Shergar’s TRX-4

[Shergar]

About a year ago I almost bought a proper Crawler, but then reason dawned and I thought I’d buy a cheap truck to see if I even liked crawling and trailing. That was a Maverick Scout, which gained a dusty old stock Radshape chassis and mutated into the FrankenScout It gave me an idea what I wanted, and how I might use an RC. It just needed to be lighter, more agile and without the dreaded torque twist. I also learnt not all tyres are equal, not all diameter tyres are equal either. So it gave me a blueprint of what might work. I also knew I wanted to build it. The SSD Trailfinder and the Gmade Buffalo were strong contenders, how ever I keep everything for ever and stick to the “buy the best of the obvious” In 10 years time TRX-4 bits will be everywhere still, Gmade maybe and the Trailfinder no chance, I’d be cobbling bits of SCX10 to it to keep it alive. So after much deliberation I picked the simplest TRX on locked diffs. Then ordered loads of trinkets for it 🤣

What’s in the tightly packed box!

 

More to come as more parts arrive - Hobbywing 1080 and Holmes Hobbies Trailmaster are here already, but I will start the build when everything else ordered turns up. I’m still on the fence about the tyres because I’ve found the stock Canyon ones very good, but I want BF Goodrich written on my sidewalls 🤭 and the bodyshell - pictured below - I just cant get over the fact it doesn’t have a “marque” badge on it, and of course hard body temptation rears its head….  except last week I counted I rolled the FrankenScout 5 times in an hour so Lexan (and reason) is likely to triumph!
 

As the internet tells you, its true - the shell is much better proportioned in the flesh. However if you don’t want the boat anchor accessorises you are left with lots off holes! Traxxas could leave them unpunched on the builders kit couldn’t they?

 

Further ramblings to follow!

 

[tomr]

Have you started it yet?  When ya gunna start it?  Will you start it tomorrow? 🤣

 

Got yourself a nice kit I’m looking  forward to seeing it all come together 👍 

 

[Lone-wolf]

Interesting about the punched holes in the shell, that is a no go for me, would really rattle my mild OCD

[supersavage]

The stock body and the accessories really grew on me on the body is painted and it's all together and I think you'll be quite surprised once it's done. Though it really does benefit from having lights fitted to it.

 

If you're still not sure on it check out The Scale Builders Guild and Harley Designs on YouTube as they did a budget build off with the TRX4 Sport kit and did some interesting things with the cage on the back.

 

I'll also post a couple of pics here to tempt you to hurry up and get it built 😛😁

 

 

[Shergar]

Cheers for the encouragement, your build was one of my reference points 👍

 

I have watched both series of videos, SBG is how to do YouTube, Harley is how to hover over fast forward….. that Exocaged guy is good though, I like him and he has some TRX4 videos that are worth a watch.

 

Maybe I will spend my bodyshell funds on some fancy beadlock’s then!

[Stormbringer]

Does your kit have portals ?

If it does Amazon do brass portal covers for not bad prices plus theres a lot of bits/pieces on Amazon as well 

[Stormbringer]

@supersavage is that the traxxas light kit fitted to yours ?

[supersavage]

8 hours ago, Stormbringer said:

@supersavage is that the traxxas light kit fitted to yours ?

 

Yes.

[Stormbringer]

It looks good mate 

[Shergar]

Slowly building the parts pile up, BIL printed me this nice little tray, heads up to the creator for designing it:

 

https://www.thingiverse.com/thing:3681466

 

 

Its grey to match the chassis plastics, it’s not just what he had in the printer 🤣

[Shergar]

Finally started building the TRX-4 😁

 

Made a start on the wheels…. I’m keeping the Canyon trails and the foams they came with (which foamwise might bite me in the backside - who knows) and the ugly but incredibly tuff plastic rims now live in the spares draw. Instead I’m trying these unashamedly IP ripped off Injora beadlocks.
 

Open up the foam lined box and there pretty good, bar a few tiny nicks and quite sharp edged centre ring that I gently deburred, but the paint finish is good and the screws nipped up nicely. At about £35 delivered you really cant argue. I did however use red not blue threadlock so they will come apart again, just in case, or more likely because I’ve decided to change the foams.

 

Very eagle eyed might have spotted I did blast the black beadlock rings with Tamiya flat clear acrylic, to take the gloss off them. Being strange I then sealed the lot with Autoglym  extra gloss protection sealant - previous experience has shown that wheels rinse off much easier, but these really have a nice depth of alloy shine to them, yeah I know loopy 🤣

 

Anyway heres how they ended up - 3 more to do now…..

 

 

 

[Lone-wolf]

looking good mate

[Stormbringer]

Very nice mate 

But we find the blue threadlock more than enough and never lostt a wheel screw yet touch wood

Edited May 4, 2022 by Stormbringer

[Shergar]

I normally use blue loctite myself, but im using the red Tamiya truck gel because I might want to split these 👍

[Shergar]

So you may be aware from this thread I purchased the cheapest TRX4 sport kit - the one with fixed spool differentials and a single speed gearbox - because thats the specification I wanted, well nearly wanted. The truth is I actually wanted the high low ratio gearbox, so after a recommendation on here I ordered one from Jennys in the US to drop in it (quite cheaply too, cheaper than buying the conversion kit all shipped). Now below you can barley tell the difference between this bag of bits and the assembled beauty. 
 

https://jennysrc.com/collections/trx-4-defender/products/copy-of-trx-4-tactical-unit-transmission-spur-slipper-clutch-linkage-traxxas-82066-4?variant=7065300926518

 

 

Now the 2 speed was an unused (but brand new)  RTR take off part and was pretty smooth free running. So obvioulsy I cracked it open to mess with it needlessly 😁 It did come with the 45 tooth spur though so I ordered a 9T motor pinion to drop the gearing as low as I could. If you want to know more, Harley has a very good video 👍

 

 

 

What you would find inside, ample grease and very fine tolerances, though don’t lose those shims when you pry it about. Now because I implicitly trust the internet, rumours persist some of the smaller rubber shielded bearings run free-er with the shields off, but going one better for about £3 I replaced all 3 dinky 5x8x2.5 bearings with new unshielded ones from RCbearings. This decision I might learn to regret if I go swamping with it (flip side If I kill the bearings with fluid, I’ve probably rinsed all the grease out the gearbox too, so its still knackered). The rest I squeezed some machine oil in on both sides of the rubber shielding just incase anything was dry.
 

Everything got reassembled with fancy blue Vanquish grease (it seems nice, tacky rather than greasy, it might be crap!) with a little smeared round the seals of the 3 main pieces and finished off with stainless fixings. No grease on the shifter, I left that dry but did add the tiniest littlest dab of silicon on the chrome pin/rubber gasket interface.

 

 

Next I intended to build my caveman differential-less axle next, however this seemed disturbing:

 

 

Like I said this is intended to be my nice swamp avoiding rig (sure it will get wet but I don’t intend to submerge it) however I thought I could do better than a rubber plug and an evil E clip to plug the hole for where the diff lock cable would route. Part of me thinks in the end the E clip will slice the rubber and release the bung backwards into the axle casing. So I rummaged for the instant gasket and plugged the holes, pumping in from the inside (you get quite a deep seal). Tomorrow I find out if its good enough to stay put, if not the heath robinson plug goes in when the axles are bodged, sorry built.

 

 

 

 

Edited May 6, 2022 by Shergar

[Kpowell911]

Jennys are absolutely brilliant arent they?!

[Shergar]

2 hours ago, Kpowell911 said:

Jennys are absolutely brilliant arent they?!

They really are excellent, quick too! I appreciate you giving me the tip off 👍

[supersavage]

I haven't had any problems with the E clip bungs yet other than being a bit fiddly. I'll have to check out Jennys as part of me still wants to put a front Unlocking/locking diff in mine.

[Shergar]

So I finally got back to the box of TRX-4 bits!

This step is the front and rear locked axles (also referred as spool) and an underdrive for the rear axle. This should give a 13% overdrive even though I’m using the stock front differential - ratio 3.09:1, with the accessory rear ratio of 3.5:1 . For the gearbox I’m using a 45/9 transmission ratio, I don’t think I can gear much lower. Just as well I like it slow!
 

Really not keen on red diff covers, but I’m too tight to buy two so only the rear is getting a black one on! What you get in the kit:

 

 

The difference in the gears, spool the same, underdrive on the left kit gears on the right.

 

 

I have chose SSD portal weights on the front that are really nicely made, if a little sharp in places. Minus cheapskate points for SSD not including the two front screws only those on the back. I upgraded all other screws to stainless and as mentioned and trying Vanquish grease on the gears, its seems quite free spinning, hopefully it is.

 

The other thing I’m trying is a C.L.P. oil - Cleans Lubricates Penetrates. Intended for guns lets see if it works on CVD driveshafts!

 

 

Finally the completed axles 👍

 

 

 

 

Edited May 30, 2022 by Shergar

[Stormbringer]

Good progress mate 

[Shergar]

Should be finished by 2023 🤣 

[Stormbringer]

Wow that quick 

[Shergar]

Chassis done!  All standard… except the 3D print 1080 holder, the Bowhouse LCG tray, the alloy Yeah racing servo mount, Bronco arches with clip fittings and 2 speed gearbox. But except for that all standard 🤣

 

 

I will add these pictures of the Bowhouse tray, note the different rear chassis brace which is pretty sturdy.  I have put 3mm shock spacers under the tray mounts so I could run my cables underneath without crushing.
 

Downsides - Hobbywing 1080 is a bit tight on receiver lead if you use the standard receiver box - I put an extension servo lead inside rather than have it taught. Also the standard Traxxas grub with the 9 tooth pinon is proud (of the teeth)and extremely close to the spur, so I  did slide the pinon further out (off centre of the spur) just incase. The motor mount is an alloy one but both this and the factory one still wobbled the top of the spur housing, will keep an eye on both those things. Reading forums its seems quite common however. I may swap the pinon out after a test trail for a larger one yet.

 

Other thoughts? I will say its bloody heavy - It is built like a 70’s Mercedes and weighs the same too! Front rear balance  - with a shorty battery it tips forward, with a regular battery it still tips forward too.

 

 

[Stormbringer]

Coming along nicely 

You think its heavy just now wait till you brass it up 

[Shergar]

BEHOLD IT LOOKS LIKE A TRUCK!

 

 

Well it will when I assemble the propshafts 😂

 

I’m surprised at just how supple it is, there really isn’t a lot of drag in the drivetrain for all those  gears in the portals, but like I said no propshafts yet! The Traxxas shocks are nice, but not the miracle I expected mind - a Tamiya CVA is just as good. I’m using the mystery Traxxas shock oil, though it seems very soft - I might go harder in the future. Any idea what weight it is?
 

The Bowhouse tray bottoms out on the rear links, but should be alright for my use - its not getting bashed and landed from 10 foot. Yet. No idea how I’m mounting the Bronco clip frames to the body - I might bolt straight to the shell with some foam washers in the middle.

 

 

 

 

I’m over the moon with the VanquishVS4-10  front bumper and the GRC servo protector, both very good value and accidentally fit each other like a glove! Excellent approach angle too and clears easily on full lock.

 

 

 

The rear bumper looks like it might stick out and act like a hook, so maybe the hacksaw will come into play once in use.