silvertriple

Hello,
initially, I came here to speak about printing and tires molding, but doing some search for a project I'm working on, I found there was this area where people maybe interested by this project (and also because I found there may be some Big Bear fans in this group).

It started with two trucks I received early November. A Marui Big Bear and a Marui Super Wheelie


Obvioulsy, looking at them, there will be a lot of work.

It started one week ago, by tearing down both car to parts and putting everything in a single box



Then and even before doing any cleaning (that will come later on), I started to model part to parts. I'm lucky, I have both versions of the chassis : the 6V (first versions of Super Wheelie (1983)) and 7.2V (Big Bear (1984) and Super Wheelie (1985)). I modeled both chassis to start



You may note the differences : larger battery room for the 7.2V, added holes to fix the steering servo (on the 6V, it was fixed with double face tape).

Then, I modeled the front arms assemblies for the Big Bear and for the Super Wheelie



Next came the gearbox case, common to both cars



Then I completed the rigid axle assemblies, again for both cars...



Next was about the gearbox content. It is slightly different between Big Bear and Super Wheelies : axles are differents. And the Big Bear V2 has a different differnetial, with 5 bevel gears and a module .8 instead of .6 for the former version.
Here is the diff from the Super Wheelie

and the one from the big bear V2


I included all of this in the gearbox for the Super Wheelie already


On the Big Bear, I have completed the diff with the axles, but I don't have the other gears... So if you have a Big Bear V2 near you, you may be able to help me by indicating the gears number of teeth and diameter. This would be very helpful (my Big Bear is actually a Super Wheelie with a Big Bear bodyshell).

Other post will follow once I move forward on this...

OffRoadJunkie

iTrader: (1)

The biggest issue with the Big Bear is the gear box. The holes, where the idle gear shaft seats, is plastic. Those holes wear out fast. There use to be an aftermarket metal collar that went over the seats, so you might be able to find them or, even better, make them.

silvertriple

The V2 gearbox has a metal bearing on the right side... But they did not include one on the left side. I included ball bearings casing on both sides of the gearbox in an effort to make it slightly better...
I may come back later on in this gearbox to try to include the possibility of using some modern gears instead of the original ones...

silvertriple

Finally got the required information to complete the Big Bear V2 transmission thanks to a canadian friend.

Idle gear is 9T/25T mod .8


Motor pinion is 11T mod .8



Once there it was easy to put it in the rigid axle assembly to get it completed.


This time my rigid axle innards are complete... It will be time to take care of the rest...


Speaking of that, I started to model the suspension shaft, and the other accessories. The spring are not exact modelisation. I will come back on those later.


I also started to pull a chassis, and start the virtual build with joints...


And basically, this is highly experimental for me. It is sometimes already difficult to joint a shock with pivot balls at each ends, but here it's a pivot ball, and the combination of a cylindrical and a slot, and it's not working the way I want (and I'm not even speaking about the second shaft...

silvertriple

I decided to cheat and I locked the suspension


and I did the same at the front


For the Big Bear, the next elements will be about the steering servo, servo saver and bumper.

Only thing is that I need to find a Big Bear bumper... And obviously, I need to work out the same for the Super Wheelie, so it looks like the chassis of a car...

OffRoadJunkie

iTrader: (1)

Why do you want to change the gearing? The only issue I ever had were those holes getting bigger and allowing the gears to have too much slop then strip. Once I added the collars, I never had another issue. I had it for years.

silvertriple

Well, my Big Bear is actually a Super Wheelie with a Big Bear body shell: in short, beside the diff, the gears are not the one for the big bear : the gear ratio is likely not adapted to the big bear tires. Based on that, I'll have to do something, and CAD and 3D printing allows for so much that I think about the different solutions...

1995 Monster T

The original BB gear pitch was .6 close to 48 pitch and the V2 used .8 pitch Witch is 32 pitch for stronger gears. I have the original one and stripped out the gears easily. I upgrader the whole gearbox with MIP gears and the case saver for the idler gear shaft. No more problems with stock motor. The super wheelie used a smaller outside tooth idler gear and larger pinion gear. I will have to look As I know I have a set somewhere. I had the landcruiser. Why all the modeling when the process to remake parts is going to be hard and expensive. You have to make the parts out of abs or nylon to hold up. I recall the idler gear was a 28 teeth big side and the pinon gear was 20 teeth for the super wheelie/land cruiser.

silvertriple

Well, I'm not at my first experience in the matter : I completely rebuild a Nichimo Spirit FF from scratch using Nylon (SLS and MJF) prints. Expensive, but at the end, my car is truely unique, and I won't mind running my car like I was 14 :-). Only original parts are the metal parts. All the plastic are printed.



And as for the other projects I have there is quite a good number of them. From the beginning of this year, I did a CAD model for :
- Nichimo Spirit FF
- Nichimo Midships 443WDS
- Nichimo Exceed Pegasus 443WDS
- Hirobo Bearcat SS
- Hirobo 44B-Hilux
- Hirobo 44B Rock'n City
- Hirobo Zerda
And I'm about to finish the Super Wheelie and Big Bear chassis... It's a different approach of RC cars at the end, but it helps to know really a car from end to end and discover a few things on those. I'm not going to print everything anymore, but in case I break something, I'll have whatever is needed to print it directly... And if I publish the parts on Thingiverse (not decided yet for the 44B/Zerda/BigBear/SuperWheelie), it may help some people to rebuild cars...

silvertriple

I started the day by some help on the dimensions of the Big Bear Bumper, first by a Marui fan on a facebook group, and then by a french guy on another forum to complete the information
I did not bother make an exact version of the springs, however...


Then I had a look at the Super Wheelie bumper... It's actually a broken CJ-7 bumper (it was easy to model as I had more than the half)...


The Land Cruiser bumper is simpler...


Then I decided to tackle the Super Wheelie assembly (the front springs are actually following an arc, again I did not bother dealigng with this details)... You may note that I took the 6V version of the chassis. As per the instruction manual, there is not a single change in the way the assembly around the chassis is done between 6V and 7.2V versions...


Once there, next step was about the servo saver. There is a lot of parts, and I'm surprised they did not make it symetrical as it was not very difficult to do it from where they were (The big bear is different, it is intergated to the servo horn)...



When there, I thought I have the tires already, and adding rims should be quite easy. It was indeed relatively quick...



And then I added those beauties to the chassis



The Big Bear is still work in progress. I have the tires already, I need to deal with the rims, and the servo saver to be at the same level than the Super Wheelie.


The Big Bear did not have the servo saver, but fortunately, I should have some in the Hunter/Ganter/Galaxy box, as it is common with those models. I'll have to fetch it in the box, and the problem is this requires a lot of motivation : the box is under a box under a box under a box behind a box under a desk behind some stuff, blocked by other boxes

silvertriple

Yesterday, I checked my files : I had already the tire model, but also the front rim model for the Big Bear... I made the rear rim as well.


Then there was the servo saver... in the box under a pile of bix behind a pile of box under a desk behind some stuff blocked by a piles of boxes... Had a look at my shelf, and the Hunter is there. I took the screw driver, unmount the steering servo and the servo saver, and this was quick to model (much faster than the Super Wheelie's one as there is less parts).

I finally add all of this to the chassis... and we have the Big Bear chassis...





A quick look into thingiverse tells me there is no point modelling the Big Bear Bodyshell as someone has already done this. I'll download those to add to my Big Bear chassis and get it presentable. I'll have to focus on teh Super Wheelie bodyshell and accessories to complete the car... But that's for later...

And just for the sake of comparison, both chassis sides to side :





Happy new year's eve!

silvertriple

First, Happy New Year ! :-)

Yesterday (or last year :-) ), i mentioned a bodyshell on Thingiverse (https://www.thingiverse.com/thing:1079909 ) and Cults3D (https://cults3d.com/en/3d-model/game...art-collection). I've briefly tried to play with the STL files in Fusion360, and it was nearly impossible to join them correctly. I contacted the author to see if it was possible to have a single file for the bodyshell. He shortly replied me to drop him my maial address so he can send me a FBX file... And few hours(?) later, I received a FBX file that I uploaded into Fusion360 to see if I could do something with it...

And yeah... It works. I replied back Tor Arne to thanks him, and to tell him the link he sent worked and that I will find out how to do something nice.


This morning or late last night (and still this morning), I quickly transformed the roll bar and fog light meshes into solid. This was impossible for the bodyshell itself : I had to do something for this, as there is no way to add colors on a mesh...
I decided to add some solid bodies to the mesh, trying as much as possible to respect the dimensions set by Tor Arne... And one by one, I finally had what I wanted for the front face, and I did the same for the rear side...


I also used one of the two center parts provided in the file to work out some windows...
At the end this how it looked in my Fusion 360 design file



I then made a few renders...





I sent those renders to Tor Arne this afternoon, and he replied back with pics of his Big Bear in the grass :-) (not a virtual one)

And then I thought about that pic of the Bear prototype, with Super Wheelies tire, and well, why not, I have almost everything to do it
I took the Super Wheelie chassis file, switch the rear arms with those of the Big Bear, changed the inclination of the rear arms and reset a few joints, and added spacers between the top of the chassis and the nut on the suspension shaft, and I had just to add the bodyshell...


And here are the renders...




Thanks again to Tor Arne to allow me to play with his bodyshell model...

I still have a lot of work to do on the Super Wheelie, and the bodyshell is quite complex... And I'm not sure I'll do this right away

silvertriple

Yesterday, after my previous post, I put the two cars in the same file, just for fun... It's much better when all the wheels are on the ground


And I could not help but adding the Super Wheelie chassis in it...


And I spent the whole night thinking about adding a Super Wheelie body on this chassis...

In the afternoon, I took the Super Wheelie body out of the box...


It's slightly dammaged, I'm still missing a few parts (the windshield support is part of those).
Looking at the body shell, the main difficulty is the bonnet, and beside this, it is a good candidate for solid definition...

I started by putting a plan with the sides definition, an extrusion, then daw a bit of the internals (will have to do seats later on).


Then defined a loft for the bonnet, on a separate body, as I'm not sure it will be shellable


And, yes, unfortunately, it's not shellable... I kept it this way, and applied the shell to the main body, before merging both bodies...

After that, I played with additional bodies and defined the front face...



I'm stopping here for tonight, but this will be fun... And there is some thing fun coming in my mind right now... But it's too early to talk about this...

silvertriple

A week... Almost what it took for the Hirobo Rock'n City body, but not for the same reasons...

The Marui Super WHeelies were a lot detailed, probably more than many of the competition of that time... And people loved them for this...

There was a few part missing with my body (they are somewhere in a box at the previous owner's place, he still searching for them). In the meantime, I decide to move on... There is simple parts and parts more complex. I'm not going to detail everything...

As I did not have the dashboard which is holding the windhshield, I derived from what was around...


The winch is even more complex than the Hirobo Hilux one... I still need to review the bonnet, as the windshield is supposed to have 2 position - one is next to the roll bar, and the second one is on the bonnet.


The roll bar is also a bit complex, particularly the link between the front section and the rear section, define the plan to create the pipe is not really easy...


When having all the parts done (including the extinguisher, I decided to do something for the dashboard. I found some pics, and someone sent some as well... And I took inspiration of them to do something...



Finally, there was the blinkers... I made some, no clue if the measurement is accurate, as I have none.


Then I changed the materials... to get it slightly more realist...


And you know what, I already modeled the CJ-7 Golden Eagle bumper... I should do something to complete it, no? :mrgreen:

silvertriple

Started to work out the CJ-7 bodyshell


I took the same approach as for the Land cruiser... Model half part of the main body, then the bonnet, shell seperated and then assemble them... And here is the progress so far...