but it's a nice option.

The steering arms bolt on, too - they're not moulded into the hub.  This means you can easily make custom linkages, especially if, say, you were building an 8x8 military rig and you wanted to link the steering axles together, or you wanted to play with Ackerman angles on a Dakar rally truck build for better handling at speed.

Overall, this was a very impressive build for the price.  Apart from the central-mounted motor/transmission and the angular chassis rails, it has all the scale features you'd expect on a more expensive kit.  The included shocks (while a non-scale blue colour and slightly too wide for a true scale shock) are silky smooth and easy to fill, probably the nicest out-of-the-box shocks I've build in a very long time.  Good instructions too - I struggle to build modern crawler shock without hydrolocking them, but the instructions in the Element book explain how to make them work properly.

[Mad Ax 10847]

Another point I'll make about the SBK1 - and a nod to the customisability promised in the intro blurb - it comes with enough metal links to build the truck in 3 different wheelbase configurations.  Top marks, Element RC!  So many kits pretend to have different wheelbase options, but only if you buy the optional parts or cut your own links.

Shortly after finishing the SBK1 build, I happened to spy a post on Facebook in which someone was utterly roasting the SKB2 for being a terrible, fragile, not-worth-the-box-it-came-in kit.  In fact he did literally say he was going to throw it all in the bin, unfinished, because he couldn't bare to give something so bad to another person, even for free.  His problem?  The hex heads and stripped when he was trying to put them into the plastic gears.

The response from most other users had said exactly what I would have said - be more careful, and use a good quality driver.  But this guy claimed to have years of experience with kit builds, having built dozens of models, and always used high-quality drivers.  So, someone very much like me, then.  I decided not to wade in on the thread until I'd had a chance to see for myself.  After all, by this time, I had an SBK2 waiting for me to build.

Then this happened.

Yup - that's a completely chewed screw head.  OK, I'll admit my HPI 1.5mm driver is past its best, and I'll also admit that, being an Associated kit underneath the Element branding, there's a possibility this is actually a 1/16.  I know Associated were supposed to have switched over to metric a while ago, but it's always possible some of the smaller screws remained in US dollars.  Indeed, my 1/16 driver fit snuggly in all the screws, including ones I hadn't even started to marmolise yet.

This delayed the build a little, as I need to buy some more screws (stainless, metric), plus a proper thread tap, so I wasn't relying on a tiny 1.5mm hex head to take all the load needed to cut a new thread in hard plastic.

Getting the marmolised screw out required the use of my very last Dremel fly-off wheel.

Job jobbed

[Mad Ax 10847]

After assembling the axles, I had another problem.  The rear axle was stiff - there seemed to be a tight spot in the diff pinion.  I've had this a few times with modern crawler axles, in fact it took a fair bit of filing and reassembly to get my CFX-W crown gears to turn smoothly, which is a lot more work than one expects, coming from a Tamiya background.  The Element gears were turnable until the diff cover was properly screwed in, then the tight spot became apparent.  After a few disassemble-reassemble-grumble-repeat loops, I took a closer look at the gears.  The tight spot was definitely just in one place, and occurred with every complete rotation of the pinion.

OK, so a problem on the pinion, then.

It took a real careful look to find it.

Yep - wedged in between the teeth, a tiny drop of metal.  Spherical and smooth, it looks like a molten blob from the casting process, which must have dropped in after the gear was released from the cast and got stuck there.  It took a bit of persuasion to get it out, which means it had probably been wedged in pretty hard by my continual turning of the gears.  I can't imagine it had melted in there during casting - everything should have been cool enough to be solid by the time it was released.  Then again, I know practically nothing about casting.

[Mad Ax 10847]

So, anything else to add on the build so far?

Well, the SBK2 comes with nicer-looking links made out of a dark plated metal, which is more scale than the shiny links in the SBK1, however the kit only includes the parts for the LWB version.  So, like other chassis, if you want to make a different wheelbase, you either need to buy option parts or cut your own links.

The updated shock towers, however, come with a bonus surprise.  The parts tree includes the angled shock towers from the Gatekeeper, which is Element RC's rock bouncer model based on the Enduro platform.  The Gatekeeper has its shocks mounted on the lower links, not the axle, and angled forward so the upper mount it above the upsweep on the chassis rail.  This is a super-bonus for me because I want to mount my rear shocks in a similar way.  Having seen photos of the Gatekeeper after I'd started building the SBK2, I wondered if I'd made a mistake and should have got that kit instead - but I needn't have.  The SBK2 has the parts I need.

So, you may well have guessed what I'm planning here, but there'll be a big reveal early next week when I post up my Workshop Sunday progress pics.

I want this project to be finished and drivable by the time I leave for the Scaler Nationals on 30th September.  That's two whole months away yet, but due to other commitments, that's only 5 more Workshop Sundays, and there are some fairly complicated issues I'll have to get over, as well as a number of custom parts that need fabricating.

Parts-wise, I already have much of what I need - high-torque servo, a set of wheels and tyres that practically fell into my lap at the Southern Scale Trail earlier this year, and a discounted bodyset that I picked up at the Scaler Nats last year.  I've probably even got all the paint colours I'll need.  I'll want a winch on this one - I was planning on a fancy-looking scale winch mounted on a metal front bumper, but they're either expensive or fragile, so I might get another winch servo from Overland RC and mount it in the convenient 2nd-servo space over the front axle.  A rear winch would be nice but not a deal-breaker before October, and I've probably got enough scale parts to make up some rear tow hooks (again, these are essential for the Nationals).

The biggest problem to solve will be the transmission, but for why that should be, I'll let you wait until next week.

Watch this space!

[OldSchoolRC1 1090]

Welcome to the Element club! I've got three in the mix, as well as 3 stand alone transmissions for other builds (They work great in a CR01) and they are very nice kits. Quality was well above my SCX10III kit, which was quite a disappointment. 

Those transmission gear screws are indeed a pain. After doing exactly what you did on my first build, I made sure I coated them in grease before install  for the next build - it helps tremendously. On the third and subsequent builds, I trimmed them down by about 1/3 - still holds plenty strong and not nearly as much struggle to get them in. 

Looking forward to seeing how you finish it off! 

[Mad Ax 10847]

I've just been stripping down both chassis and lining up some parts.  I think it's going to be quite a challenge to get this done for October...

I'm tempted to try one of the transmissions in my SCX10 G6 Edition.  For those new to Enduro, the gear ratio is different front to rear.  I thought this would be handled in the axles with different diff gears, but it's not, it's in the transmission.  There's two separate sets of gears, giving a different ratio at the front output to the rear.

I only need one transmission output for this project, and it seems a waste to use this fancy transmission if I'm not going to use both outputs.  My G6 is ancient and has had a hard life, but the transmission is still rock solid (it's never been apart) and might be the perfect donor for this project, assuming I can get the Enduro transmission in its place, because the G6 has come with me to every major scaler event I've attended and I don't want to leave it behind this time around.

[Mad Ax 10847]

I got a bit of extra time after work yesterday, and it was too humid to start my walk early, so I escaped the confines of the house and stood in the workshop with the back door open and the sun on my shoulders.  Which was nice.

OK, so here's where this project sits right now.  It seems I didn't bother to fit the shocks on the earlier build, but that's OK because it's all coming apart again now.

Incidentally, these are the adjustable shock hoops on the SBK2.  The hoops themselves sit a little higher on the chassis too, which must give a slightly lower stance.  On their lowermost setting (i.e. the truck in the tallest position) they're about 2mm higher than the SKB1 hoops.  This might actually work in my favour, for reasons that will become apparent later.

SKB1 hoops:

 

[Mad Ax 10847]

And here is everything I need to kick of the project:

2x chassis, a bunch of wheels (there are 4 more identical wheels and tyres in the studio), an F150 cab and a transfer box.  So, where's this going..?

Well, you've probably guessed already, but here's another cool thing that I mentioned above: the shock hoop tree includes these neat little badboys, from the Gatekeeper kit:

Fitted.  This allows me to move the axle forward a fair way to make a really stubby truck.

[Mad Ax 10847]

I also threw on that transfer case, just to see if it would fit.  The hole position is almost right - just need to redrill the plate slightly.  I'll worry about that later.  A few other mods are needed too, to clearance the case shape.

Stubby Bob!  You know, I like this look so much, I'm almost tempted to keep it just like this.  Almost!

[Mad Ax 10847]

Of course - you've already guessed it, haven't you?

Of course you have!

Another 6x6 build!

[Mad Ax 10847]

Now, I know you've got a whole heapload of questions about this, so I'll try to answer them.

Ax, why?  You've already got an F150 6x6 cab that you haven't finished yet

Yes, I know, and in many ways the F150 tow truck was a fact-finding mission before I started on this one.  These trucks won't be copies of one another, they'll be very different.  I want this one to be a very capable rig on the trails.  My flagship rig, if you will.

So, you can't trail with the tow truck?

No.  It's got leaf springs, virtually no articulation, a fragile body and cheap tyres that will probably pull off the rims as soon as they see a rocky crevice.  In truth, the tow truck is a show piece - a "because I can" piece - I doubt it will even get used for marshalling.  It's just something I wanted to build.

Why not just buy a 6x6?

Two reasons.  One, unless you go for a cheaper brand, they tend to be RTR, and I wanted a kit.  Two, because they're all too long.  I probably mentioned this when I started the tow truck thread, but the current crop of 6x6 crawler rigs look pretty useless for anything other than showing off how much money you have (pretty much like most full-size 6x6s, if you ask me).  That's not meant to be a slight against anyone who owns one - if you enjoy it then great, don't let me tell you what you should and shouldn't like.  I'm sure they're superb at straight-up climbs, too, and don't fall over backwards like most other class 2 rigs.  I'll be you can go near vertical.  But, on a real-world rock-and-mud comp course a la UK Scaler Nationals, SST or G6, they're way too long.  The middle axle sits pretty much where it would on a 4x4 rig, with the rear axle hanging out the back.  So the truck is longer by a whole extra set of wheels.  That doesn't help you get around a seriously tight corner.  Plus, your breakover angle is no better than a regular rig.

The real benefit of a 6x6, IMO, is bringing that middle axle as far forward as you can, so you don't get hung up on tree roots or rocky overhangs.  You can do that with a 4x4 (like Stubby Bob above) but then you've got a truck that'll flip over on every climb.  By adding an extra set of wheels out the back, you've got the best of both worlds - a longer wheelbase to help with the climbs, and a middle axle to reduce the chance of a central hangup.  The trick here will be getting that middle axle as far forwards as I possibly can.

It's still a little far back in the photos above.  The floor pan will need modifying, and it looks like I can't use the rock sliders (I could cut them down but they'd look odd) - I'll have to fabricate something.

So - tomorrow is Workshop Sunday, and I've got the entire day to make a good start on this rig.  5 Workshop Sundays is really not a lot of time to make this rig run, especially with Revival to prepare for and 3 other scale rigs that need to be serviced before the Nationals, but broken down into steps, everything is manageable.  It's just time.

Step 1: hang the middle axle.  Easy - just cut new 4mm allthread.  Should have that done tomorrow.

Step 2: hang the rear axle.  Harder.  Need to work out mounting points - probably the crossmember above the centre shock hoops.

Step 3: extend the chassis to mount the rear shock hoops.  Got a few ideas but nothing concrete yet.

Step 4: route the propshafts.  This could be tricky.  Real tricky.  Fingers cross this isn't a dealbreaker, otherwise I'll be driving a stubby truck after all  

Step 5: hang a transmission up front.  Wow, that's going to be tough - I don't even know what transmission I'm going to use yet, let alone how I'll mount it.  Space is limited because of the chassis-mounted steering servo, so it won't be a full up-front transmission, it'll sit probably where the battery tray is now.  I might have to invest in something very small.

Step 6: put the whole thing together with electrics and winch and painted body, and go crawling.  Somehow I expect I'll be putting it together in the hotel room the night before the Nationals.

Should have step 1 done easily tomorrow, if I can get step 2 done as well, that's a major bonus.  If not, I want to at least be well on my way with it.

Here goes  

[Nikko85 3955]

Awesome. 

Quick question, can you move the front axle back to also achieve the same thing?

 

 

[Mad Ax 10847]

10 hours ago, Nikko85 said:

Quick question, can you move the front axle back to also achieve the same thing?

I can, and I have been considering it.  It might help with chopping the floorpan and rock sliders.  I'll need to check the chassis to see if there are alternate mounting points for the shock hoops and servo mounts, as it's a panhard assembly at the front end and the geometry will be upset if they don't move too, so it's slightly more work than cutting new links.  I know the back end has various shock hoop points, if the front does too then I save myself a little more work

[Mad Ax 10847]

OK!  I'll be updating this thread slowly through the week when I get a bit of time here and there, but Workshop Sunday was hugely productive and I achieved so much more than I expected.  But let's start at the beginning.

This is where I began.  A built Enduro SBK2, with the rear axle roughly plonked where I wanted it to be.  I have chosen to mount the body a little further back, as this allows the front axle to fully turn and articulate without hitting the rear of the arch.  Obviously the whole front part will have to be cut away, but I think that looks better than cutting all of the arch away.  Also this gives me the option to pull the front axle back later if I want to, as per @Nikko85's suggestion.  I haven't decided if I should cut the body to fit over the chassis or cut the front of the chassis off - probably the former.

I'll line the rear of the body with the rock slider mounts.  That makes for an easy cut and means I can still fit some sliders later.

If I cut the bumper off the body (the arches need to come off anyway) it'll fit over the chassis.  Then I can add a proper crawler-style metal bumper.

Should be loads of space here once the body is mounted flat.

[Mad Ax 10847]

I trimmed the unwanted part off the floor pans to get clearance for the middle axle

Then I measured my wheelbase, and made a jig to hold everything in place while I made my new links

[Mad Ax 10847]

I use a piece of string to work out the length of the lower links.  It's not perfect (in fact I had to make more than a few adjustments) but it got me in the ballpark, and it much easier to use than a tape measure or solid ruler.

Fitted, with stock angled rod ends

Top links made in the same way

The result looks neat.  I'll disassemble and fit some tube over the links when the project is finished, for now this allows easier fine-tuning

[Mad Ax 10847]

His name is Stubby, and I love him

(actually, with a bit of lateral thinking, it will be really easy to design the back end so I can detach the rear axles and run a Pure Stubby, should the urge ever take me.  And I think it will, because Stubby looks so cool.)

[Mad Ax 10847]

I cut down a standard propshaft and hooked it up to the transfer case.  The angles are quite aggressive but they work without any binding.

At this point, everything was pretty straight-forward.  I mean, all I did was cut some bits of threaded rod.  If I couldn't have had this stage done on Day 1, I might as well have handed back my hex wrench.

Now things got a bit more complicated.  Brackets for the lower links, to attach to the forward rear crossmember, which is right above the middle axle.  I could have gone further back for shorter links, but they would either be right up on the highest part of the chassis, or sitting on a drop bracket that will get in the way of the ground.  Anyway, there's no real problem with long links - at least the articulation curve will be fairly flat (unlike the middle axle with its stubby links).

I was running out of M4 stainless rod (more on order!) so I found these really old TXT links that are pretty much the right size

I had just about enough rod left to cut the bottom links, which was lucky, or it would have been a fairly short day  

[Mad Ax 10847]

Seriously, that's not bad for half a day's work!    OK, so the rear link lengths need fine-tuning, and the axle isn't perfectly square yet, and the rear prop is going to be difficult, but, it works, it articulates, nothing binds on anything else and there'll be enough clearance between middle and rear wheels at all possible articulation angles once I've sorted the lower link length out properly.

[Mad Ax 10847]

After hanging the axle on its links, I figured I needed to mock up a shock hoop to see how it looked.  I opted to use the hoops from the SBK1, because they're a bit lower, so they should like up neater with the top of the middle axle hoops.  It's just a shame they don't have the same adjustability - all this back end is likely to be on display, so it would be nice if both sets of rear shock hoops matched.  Perhaps I'll see if I can make something later.

I used a crossmember from the back of the other kit for this mockup.  Don't panic - this is just a mockup, it won't hit the trails like this.

I've got some 8mm alu square bar on order which should allow me to build a channel extender.  I was going to chop the back off the other chassis rails, but it's such a small section I don't think I'll bother - they're nice rails and I'll keep them for another project some day.  I can probably fab up a complete back end from alu parts, which will be strong, lightweight and completely out of keeping with the rest of the chassis.

Now...  onto the transmission!

 

[Mad Ax 10847]

I grabbed my ancient SCX10 G6 Edition from the house and whipped out its original transmission.  It's been in there, much-abused, for (at a guess) 8 years.  It's done several Scaler Nationals, several G6s, two Southern Scale Trails and a whole bunch of smaller events.  It's never even come off the tray before.  There was mud under it that could probably be carbon dated.

And yet, when I flicked the slipper shaft, it span as free and true as a vinyl turntable.  Super-smooth, no play or grinding, not even any appreciable wear on the spur.

It's a lot smaller than the Stealth X from the Enduro, too.

eew

[Mad Ax 10847]

For reasons that I can't fathom, I took absolutely no pics of the process of fitting the all-new unrun Stealth X transmission in the SCX10.  It was almost a direct swap - the bolt pattern is only slightly different, close enough that by running a 3.5mm drill through the wider holes I could get the screws to line up properly.  I had to shorten the front propshaft because the new tranny is longer, and I had to relocate one of the little wiring clips that attaches to the chassis rail on the SCX10.  Otherwise, it was just a matter of hooking up the props and going for a test-drive.

The Stealth X is aptly named - it's very quiet, considering it's got two sets of gears.  It makes a lovely purring sound.  Did I really notice the 5% rotational speed difference on the 1:10 scale mountain?  Well, no, not really.  The entry point to my mountain course it steep, and there's a tendency for the rear wheels to drop in and lift the front of the truck.  I'd hoped that the faster front wheel speed would help it claw its way over this obstacle, but it didn't really make much difference.  There's alternate gearing included to go to an 11% overdrive on the front, which might be better, but I don't know if it'll be more obvious on the pavement or even put the old axles under too much stress when blasting between courses.

On the subject of axles - I checked the gear ratios betwix'd the Axial and Element diffs, but they're too different to be mixed and matched.  So, there's a spare steering axle sitting around doing nothing.  If I but another rear axle kit I could make a whole new crawler or monster truck out of spares left over from this build, or I could buy a Gatekeeper and build it with the optional IFS front-end (I have an urge to make a fast Gatekeeper, more like a scale racing buggy than a rock bouncer), and then I'd have two steering axles, to make a 4WS monster truck.  But I'm not supposed to be planning new projects or setting myself up for more purchases - I've got no money left after building this one!

[Mad Ax 10847]

I'm going to make an interlude here to bring up an interesting point.  Last week I was wondering what motor I should install in this rig, as I don't yet have one.  I was looking on the Holmes Hobbies website for recommended motors, when I stumbled across a note that said "reverse rotation."  I hadn't seen that in any other Enduro documentation, so I did a search online.

So, as the story goes (and I am not quoting directly here, just summarising what I found on other forums), the transmission was originally made with the motor hanging out the other side - like some other crawler trannies - with the current configuration being an option for lower gearing.  However, in product testing, it was found the lower gearing was more desirable, so that's how it was packaged, and that's why the transmission rotates backwards.

Except, it doesn't.  Well, it goes the same way as the SCX10 transmission does, and that has the same general layout (see pics above).  The output shafts rotate in opposite directions to the motor.  Which is all fine and dandy, right?

Except, the Enduro diffs turn the other way, so when you put the transmission in the car with a standard motor on, it runs backwards.

The generally accepted solution for this - if you don't want to buy a specific reverse-rotation adjustable timing motor - it to resolder the motor leads.  And that's fine for most crawler motors because they have static timing.  But, what if you wanted an advanced-timed motor?  Not all of them come in reverse timing form (see any thread about Clod power options).

Well, here's the daft thing.

1) the diffs can be mounted either way around.  You can reverse the drive direction without playing around with motor wires at all.

2) the centre plate comes with pre-drilled holes to mount the transmission in either direction.  You don't even need to open your axles, you can just flip the transmission around.

Quite why this truck entered the marketplace with a requirement for a reverse-rotation motor when there are two obvious ways to solve the problem that were already engineered into the chassis before the problem even existed and come with absolutely no appreciable disadvantage whatsoever* is completely beyond me.  I'm also amazed that nobody has mentioned this before.

I'm now tempted to go and pull apart an axle and flip the diff just to make absolutely sure it will work, because my entire build pretty much depends on that and I'll look really stupid if there's some tiny difference in the moulding that makes it impossible...

*please correct me if I'm wrong on this, I can't see that mounting the transmission backwards makes any noticeable different to the dynamics, nor can I see any different in reversing the diffs