[Kevan]

Hopefully a helpful tool for someone...maybe useful for proxy organisers.

Ground Clearance Blocks.

Three sizes, 1mm, 1.5mm and 2mm

Best printed on an FDM printer

   

   

[Kevan]

I've tweaked these slightly for narrower cars, these three files now have a 30mm wide top face...the original files had a 40mm wide top face.

[Kevan]

Revisited again after printing and testing it needed to be stiffer and have a slight recess to allow for the guide/braids so the car sits on all 4 tyres and not the guide.

   

[MrFlippant]

I like these latest ones, but shouldn't the braid rebate be lower than, if not level with, the road/track surface? The 1mm has it level, but both the 1.5 and 2mm have the braid rebate above the track surface. If you want to make sure the guide/braid is not effecting the clearance check, I'd think it should be lower than the track surface.

[Kevan]

It could go all the way through I suppose.  I left a 1.5mm one print before leaving for work this morning, I'll see how it works later... 

[Kevan]

Total clearance of the guide

   

[Kevan]

v4...guide braid clearance 2mm below the track surface.  I wanted to keep a slot so you can flip the block over and use the other side also.

   

[MrFlippant]

Perfect!
It's too bad the club I race with doesn't use clearance. :(

[Kevan]

What made me create these was the Rally Slotting Proxy which has a ground clearance minimum, since printing the 1.5mm one it's been really handy.

[Nonfractal]

LSC mandates 1mm ground clearance for all points scoring cars. (Those classes  that  contribute to the championship)
A new rule for the 2022 season.
However, this is measured under the motor, not the guide, chassis or overhanging body/spoiler.

After all, it's the motor's :
 -  flux leakage that provides the most gain if set close to the track (if the track rails are ferrous) 
 -  steel can which shorts out the rails damaging power supplies.

The scutineering Process is done with plastic  1mm shim under the motor on a clear perspex block.
If there is daylight under either of the rear wheels, that's a "fail".

DiSCA use a similar methodology but use an engineered steel shim that sticks to the motor for scrutineering.

NWSCC doesn't use a shim and has no min ride height rule. 
Those who go too far eventually realise that a car dragging it's underbelly on the rails is not a fast car.


AlanW