1/12 Scale MF01X Build (Porsche 934)

[naturbo2000]

I've had enough enquiries about my current projects, it's about time I kick out a build thread about my plans and current progress.
I'm loving building at 1/12 scale. My previous in this space was a Tamtech Gear Ferrari 288 GTO on a M08 chassis. For that I only had to take 5mm out of the short chassis length.

This time around I've picked up a Tamiya Tamtech Gear Porsche 934 Turbo RSR. Let's start with a motivation picture. Hopefully linking to tamiyausa is OK.

It's a lovely shell, but I have to say that the Tamtech Gear GT01 doesn't do it for me. I know it's not toy grade, but I prefer to do things a little differently. M chassis are generally close enough, or can be made to be

The Tamtech Gear 934 sits on a 190mm wheelbase chassis originally. I had two viable choices for hitting that short wheelbase on a M chassis, especially as I wanted the motor to be hanging out the back to match the 1:1 car:

1. M06 cutting 15mm out of the short chassis and chopping suspension arms around to get the rest. I figure it's not as hard as it sounds, but it would definitely require me to use a shorty battery (more on that later)
2. MF01X using the provided chassis spacers "out-of-spec" to get close to 190mm and chop the suspension arms around

Fortunately I had 2 planned builds this winter and I could likely build either on either chassis. I ordered both as chassis-in-a-bag kits from Tamico and set to work finding out what was possible. Overall, I had more confidence getting the MF01X down to 190mm so started there. The MF01X provides 3 spec lengths: 210mm, 225mm and 239mm by using a combination of spacers which make up the main chassis spine. Probably easiest if I provide some pictures from the manual.
 

Short uses B10/B11 ; Medium uses B10/B11+B3/B4 ; Long uses B10/B11+B8/B9.
But it's possible to go way off the beaten track to use other combinations and wheelbases. You'd need a custom centre driveshaft, but that's not as difficult as it sounds.
No spacers= 171mm wheelbase ; B3/B4=186mm ; B8/B9=200mm ; B10/B11=210mm ; B8/B9+B3/B4=215mm ; B10/B11+B3/B4=225mm ; B10/B11+B8/B9=239mm; B10/B11+B8/B9+B3/B4=254mm

186mm is close enough to the 190mm target that I chose to head there and build it back out. I know smarter people than me make their own 3D printed spacers, but I reckon I can do 4mm from trimming arms.
Let's have a beauty shot of the non-standard chassis buildup (and a sneaky peek of a modded arm).

And a shot of shaving the various edges of the arms and inserting spacers at the other end of the hinge to stretch the wheelbase out. blue+blue=4mm adjustment and we're done?

Not quite. And there's a really nice touch to follow that makes the choice of this chassis really neat for this project. I'm not sold on making a 4WD 934, so I could just not use the driveshaft. I may investigate a reversed one way diff in the front end, such that it's RWD under power and 4WD on the brakes. Probably not though.
We'll call that kicked off for now - but I am somewhat further progressed which I'll update soon. In the meantime, I'll kick the tyres on my other project with a 1/12 scale M06 Stadium Truck build thread.

[OoALEJOoO]

@naturbo2000 Very cool build!

Indeed, the flipped one-way in front gives you very good control with its 4WD braking. An alternative to the flipped front one-way is to remove the prop-shaft but keep the front diff. You can then stiffen or lock the front diff, giving it very good stability on cornering, while still being a RWD.

[ChrisRx718]

Interesting!

I need to complete my 1/10 934 MF-01X project, you can make up the correct wheelbase using purely Tamiya parts and fitting TL01 arms for the width. Project has stalled because I cheaped out and got Jazrider lower suspension arms and now it rattles like crazy. I need to replace those!

Following with interest 

[naturbo2000]

So the surprising but neat trick to this build came from a leftover I couldn't use on the 288 GTO. These Tamtech Gear cars are all about hiding the body posts. I'd got the mounting kit for the earlier build, but couldn't make it work. But as luck would have it. the kit does fit the front of the MF01X (and some of the other older M series - M05?).

So what follows is a bunch of photos to show you how.

For this build, with the low nose of the Porsche and the relatively high mount of the shocks, this needs to be mounted as high as possible. It really needs shimming with a wedge to raise it a little more, but I'll cope. The bodyshell will absolutely rub on the shock tower. I'll have to reinforce it so the paint doesn't rub through.

That front mount screws into the shell and is later covered by decals.

I imagine the next ask is "Show me the shell".

That's the best paint I've ever applied. A bunch of coats of Cobalt Green. A couple of coats of Core RC white knight followed by Core RC black on the inside and I think the rear edge of the spoiler. The Core RC paint definitely has more "texture". Rest of the Matt black is PS5 sprayed on the outside. Spoiler colour is the plastic as shipped. Needs some TS gloss clear for the green, but is good enough for now.

Of course you now want to see the shell on the car, so...

Rear is not attached, but I'm expecting I'll use magnetic mounts with the magnets glued to the gearbox and case. I reasonably happy with the wheels, but if anyone has any pointers to BBS mesh wheels in a M chassis size, I'd love to hear about it.

[naturbo2000]

You might note the rear is a good fit, but the front wheels are a bit wide. That's correct and the subject of a follow-up.

[Nikko85]

On 2/3/2024 at 12:24 AM, naturbo2000 said:

So the surprising but neat trick to this build came from a leftover I couldn't use on the 288 GTO. These Tamtech Gear cars are all about hiding the body posts. I'd got the mounting kit for the earlier build, but couldn't make it work. But as look would have it. the kit does fit the front of the MF01X (and some of the other older M series - M05?).

So what follows is a bunch of photos to show you how.

For this build, with the low nose of the Porsche and the relatively high mount of the shocks, this needs to be mounted as high as possible. It really needs shimming with a wedge to raise it a little more, but I'll cope. The bodyshell will absolutely rub on the shock tower. I'll have to reinforce it so the paint doesn't rub through.

That front mount screws into the shell and is later covered by decals.

I imagine the next ask is "Show me the shell".

That's the best paint I've ever applied. A bunch of coats of Cobalt Green. A couple of coats of Core RC white knight followed by Core RC black on the inside and I think the rear edge of the spoiler. The Core RC paint definitely has more "texture". Rest of the Matt black is PS5 sprayed on the outside. Spoiler colour is the plastic as shipped. Needs some TS gloss clear for the green, but is good enough for now.

Of course you now want to see the shell on the car, so...

Rear is not attached, but I'm expecting I'll use magnetic mounts with the magnets glued to the gearbox and case. I reasonably happy with the wheels, but if anyone has any pointers to BBS mesh wheels in a M chassis size, I'd love to hear about it.

This looks stunning. I love custom sized MF01x projects.

 

[delta.triangle]

Great work so far @naturbo2000,

Glad to be one of the people that was bugging to see progress on this. I'll be following closely as I've got all the body parts for the Tamtech Porsche 934 Turbo RSR (plus a can of Cobalt Green) and have had a hard time finding a GT-01 Chassis these days. In my case I would almost be inclined to go 4WD.. Let's see how you get on with the MF-01X

[naturbo2000]

I've since chopped down the battery holders. A regular stick LiPo will not fit across the body so I'm making modifications to hold a shorty. No photos of that just yet. It's quite messy .

Instead I'll post something about narrowing the front track. An overhead shot shows how bad the front track is beforehand. I've swapping the hexes out from original 6mm to alloy 4mm hexes, which is about as good as I'll get for this project. Doing so has required getting the dremel out to sand down the inside of the wheels to match (otherwise the wheel centres rub on the hubs).

Original (!)

You don't need a picture of hexes, but the hack job for inside the wheels may be useful. Front wheels are on the right. Dremel disc would only just fit in M-Chassis wheels. I don't think I fatally weakened them (!).

Net effect can be seen in the following picture. The width reduction can be seen as the extra axle protruding.

 

For those of you following along, I've also started on decals. It's a really beautiful shell and scheme. I'll likely upload similar to the gallery when complete. You might notice I'm currently missing a centre driveshaft. I'm waiting on a parts order for an alloy one to cut down. I'll hopefully have the solution for the rear body posts arrive sometime this week too.

 

 

[naturbo2000]

Today was about getting the rear body mounts sorted. It was pretty clear I couldn't re-use the Tamtech Gear hidden mount. Quite simply far too much motor and gearbox in the way. I could use the regular MF01X body posts mounted "backwards" and have the posts come out of the roof, but I wanted to try something neater. Magnets are the obvious choice (and I might go to them after I've tried today's solution out. I'm hoping that having hidden body pins on the front might allow me some flexibility in solution, given I've seen how little "just" magnets are any good.

I'm a cheapskate and figured I'd see what these older Stealth Mounts are like to begin with. Apologies for the tablecloth. Awesome as it is, it doesn't help you identify any of the individual pieces involved. Basically it amounts to a body-mounted balljoint and clip and a bodypost-mounted arm for it to clip to. I'll be more obvious when you see photos. Less strong than magnets. Maybe strong enough. Instructions are all in Japanese, but it's easy enough to follow the drawings.

Anyway I picked up some TL01 mounts as I figured they gave me more options. This is what I'd planned for them:

And then magnets or clips mounted off them. Unfortunately there simply isn't enough room. and those mounts are really designed for vertical posts. So I had to have vertical posts. Really, really short vertical posts.

Yep - that's as tall as they can be and still fit under the back window! Fortunately they are still tall enough. The Stealth Mounts assemble as follows:

The vertical hole sits over the body post and has a screw to secure. On they go, basically as low as possible. Here they are with the body balljoint+clip removed.

Clip the balljoint and clip back one. Double-check fitment. Apply the sticky pad and put the body onto the chassis. Tada.

Oh - why couldn't the sticky pads be black? And why didn't I just pull some black double-sided tape from my race stash? I should probably fix it sooner rather than later. Either that or I'll run some black vinyl like a rear sunscreen strip or something.

A pic of the clips left attached to the body when the body is removed from the chassis.

And a few pics of the end result. Electronics but no battery installed. It rests a little lower than these pics show.

That last pic suggests I've got some bumper rubber tidy up to do. (It's paint, not decals). More decals work to follow.

[naturbo2000]

Black pads FTW

A few more decals applied. Just the awkward amber ones on the front end to go. I wish I'd masked and painted that bit...

[naturbo2000]

Finished the decals.

Remaining to-do:

• Paint and fit wingmirrors
• Trim down the centre driveshaft (I have a blue alloy one to make the job as easy as possible).
• Finish the battery holders
• Light buckets and LEDs
• Think about that reverse front one-way
• Run it until the wheels fall off