Juhunio's Bits-A-Builds

[Juhunio 6830]

Then onto the rear suspension shafts and arms. It's a neat arrangement, with the shafts threading through the arms and into plastic blocks which are screwed into the bottom of the gearbox

You don't get the flexibility of other variants of this arrangement, where the blocks are screwed onto the chassis and you can change toe angles by changing the blocks around, but it's a cool set up nonetheless. As is the kit standard aluminium motor mount / heat sink

It will be good to see how this works with the aluminium blocks in the bits-a-build, if I can ever find the rear blocks . Also noted that these shafts could be upgraded to 3x48.5mm titanium coated shafts (54388) in that build 

[Juhunio 6830]

Rear upper arms use kit standard turnbuckles….add in the full ball bearings throughout and CVA dampers as standard and the SS was clearly a pretty high standard kit in its day. 

The original turnbuckles are a little bit scratched but nothing too drastic, so time to get the calipers out to measure the precise 9.5mm gap required between the adjusters 

The turnbuckle and adjuster wrenches are up there with the damper pliers as the best Tamiya tools, they really save your thumbs!

Add in the rear dogbones, uprights and axles and that’s the rear gearbox done ✅ 

The uprights are attached with 3mm shafts secured by an e-clip at each end, rather than drilling a grub screw through the upright into a flat recess in the centre of the rod which allows for the shafts to sit flush inside the upright rather that stick out either end 

EDIT>>>>>>

Turns out I couldn't live with the scratched turnbuckles after all, and had a couple of 23mm blue aluminium turnbuckles loose in the parts box so....seeing as how this is having blue ball connectors, and these turnbuckles are for the rear end where the aluminium is less of a risk....

[Juhunio 6830]

A new (old) carbon reinforced chassis arrived today 

[Tizer 606]

Are you going to keep it a tub chassis or go carbon? Both would be best haha! 

[Juhunio 6830]

1 hour ago, Tizer said:

Are you going to keep it a tub chassis or go carbon? Both would be best haha! 

I'm going to keep the tub chassis but add carbon / SSG damper mounts, upper deck and battery holders 

[Tizer 606]

4 hours ago, Juhunio said:

I'm going to keep the tub chassis but add carbon / SSG damper mounts, upper deck and battery holders 

Cool! Same as one of mine. I'm going for the reinforced tub with SSG upper, shocktowers and batteryholders + most of the silver upgrades. I think the tub adds character It's how it was originally designed and if I want carbon I'm better off with my TRF414's.

[Juhunio 6830]

The weather forecast is looking decent-ish for the next week or so, and as I lost the entire summer painting season through being away I've decided to catch up a bit! Building can be done throughout the long winter months, but the painting window is drawing to a close 

So time to crack out the bodywork tools and prepare the TT and AMG shells 

[Juhunio 6830]

Really pleased with how both shells trimmed and finished up, but masking the TT front and rear sections goes down as categorically "not fun" 

[Juhunio 6830]

The masking may not have been fun, but at least it was worth it . Phew!!!

[Juhunio 6830]

The TT shell now has the wing added. It's a pretty mad looking thing...

 

Jeez, getting those 2mm screws and nuts lined up and biting when working inside a tight recessed space is a test for the patience, blood pressure and ageing eyesight 

 

Keeping everything crossed that the repro Red Bull stickers from MCI are sound when they arrive...kind of gone past the point of no return now 

[Juhunio 6830]

A couple more choice parts for the 04SRTRF bits-a-build arrived today. Particularly delighted with the rear suspension blocks!

Those aluminium centre pulleys...the examples I've seen were based on using one of them in combination with a front or centre one-way, but I've no plans to use either. I took a punt on being able to use two of the aluminium centre pulleys to replace the standard plastic pulley (50878, which I couldn't find anywhere) and pulley stopper 

So I did a test build and it works! The hard centre shaft has two recesses to receive the grub screws that hold the pulleys in place....

So that will make for a pretty beautiful spur-and-pulley assembly come build-time 

 

 

[Juhunio 6830]

The TT Red Bull stickers from MCI turned up today, looks like Nathaneal has done a great job as usual. These were put together on request and the dimensions are spot on, so I'm really grateful 

[Juhunio 6830]

The two pulleys are cut with a squared-off centre to fit onto the similarly-shaped pulley stopper, which is then fixed to the centre shaft via a grub screw which sits in a recess on the shaft to create a fixed axle

Getting the spur assembly and pulley assembly to all line up and thread through the bearings in the gearbox sides while ensuring the grub screw is over the recess and facing you so you can screw it down was pretty fiddly 

[Juhunio 6830]

A few new arrivals for the 04SRTRF today. Hex head screws and 840 bearings, plus this racing stabiliser set

It's a pretty cool set, as not only does it contain a full set of lower arms and front stabilisers, the stabilisers attach to the upper deck rather than around the front of the gearbox. Bit different to the usual set up, and further blue aluminium and carbon fibre parts, so I thought it was worth a look 

[Tizer 606]

Never knew that was sold as a complete set with the mounts, brace and arms together. Need to keep an eye out for another, that's cool.

[Juhunio 6830]

Building the front gearbox and suspension, the only oddity was the instruction to put a black o-ring AND a urethane bushing inside the outdrive. The drive shaft is pretty short, it doesn't take much for it to pop out of the axle but this felt like too much padding and caused the suspension to be very stiff, unable to return to rest from a raised position. 

So I cut the bushing in half and just used half each side with the o-ring, which seemed to help the drive shaft stay inside the axle whilst freeing up the suspension. We'll see how it all works once there is steering and dampers in place

Other than that, only thing worth noting is that it was a bit of a tight fit for the upper arm to fit onto the ball connector on the back of the damper stay....initially I assumed I'd made a mistake and put the connector in the wrong place, but no it's just a tight fit in that recess

The front and rear gearboxes now happily mounted onto the chassis, along with the kit-standard metal steering posts

[Juhunio 6830]

On 9/9/2021 at 9:10 AM, Juhunio said:

Yup, I've got the K2 (tensioner) and K5 (steering bushing) parts, they were unused on the SS and the original parts trees and leftovers came with the kit

I thought I might get away with not needing a new K tree at all (with the hop up damper mounts, steering assembly and hubs) but seems like I need those two little K11s for the belt tensioner assembly. Gah! 

Hmmm, maybe not....

Rebuilding the steering this morning and one of the arms (K3) had a crack in it 

So I did need that K Parts tree after all

Mmmmm, steering sat on bearings. Smoooooooooooooth 

All mounted on the metal steering posts and tie-rods connected. Decided to use blue aluminium ball connectors throughout, it's not going to get any real upgrades so a wee bit of bling will do no harm

And on with the upper deck. All those self tapping screws found their original threads nicely 

[Juhunio 6830]

I bit the bullet and ordered a C Bag from Tony. It seemed to be the only way to get that 4.5x7.4mm flanged tube for the 04SRTRF, and seeing as I'll also need the mount screws, cap screws, tension post, washers, e-rings and bearings for that build too....

The damper bits and bobs and the pinion will all go into the SS, replacing the missing pinion and the TRF dampers that came on it which I'm moving over to the 04SRTRF. 

The adjusters, tape, fasteners, turnbuckles, clips and nuts will get used somewhere, at some point 

The brass connectors and tapping screws....not so much 

[Juhunio 6830]

So next step is the damper build, always one of my favourite processes. The hardware comes from the newly purchased C Bag, the plastic parts left over from something that benefitted from an upgrade to TRF dampers

Also an opportunity to break out the damper pliers, one of my favourite tools 

Lots of spacers needed on the piston rods

One big difference between these kit dampers and the TRF sets is the pistons. Rather than pre-formed circular pistons (TRF), these are cut off the parts trees so there is often a tiny flat spot on one part of the circle which lets little air bubbles in as you move the piston up and down, and with all those spacers there was a large air trap under the piston too, so it took a few goes at topping up, moving the piston, topping up some more, moving the piston, topping up some more....

After all that excitement, time for a little rest! To let all those last little air bubbles out...

[Juhunio 6830]

With the the dampers on I couldn't resist skipping the electronics install and attaching the wheels and body posts so I could do a test body fit.

One obvious upgrade is a set of 6mm clamp hex hubs to replace the plastic pin hubs. Just feels right! The rear axles comfortably took a 1mm spacer to help the wheels fill the rear arches, but it's looking good 

[Juhunio 6830]

A pretty standard set of electronics....

The 'Genuine Tamiya' silver can came in another kit and never got used. This seems like a good place for it, paired with a TBLE-02S. 

There was no servo saver in the kit so I've used a hi-torque set on an Etronix metal geared low profile servo which I've used before and performs well

First, in with the motor and pinion, which meshed together nicely and passed the piece-of-paper test

[Juhunio 6830]

Keen to complete the SS chassis build and crack on with the 04SRTRF bits-a-build , I skipped on to the final pages of the manual and built the front and rear belt runners 

The front tension pulley is a pretty cool thing; two 730 bearings slide onto the tension post, held together by two plastic caps and secured by an e-ring. The belt runs against the bearings, while the other end of the post slides through the plastic adjuster to be secured by a lock nut.

If you loosen the lock nut the tension post slides up and down to adjust the position of the bearings on the belt, increasing or decreasing the tension. Neat!

The rear belt runner is a more straightforward affair, another 730 bearing running against that 4.5x7.4mm flanged tub from the C bag, all screwed into the chassis using a 3x18mm tapping screw. There were no 18mm screws when I disassembled the chassis, the original owner must have just used a 15mm screw. So the new C Bag came in handy again 

And both in place. Both belts are as good as new and the front belt seems to be tense enough with no droop anywhere, so I've left the tension pulley in its loosest position where the belt runs on the bearings but they're not applying any significant tension

[Juhunio 6830]

Oooh, nice couple of deliveries today bringing (I think) the final pieces I’ll need for the 04SRTRF, including the 2nd aluminium ball diff pulley 💥 💥 

 

Pretty sure that step-tapping screw that goes in the bottom of the gearbox is the only tapping screw I’ll use, everything else will be replaced by hex-head machine screws 😎

[Juhunio 6830]

POETS day today, so gave myself a couple of hours this afternoon for the final few details on the SS chassis build

First, you have to cut the foam bumper to fit under the TT shell. Not a great job, not a bad job, it fits nicely but is a little scruffy. I used a very sharp craft knife so not sure how I could have made it much tidier, but it will be hidden by the shell anyways

And then to solve the problem of the antenna mount. Like other 'older' chassis kits I've built, the antenna holder is placed way out back, too far away from where the receiver is placed for the antenna cable to reach. I assume the newer 2.4ghz antennas are much shorter than whatever tech was around when these kits were new, and the antenna holder placement is no longer appropriate

So I borrowed a trick from my TB-02R and ordered a separate antenna holder that I could screw into the top deck

It meant removing the top deck so I could thread the screw through it from underneath and attach the antenna holder above, but no great drama and it worked a treat

[Juhunio 6830]

So that's the TA-04SS chassis recondition rebuild complete! Pretty much kit stock, apart from:

• hi torque servo saver
• blue aluminium ball connectors
• blue aluminium rear upper arms
• clamp-style aluminium hex hubs
• blue aluminium wheel nuts
• altered antenna mount position

It was a really lovely kit to build, despite all the self tapping screws. It feels like it should be a good performer, and in the quick carpet test I did to check the electrics were all set up right it was quick to respond and whisper quiet 

One last hole reamed through the roof for the antenna tube, and that's the body finished and ready for stickering. I'm going to save that for a rainy day...

Now it's time to start on the 04SRTRF