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Marui Super Wheelie and Big Bear - a project including CAD

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Marui Super Wheelie and Big Bear - a project including CAD

Old 02-17-2023, 09:39 AM
  #16  
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The CJ-7 bodyshell is very detailed, and this turn to be as complex as you may think...

Did multiple tries for the front until I get a way which I was satisfied with...


It took me a while to get to the point of having a front somewhat similar to what I see... And yet, I'm not 100% happy with it, as there is some Fusion 360 limitations thet blocks me to do better...


Compared to the front, the rear is an easy one... And it starts to take shape... Although there is far too many sketches so far...


Here is the body in its current state on the chassis...


There is still a lot of work : the rear end, the top, the elements on the bonnet and the windshield fixation... And yet already about 40 sketches... :roll:
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Old 02-18-2023, 01:20 AM
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Damn, really nice work. There is a lot of people who are interested in what you have going for the BigBear, it's just that people don't have time to look into the 3D ordeal and print for themselves. I'm loving what you are doing but I can't find the time of day to do what you do man, my ass is working hard 60 hours a week besides having to play with my dogs. I would be interested to see what you did with the tires for the BigBear as I'm in need of them to finish my restoration. I have 3 BigBears with nothing butt cracks on the side walls. There is no better looking tires then the ones that originally came with the BigBear as it looks scale and mean. I've tried the Kyosho Mad Van, Tamiya LunchBox, ARRMA tires, ProLine, IMex etc....nothing beats the original BigBear. That's my opinion and I'm sticking to it.
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Old 02-18-2023, 02:38 AM
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I was talking about the rear side to someone... I even took a picture of it...


My thoughts : The designer who made it probably thought that 40 years after him someone would tried to model it in CAD and decided to give him some hard time :-D

Anyway, I decided to cheat, as mentioned earlier... I put a lid on the toolbox and identified it clearly. This car is going to go fast with my improved gears, so there is a fair reason to put a lid on the toolbox :mrgreen:


Then, moved to the seats... They are challenging, somehow... Did simplified them, in a similar way than what I did for the Land Cruiser... There is always a way to do better, but i DId not want to spend too much time for it... That being said, thinking now, I may have done this in Surface mode perhaps in an easier way...


Added the last details : blinkers, room for the windshield fixation, hole for the gear lever and the switch...


And here it is on the chassis...


There is still some parts to do to complete the shell : the dasboard, the windshield. Most of the accessories are common to the Land Cruiser: I identified one difference : the spare wheel is not fully covered like on the Land Cruiser...
That's my next steps for this afternoon, probably in parallel to some Nichimo test prints...
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Old 02-18-2023, 02:43 AM
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Originally Posted by SuperFastSnail
Damn, really nice work. There is a lot of people who are interested in what you have going for the BigBear, it's just that people don't have time to look into the 3D ordeal and print for themselves. I'm loving what you are doing but I can't find the time of day to do what you do man, my ass is working hard 60 hours a week besides having to play with my dogs. I would be interested to see what you did with the tires for the BigBear as I'm in need of them to finish my restoration. I have 3 BigBears with nothing butt cracks on the side walls. There is no better looking tires then the ones that originally came with the BigBear as it looks scale and mean. I've tried the Kyosho Mad Van, Tamiya LunchBox, ARRMA tires, ProLine, IMex etc....nothing beats the original BigBear. That's my opinion and I'm sticking to it.
I'm still working on this at this stage... Have some ideas and projects... but nothing concrete yet, as I need to plan for 60 hours plus of printing to get a mould done to test for small tires before trying to build a Big Bear tire mold to validate the concept. I know many people are awaiting for this. I thought about different options involving flex resin printing or TPU printing : they are too much expensive to my taste, due to the size of the tire (about 140 without taxes and shipping per tire at the best cost I found). And it won't be like a real tire... So the best way to deal would involve a mould and some injection (TPE)... The only thing I can say is : be patient, I'm trying to do something about it.
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Old 02-18-2023, 11:09 PM
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After my last post, I moved over to next complex part : the dashboard... The structure is different from the Land Cruiser, and this time, I had it in hands (I still need to get the one from the Land Cruiser to be able to correct the model). There is a wall closing the bodyshell, and leaving room for the driver feets, and including the thransmission funnel...


A lot of details aalso...


This parts required 3 lofts... And therefore already 9 sketches just for those. Total 18 sketches...


Then I took care of the Windshield... Profile is right, as it matches the sketch on the screen... I corrected the weepers as the right one was too long and the left one was too short :-D


After this being done, I got the accessory from the Land Cruiser and imported them... I noticed that the front of the roll cage is different as larger. The Land Cruiser one was glued and I did not bother modelling it in three parts. I had to redo it for the CJ-7. Which was quickly done, and I spotted a mistake I'll have to correct on the Land Cruiser cage (for which the Dashboard is not properly measured because I did not have it, and it supports the windshield). I sill have the spare wheel to modify to make it more CJ-7... But this is already nice this way...


I do have the intention of doing some rendering of those cars all together... But not for now :-)
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Old 02-19-2023, 10:25 AM
  #21  
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There was two versions of the SuperWheelies with the CJ-7 bodyshell...

One was white, and one was black... The white had black arms, while the black had red arms...






I'm quite sure the Black with red arms was faster :-D

And another chassis family picture...



It's incomplete : there was Land cruiser with blue bodyshell, and additionally, I believ that one of the Super Wheelies had some grey arms, but I'm not fully sure which it was...
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Old 02-20-2023, 11:33 PM
  #22  
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Super Wheelies...



1983 models, They had a 6V chassis and suspension arms colored:
- Super Wheelie - Land Cruiser white bodyshell, arms and wheelie bar were grey
- Super Wheelie - CJ-7 Golden Eagle Black bodyshell, arms and wheelie bar were red

1985 models, 7.2V chassis, with black arms:
- Land Cruiser superwheelie : Blue bodyshell
- CJ-7 GoldenEagle super wheelie : White bodyshell

And a render with the Big Bear and its unreleased prototype:
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Old 03-01-2023, 04:29 AM
  #23  
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The prototype of my Universal Marui Gear (Mod 0.8) set is arrived...

Here is the design:



It was designed to cope with all 2WD Marui cars, and to get as closed as possible of the standard Mod 0.6 gears ratios. It includes even the motor pinions (but I may decide to remove them at the end (not yet 100% sure), it is based on the Big Bear V2 differential design and it was clustered with the intention to reduce the total cost...

I will check the fitting and clearances in Hunter/Galaxy and Super Wheelie/Big Bear gearbox tonight (in both PA12 and PA12/GF).
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Old 03-01-2023, 11:39 AM
  #24  
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I did the tests, and there is some good and some bad stuff

The Differential is a perfect fit, as expected, it works smooth and insert the axles shows the right clearances, and that on all the tests


On the Hunter/Galaxy, I did the idle gear without test fitting the new diff, as I didn't have the Hunter chassi model. Bad mistake. I should have, as I had the idle gear modded in .6 mod to get it closer to the motor to allow the usage of pinions we can find nowadays. The out diff bevel gear is larger on the new diff, and that colides with the idle gear while it was not within the older design. I cut it (removed the 2 mm added on the opposite side from the motor) to test the fitting with a motor pinion. I will review the idle gear and review my file accordingly. Not too much correction : it is adding an extrusion on one side and remove it on the other side.


On the Big Bear and the Super Wheelie, the fit is perfect between the diff and the idle gear, however in one of the configuration, I made a mistake when I set the number of teeths of the pinion, because it doesn't mesh... I did this a morning, and it seems that some home activities were a little bit more disturbing than I expected.


I will modify slightly the motor pinions to make it more resistant : there is not enough material to maintain the grub screw properly, it breaks if torquened too much...
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Old 03-31-2023, 07:18 AM
  #25  
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The final version of the Marui 2WD untiversal gearset is born...


Test fit for Super Wheelie


Test fit for Big Bear


Test fit for Hunter/Galaxy


The Idle gear for the Hunter/Galaxy is on the sprue in two versions : one for standard original shaft, and the second one made to fit ball bearings on a 3mm axle (the original shaft is not a 3mm shaft but slightly more)...
I'll open a Shapeways shop for those soon, as there is already a bunch of people requesting this :-)
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Old 04-01-2023, 05:00 AM
  #26  
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I set a silvertriple shop on shapeways... I had to order a part from my shop, and just noticed the shipment cost which are a bit crazy...
Anyway, it's live now, people should be able to order the part and as well replacement idle gears for this set (that's the Hunter part I ordered as I needed one to replace the faulty one from the prototype, as I needed to order a part to open the shop).

I also tried to make sure the information provided is clear enough so people don't order just the idle gear for their car while it is just a raplacement...

Let's see how this goes... But hey, I wish there was cheaper alternatives for people who needs them.
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Old 04-01-2023, 07:44 AM
  #27  
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What material are your gears made of? The pinion and idler gears should be metal to hold up longer just like the original?.
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Old 04-01-2023, 01:22 PM
  #28  
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Those gears are Nylon Printed using Multi Jet Fusion. Inityally, they were ABS for the Diff and idle gears (Hunter and Galaxy), or Zamac (a very low temp metal alloy) and none actually resisted runs. Further, at the notable exception of the Big Bear V2, all the gears were in module 0.6 (smaller teeth), which means not much material to absorb heat, and they were quickly melting. The combination of Nylon with higer deflection temperature and bigger module (0.8) making teeth bigger with more material to absorb heat should make it more resistant. The motor pinion, however should be replaced by metal pinions for runs (but they should be easy to source). As the idle gear is probably going to be the weak point, I made sure it can be order separately as well... Unfortunately, metal would make this out of reach in terms of costs...
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Old 04-01-2023, 03:28 PM
  #29  
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Originally Posted by silvertriple
Those gears are Nylon Printed using Multi Jet Fusion. Inityally, they were ABS for the Diff and idle gears (Hunter and Galaxy), or Zamac (a very low temp metal alloy) and none actually resisted runs. Further, at the notable exception of the Big Bear V2, all the gears were in module 0.6 (smaller teeth), which means not much material to absorb heat, and they were quickly melting. The combination of Nylon with higer deflection temperature and bigger module (0.8) making teeth bigger with more material to absorb heat should make it more resistant. The motor pinion, however should be replaced by metal pinions for runs (but they should be easy to source). As the idle gear is probably going to be the weak point, I made sure it can be order separately as well... Unfortunately, metal would make this out of reach in terms of costs...
The pinion gear and idler gears are going to fail bad. in nylon. Good only for display. The idler gear in stock metal was the weak gear as was the plastic idler gear in the hunter/galaxiy. The zamac stock metal gears will hold up longer than nylon. Sourcing 0..8 pinon gear stock is going to cost more. today. Which is why I stockpiled all the gears for these kits. It's best to just Rember the good old days and display these kits as time has moved on to better products.
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Old 04-02-2023, 06:02 AM
  #30  
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Lot of Marui stuff those times...

Last time printed the three parts of the chassis to test it. I had to check 2 dimensions : one requiring the 3 parts (body mounts positions), second one being the rear rigid axle position...
I printed all on the same plate, not in an optimal position, and without using the mutimaterial capabilities of the AMS system, as I still have 2 rolls of Amazon basics filament to finish. That makes the case for this. Once those 2 rols are depleted, I will use PETG as interface support for PLA prints, and that will be much better... In the meantime, the quality is not that good, but the target was not really quality...
https://youtu.be/kG9mu75rafQ

The 3 part printed (NB:I removed the antenna supports to get the rear flat on the bed).


With the orientation I used for the print, I'm almost sure the nut pockets are not that good quality either due to supports, but nut and bolts were not required for the test fit...


The rigid axle take place perfectly, and it is moving as it should. I'm happy with this. I have no doubts on the front side, and it is not even critical on front side...


One thing that I absolutely needed to check was the position of the body rear body mounts... I checked with both CJ-7 and Big Bear bodyshells, and it is lining up...


This means it is very good :-)
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