Dioramas: Buildings & Ruins
Ruined buildings and city scenes.
Hosted by Darren Baker
help on plaster buildings
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Ohio, United States
Joined: February 05, 2004
KitMaker: 545 posts
Armorama: 295 posts
Posted: Tuesday, February 10, 2004 - 06:43 AM UTC
I've tried to scratch build some buildings out of plaster of paris. Needless to say, it's very messy, and when it drys it's practically impossible to work with it without breaking.

I've been able to work it as a great medium for streets, and of course lots of rubble...but, if anyone has advice on how to make it into an actual building, I'd be quite grateful!

** I've tried to build it with a wooden frame (small craft sticks that keep the plaster in the basic shape, and out of the window openings) and that's worked until I take it off the countertop, or tried to detail it.
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Michigan, United States
Joined: December 11, 2003
KitMaker: 5,409 posts
Armorama: 3,777 posts
Posted: Tuesday, February 10, 2004 - 07:32 AM UTC
I normally don't use plaster of paris to build a wall. I make the building out of thin wood boards and just use the plaster to skim a coat over it. Of course this technique is not used for brick buildings because once you start carving the plaster scraps off.

I have never tried it but since I do a lot of home reovations I have found that dry wall spackle might be good. It is much more durable than plaster of paris.
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California, United States
Joined: May 26, 2003
KitMaker: 1,255 posts
Armorama: 485 posts
Posted: Tuesday, February 10, 2004 - 11:12 AM UTC
Basics of Building Construction

Check out this article and see if it helps. Instead of Plaster of Paris try using Durham's Water Putty. Shape easy working, but much easier to work once it dries and harden.
Good Luck


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Donegal, Ireland
Joined: May 14, 2002
KitMaker: 9,763 posts
Armorama: 7,444 posts
Posted: Tuesday, February 10, 2004 - 11:57 AM UTC
Hi Steve-o.
I believe its something to do with the quality of the plaster you are using. Where I buy the stuff it comes in two different grades and one dries harder than the other. Its called hobby "gips" here in sweden and dries in about half an hour. (the same stuff comes in childrens figure molding).
I buy the stuff that dries harder and cast it the same way .... make a square frame with balsa or similar. When mixing in the water ... I pre-mix the water with white glue as well to give it a better bonding. I let it dry for at least 2 days before touching it again. I cut and carve normally. I keep my walls pretty thick ... at least 1cm, and always work on a flat surface. I bought cheap scribing tools from the hobby shop and scribe the cuts more than half-way before trying to cut with a hobby saw. If you cut out a window, drill small holes before drilling big holes. I have had o problems yet, but I only use this method for ruins. If I wanted a more detailed building I would build it from balsa and cork and cover it in spackel as mentioned above. Below is a cast wall Im working on at the moment made this way (1/16 scale dio).
let me know if you have any other questions.

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North Carolina, United States
Joined: February 22, 2002
KitMaker: 11,718 posts
Armorama: 7,138 posts
Posted: Tuesday, February 10, 2004 - 02:01 PM UTC
All good advice so far. Here are my two cents - I use Woodland scenics Hydrocast. I build a small frame on a tile and seal it with masking tape.

Here is the results
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Washington, United States
Joined: September 28, 2003
KitMaker: 261 posts
Armorama: 0 posts
Posted: Tuesday, February 10, 2004 - 02:42 PM UTC
If in fact you still use plaster, one thing you may want to try is after pouring half of the plaster in the mold, place a piece of window screen material on top of the first half and pour the balance of the plaster in. You can cut out the openings for doors and windows before you place it into the plaster. When it dries it will add additional rigidity to the piece.

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Kikladhes, Greece / Ελλάδα
Joined: September 30, 2003
KitMaker: 6,871 posts
Armorama: 2,071 posts
Posted: Tuesday, February 10, 2004 - 06:07 PM UTC
Well i have been using the here called Atrist's white plaster with no problems. I build wooden frames in a thin wooden base covered with tin foils also covered with vaseline for easy take off. i plan the dimensions and frame them make the plaster mix with a lil more water to work it easy and pour. usin small blocks of wood or matchboxes in predesigned places you get the openings for doors and windows (thiugh saometimes the need for a window comes after and i have to carv it) and you pour . i let dry over 2 days in normal room temperature and then one day in more hot to take all moisture out and then i start to work. Dont do hard movements and handlings cause its easy breakable . Other than this i work it with some dental tools for scribing and also with old xacto blades . I use normal sand paper to shape and form and also the dremel in low speeds to drill or do other damages and carving. The following plaster building for the vietnam dio plus a wall for the same dio, were molded in one evening , and after 3 days they were ready to work on them. Plaster is a good material to work with just needs some experimentation
hope i helped a lil

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England - North West, United Kingdom
Joined: November 13, 2003
KitMaker: 2,240 posts
Armorama: 808 posts
Posted: Tuesday, February 10, 2004 - 10:37 PM UTC
That's a fine bunch of pics. Inspirational all.
But Plasticbottle...your ruined building has got me sniffling with nostalgia. Just like the old ruined terraced houses I used to play in as a kid...I can almost smell the damp gypsum and coal dust and the rotting wood. Strange what can trigger the old weepies.

Has anyone tried adding fibre of some sort to the PoP? Or reinforcing with a mesh?
Ignorance of the innocent?

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Iowa, United States
Joined: October 23, 2003
KitMaker: 884 posts
Armorama: 609 posts
Posted: Wednesday, February 11, 2004 - 04:09 AM UTC
I agree with the use of the woodland senics hydracal as it is much stronger, two others would be dental plaster, and molding plaster (the stuff used to do molding in houses at the turn of the century, still available at most large home improvemnet places, Lowes, Home depot). I have used all three products and they all preform pretty well. I am currently using the molding plaster for my Carentan project, and have only had a few problems, mostly corners chipping. My thick plaster I pour 5/16" as the thickness does help. I have never tried the screen idea that will be a new one for me to try. I would bet you would have better luck with any of the 3 products mentioned.
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Indiana, United States
Joined: October 16, 2002
KitMaker: 5,272 posts
Armorama: 2,844 posts
Posted: Wednesday, February 11, 2004 - 04:17 AM UTC
I pour walls out of hyrocal as well. I pour mine on an aluminum plate with a wooden frame around it. You may try a new cookie sheet. Hit it with some Pam and pour in a lay of plaster. After it dries, you should be able to flex the cookie sheet enough to "pop" out your slab.

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Ohio, United States
Joined: February 05, 2004
KitMaker: 545 posts
Armorama: 295 posts
Posted: Friday, February 20, 2004 - 04:26 AM UTC
Sorry it's been so long since I replies and thanked everyone, it's been crazy over here! But, thank you very much for the suggestions! Now I know I'll get some of these built up and finish my slew of dios waiting for buildings.

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Quebec, Canada
Joined: January 01, 2004
KitMaker: 7,600 posts
Armorama: 6,110 posts
Posted: Saturday, February 21, 2004 - 02:16 PM UTC
I also use hydrocal as it is stronger and lighter than plaster. For walls of specific size and shape I make a mold with Lego bricks on their flat yellow base sections. Then I take some embossed plastic sheet with the desired brick or stone pattern on it, cut it to the size of the mold ( it should fit VERY snuggly without warping or bending into the bottom of the mold - the height of the mold could be 2 - 3 bricks high, depending on the thickness of the walls you want to make) and place it FACE DOWN in the bottom of the mold. If you want to add windows or doors, make them either from plasic scrap glued to the surface of the embossed sheet to form a dam against the hydrocal, or use balsa 'beams and planks' for a more rustic look. The wooden pieces will adhere to the hydocal and you will have your door and window frames allready installed. Pour your mixture in making sure that it flows into all the corners and cracks. Let it dry overnight to be really sure. To remove the casting from the Lego mold just disassemble the mold brick by brick and then carefully pop the embossed sheet from the hydocal surface. You should then have a wall surface with the brick/stone pattern and window and door openings. Sometimes a bit of cleanup is neccessary around edges due to inevitable leakage. If the wall should crack, all is not lost, just glue it back together with carpeters glue. Usually the crack will disappear, and if it doesn't, will just look like intentional damage.