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I concur with Chris's method.

Coat the inside of foam tire and outside of rim with contact cement and let dry until it's just slightly tacky. Dip your finger in turpentine and rub it inside the tire and outside of rim, then quickly push the rim into the tire and let dry. Once dry you can true the tires.

The trick is letting the glue dry/tack up first, if you try to do it while wet you just push/squeegee the glue out.

Use a nail file board to gently round off the corners on your lathe after you true the foam.

Thanks , these tires are very tight to manoeuvre about on the rim so I don't think contact cement without the turps is a good idea , I may try the turps on a waist PC printed part to see what it does .
I fitted the tiny rear shocks , they work really well but I now only have damping in roll because of how the suspension works .

This is a possible body choice , it's been kicking around for a while after coming with a PB Mini Mustang

Dadio wrote: ↑Sat Jan 22, 2022 10:53 am Thanks , these tires are very tight to manoeuvre about on the rim so I don't think contact cement without the turps is a good idea

Being a tight fit is normal, they need to be stretched on to the wheel to stay on there. I use Evostik for foam tyres, and back in the day never had anywhere I could store a jar of petrol for this purpose, I just used glue. Coat the wheel and tyre with a thin layer of contact adhesive and let dry overnight, so all the solvent has evaporated. This ensures there is glue covering every part of the join and so it can't be pushed out. Coat the wheel and tyre with a second layer of glue and while still wet push the wheel into the tyre. Most of the fresh glue will get pushed out but this is fine as it's just acting as a lubricant. Leave to dry overnight. These days I usually then run a bead of super glue around the join between the tyre and wheel to stop the foam lifting at the edge as the tyre rolls in the corners.

Although in a hurry, like having to mount tyres at a race meeting, I've also fitted the tyre to the wheel, peeled the tyre back to half way, put superglue in the gap followed by a spray of activator before carefully letting go of the tyre. Turn over and repeat. Gets the tyre permanently attached in a minute and will stick the tyre to the table if you put it down too quickly Using contact adhesive or tyre tape are great because you can clean them up when the tyres are done and reuse the wheels. You can usually just cut across the tyre and then peel it off the wheel, with super glue that wheel is done.

Dadio wrote: ↑Sat Jan 22, 2022 3:47 am Next question , these tires have a 90° shoulder , the road surface and side wall just meet at a hard edge , my mind says that's bad and I would put a radius on the shoulder , this also brings up the question of trueing them , is there an easy way , I mean I have a lath but I've no idea and there might be an easy way ?

Yes the tyres will need truing and squaring up, and the corners rounding off. The easy way is to use a dedicated automatic tyre truer, fit the wheel to it, set the diameter, press the button and watch it skim it down to the correct diameter although it's a bit expensive for a one off.

As you have a lathe you already have a way to turn them down, you just need to sort out a cutter. The cheap and easy way is to use a bit of a hacksaw blade, mounted at a 45 degree angle in line with the centre. You can see how it's mounted on this truer https://www.fastrax-rc.com/image/cache/data/product/FAST2000/gallery/gallery4-600x400.jpg Then just run it across the tyre as it's turning. To finish it off stick a piece of 120 grit sandpaper onto a flat board. reverse the lathe so it's going away from you and use the board to shape the tyre. Most racers use a Permagrit flat file, but again a bit much to spend for a one off.

This video will show you the process of tyre truing https://www.youtube.com/watch?v=0SwQVXO6Mzs

I'll try them on the lath , I must confess I tried using a sanding block and just running them up on the car but it was hard to control and very limited by the diff .

Rear tires trued on the lath , I used one of the drive hubs in the lath chuck to hold the wheel and just used a piece of board and sand paper , worked well enough , going to have to think about a mounting method for the front wheels but its not rocket science .
Next question is what kind of gear ratio to use , I was using a 13t pinion with a 54t spur giving 4.15/1 , it felt over geared so on instinct I ordered an 11t pinion to give 4.9/1 , that still seems high to me but I've never driven a rig like this , anyone have a pointer on gear ratios for this with a 12turn motor ? The ESC felt quite warm after a short test run and the motor was warm but not too bad .

Dadio wrote: ↑Wed Jan 26, 2022 1:04 pm Next question is what kind of gear ratio to use , I was using a 13t pinion with a 54t spur giving 4.15/1 , it felt over geared so on instinct I ordered an 11t pinion to give 4.9/1 , that still seems high to me but I've never driven a rig like this , anyone have a pointer on gear ratios for this with a 12turn motor ? The ESC felt quite warm after a short test run and the motor was warm but not too bad .

From the RC10L2. It also has adjustments for tire diameter. Should be a good start.

54/9 (6/1) is the gearing that I chose for this car, with an 11T triple. However I intend on running slightly taller F1 rubber tires.

https://www.rc10talk.com/viewtopic.php?f=33&t=46756

That's very helpful both of you , I'm running 2.2 rims with an overall tire die of 3.25 " so I'm going to have to do the math thing when I'm sober in the morning

Although it's intended for automotive purposes, the gear ratio and tire diameter calculators work with anything.

http://www.wallaceracing.com/gearcalc1.php

Ran way better with the 11tooth pinion but I've had to do a lot to the steering to get better lock but I've not trued the front tires yet so I'm hoping that helps too , very fast though but the ESC is just not giving me any brakes at all so that has to go .

How bad does that star servo horn throw off the steering geometry? I always try to get the ball cups as close to each other as possible.

Suddenly I want to pop out & buy a 3D printer & an automatic tyre truer.

MadZero wrote: ↑Fri Jan 28, 2022 5:59 pm Suddenly I want to pop out & buy a 3D printer & an automatic tyre truer.

I was thinking more like buying parts from Jeff and Dadio, and using CRC F1 type rubber tires and wheels.

But I've got other projects in line ahead of that.