Need help applying ground foam to a large area

[Blind Bruce]

I am about to put down some ground foam to 3 square feet of painted, ridgid foam. The procedure should begin by painting the entire area with a 50/50 mix of elmers and wet water. Before it begins to set up, I plan to sprinkle various shades of ground foam over the whole area. Now.....

Do I spray more 50/50 on the area right away or let it dry and then "seal" it?

Is there any other ideas to cover such a large area?

[carl425]

It's ok to use thinned Elmer's under the foam, but I would not use it on top because it doesn't dry clear. Use matte medium or some other "scenic cement". If you use Elmer's underneath, let it dry. If you use matte medium or scenic cement it doesn't matter.

[mlehman]

For foam scenic materials over such a large area, I put down the materials, arranging to suit, then I mist 90% alcohol over it to wet throughly. I follow this by misting on 50% matte medium (clean up your sprayer right after use or else! ). It's quick, easy, and looks great. Just make sure you don't matte mist anything you don't want to.

[MisterBeasley]

Ground foam or turf?  Turf is small and fine, while foam is larger and clumpier.  There's lots of different stuff on this picture:

The areas which look like grass or dirt are just turf.  The bigger green stuff, both light and dark, is foam.  There is also some static grass here.

I usually skim-coat the surface with a thin mix of Gypsolite first.  That gives me a rough surface.  Then I paint on a "camouflage" pattern of greens and browns.  Actually, I tint the Gypsolite with brown paint, so I'm only painting on a thin wash of green, which is very quick.  After that, I paint on a thinned white glue, about 1 part glue to 3 parts water, and apply the turf.  I put it on by hand so that I can get a more "random" look of browns and greens.  I use 3 different turf colors, most of the time.

I let that dry, then add clumps of foam.  Once I've got them in place, I douse the clumps with isopropyl alcohol straight from the bottle from a pipette, and dribble on the same glue mixture.

[Blind Bruce]

Mister Beasley, your scenery looks great!

Please answer, what is Gypsolite? and what is turf? I haven't heard of either one.

[MisterBeasley]

Thank you!

Gypsolite is a plaster product.  I get mine from my LHS in big 8-pound jars from Scenic Express.  It's rough and gritty, so everything I spread it over has a "natural" look.  The term "Gypsolite" might be generic, like "Hydrocal."

Turf comes in those Woodland Scenics jars.  It's generally very fine, almost like powder, and comes in many colors.

[wp8thsub]

For covering large areas, I typically use 50:50 white glue and water, brushed over a portion at a time.  If you can only cover, say, an area 18" square while ensuring the glue stays wet, then do that and move on to the adjacent space.  For a foam applicator (assuming you're using fine foam), try a "kitchen shaker."  I got a cheap one at the dollar store for layout use.

Here's a scene I've been working on lately, which required multiple passes with glue, dirt, more glue, ground foam, and later will get still more glue and static grass.  Provided you ensure the ground cover is applied over wet glue, there should be no need to go back over the scene to further fix it into place.  I wait for glue to dry and vacuum the small amount of excess.

[doctorwayne]

As you can see, Bruce, there are lots of ways to apply ground cover.
On relatively flat areas, I prefer to apply everything dry - turf, coarser ground foam and clumps, plus ballast and real dirt, too.  Everything then gets a generous misting with wet water (aim the first few spritzes upward so as to not displace the light material).  Once everything is damp, the area can be sprayed more directly.  Don't skimp on the ground cover and especially not on the wet water - that's what ensures that the diluted white glue is pulled completely into the ground cover and becomes invisible once dried.
My landforms are plaster-on-screen, so the ground is pre-coloured with dilute flat latex house paint in a suitable dirt colour.

Here's an area where the ground cover has not yet been applied:

A different area, where the loose ground cover has been thoroughly pre-wetted.  Water will collect in the low spots, of course, and while it will do no harm, you can add extra ground cover if desired. 

Applying the diluted white glue (matte medium works equally-well, but is considerably more expensive):

 

Here's the same area after the glue application has been completed.  Depending on the depth of the ground cover, this can take a week or more to dry.  Resist the urge to touch it - you've probably got lots of other stuff to do to fill that time.

...and the finished scene:

There is no visible trace of the glue, but the material is held in place sufficiently that it will withstand a careful non-contact vacuuming.

If your water is especially hard, substitute distilled water - it's available in gallon jugs at any supermarket and at a cost much lower than alcohol.  An even cheaper solution is to use the water collected by a dehumidifier, but make sure to clean the collection bucket thoroughly beforehand, as they do become somewhat slimey over time.  This water is also perfect for decaling and thinning water-based paints.

For terrain which is not flat, first paint the area with full-strength white glue, then sprinkle on your scenic material, misting it occasionally as you work.  Spray only enough water to wet the ground cover enough that it will draw some of the white glue up into it.  Once this has dried completely, you can go back and add more ground cover using the first method outlined.  Any area can, of course, be added to at a later date.  Varying the colours and textures will add to the realism.
In the photo below, the minimal amount of ground cover evident was applied merely to utilise the run-off of dilute glue used to apply the ballast and rock fill on the track visible in the upper left corner of the photo:

...and here, the steeper areas got brushed-on white glue, but the entire scene to the left of the tracks was done as a single operation:

Wayne

[rrebell]

Gypsolite is a brand name of a plaster with lightweight stuff in it, goes on like stucco. Never did fine it on the west coast.

[cowman]

I bought Structo-Lite which is suppose to be the same or very similar product to Gypsolite.  Got it at my local hardware store.  My layout plans changed and haven't had a chance to use it yet.  Have enough to do a huge layout.

As for putting down the ground foam, I applied it directly to the wet coat of earth colored paint on the foam or whatever was there for a base.  Some folks have said that the paint wicked up into the foam, I did not noticably find that.  If you are applying real dirt, doubt it would be a problem at all.  Even if it does wick up some, it is your earth color and later layers should cover it. 

Don't try to do too large an area at once.  A square foot or two is plenty, shake on the cover(s) of your choice, then move on.  I found that doing a larger area, the "stick" of the adhesive, paint or glue mix, dries up rather fastl

Good luck,

Richard

[CTValleyRR]

I agree with the folks who say keep the area small.  I too work in areas of about 2.25 square feet (that is, 1.5 feet on a side).

My technique is to paint the area with a thin coat of full strength matte medium (buy a large bottle at Michaels with a 50% off one item coupon and it's not too expensive), then sprinkle on a thin coat of turf.  After it's dry (a couple hours), I add more turf, some chunks of ground foam, then mist with 35% rubbing alcohol (70% drug store strength,  diluted 50%) and saturate with matte medium solution.  I make the solution by diluting matte medium 1:4 with filtered water, adding 2 drops of dishwashing detergent per cup, and mixing well.  Then I allow it to stand overnight while the talc settles out.  I decant the solution and throw out the talc.

There are alot of ways to do this.  Experiment until you find one that works for you.

[Grampys Trains]

I agree there are many ways to make scenery.  I use a mix, 1 part sculptamold-4parts structolite/gypsolite, as a base. I paint this with thinned, earth toned, latex paint. Then I apply full strength white glue to a small, about 1 sq. ft., area, and apply different color, coarseness, and texture foam, turf, and grass/weeds.

[bearman]

I usually apply white glue full strength first.  Then the ground foam and/or turf, some dirt, sand (my RR is located in the desert southwest) then I finish off with dilute white glue.  Works great.

[Redore]

I do something a little different.  I start by painting a layer of Hydrocal over the scenery base.  Then I take a flour sifter and sprinkle Hydrocal over the damp partially set plaster.  This draws water out of the wet plaster to set and gives a very rough texture that looks a lot like the turf.  When that sets up firm I brush paint it with latex paint in "grass" color.  While the paint is still wet I sprinkle on ground turf to give varying color and texture.  I then spray the turf with wet water to draw up some of the paint.  When it all dries it looks for all the world like a short grassy field and is an excellent base for brush, trees, and so on.

Turf comes in bottles now, but back in the day when it came in bags I took a clean peanut jar and punched a bunch of holes in the cover with a 16 penny nail and used that as a shaker.

[wickman]

Everyones ground  work looks great.  I  have  in the past used  whats called poly fiber made by woodland  scenic  for starting point , stretch and pull it then lay it over  what ever  the painted surface  is, give it a white glue/ water drizzle and  let harden or keep building  up  in layers with ground up leaves twigs etc and  redrizzle. I've also used ground goop as a starting point, this gives  the raw surface  great  color  and  texture to start with.