Flexible thickness?


#1

Hi there.

When looking at the images that pop up when you search for Formlabs Flexible Resin, there are a few rc tires. Having been in RC a while back I thought printing a tyre might be fun and a good test for the flexible material. Please note, not the elastic.

A decent RC tyre generally has very thing side walls, probably no more than a mm, will the flexible cope with this?

As the tyre would basically be a profile with a thickness I’d have to build in some infill to give the tyre some rigidity so it wouldn’t just be a shell.

Any ideas or suggestions?

Many thanks.


#2

Three kinds of tires-

Solid rubber- these are just solid- they might have openings or empty spaces for weight savings. But can be printed as long as they do not enclose air spaces entirely.

Rotomolded- these are how most RC airplane tires are made- a measured amount of rubber is sloshed around inside a closed mold, coating the inside of the mold like pepto bismol. what you get out is a sealed- hollow- airfilled pneumatic tire.
These can be very thin walled, and so flex, and yet they rely on the air trapped inside to give them increasing resistance to additional deformation… they act the most like actual tube and casing tires.

To make these using a Form 2 you would do best to print the MOLD- and try rotomolding by hand- or cobble together a small motorized rotomolder you could use at home to tumble the molds until the rubber you put inside cures.

Casing tires
these are closer how actual car tires are- or inner tubed tires like bicycle tires. this is a thick tread, thin walled tire that is open internally to the rim.
This can be done on a Form 2 although you might add ribbing internally to help the tire hold its shape as you likely will NOT have pressurized air inside.

You can also print these very thin walled and then fill the internal space with an expanding urethane elastomeric foam to add resiliency.


#3

Have you printed with flexible before? The material has a very low tear strength unfortunately - you can still try to print those tires, but I think @Sculptingman’s suggestion with the rotomolding mold printing would be your best bet to get rugged, resilient tires.