Limitless JoshJosh’s build - Mods and Batwings, and other 3D printed parts for Limitless

[joshjosh]

I started this post in the welcome forum, thought I’d move it here. I’m making some progress on 3d parts. I have the front wheel aero infills, the back wheel aero infills with rear side skirts. Then of course, the piece I’ve been working on, the Batwing. I’ve since found that changing to a .6mm nozzle increased strength by about 25%, but also has increased weight a bit. Still left to do on the agenda is create the side skirts, and the front wing. You may notice I’m running an Infraction front spoiler, it’s much better for aerodynamics, and I will be designing the front wing around this spoiler.

materials - all the screws are titanium, and the material is polycarbonate with carbon fiber. Printed in a heated chamber 3D printer for superior layer adhesion.

 

[joshjosh]

Does anyone else’s front spoiler tilt up at the front? My nose doesn’t become parallel until my nose touches the floor.

I’d be willing to give out 1 set of these to someone that has posted videos of 110mph, and is willing to post an honest review of these.

 

[joshjosh]

Posting more about my build. Here is the carbon fiber servo adapter, I added some spacers, as the part calls to remove the side skirt mounts. I want those to stay for the side skirts. Fun fact, side skirts were outlawed in F1, because they increased lap speeds too much. I also 3D printed a power button mount for my Hobbywing ESC. I zip tied it in place temporarily. I also have the aluminum GPM upper arm, this has a nice lock screw to keep the camber in place. Not sure if you can see the servo screws, but I installed the 1up servo screws, I love those things! Servo is secure now, no doubts!

 

[Monster Dork]

As far as race car aerodynamics goes, you want your splitter to be long enough so that it is the sole leading edge. Its job is to split the air above and below the car. It looks like your front body plastics are leading, defeating the splitter's function.

 

[joshjosh]

As far as race car aerodynamics goes, you want your splitter to be long enough so that it is the sole leading edge. Its job is to split the air above and below the car. It looks like your front body plastics are leading, defeating the splitter's function.

Thank you for your comment, I absolutely agree! I put the nose piece on for the picture, but I’m completely redesigning a front wing, that will fit the Infraction splitter. The Limitless front splitter is full of sharp angles, not ideal. Also the front splitter points up, which is great for “All Road” bashing. For onroad bashing, adding 3mm of spacing puts the front splitter in a much better angle.

 

[joshjosh]

To accomplish this, you need;
2x M3 3mm spacers
2x M4 3mm spacers
2x M4x20mm flat head screw
2x M3x20mm flat head screw
After this, everything lines up as it should for me, and doesn’t change your suspension/steering geometry.

 

[joshjosh]

I’ve also added the titanium center shaft replacement kit, and rear axle kit from ScorchedRc. The silicone bushing for the rear axle really reduces slop. The overall driveline feels very much improved. I’ve also added the titanium turnbuckles, which should help reduce overall weight.

 

[1coopgt]

To accomplish this, you need;
2x M3 3mm spacers
2x M4 3mm spacers
2x M4x20mm flat head screw
2x M3x20mm flat head screw
After this, everything lines up as it should for me, and doesn’t change your suspension/steering geometry.

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Looks good. What were you accomplishing sorry . You said "to accomplish this" as your first sentence.

 

[rotauq]

To accomplish this, you need;
2x M3 3mm spacers
2x M4 3mm spacers
2x M4x20mm flat head screw
2x M3x20mm flat head screw
After this, everything lines up as it should for me, and doesn’t change your suspension/steering geometry.

View attachment 144522

View attachment 144523

View attachment 144527

When you raise the rear (rake) you actually want the upward angle of the splitter

 

[juulrc]

I started this post in the welcome forum, thought I’d move it here. I’m making some progress on 3d parts. I have the front wheel aero infills, the back wheel aero infills with rear side skirts. Then of course, the piece I’ve been working on, the Batwing. I’ve since found that changing to a .6mm nozzle increased strength by about 25%, but also has increased weight a bit. Still left to do on the agenda is create the side skirts, and the front wing. You may notice I’m running an Infraction front spoiler, it’s much better for aerodynamics, and I will be designing the front wing around this spoiler.

materials - all the screws are titanium, and the material is polycarbonate with carbon fiber. Printed in a heated chamber 3D printer for superior layer adhesion.

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can we download these wings somewhere? becouse the look so awesome i want them on my car!!!!!

 

[joshjosh]

Sorry I was away from the game for awhile, I've actually been redesigning. They have a hinge pin and an arm to adjust. I also learned a lot about aerodynamics, and so I've updated quite a few features.

 

[joshjosh]

I've posted my side skirts here 54mm wide with a body-lock;
https://www.thingiverse.com/thing:5826030
Let me know what you think! I can make adjustments based off feedback.

I had a hiccup with my 3d printer, but I plan on making these commercially available using PC-CF very soon. The ones I have printed have been really tough.

 

[joshjosh]

When you raise the rear (rake) you actually want the upward angle of the splitter

Sorry, but that simply isn’t true. The worst thing you can do for a front splitter is to have an upward angle. Even with rake the splitter tilts up, and the rear end will squat when driving, creating upward lift at the front splitter. I’ve attached a video that does a very good job at explaining this
Front splitter video

His videos are well thought out, and he has the wind tunnel tests to prove what he is saying. Unfortunately, with the design of the Arrma chassis having that angle at the front, not only does is almost guarantee the front splitter to tilt up, it also creates heat on the driveshaft. ScorchedRC has fixed this issue on the Limitless with their Triton driveshafts, but that is just patching the root cause.

 

[rotauq]

My rear end doesn't squat more than 4mm, so i guess there we look different at things. 10 months ago

 

[joshjosh]

How much rake do you have? Is your front splitter atleast level while sitting still? Sorry for the delay in response. I recently had a daughter, and I’ve been spending a lot of time with her. She’s old enough now, and she also loves RC cars, so I’m getting back into the hobby.

I tried raising the rear end before adjusting the front splitter. No amount of rake would fix the front splitter on mine. Ideally you’d have a slight downward angle, and even with the change I made I haven’t achieved that.

 

[rotauq]

As the front does have some travel and it squats the angle increases. I have my splitter at like 0 deg, whiles the chassis has a ~3deg rake. when it squats it gets higher

 

[joshjosh]

As the front does have some travel and it squats the angle increases. I have my splitter at like 0 deg, whiles the chassis has a ~3deg rake. when it squats it gets higher

Interesting, I have my rear end completely raised up, and even if I push the front end to the ground with my finger the splitter still has an upward angle.

To the point I can completely remove the front wheels, set it on the ground, and it still has an upward angle.

 

[rotauq]

Your tower to front brase could need some adjustment (some rings maybe) else its time for a heatgun i'd say or

 

[joshjosh]

Your tower to front brase could need some adjustment (some rings maybe) else its time for a heatgun i'd say or

I can take the front brace completely off, and it will still have the same angle. You can see from the base design of the Arrma chassis that the front end is designed with an upward angle. Also, when accelerating the front end actually lifts up, and the rear end squats down. Only during braking does the front end drop.

I did manage to adjust my rear end until it hit the shock ends, and then the splitter was level when the front hubs were slightly hovering above the ground. I’ve seen many posts on here about the front end lifting up when they took the front aero wings off, that is because of this splitter.

Picture of the base design with front upward angle.

 

[joshjosh]

Your tower to front brase could need some adjustment (some rings maybe) else its time for a heatgun i'd say or

I have a V1 Limitless, and I ordered it at prerelease. I’ve only ran it twice, so it’s still pretty fresh, but It looks like at some point Arrma addressed the front splitter issue by changing the angle of the front bumper. On the right is my original bumber, and on the left is a new piece I just picked up to check. You can see the angle at the very front has been changed.

Edit: I also noticed the new versions of the Limitless front splitter have countersunk holes for the screws, so I also picked up one of those.