Replicating a concrete wall

[Wes R]

I hope i posted this in the right spot. I have shelving set up for my Coldwar and post apocalyptic props and I was wondering if anyone knew how to replicate concrete blocks as there is some space behind the shelves and i want to put a panel behind there to look like a concrete fallout shelter wall.
The gap is only a half inch so i don't have a whole lot of room. Any help is appreciated.

 

[Kyle138]

You could try some foam from a hobby or model shop, maybe smooth it out, and then hit it with some textured spray paint ( i've seen this before at the hardware store) Maybe it will work. Lol

 

[Sigma-LS]

And make sure to give it a good zap of brown wash too. Nothing says fake stone like uniform cleanness.

Also you could buy/borrow a cinderblock, make a small mold of 1 side, cast a thin block veneer in resin and glue to a panel x times to make a wall then paint. That I think would be most realistic. Bonus if you smear dust and aggregate into the cracks

I will say though that fake rock and concrete even done professionally will never hold up to any sort of close scrutiny.

 

[Wes R]

It figures i'm going to be 3 doors from a closed hobby shop tomorrow lol. Well we have plenty of cinder blocks here, i just need to get some RTV. This won't get very close looks as i never have visitors and there will be stuff behind it but i figure it would look better as a display, i even have a fallout shelter sign to put on it. I should just steal our cinder blocks and break the fronts off them lol.

 

[Wes R]

come to think of it if i had some of that RTV you just smooth over an item to make a quick cast of it i could slap it on the basement walls as they're cinderblock.

 

[themanwoaname]

you could get a foam sheet at homedepot and carve into it what you want. you could make the wall, cracks and hole to see the shelter and probably seal and paint it in a days work.

 

[Wes R]

I'd use lowes as my works there and i refuse to say no to an employee discount but that's not a bad idea. I had foam artboard here but its a pain to get the paper covering off of it.

 

[themanwoaname]

the paper covering might help for effect, like wall paper or propaganda posters of nuclear war tearing off or something.

 

[Wes R]

That's what i was thinking and funny you should mention it as i posted a question about that in the paper props area today. I do have a vintage Civil Defense booklet from back then too.

 

[themanwoaname]

the whole would be really awesome when its done, im very interested to watch it on the way to completion.

 

[TK648]

Flexible Foam Prop Cinder Blocks Used In Spider Man 3

Here is an idea from smooth-on, it show's how the cinder blocks in
spiderman 3 were made.

Flexible Foam Prop Cinder Blocks Used In Spider Man 3 | Smooth-On

You would not have to mold the entire block just the face of it.

 

[Wes R]

That's what i was thinking of. Sadly its gonna be 4 months before i can afford materials lol

 

[exoray]

Cinder Block A [VF-.030-HIPS-CinderBlock A-Hor] - $38.75 : VacuFormStore - VacuForm Panels, Brick, Rock, Stone, Slate, Siding, Roofing, Bamboo, etc.

“Recast” Cement Block PAS005 : Pulp Art Surface panels are made of 100% recycled cardboard and newspaper. Easy to install and very affordable. We currently offer brick, stone and cement block with many more to come.

 

[Wes R]

The 38.75 is a bit pricey but the other i am going to look into more.

 

[tommin]

You might want to look into floral foam. It's pretty cheap and might work out for what you are trying to do. Take a look at the following...

Working With Floral Foam:
DBA Guide to Working With Floral Foam by Pete Flynn

 

[propologist]

easiest and cheapest way would be to cut the blocks form out of a flat piece of blue foam and then mix sand with paint for the effect. Weather and there you go. If you need them 3D just make them out of that or foam core and do the same.
buying foam blocks is crazy if your short of money and time. Some people like to spend the money for no apparent reason.lol

 

[Wes R]

lol. Well the way this month is looking with medical stuff i may have to do it this winter when i'm not going anywhere. I think my budget for the next few months has died thanks to holidays and birthdays. For some reason everyone has to be born in october that i know.

 

[clonesix]

Do you want this to look like cinder block, or poured concrete? The two look different. Poured concrete, as in fallout shelters and basements, are poured against wooden forms, either plywood, or 1x6s. Hence, it retains the reverse impression of the form.


My thought is to get a 1/2 sheet of CDX plywood, mix up a batch of concrete an cover the pywood with the size you want. Add some wire mesh to the back side for reinforcement, and make yourself a 1/2" pannel.

Thoughts: Part of the look od a poured wall includes horizontal lines formed by using 1x6s. another thing that say "concrete" are the air pockets that are inevitable in pouring a heavy mix. Hence, they leave small divits in the wall.

Dont forget that concrete weighs 165 lbs per cubic foot. a 2'x4'x0.5" = 55lbs

 

[Wes R]

I was thinking of the old 50s shelters when most of what they adviced home shelters to be made of cinderblocks and dirt. I have the construction manual from civil defense someplace. i'll have to look it up now that i think about it.

 

[Darth Mawr]

Find sponge rubber if you can the size of your concrete block and use it like a giant stamp. paint your wall area the color of mortar then "stamp" your blocks in a slightly contrasting color.