Again another Marui project : Super Wheelie and Big Bear!

[silvertriple]

ABS prints are really clean with the X1C... But somehow, sometimes, I have the feeling I'm defying the gravity...



Those prints are dond arleady and were successful... And due to the support position, they are much better than my red test print in terms of quality.



I've launched the front and center part of the chassis, and the result is not yet ready...

[silvertriple]

Half fail for the last plate of prints...



I've been slightly too optimistic when pushing the printer boundaries in terms of gravity, as the front part is missing bumper supports...

At the end I decided to keep the printed parts for the presentation table, and the printed chassis will not run next this week-end...

The Super Wheelie rigid axle assembly is built with a RS-540 SH which fits the gearbox, new wires and printed transmission, as the real goal is to be able to test it...


I'll continue the build later on tonight...

[silvertriple]

Yesterday night, I had a Super Wheelie with a Big Bear front train, as the front knuckles axles were nowhere to be found in what was delivered with the car (there is always a problem ). I found the required screws this morning and the problem is solved. The test chassis is now ready


It remain a bit of work :
- print tpu internal sleeves for front tires (there was not initially I believe, but one of my friend created some and uploaded them on Thingiverse)
- clean the rims
- letter the tires
- assemble the bodyshell. It won't be perfect, but the target is really to be able to test the car.

on the Big Bear, i'll have to do the paintjob today, so still a bit of work

[silvertriple]

There was work being done...




And after a print and some paint applied (unfortunately, no stckers to match what was needed)...



Ok, there was not so much work : I did nothing on the bodyshell, it was good to go... It may require a bit of restoration, the lights are not working, and it would require me to butcher the front to do something about it... No time for this right now, I'll see this later. But for the time being, the gear set test ring in Super Wheelie configuration is ready

[silvertriple]

The Super Wheelie done, the afternoon remain for the Big Bear paint job... I had quite a good idea of how I wanted it to be... "SImple paintjob, dual tone, gun metal and silver, provision for lights later"

And let's be more specific... I started to watch The Mandalorian with my son the day I finised the paintjob of the Ninja, and I though gun metal would go nicely with a Mandalorian themed bodyshell . It's a bit anachronic, but I don't care


Gun metal, then silver, then black to back the silver...



And here is the Big Bear with its bodyshell...



I'm ahead of my plan of a few hours... I have a set of spare RX and Servo, maybe I could build another car? (ok, no, I can't do that, as I suspect the RX of the ESC of the Fantom to have an issue, and I really want this car to run as well...)

I'll have now to prepare my stuff and not forget remote, battery and chargers

[silvertriple]

I did aanother try with 1.5V battery and the light is in... There is actually leds in the Super Wheelie bodyshell. until know I was thinking it was only light bulbs, but they did not work. It's just a question of connecting the right wire on the right pole... I took the solder iron, and did a small connector...
And theres is light now

[silvertriple]

One single pic with my whole Marui crew


There is others, but not in presentable state yet

[silvertriple]

The sixteen cars I went with in Montluçonnaise 2023 all made at least a few laps of run during the event...



And this included the Big Bear, the Super Wheelie and the Hunter (I still need to mount a video of the runs )...

The Big Bear ran a lap and about 2/3 of a second one, and then stop and did not move anymore.
Upon inspection, the 9T on the idle gear did not survived the run.


It clearly needs to see a dentist . I replaced it by another one, and will try again during next event or before...

For the Super Wheelie, on Saturday, i put it on the track, and it made about 3 meters... What a success! I opened the gearbox on the next day, and I was able to run it for quite a good 7 minutes and the transmission is still alive. I will do more tries next event. For the Hunter, it ran quite nicely with a Tamiya Sport Tuned motor. I made a 7 minutes session with it, and again the transmission is still alive at the end. That being said, there was some transmission noice probably due to diff skips. Something I did not have with the Super Wheelie. I've planed to open it for inspection before next event...

Beside this, I've modified my 3 parts printable chassis to ease printability. The best way to print those part is with a quite unconventional orientation, and it happens that elements in the air (on top of supports) are not always perfect. Adding walls to join them to the other side shoul make this easier to print. I did it when I thought it would bring improvements.


- at the rear of the center part : a top bar with the same thickness as bot side of the chassis, and a wall of 1 mm which can be removed afterwards easily.
- on the front part, I bridged the parts

The better orientation I found for the print is on the antenna post for the rear part, angled on the battery pod and rear for the center part and on the rear top upside down for the front.



I've checked holes and nuts dimension : holes need to be drilled to the right diameter (I won't change the tolerance as in case one wants to print it in MJF it is fine while it may be tight for FDM depending on the printer), and nuts are entering in their position when force is applied which means they won't move to much if the chassis needs to be tear down for maintenance, unless you really want to get the nuts out...

Still a few checks to do, but soon this will be published. I'm considering as well putting chassis, gearbox and arms on Shapeways...

[silvertriple]

I ran the Super Wheelie and the Hunter during the vintage event last week-end...


Both cars have now some run time, as they both got run time during the event in Montluçon as well... I'm not going to bet on Super Wheelie's idle life span, but for sure the wheels on the Super Wheelie are easier to entertain for the transmission than the big and fat Big Bear wheels... And considering that both Hunter and Super Wheelie differential are still working, i'm going to try a metal print this time. Ordered idlers for both Super Wheelie and Big Bear in metal print (SLM) to do a test. I had to try. Hope to see this in a week or two...

[silvertriple]

SLM prints arrived today...


The hole for the shaft seems good, next will be to test those inside the Big Bear and the Super Wheelie gearboxes...

[silvertriple]

The Big Bear is upgraded with the new metal idle gear


Now we will see if the diff is resistant enough...

[Dadio]

Those look way better than I expected , hate to imagine the cost though .
What do the teeth look like up close ?

[silvertriple]

Those look way better than I expected , hate to imagine the cost though .
What do the teeth look like up close ?

They look good... Cost wise, it's not Shapeways, and way much cheaper. I was actually surprised by the cost : it was the minimal fee from that provider. A idle gear for the Hunter would be however much more expensive...

[Dadio]

Makes you think all metal transmission for vintage cars being within reach , to my mind the gears are the biggest bottle neck to really driving it like its the 80's

[silvertriple]

I asked my son to take a video while I made the gears spinning with the Big Bear...


This is just an extract. About 15 minutes of run, quite bestial, and the motor was really hot at the end (Marui 480 RS - hopefully I did not killed it). The diff is still alive and smooth at the end of the test run....

Looking at what it supported, it seems I'm on the good path. I will have to test more, but it is definitely different from the test with the Nylon idle gear which required a dentist after a lap on the track