wtcc5s Novafox

[wtcc5 4227]

Got myself this beauty for a bargain. It won’t stay stock and not inexpensive for long. I plan to mix it with BBX parts to delete all its weaknesses and make it Fox-fast for the modern astroturf track. 
 

Right now I am impressed with how few parts this whole car is made of and how light and slim it is. Its parts barely fill the box it comes in.

 

Edit: Is the picture viewable for others? It doesn’t seem to load on my device…

[GToddC5 681]

Currently, the image is not loading here or linked.

[hamtaro 75]

Can't wait to see this.  What are you going to replace/upgrade in the fox?

[DPR250R 55]

Following. 

[wtcc5 4227]

@GToddC5: Thanks for the info. Tried it again. Should be there now.

Although there is not much to see at the moment as it is still nib.

@hamtaro: I plan to change the rear gearbox section to take advantage of the TA-06 oil filled geardiff and (as soon as it is available) can install a slipper. With a chassis design as ideal as this, I hope to find a simple and effective solution:

 

 The second approach will be the suspension. I want to have a wider stance for it to be easier to jump and take bumps. While working on that in front, I also want to find a look-performance-solution for the front damper. I think two dampers is the way, but don’t want to ruin that sleek line of this buggy.

 

[foz75 93]

I can see the pictures. looking forward to updates!

[hamtaro 75]

Here ya go, vintage French fox sudpension modifications

https://tamiyabase.com/articles/46-technical/178-vintage-fox-modification

 

 

[wtcc5 4227]

 

@hamtaro: This is gold 

[Baja500 93]

Nice! I use to do hop-ups modifying vintage rc, but if something broke, it wasn't easy and or costly to replace. Will be watching 👍

[wtcc5 4227]

I am back home 

I ordered the BBX early so that it was already waiting for me. The Novafox didn’t cause trouble at the customs, which makes me very happy. In the end it only cost me 105€ (compared to 180€ at Tamico). And I even managed to bring the box too.

So now the fun can begin!

[wtcc5 4227]

Couldn’t wait, and started with the key-unit for the Novafox that will come from the BBX… the gearbox:

This will get the geardiff from the TA-06:

 

For now I build it like I would for a RC10B6, with two gears and 5K oil:

 

 

Then I build the BBX gearbox. In hindsight buying the whole kit was the right decision, because Tamiya hides so much small shims on the parts-trees.

 

 

Unfortunately, the slipper is unavailable at the moment, so for now, I build it with the strange spur assembly:

 

 

The parts all fit together very nicely:

 

 

Except for the slightly warped dust cap, I am happy with this gearbox. It is a bit more complicated than needed, but we know that from Tamiya:

 

 

I installed the TZ motor as placeholder for now.

Next on, I will build the Novafox to see what this car is about and then to plan the integration of my ideas.

[ruebiracer 951]

Great project Kevin! Can´twait to see the end result. Fox is an icon,with a beautiful shape and unique look! The BBX gearbox looks quite universal and maybe a good design for some other projects! Thinking of Astute or Dynastorm. What is your opinion?

Kind regards,

Matthias

 

[wtcc5 4227]

@ruebiracer: It is definitely the most versatile gearbox for its flat bottom mounting points, the sealed geardiff and the available slipper. The only downside is the 8mm high floating motor. That kind of disqualifies it for real competition in my opinion. For the Fox it is great, because it had the motor higher also.

[Sgt.Speirs 1161]

5 hours ago, ruebiracer said:

The BBX gearbox looks quite universal and maybe a good design for some other projects! Thinking of Astute or Dynastorm. What is your opinion?

Kind regards,

Matthias

 

My recommendation for the Astute would be to use the King Cab TRF201 gear case😉

[Mrowka 474]

In my experience, the gearbox is the weak link on my Fox, so anything that beefs it up and adds a slipper is a good thing.

[wtcc5 4227]

I started the Novafox build yesterday. And like @Sgt.Speirs today said when we met: "Tamiya cars have a soul.", this car definitely has one. Already the first step makes this obvious with the monocoque design chassis:

The steering assembly is as simple as in any F103 chassis. What disturbs my freedom a bit, are the uneven long steering links. The servo saver also doesn't meet my standard and knowing the high-torque won't fit, I installed it to see where it collides. For now it fits with a bit of shimming for the lower front plate. The steering assembly is on my list.

 

The car definitely is a fast build:

 

The front suspension is the Boomerang-standard and consists of many tiny screws:

Unfortunately it has a lot of slop in the ballmounts and also comes with bumpsteer galore. The steering geometry is kind of off. Under full throw the inner wheel wobbles...

 

[ruebiracer 951]

4 hours ago, Sgt.Speirs said:

My recommendation for the Astute would be to use the King Cab TRF201 gear case😉

Of course, @Sgt.Speirs! I followed your fantastic build, you nailed it in my eyes! I was just thinking of other users / alternatives with even more potential for plug&play.... And I followed your Tamico cup battles in Leipheim at least in the net, which makes me wanting a Dyna Blaster now. It looked so cool, when you all let the Blasters fly!

[wtcc5 4227]

I continued with the rear:

Seems like I forgot to make pictures building the diff... It is a unique design, very simple with clever ideas and very slim, but outdated and it looks like it breaks easily.

The arms sit very tight in the rear and won't move on its own.

 

 

 Then it was time to attach the rear unit to the chassis:

 

The motor sticks out quite far 

[ThunderDragonCy 7285]

Really surprised this does not use hotshot arms and diff. 

[wtcc5 4227]

Indeed a unique and narrow design. Maybe they tried to reduce power-on-oversteer…

Final steps now for this pre-build. Tires and hexes or better call it circles were installed. I tried to install Super Astute tires… in front no problem. In the rear I learned that the later rims have a larger diameter, so I need to find other fitting tires from the Tamiya catalogue:

 

That concludes the pre-build. On the weekend I worked a bit with CAD to implement the BBX gearbox. I had a unavoidable collision with the rear mount of the upper monocoque and decided to replace it with a upper plate, that will also support the rear shocktower. For the mentioned I ordered Avante rear shocktower mounts. The lower gearbox plate will also be replaced by a longer plate, that will also replace the battery lid. Like that I reduce the complexity of the buggy further and now have the feeling, that this will become a wonderful racing fox:

A test print is produced as I write these words.

 

I also build the BBX dampers last night and find them very smooth and easy to build:

[wtcc5 4227]

Had a good evening trying the prototype designs:

 

The gearbox-shocktower-connector:

 

Lower chassis plate:

 

Gearbox installed:

 

Rear shocktower and Avante mounts:

 

Installed:

 

Rear arm mounts:

 

While I met the most difficult hole positions, I also made some silly mistakes having collisions with the gearbox housing and topdeck, as well as arms and lower chassis plate. Overall every part got a bit of change for production.

 

[wtcc5 4227]

I am having all kinds of mini problems with the rear at the moment...

I printed the rear arm extensions, but because the Fox arm is not really short, it is in the way of the extensions, so I had to go for a wide design near the hub mount:

 

A lower plate will connect the outer mounts with the arm.

 

Like that, I get a good width:

It is a bit close at the wheel and I don't like this design.

 

Next, I added the rear dampers. Here again a lot of fine tuning is needed to get all the distances right. As you can see, I am not there, yet:

 

Too much shims on the camber link, too. I can reduce it a bit in my next design, but because of the big spur Tamiya wanted for the BBX, I cannot do much here:

 

Once I get it all right it will be a nice car. Already like the look, even though I will still change a lot:

 

The last days, I worked a lot to optimize the rear layout. I will need to go all-in regarding the space and part design. For example: The rear arm mounts got a lot smaller to now fit 4mm closer to the centerline. This will allow the arms to move further in to have more space for a nicer extension geometry. Also the shocktower moved 10mm to the front to bring the damper more rearwards and allow big-bore-springs. The BBX rear springs are too stiff for my liking and this light car. In this process every part for the rear needed to be changed. I now fancy the use of Boomerang wheels and rear hubs to not get to wide in the rear. I bought golden Super Hot Shot wheels to keep the golden look 

 

[DPR250R 55]

In the article linked above it states that you can Boomerang rear lower arms.

Just another option to try. 

Really enjoying the progress. 

[wtcc5 4227]

@DPR250R: I really want to do that, but I want to use this car in the Tamico Offroad Cup. The rules are very open, but I have to use the original lower arms and the chassis. So an arms replacement is in this case not possible. Hence my struggle 

[wtcc5 4227]

With so many changes made, I want to make sure everything fits, so lets print:

 

A day later and the car is parts again:

 

The new arm mounts now are very close to the gearbox:

 

The new arm extension design:

 

... and then I forgot to make more pictures  The good news: the fitment is fine. The shocktower and the arm extensions will get another refinement.

During the build, I was wondering why the rear tires have no toe-in, even though I made the arms pointing forwards. The Novafox must suffer from understeer badly, because the hubs are toe-out. So I will switch them later. This will also result in less spacers for the camber-link... nice 

As I also worked on the body and wing, I can present teaser pictures of the look this car will have: