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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...

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...

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

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!

Received recently an ultrasonic cleaner (target is not only rc activities, so it is bigger than required - 30L).

I put all the parts of both chassis of this thread in it with water plus a bit of dish soap.



one hour later, my parts are all cleaned. There is some polishing still required on the metal gearbox plate (corrosion), and some glue remaining on the servo area on one of the chassis, but beside this, it's clean. (if I compare to the 4-6 hours spent average on each chassis until now, it will be a big time saver).

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/marui-big-bear-part-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

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...

I really need to complete at least one super wheelie bodyshell for the Super Wheelie chassis...

At the end this is just a question of work. Yesterday I took care of the seats...


And with the seat, we may have already an idea of what it will be at the end...


Today, I took care of the rear...


And a lot of details on the top of the rear...


I'm getting there... There is still a lot to deal with in particular on the bonnet, and then it will be all accessories...
This is taking a lot of time, but it's still fun, at least for me

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?

The overall purpose of the Big Bear chassis modeling was to help a friend who helped me in more than an occasion. He has an almost Big Bear with a broken chassis... And his printer is small...
Today I part the chassis in 3 pieces to allow printing on small desk printer...



Approach is using 6 screws and nut to set sides together (so 12 screws and nut in total).

After a few hiccups my printer is back online... I had some hard time with it to the point I'm more and more considering than rather than buying new old cars, at some point I should trhow it and replace it by something more reliable...

Anyway, today, I started the test prints for the Big Bear/ Super Wheelie parts...


After the print, I pull the diff I used to do the CAD model, and did try the part in...


It drops in, it works, it meshes, and the overal dimension of the diff is the same than with the original part... That sounds good

Looks good , the original part seems to have the land between teeth filled on the sun gear and the planetary gears clipped on the end .
What trouble are you having with the printer ? Both my FDM printers are Ender models and chances are I know a solution , usually it's not the kinematics as they are common to the vast majority of printers except CoreXY . Mostly the problems I had were from the Bowden extruder and the main board , you can change these parts for a fraction of the cost of a new printer .

Dadio wrote: ↑Sun Jan 29, 2023 7:10 am Looks good , the original part seems to have the land between teeth filled on the sun gear and the planetary gears clipped on the end .
What trouble are you having with the printer ? Both my FDM printers are Ender models and chances are I know a solution , usually it's not the kinematics as they are common to the vast majority of printers except CoreXY . Mostly the problems I had were from the Bowden extruder and the main board , you can change these parts for a fraction of the cost of a new printer .

Troubles with the printer are mostly due to a user error... Started a print in PLA with a non dry filament : filament broke in the tube, and I had to change both tube and nozzle to solve it. The fact is every time I'm getting the nozzle done, I struggle to get the level properly after that. There should be a way to deal with this without that much try and errors... That being said, this is not the only grief I have with this printer : I could enclose it, but would need to change the head, the extruder, the power feed and probably the mainboard as well to get something capable to print wider range of filaments... Ultimately, I may go the upgrade route, but to keep it for some purpose while investing in some other IDEX printer with hardened head capable of higher temps to be able to print with supports in different materials and with Carbon filled filaments...
In the meantime, if you can share your own method to level your printer's bed, that may help

And for the remark of the difference on the gear with the original, I may just remove the fillet I have added on the bottom of the gear as it is what causes the difference...

I have my ender 3 just for PLA and my ender5 enclosed and more highly modified for more exotic filaments , so maybe the answer is another printer but finding an all metal hot end , fully enclosed and better main board printer is another level in price

Dadio wrote: ↑Sun Jan 29, 2023 7:30 am I have my ender 3 just for PLA and my ender5 enclosed and more highly modified for more exotic filaments , so maybe the answer is another printer but finding an all metal hot end , fully enclosed and better main board printer is another level in price

Yeah, I know... And probably having pack of issues as well :-/
But well, that's a permanent reflexion, to be clear... Having to rely on online printers for many stuff is somehow a limitation, and it would overcome that imitation as well... But at a price, let's be clear...