hello all,

I am trying to construct a diorama with a Roman Building. I cut it out of FOAM BOARD, then was told to use everything from Plumbers Putty, Painters Putty, and plaster, to air drying clay to make the parts of the house that dont fit perfectly together smoother, to fill gaps, etc. The plumbers putty and painters putty never dries so is impractical ( I waited a week for it to dry and it did not), then I tried plaster but it cracks and falls out as does the air drying clay (this shrinks and then cracks and than falls off - I used both Crayola and Amaco's Stonex Self Hardening Clay). I just tried Lightweight spackling, but I was told to use this OVER the clay. I am following both my teachers directions (he suggested the plumbers putty that does not dry) as well as a book called Lets Build Diorama by Laszlo Adoba. His suggestion to use the clay is not working as it shrinks and cracks over the foam board frame. Does anyone have any suggestions? THANK YOU!

use something else for your frame. you may want to try foam board. or you can use florists foam.

Hi - thank you for the reply. Yes, I am using Foam Board (that is what I meant). It doesnt seem to matter wether it is covered with paper or not - i tried it both ways.

Can you insert some metal pins for the clay or plaster to grab hold of?

David, two very important parts are missing from your ingredients. Add a bit of liquid dish soap and a good amount of good white glue when you mix up your plaster. The soap helps it spread into any nooks and the glue helps hold it together. Too much glue will make it hard to cut, drill or change around so be careful. You might add your paint to this as you mix so the color will be even and any chips later won't show up. With most (boards) when you build up clay or plaster, the surface must be rough for the stuff to grab on to or it will mostly dry and peal away. If you use foam board, a few spaced dimples will help hold it together, or toothpicks for wood. If you are using plaster type buildings I recomend Aleenes super thick white glue. It holds great and any excess can be scrap/cut off. Hope this helps some.

Any chance of a picture of the building? It would really help us to answer.

The plaster with the added ingredients Bob mentions should do the trick. How big are the gaps and how solid is the building. If the gaps are really big then it might be easier to redo that section. If they aren't very big and the walls are flat then you could possibly paper over them using news paper and white glue.

I would also recommend looking at the work of Carlos Elias who posts here as Blockhaus

Hi Everyone - Thank you so much for the feedback. Yes, the gaps are pretty big - well they are at the top of the building where the roof line meets the wall - I can get photos up. I will try placing the glue on the foam core, I also bought tape that has the wire mesh on it for use with Spackle and Stucco - to make it stick. I did not tear in holes nor roughed it up. I will try that as well as the glue. I am using CLAY, so I cant mix glue into it, but I did read that I need glue on the surface and to rough it up. Does it matter wether or not how thick the clay is I place on? Ive been making it pretty thin, so as not to change the dimensions of the wall, I apply the clay at about 1/8" thick or less.

Thank you!

I've never used clay as a filler because as you say it shrinks. I would use strips of foamcore board to fill the gap and then plaster. If you don't have plaster then use crushed dried clay mixed with white glue and build it up in layers.

Thank you so much. I am taking photos and will post as I go along. An entire part of one wall just collapsed, it got so wet with the clay I kept putting on (three times because it kept shrinking), and then the glue, then the clay again. It got wet, and caved in (there was a layer of paper on the foam board) - I had to cut a new wall! I am trying several of these methods all on the same model, to see as I go which works best. THANK YOU ALL!

David

Hi All - Here are some photos for the diorama I am currently building. This is the BASE model, before applying any siding or finishing up the details. This is the skeletal structure. The model is a ROMAN HOUSE - very generic. I did use Villa San Marco in Stabiae Italy as a guide for this prototype. My class at Cornell University is currently doing research and work in the area on ancient Roman Gardens. I am posting these photos in hopes they will also help another newbie modeller as I.