Thanks guys - you must be up early in the morning!
As you can see I got a bit carried away and missed a few steps with the camera.
I cut one hundred popsticks into thirds to give me 300 miniature railway sleepers. Forrestfield Speedway was built in an old gravel pit and after a spectator fatality when a supermod broke a steering arm and ran up the bank, the WA Hot Rod Association spent weekends embedding vertically a zillion railway sleepers into the gravel. Talk about a fence that took no prisoners!
I dragged a hacksaw blade over each of the popsticks to give them the texture of weathered sleepers and then randomly sprayed them with grey and flat black primer. I then glued them to the Masonite perimeter that I constructed earlier.
My work takes me into the Western Australian goldfields in the outback and the red dirt there is very fine, almost powder. On one trip it was raining so when I got back to our branch I broke some dried chunks of mud off the ute and took them home. I brushed PVA glue over the track and then sieved the red dirt onto the track to get a clay effect.
Remember my wife's brickwork? The leftover dust and crumbs from cutting bricks was used to fill in the infield with a coarser dirt. This is very much how I remember Forrestfield, the local dirt track I attended as a teenager.
That Bondo I mentioned was getting rather stiff so I sacrificed the rest of the can and built up the corners with some gentle banking. I also used the last of the Bondo to blend the infield down to the track.