2.2" ZigZag Tire Insert (Foam) for RC Scale Crawler

Just to make things clear, my designs are protected by copyrights laws. It is not authorized to distribute or sell any of my designs without prior written authorization from myself. Even if you modified my original design. Thank you.

UPDATE 1/15/2023 Added 126mm diameter version for 2.2x5.4 XL tires (like Prolines 2.2" SX).

UPDATE 10/16/2022 Added 135mm diameter version for 2.2x5.7 tires.

UPDATE 1/7/2022 By request, added 2.2x5.0" model to fit KLR M/T kind of tires.

UPDATE 1/7/2022 More testing with infill values surfaced that 3.5% to 6% infill is ideal. For pure crawling, 3.5% is best, giving a super soft outer. Also found out you could reduce Flow to let's say 80% or use a smaller nozzle (e.g. 0.3mm), resulting in thinner lines and an even softer overall insert, but need to keep an eye on layer bonding. Again, this is all with TPU 95A from Overture. You could end with similar softness without changing infill but using other softer filaments, like 85A (NinjaFlex) or 60A (CoexFlex), but they get more expensive. This will help get the exact outcome you are looking for.

This is a tire insert model to print in TPU for 2.2" wheel diameter tires for RC Crawlers/U4RC/Scale rigs. There are many models included, for standard 5.4", 5.5", 5.7+", and wide 5.75+" tires(usually called 2.2" XL or tall tires).

The model has 3 layers that provide progressive resistance to the tire surface, from very soft to stiff in the center. This allows RC cars to have great traction while keeping the tire shape, adding grip, and making the car predictable during crawling, trailing, or racing.

These models cannot be stretched on the X/Y axis (insert diameter) since it will impact the design, but you can stretch them as you want on the Z-axis (insert width) if you want to fit them in a wider tire or wheel.

Check video explanation with assembly here: https://youtu.be/uuzWVgP8pX0

Read 3D printing settings carefully, as is critical to get the right outcome. Each print will take ~9hrs if set up correctly. If you need help, please reach out on my Facebook page: https://www.facebook.com/groups/d440rc

You can sell 3D printed parts designed by D440RC, but need to comply with four simple rules: 1) Respect the brand, make it clear this is D440RC design, and don’t change the original name/brand helping advertise model purchase in Cults, 2) you need to buy/download the models you want to sell, 3) prints must be in good quality, 4) you can only sell 3d printed parts, you CAN NOT sell/give away the models/files, those are only for you to keep.

The model uses Ultimaker Cura slicer infill patterns to model the soft layers, providing full flexibility to the user to configure the tire insert as they like. The model will include 3mf file to open as "project" in Cura, which includes the print settings.

After several testing, the best infill in my experience for RC Crawling/Trailing use cases is Gyroid with 6% Infill. Infill UP or DOWN if you want a softer or stiffer insert. Between 5 and 10%, I found to be good, but 6% was the magic number for me but depends a lot on the filament you are using.

This must be printed in TPU (tested with Overture TPU 95A), 0.4 or 0.3mm nozzle, wall line count 1, and 0.2~0.28 layer height. Make sure your TPU settings are performing well. Printing Gyroid usually needs good cooling and slow speed (I do 20mm/s for infill and 100% cooling fan - but this will depend on your printer capabilities).

I also added two "Setting Overlaps" in Cura, one at the bottom of the model and one at the top. This allows adding "Wall Line Count 2" to get a stronger wall on the curved corner of the outer layer of the model. This is also part of the 3mf project file. The purpose of the setting is to make the tire insert to support better the RC car on side crawling.

Here's a video with some tips to get the desired outcome: https://www.youtube.com/watch?v=7GkwF7k0koY