I tried searching, but couldn’t find anything here on FSM…and the internet (surprisingly) wasn’t much help, either.
I have a few Tamiya Jeep kits that I want to get started on, but having a real Jeep, I know that the tires are not solid, and have some natural sag even at normal highway pressures.
How do you all sag the rubber tires that come with your kits? Thanks in advance for the tips!
To get my cars to look like there’s some “weight” on the tire’s, I sand down the bottom of the tire’s a little.
For a “totally” flat tire I sand off A LOT ! ( I sand untill I wear a hole into the tire and then “roll” the sidewall over onto itself.)
Ditto to what was said above by littletimmy. I also usually sand the entire tread to get the shine and any attachment stubs off the tire for that “worn” look.
Jim [cptn]
I have a small sealing iron I used to use for Monocoat in my RC days. I heat it up to a medium temperature and press tires onto its surface. The advantage over sanding is that it bulges a bit in addition to flattening a bit.
Be careful with how much “sag” you add to your military tires. Tire manufacturers use several different compounds of rubber in the tire make up, also they add ALOT of extra plies to the sidewall and tread so the vehicle can operate on unimproved surfaces without damage.
Those extra plies make the tire very rigid so even at lower pressures they tend not to bulge.
More modern vehicles have a run flat ring inside to allow the vehicle to get to a repair area so even “flat” there is little bulge.
The ideas and techniques mentioned above are both sound and work well and really do add depth and realism to a model. Have fun, good luck, and show us your finished project please.
For tire “bulge”, I’m like Don. I’ll heat up the part and lightly press it on the bench to get the amount of bulge I’m looking for. Mostly do aircraft models though.
Military Jeeps are fairly lightweight, and won’t have much if any bulge in a static situation, at least till you start getting to Hummers and above, and even then you wouldn’t see much.
Hi Don , Great idea ! I got one. I have been using a hot chisel , tricky but works. I’m going to go dig my iron out . Aardvark
Thanks for all the great suggestions! This is a civilian Jeep, so I’ll give it a little more sag. Thankfully my workbench is in my garage, so I can always just look over at my own rig to compare. 
Good points on the military tires, I didn’t realize they were constructed that way (I only rode in HMMWVs, never drove/maintained them).