Rocker roller 3t Gaurd clearance

Hi all,
This week I'll hopefully start building my flat top trailer.
Tray size 2.2x4.8, 3tonne rated,
How much clearance do I need to allow between the tray above and tyres to allow for the rocker rollers to move? Is there a formula ?

Hi, as a general rule, I use the distance from the axle to the chassis as the distance between tyre and mudguard.
Kryn

what have you decided to set it at Sean?

I'm contemplating a flat top build myself, but can't seem to get components cheap!!!

any clues?

meadow

I ended up allowing about 140mm clearance. Looking at all the trailers on the market they look as though there is less clearance than what I used. Hope it works out!