A new project - Nichimo Spirit FF - The first of a kind

[Dadio]

With PLA could you kind of print them tight fitting then warm the ball up and squeeze the cup parts onto the ball , get a really good fit ? Or design a custom part to use bigger pillow balls ?

[silvertriple]

I juts weighted the car:
Total weight (without battery) : 1320g - Front 817g, Rear 503g (62%/38%)
Let's keep in mind this is a FWD car.

In comparison,
- Marui Hunter (RWD) is 1117g - Front 370g, Rear 747g (33%/67%)
- Tamiya Hornet (RWD) is 997g - Front 370g, Rear 627g (37%, 63%)
- Samurai (4WD) is 1244g - Front 484g, Rear 760g (39%/61%)
- Tamiya Super(Hot)Shot (4WD) is 1451g - Front 681g, Rear 770g (47%/53%)

I can't unfortunately do valid comparisons with my Kyoshos, as they are all running brushless motors, and they are heavier than their brushed counterparts...

[silvertriple]

With PLA could you kind of print them tight fitting then warm the ball up and squeeze the cup parts onto the ball , get a really good fit ? Or design a custom part to use bigger pillow balls ?

The place is a bit constrained. There is no room to make it bigger, the cups placed on the top of the arms, rather than in the arms like on the Samurai... I will probably need to review both the arms and the cups... That being said, I could still use the original parts for that (they were proper, they were working well, but they don't have the same red).

And the tight fighting, I fought about it, tried it but it's not really working well in this case, as no room is still the issue (there is part of the cup entering in the arm - at that place in the best case scenario with tight fitting, you have about .70mm of material - not enough to make it strong, I believe - it's probably also what makes the ball so prone to pop out with the nylon, as it is quite flex there. I could think about smaller pivot balls, but I would need to fit them in the proper diameter for the knuckles (M4).

That being said, I could rethink the knuckles to adapt them to smaller pivot balls (M3 diameter based), and make suspension cups with more material (which could solve the problem as well).

[silvertriple]

I 'm not happy with the printed suspension cups and I will get new one printed: pivot balls pop out fare too easily. The ones printed in FDM don't resists, there is not enough material and no good orientation for that.

The vintage event is going to be this week-end and there is no way I'm getting parts printed on time... And I want to run this car
I decided to apply a sort of plan B...

I had this I used once on a motorbike to secure something...


And I made this:


This is the cleanest way I can think of as a solution

[Dadio]

Ha ha that's the Tamiya Rough Rider / Sand Scorcher mod , I did the same on my original Hotshot when the Alloy balls wore out . Should work though

[Dadio]

Are they 2 piece or all one part that just snaps on ?

[silvertriple]

They are 3 parts...
But I did something wrong with the model at that time : I was not thinking printing, and I probably worked too fast, and forget an extrusion on the two parts that goes around the ball and snap in the chassis : it's missing a bit of material, and therefore, the nylon is too flexible... I'll get them reprinted with the proper design once I'll launch the print for the Exceed...

[Dadio]

Just found them in an earlier picture , lower is in two parts and the upper one part , all very small

[silvertriple]

Just found them in an earlier picture , lower is in two parts and the upper one part , all very small

Yes, that is the problem. Samurai suspension cups are quite solid and practical compared to those ones... Making something easy to print would mean enlarge the hole on the arms, and redesign it completely...
Nothing impossible when you print everything, though... But the real issue is that I forget one single small extrusion, and that makes the whole difference... At least those I'll print for the exceed should not have this issue...