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juicedcoupe wrote: ↑Fri Jan 28, 2022 6:32 pm

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.

Just watching those machines do their stuff would be enough for me - car at the end of it is just a bonus

I did some wheels a while back for F1 tires. They work well with the 21t brush motor

GoMachV wrote: ↑Fri Jan 28, 2022 6:36 pm I did some wheels a while back for F1 tires. They work well with the 21t brush motor

The wide 5 pattern wheels looks cool, and scale.

juicedcoupe wrote: ↑Fri Jan 28, 2022 5:51 pm 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.

Yea I had to replace it with a better one with holes closer together , made a kydex plate to adapt it , now it's steering pretty well even on a damp road
Next is to fit another shock to the rear , right now she's not so much a Digger as a Skippy the bush kangero

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 ?

In a normal buggy you would be running an overall ratio around 8/1 to 10/1 for a low turn brushed motor. But of course a normal buggy is a lot heavier than your digger

I worked out a damping solution for the rear , excuse the cheap shock but it's what was laying about , works well with much improved rear end , now I'm running out of space in my road for testing , too many kerbs and not enough straight so I might take it to a nearby car park today to open it up a bit , that is if the migrain I have lifts a bit

Got the front tires trued and made up body mounts , I've not cut this shell only made a single rear body mount hole , it nearly broke me looking at the way the front body mount holes are unevenly drilled , I had to make up wonky mounts to match , on closer inspection the body is marked as a PB body anyway , I went to test it with the trued tires and body fitted and the battery went instantly flat if I get a chance I'll have another go tomorrow . Also got to my local screw shop and finally picked up matching screws all round

Oh my that test drive was disappointing , Just no rear grip at all ,really have to feather it off the line , at least it steers now but man do I need pointers on Pan car suspension set up ! Or I just need to fit buggy tires to it , I can see obvious problems up front as it has single wishbones and tires that need to be flat on the road , my instinct was to give it some droop but I'm not so sure now , maybe harder on the springs and use adjusters to have the arms flat without droop ? Anybody got any tips as I need help

I found reasons for some of the rear traction/stability issues , firstly the rear pod bulkheads had cracked around the bearing seats for the rear axle leaving the axle unstable , also the grommets used for the lateral pivot of the rear pod were not sufficiently compressed also allowing the pod to be unstable in its alignment .
The pod bulkheads were 3d printed in polycarbonate and they had both clacked so for now I've reprinted them in PLA , not ideal but hopefully less brittle , I've also compressed the grommets more to make them more stable .
Up front I've stiffened it up and eliminated droop , hopefully this should help the handling but I can't tell as it's wet out today .