Plaster of Paris Roads HELP!

You didn't let it cure long enough.

I'm, not great at scenery but I use a water base paint flat black  diluted  and brush it on. If it's too heavy lightly sand it , it  looks ok but I'm sure you'll hear from guys that really know  their scenery  stuff.

I use a mixture of India Ink (1 teaspoon) mixed into rubbing (Isopropyl) alcohol (1 pint) and just brush it on.  The more you use, the darker the road!

Plaster takes stains well and it will never come off.......

Why plaster???  I like dry wall mud....cheap, ready to use....more work time....takes paint perfectly.....

Woodland Scenics makes excellent coatings for road surfaces. Their Road System TOP COAT comes in either Asphalt or Concrete Asphalt part # ST1453. Very easy to use and gives very good results.

I mixed color into the plaster so it was colored all the way through. That way you avoid those white chips.  

I agree with Vulcan, I think your paint problem may be because the plaster has not dried thoroughly yet.  Although it seems dry on top, moisture will continue to creep up until it is finally cured.  Depending on the humidity in the room, it could take days.

I used a dark gray acrylic paint first and brushed it on.  Then I took a lighter gray, poured a puddle of it in a plastic lid, and touched a slightly dampened regular household sponge in it, and dabbed the road surface with it.  It looked so real, and you can vary the degree of the lighter gray by touching it more than once in some areas.  If you want newer looking roads,  use the methods Gregg or fctthlw mentioned, and use a darker gray with the sponge.  Jim Barrett was very impressed with the realism of it when he was here.  If you mess it up, paint over it try again.

Mike

Agreed.  Their plaster product, Smooth-It, et al, is perfect for creating roads....asphalt or concrete.

Here's the related products...    http://woodlandscenics.woodlan.../category/RoadSystem

Their scenery how-to book and video covers it all in great detail.  The Paving Tape is especially nice in creating free-form roadways/sidewalks. 

FWIW...

KD

Would also recommend Woodland scenic road products.

Smooth-it is fast and easy to work with and produces great looking results.

And believe me, I am no artist.

Durham’s Water Putty.

I used ready-mixed joint compound and dumped in black acrylic paint, roads came out great. Like the other methods it can take several days to dry