Large Scale Central

Rock dynamite storage house build

Modeling
#1

On the Durango & Jasper we have a gold mine. It is inspired by this 1980’s HO layout by John Olsen:

So far we have the 2 level trestle roughly in place. Here’s a shot after the initial install of lighting within the mine entrance:

It seems like this mine needs a lot of details. I’m starting by adding a rock building to store dynamite, to be placed at the far left side of the above photo on a rock ledge. There will be wooden steps leading up to it from the upper trestle level. The building will be a simple rectangle with a single pitched roof of corrugated metal. It will be ostensibly built of rock (the same rock as the rest of the landscape) with a metal door.

I’m planning to build it using a technique of Ray Dunakin’s (I try to steal from the best), as in his 2 story house (link).

Ray built a form, put rock in the form, and mortar inside that. After removing the form, you end up with a building (there are more steps :-)).

So here’s my form (made out of foam board):

Here’s a wood door frame where the metal door will be. It will be mortared into the form and held in by rocks and mortar:

Some more bits of foam core were glued in place to hold the wood frame in the right spot so I can add the rocks around it:

And with the wood door frame in:

Next up is adding rocks and 1/4" hardware cloth for added strength in the mortar (as per Ray). Then mortar on the first wall, let it cure, turn 90 degrees and do a similar thing on the next wall and repeat.

I’ve never done this before so wish me luck! All my mistakes will end up here :slight_smile:

Cheers!

Jim Rowson 2023 Mik challenge build: Bank of Durango
Casey's Saloon on the Durango & Jasper
#2

Good start. I’ll follow this build.

#3

I put a layer or rocks in around the doorframe for the first wall. Wow, that was like (I imagine) building a ship in a bottle the hard way. Glad I have some bent tweezers. Sheesh!

I hope I don’t screw this rock layout up when I add the reinforcement metal!

I also haven’t quite figured out how to add rock up the side walls to the level of the plan for mortar (about 1/2"). Maybe the metal reinforcement can hold the rocks in place…

Any suggestions (before I get frustrated and throw this across the garage) is appreciated.

Cheers!

#4

Jim, I’d place rocks against the side wall high enough to be above your planned cement depth. Use of wire will help reinforce, and again bend it to go up the side walls a bit farther then you plan the cement depth to be. (https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-cool.gif)

#5

Following.

#6

building from the inside out - interesting idea.

#7

Ray Dunakin? used this way to build one of his first structures. The build should still be documented in the archives here (https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-cool.gif)

#8

I posted a [link] to Ray’s website where he documents the rock technique, here it is on this site [link] (a bit more conversational here).

Meanwhile, I’m guessing I did’t get the mortar to be liquid enough on the first wall. No way to tell except to finish this thing and see. I went more liquid on the second wall. Here are some pictures:

And the 2nd wall is started (mortar is on, setting):

Messy fun!

#9

#10

Not atomics, Rooster, just TNT :slight_smile:

#11

Still slobbering over the thought …and will await progress pics

#12

Keep an eye peeled.

I’ll post the progress and unveiling after all the walls are formed. I hope it isn’t too disappointing!

#13

K-9 and Rooster will await future postings

#14

Cool project! The mortar needs to be fairly thin – but not too runny. Hard to describe, but you want it thin enough to flow down into the gaps between the rocks, but not so runny that it gets completely under them. That may happen to some extent anyway, of course, but you want to limit it.

If you do have places where the mortar isn’t between the rocks enough, there are ways to fix that later.

#15

Jim,

When I did mine, I poured each wall separately. I left the “rebar” (hardware cloth) long enough to allow it to fasten to a wall on either side.

After I de-molded each wall, I scraped the cement off and let it dry…

Oh yeah, it will look like this when first out of the mold…which is why you want to scrape the cement off the rocks.

a super-form to hold the ends straight while I poured a side. I also added some additional bracing to reduce any flexing. Below, you can see that I have my two finished “ends” and will be pouring the side (at the bottom).

I used a toothbrush to clean the rocks after each pour. You should probably have a used one. (https://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-foot-in-mouth.gif)

Jim Rowson 2023 Mik challenge build: Bank of Durango
#16

Thanks for the help!

Ray: I will no doubt need advice about how to fix too-thick mortar. in your previous writings it appears I should use glue with sprinkled on dry mortar…

Bruce: that is massive! At least compared to what I am doing. Thanks for those pics, helps me anticipate what is to come.

sadly, I need to go to work so this will have to wait for next weekend…

#17

The unwrapping!

I am pretty sure I was too stiff on virtually all of the mortar (maybe all of it as it doesn’t really look like much of it got through the rocks).

Lots of rocks came off:

Here are the walls:

So what do people think? Fixable? Or should I start over?

I am leaning toward starting over. I should check this out where it is supposed to go to see how it looks, etc. That may determine whether I need to redo it just because the size is wrong.

[edited for a typo]

#18

Here is where I am imagining the building to go:

My gut is telling me that I should maybe rethink this and see if I can find a way to build it into a cave in the wall, rather than as a standalone building. Or I could keep the building and stack rocks around it to make it look more like it was built into the mountain a bit more.

Any comments from the august panel of experts?

#19

Rocks are rearranged, wdyt?

#20

Jim Rowson said:

My gut is telling me that I should maybe rethink this and see if I can find a way to build it into a cave in the wall, rather than as a standalone building. Or I could keep the building and stack rocks around it to make it look more like it was built into the mountain a bit more.

Any comments from the august panel of experts?

Since it’s not August yet (I checked my calendar twice as suggested) I would like to request you save my response until Wednesday. However if you peeked before August here is what I think.

“Slap some rafters and a tin roof on it with a very secure door then call it done as it looks good to me”!

It’s a dynamite shack which I know little about in that era however why would they want ALL the dynamite close to the cave? It would need to be accessible and outside away from the cave they are blowing up? Right?

This post has been edited by :Rooster