Karl
They are there truly.
Plaster is a shocker for either too dry or too wet when adding track marks, so I got me some Celluclay for my Sturer base.
Here is what I do with plaster.
I place and glue the vehicle on the base. Then I rebuild the ground work along the track to give the vehicle the illusion of weight.
I then run beads of PVA glue from the track rear, 4 runs in all making sure the racks are parallel and gently sloped on the outsides of the run. I add the base material, then paint/dry brush to match the base. I then re-wash the ground base orginal colour back inside the track to further add relief to the track mark.
This method is not as good as using impressing a track run in Celluclay for instance but it does give the vehicle a sense of belonging to the base
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If you look at my T-34/85 post, you can see what I mean.
Now I have the Celluclay, I am using your fantastic base tutorial to make more defined track impressions!
cheers
Mike