15mm Chicago Terrain Board Concerns?

[Featherstone]

More general WIP thread in the Pulp section, but I figured my design questions should be here instead:

I’m building three modular and independently-playable board pieces: a 2’x3’ neighborhood encircling a park, a 2’x2’ intersection with a prominent church, and a 2’x3’ seedy riverside docks street (concept below):




But I ran into a snag on some board design concerns. Questions:

• I’m afraid of board-warp, especially at this scale when board mis-matches look like fault lines... how do I prevent this?
• The docks section means that the entire board must be raised to accommodate... so should the board be a solid 2” of some material? Or like a hollow platform?
• I only have experience making terrain boards out of “blue foam” on an MDF base, but the edges are very soft and vulnerable to ugly chipping... how do I protect the edges with a crisp, sturdy dark material without creating a visible border on the play-surface?

How ought I to proceed? Also would appreciate any related advice on urban terrain board creation... anybody already doing anything similar?

[von Lucky]

Trying to get my head arounf this - you're 3D printing the whole table?

For board warp maybe gluing the elements on something solid like 6mm MDF or similar? In addition, plenty of 15/18mm scatter terrain (cars, bins, newspaper stalls, etc) will assist with covering the joins.

The docks section would be needed every game, so I would just build it as a tray (with the wharf walls along the required edges), and the other city boards on a temporary platform. Or a permanent one if that's what you prefer. (so solid, but 2" of dense foam could be enough). By having it on blue foam, you can having less dimensions than the board above it, creating a recess for the sturdy dark material (painted MDF or plastic, etc). 

[FifteensAway]

(Not sure where the 3D print thought comes from - maybe the visual included by the OP which I only interpret as a design layout, not a print model.  I could be wrong.   )

Assuming you are using Blue Moon's fantastic Chicago buildings?  Yes or no?

Either way, my approach would be to use underlayment, about a 1/4" thick material similar to plywood.  Create a sandwich of this material using 1" x 1" hardwood as the separators.  Glue and screw, countersink the screws, putty, smooth, allow to dry and sand.  For the port area, jigsaw out the actual port (edit: only jigsaw the top layer of underlayment, the 'top' of the bottom piece will be the 'water' surface)and use well placed 1x1 material to support, can use shaped insulation foam covered with spackling compound wherever there is no 'wall' between street level and water level.

Because the material is thin, the board's will be pretty light but with the hardwood separators glued and screwed, it should remarkably strong.  Using care building by this method, you should not end up with 'warping' so not 'fault' lines to worry about.  But always store flat just in case.

Underlayment comes in 4'x8' sheets locally so it does need to be cut to size.  If you can, have a Big Box store cut it to size with their large cutting tools.  A lot easier and more reliable and accurate than cutting such a large sheet on a table saw at home - if you had one. 

Oh, underlayment is used as a base for laying flooring material in some applications thus its name.

Look forward to seeing your project develop.  And really, really want to see what sort of vehicles you come up with!     

Best of luck with your project. 

[Elk101]

At 15mm the level change between streetside and river wouldn't have to be much more than 25mm, would it? Along the lines of what has been said above you could use a single piece of something like 12mm ply (as a compromise between sturdiness and weight as you could go thicker but it'd obviously be heavier) as your three baseboards. If you framed each one out in 25mm deep timber edging, (perhaps with a centre cross piece too?) you could then either infill the frame in 25mm blue foam for lightness and the possibility to locally change levels, or you could top with a thinner mdf (heavier and you'd need to fix it down well, perhaps requiring more of a framework. The river dock tile looks like an L shape so you could frame out the L so that the frame is the basis of the dock wall on the two water based sides and the board is then textured for the river, as per the suggestions above. Just a thought.