Another Marui project - Ninja/Shogun

[silvertriple]

Hello,

Few weeks back, the postman delivered 3 parcels, among which there was two Marui rare cars: a Ninja, and a Shogun (from two different origins). It is quite exceptional get a Shogun, but to get a Shogun and a Ninja the same day is probably even more nowadays... Specially considering that there was also a Samurai in very nice shape in the last parcel of that day...


The Ninja chassis is in good shape, with its bumper and all the elements that comes with it. The body shell will require a replacement. And I have already some multipurpose driver figures from The Optima House to complete it so its good.
The rear transmission seemed to be locked but upon inspection, it seems that there was an mistake made to rebuilt it and a long screws on the shaft cover instead of a short one was the cause of this. This is sorted. I will still need to do a full tear off to clean it up, but beside that, it looks fine.

For the Shogun, the situation is more difficult:
- the rear gearbox will require some work.
- Front gearbox is missing the D-Cut bevel gear which transmit the power from the rear, the central shaft and the joints
- for the wheels, 3 rims are broken (they are extremely rare, probably even more than Samurai ones)
- Driver is missing (but same as for the Ninja, I will have an easy solution). Bumper is missing (it is the same as the Ninja but the color is different), and the battery door is missing as well (as often on those Marui chassis).

I had already a solution for the central shaft and joints.

I'll probably have to model the d-cut bevel gear to complete this.

I did not tear the Shogun yet, but worst case scenario, I have already some small metal bevel gears ready just in case (I had an opportunity to get those, and since I would like to have a Coors as well at some point, that could be useful). Further, if my understanding is correct, the Samurai rear diff is the same as both front and rear diffs used in Ninja/Shogun (and that means the spare diff set from Aristcraft I have could be used as well, but I will have to specifically confirm this in situ).

Yesterday, I decided to get into the operations. And I decided to focus first on the battery door.


It is a simple part. I took the measures and did it in Fusion 360. 15 minutes later, I had this.


And this morning, I test printed my door... Not bad, a quarter of millimeter to review on the locks and that's it (I believe it could work that way, but as it is already difficult to get the battery door out, it's not what I call perfect so I corrected it).



Then, putting all the pictures together in my files (like I do always with my RC cars projects, for which every pictures you see on a thread is before stored in a folder for the pictures of the project, next to the documentation and so on), I discovered there was two version of the battery door. Here is the picture I received from a friend with a Marui T-Bird Coors. There is some ribs added at the rear end, likely to protect the gearbox.

For the small story, I had some discussions recently with a friend with another T-Bird Coors, and that one don't have the ribs. I did further search on internet, and found some pictures with Shogun with the battery door with the ribs... My assumption is that those ribs were added at the time of the introduction of the Shogun (and there was a few months of T-Bord Coors production without them - T-Bird released in August 1987, and Shogun released in December 1987).

I decided to rework my Battery door design to add ribs (it definitely makes sense to protect the gearbox): I do not have precises measurements for the ribs, so I made them up from the thickness (I had a picture from my friend with the Coors indicating this), proportion and lining up elements with other elements, and the size of the gearbox part it is supposed to protect...


I did the design with MJF/SLS PA12 printing in mind, so it had to respect some thickness rules to be printed anywhere... I'll share the parts on my thingiverse at some point when I will have the final part printed. And while I did start this project officially, that doesn't mean it will run quickly like the others that are on top of the priority list, so don't expect this one to move fast

Thanks

[silvertriple]

Another part modeled... The bumper


I may want to print the side that attach to the chassis to check my measurements, but they are normally pretty much straight forward to measure, so little level of risk.

[Dadio]

Not the greatest looking designed bumper , not your fault but if it were for my personal use I'd design something more angled up at the front .

[silvertriple]

Not the greatest looking designed bumper , not your fault but if it were for my personal use I'd design something more angled up at the front .

The fact is the bumper is actually on two parts... This is the top part. It is fixed on the small bumper, which is already angled up. and it is also placed quite high. I will model further parts (I will need to do it, as I believe it is required to model the gearbox properly in order to model the gears inside (specially the bevel gears)). Once everything is done, I may work out some alternative bumpers anyway...

[silvertriple]

One parcel which I was waiting for some time arrived today from Sweden... It took much longer than usual, and the tracking of the parcel still show it under transportation in France at Sweden side and under preparation at sender on French tracking side... I had some fear each time I opened the tracking. My wife did receive the package today and she did not told me, so I was surprised to find it when back form the office...

It was within a bigger box, but inside there was a nice box


And inside the box, an incomplete car (missing wheels and central shaft, and maybe other details). And there was a lot of goodies, which should allow me to complete 3 cars (at the exception of the wheels).


The plan was for this Coors to be a donor chassis for the Shogun. I'll probably missing wheels set and a rear gearbox for the Coors, but now that I have a box, we can say that I have an incomplete Coors to complete

[silvertriple]

I've ordered a Nylon grey MJF gearbox from OptimaHouse and some pinion covers. That should allow to complete the Shogun chassis.
For the off road wheels, I believe I have solutions for both Shogun and Coors.
For the on road wheels, I'll need to find some foam tires and adapt wheels (not much issue, in fact, I just need to find proper tires)
Last issue : propeller shaft. I have 2 and 3 chassis. Looking at potential alternatives, the Boomerang re-re propeller shaft may do the trick. If someone can give me the exact length, it would help

[silvertriple]

Just a quick precision, the propeller shaft characteristics are the following :
- wire 2mm based
- length 177mm
- ends are 8mm wide

At the end, the Tamiya TA01/DF01 seems to be very close from this (about 175-176mm). I've ordered one, we'll see once it arrives.

[McAnic]

Just a quick precision, the propeller shaft characteristics are the following :
- wire 2mm based
- length 177mm
- ends are 8mm wide

At the end, the Tamiya TA01/DF01 seems to be very close from this (about 175-176mm). I've ordered one, we'll see once it arrives.

Following. Thanks for sharing this information. I was looking for an alternative for a propeller shaft and I did notice the Marui is longer. I might be mistaken but assumed the TA01 is about 170mm. Did you receive the propeller shaft yet? And did it work? Thanks.

[silvertriple]

Following. Thanks for sharing this information. I was looking for an alternative for a propeller shaft and I did notice the Marui is longer. I might be mistaken but assumed the TA01 is about 170mm. Did you receive the propeller shaft yet? And did it work? Thanks.

Thanks for the reminder!
Received the shaft on Wednesday, I took pictures, but I was a bit busy working on the Nichimo CAD work to think about reporting it.

There is about 3mm length difference, and the shaft is not as wide as the Marui (this is a detail).


Had a quick check with one of the chassis (Coors, as the Shogun and Ninja are in a box under other boxes)


I believe it is too short. Two options I can think of from there:
1. I would consider cutting it, work out a D-cut at each end, and create a sleeve which would allow to lock the shaft end at the right length with some set screws..
2. use a 2mm wire and bend it to the right dimensions...

[Dadio]

Having raced a Hotshot back in the day I've thought about the wire prop shafts , the main issue is only if you intend to run it , when running they tend to flex into an arc between gearboxes and cause a big vibration , my original racer had a much more substantial probably 3mm stainless steel shaft made by TMS to cure this , this also opens up the possibility of a one way roller bearing on the shaft and maybe a central support bearing , none of this is worth doing for an occasional light runner but STILL fun to do , it's on my list for my Hotshot .

[McAnic]

I believe it is too short. Two options I can think of from there:
1. I would consider cutting it, work out a D-cut at each end, and create a sleeve which would allow to lock the shaft end at the right length with some set screws..
2. use a 2mm wire and bend it to the right dimensions...

Thanks for checking. Too bad it’s so close. Probably will have to bend a wire then.

[silvertriple]

It maybe time for me to start the active part of this project.

Except stickers, I have everything to be able to tackle the Ninja.

I ordered a bunch of modified pilots from Optima House : they have been modified specially for me so it won't require any additional work to make the vent holes on the front (that was painfull when I did the Samurai). And when I say a bunch, I have around 20 of them. The 3 parts pilot will be easy to paint, and with the vent holes it should help to have this nice driver standing out (and yes, I intend to put it in many more cars, and the different possibilities of fixation make this quite easy . Anyway, I picked up 2 of the box I received, and they will be for the Ninja and the Shogun, and I'll probably get 2 additional ones for the Samurais, so I can paint them all together...


I won't do my driver box art like. I do like to make different helmets at least. I have some ideas with those, and it will rely on some masking... And for sure the 3 parts head will make my life easier...

As for the wheels and tires, I hope to find some nice original foam wheels set for the Coors. For the off road tires, the problem is not that complex : the Ninja has a proper set of tires, and for the Shogun (and as well Coors offroad), there is some of the Tamiya tires which looks like the original Marui tires so that will do it, but since they are 2inches, I'll have review the wheels size to accomodate with this.

For the on-road tires, we are looking for wide tires (wider than most of the current tires). Some vintage references exists under HPI Vintage range, and as well within Tamiya range, but none is exact size apparently : I found some 34 mm width HPI tires, and I know that Tamiya has some 30mm wide slick tires. Original foam tires are righ in the middle of that, but on the other hand, the rims where the same except the colour and larger tires should work, as I believe original off road tires were 36mm width... We will see in time...

Beside the wheels, I'm still missing :
- a driver for the Coors
- central shaft for the Coors

For the central shaft, I thought about a aluminium rod in 8mm diameter, but when we tried to work it out on my brother machinery, it did not go exactly as expected due to the vibrations. My brother wanted to find another way to deal with this, and in the meantime, he proposed another alternative solution to try and which could evntually work:

- two wiper blades trimed to the proper length
- two pla parts, fixed with some band

It may work properly, and while I'm not confident in this on the longer run, as long as the blades are in opposition (they are slightly curved), that should work. I will give this a try (for the science )...

[silvertriple]

This afternoon, I put some wheels on my desk...

I started by the complex rims. Shogun wheels are highly refined. They are part of the nicest out there...

First a revolve to set the main bodies


I then did tried multiple ways to set the arms...

Not close enough...

Decided the right way was to loft from a plan tangent to the wheel diameter to a plan perpendicular to the axis and to apply them some revolve to correct what was wrong...

And this is much better... I could not then resist to apply some gold


Then spend a bit of time to create tires (not perfect as I do not have new ones as a reference : this is derived from what I have.

(if someone has brand new tires available, height of the cone, center of the cone measurements please, plus one profile picture )

As there was still sometime, I decided to start the Ninja wheels, satrting by front one. Very easy rim to model. I will need to copy and past as new to derive the rear one from it (there should be Few measurements changing).


(there is just one single meausrement on the spoke which is improper but it is to respect the minimal 1mm thickness asked by most printers.

I have already a quick look at the tires, they are a bit more complex than others I did until now as this will require more than just one sketch per spike...

[silvertriple]

Removing the tire took a few seconds for the rear Ninja wheel...

Took the caliper and measured the width and other parameters required to be changed, and then went back to my stuff to fetch the front rim. This is similar as teh Samurai. both rear and front are different diameter. Finding tires will be as difficult as for the Samurai. Anyway, the original rims are in, and they are a good case for parameterized wheels, exactly like the Samurai, for the same reasons (but it will be less fun this time )... But I won't tackle this now...

[Dadio]

It's strange seeing how you work compared to how I work , I've never used a revolve for a wheel , I'd extrude and off set extrude , but we both used the same method for twisted spokes by using a loft .
Both sets of wheels look nice .