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DRW-FJ40
09-14-2012, 05:47 AM
Maybe I shouldn't be posting this yet as I don't know how to do it but I intend to learn and here is my plan:

I'm going to design a series of templates in CAD for modular "cut stone" building blocks. I'll make them out of wood since it is a medium I'm comfortable working with and have the tools to work with and it's fairly inexpensive.

Then I'll make a mold of them and cast building blocks in concrete. My building and bridge designs will all incorporate the standard sizes and configurations that I've created the blocks in.

Once I have a collection of concrete "cut stone" blocks I can build anything in scale cut stone.

I'm thinking a medieval castle with a stone bridge so I can drive through in my TF2 and rescue a fair maiden princess in distress from... something... I'm not sure what yet… we do have a dinosaur problem around here… but that’s another story.

DRW-FJ40
09-14-2012, 06:41 AM
Step 1, will be coming up with ideas. For my project, a castle, I am going to get the DK castle book. DK series often use models for their book pictures & are a good series of books to get ideas from on a range of topics.

Step 2, once I have a rough idea of what I'm going to build, is to play around with the idea in CAD & come up with my modular building block dimensions. The intention is to come up with standard building block dimensions that can be assembled in a variety of ways so that I'm not custom crafting each cut stone. Think building with Legos.

Step 3, Create the blocks in wood.

Step 4, Make a mold of the blocks

Step 5, Cast concrete building blocks from the molds.

I'll get to these in more detail when I get to them.

Once I get the blocks cast and ready to build, I'll start a build thread on my course thread. That is, unless Mr. Unglewd makes a stone castle section on the forum in the interim.

But my intention for posting it here is so that anyone can follow behind & make modular concrete pieces to build anything from buildings to bridges to something I haven't thought of yet, in their outdoor scale course/diorama.

DRW-FJ40
09-14-2012, 06:53 AM
I'm a tad out of sequence here but I wanted to research step 4 first since I haven't made molds at all before.

I figured I could get some good info on resin casting here but I turned to the people at Smooth-on to answer my questions about this project specially, they were extremely knowledgeable & deal with all kinds of molding and casting materials and methods from a sculpture/artistic perspective (A quick Google search and you will realize that concrete casting and molding has a lot of industrial applications).

After talking with them about this project, I'm going to use VytaFlex® Urethane Rubber with a shore A hardness factor of 40. The latter is an index of how flexible the cured mold will be. Number 10 is very soft and easy to pull off of intricate models. 60 is fairly rigid & stands on its own well but is difficult to get detailed models to release from the mold.

Think ice cube tray. It's a very rigid mold so you just set it on the counter, pour water in & the frozen ice cubes fall right out because they are not intricate in shape, in fact, they are beveled on the edges to make them release easier from the mold because their shape is not critical... well at least to the masses. I personally have a lot of opinions relative to ice cube shape but due to restrictions on lewd and inappropriate comments on this forum, I can’t go into that here.

Here is a link to Smooth-on's VytaFlex® Urethane Rubber mold products (http://www.smooth-on.com/Urethane-Rubber-an/c6_1117_1142/index.html).

imthatguy
09-14-2012, 09:11 AM
Once you figure this out, I'd like to order a couple hundred.

DRW-FJ40
09-14-2012, 09:32 AM
Sorry can't sell pre-molded rocks to those who profess to scratch build.

crawlin
09-15-2012, 05:26 AM
He wants blocks not rocks lol

Honger
09-16-2012, 12:54 AM
Forgive my intrusion... but this sounds too cool not to brainstorm along with you.

How big are you thinking these blocks will be? Also, I think you are making this too hard... why not just build the molds out of wood? Seems like you'll save a step.

DRW-FJ40
09-17-2012, 06:34 AM
He wants blocks not rocks lol

I just shipped 3 tons of rock to Matt's address but since he scratch builds his own rock, I figured he would prefer to carve his own blocks from the rock.

P.S. It's C.O.D. should be there sometime today. I cut him a break but shipping seemed really high.


Forgive my intrusion... but this sounds too cool not to brainstorm along with you.

How big are you thinking these blocks will be? Also, I think you are making this too hard... why not just build the molds out of wood? Seems like you'll save a step.

Intrusion & brainstorming welcome.

They will very in size but roughly, the basic block would be like cutting a 1.5" section of 2x4 off. Also, some will be thin for veneer. so I could make some sort of flat surface and then lay thin stone block on top, i.e. roads, courtyard, etc. I want to put detail on the inside but if you cover it, then you can't see the detail so I'm thinking a mixture of open courtyards, some towers, a road incorporated into it with a stone bridge.

The main reason for making the urethane molds would be detail. since the original block will be a plug, I can carve "cracks in rock" I want to make a circular pattern in the courtyard with a large (6") diameter centerpiece stone with a compass rose & orient it in the rock garden pointing North. So once I have a basic wood block, I can carve cracks or add styrene for raised detail. It won't matter if I mix materials because it's just a plug. I can make a couple variations of the cracks & some plain ones too so it doesn't look like all the blocks have the exact same crack.

If you put that level of detail into a rigid mold, it's next to impossible to get the blocks out. plus, some of the blocks will have a fairly intricate shape, like those for tying bridge arches into the support columns.

DRW-FJ40
09-28-2012, 12:57 PM
I've drawn out my stone block templates in CAD. They look like this right now:

http://i1136.photobucket.com/albums/n493/DRW-FJ40/Castle/StoneBlock.jpg

The curved block will be for a central courtyard and I just use the first few diameters to make tower bases. I have a basic building block of 1.5 x 3" so I can make 3" x 3" bridge columns that will fit to the bridge arch support.

I may make a smaller block for road surface. I want to have roads & bridges incorporated into this so I can drive through it.

Court yard & curved block will fit like this:

http://i1136.photobucket.com/albums/n493/DRW-FJ40/Castle/castlecourtyard.jpg

While I was at it, I made some tombstone templates. not sure yet if I'll do these in resin or concrete.

http://i1136.photobucket.com/albums/n493/DRW-FJ40/Castle/Tombstones.jpg

DRW-FJ40
10-04-2012, 06:43 PM
Slight change in plans. Styrene makes more sense. It will be easier than wood to carve cracks, etc. & I won't have to work to sand the grain out of the finish.

UNGLEWD
10-05-2012, 05:30 AM
For which pieces?
The designs are looking cool... I'm guessing there's going to be a Halloween scene coming up in that park of yours!

DRW-FJ40
10-05-2012, 10:29 AM
I'm thinking all of them. Wood would have been cheeper but I think I'll end up spending significantly more time preping the surface for molding. Since they will be rock, I'll need to get all the grain out & doable but not necessary.

And yes, on the Halloween theme. I have some ideas for Christmas too. I don't invision having it ready for that till next year. I want to get the blocks done, molds made soon so I can leisurely cast blocks all winter. Unlike other things I've made for the park, this will have to be built "on site" so hopefully, by spring thaw, I'll have a collection of building blocks.

pardonmyn00b
10-05-2012, 05:22 PM
I'm waiting for your local news to do a human interest story on you. "This is Doug, he likes Jeeps and castles. Let's take a look at his little world."

crawlin
10-06-2012, 04:40 PM
Hey I'm a Doug I like jeeps and castles lol

DRW-FJ40
10-18-2012, 07:31 PM
I have to keep up with these threads & all the slanderous blasphemy and goings on. Jeeps???… Castles yes but…

You know someone told me FJ stands for foreign jeep?

The world needs more Dougs, keep up the good work crawlin, and buy a toyoter!

Just another roadside attraction... Man, I should write a book.

pardonmyn00b
10-19-2012, 04:19 AM
I prefer Fake Jeep. Not to be confused with the fake Jeep imthatguy has. That's a different kind. I'd read your book.

DRW-FJ40
10-19-2012, 04:39 AM
I prefer Fake Jeep. Not to be confused with the fake Jeep imthatguy has. That's a different kind. I'd read your book.

your up early.

pardonmyn00b
10-19-2012, 06:03 AM
your up early.

I was already at work. As you can tell I'm very busy

crawlin
10-19-2012, 03:50 PM
Well that's funny cause I'm doing a yotie it's my mr T f2 once the jeerp is done ill be on it

sgl
05-01-2013, 06:59 PM
While I was at it, I made some tombstone templates. not sure yet if I'll do these in resin or concrete.

http://i1136.photobucket.com/albums/n493/DRW-FJ40/Castle/Tombstones.jpg[/QUOTE]

Am I right in assuming that there are no winners names on those tombstones?