Large Scale Central

Bridges/shelves

Modeling Technical Modeling
#1
I had this idea a while back for storage shelves: instead of just a flat board, I’m going to make bridge sections that will mount to the wall with an L-bracket.  Since we moved 3 years ago, I don’t have a layout any more.  I plan to start one at some point, but for now I want somewhere to display the cars I’ve built.
 
Here’s the prototype I picked.  A former NC&STL bridge, about two miles from my house:

 
 
Here are how the stanchions came out.  I drew them in Sketchup, and had one made in brass (by Shapeways).  I sent that off to be used as a pattern to cast more.  The left-most (shiny) one in the photo is the pattern:
 
#2

Interesting railings. 3D printing is proving quite useful. The railing stringers, for lack of a better word coming to mind, appear to be 2 or 3 layers - is that just an illusion from a molded groov?e.

#3

Cut it out … your shelves are going to be more detailed than most of our layouts!

#4

I think what you’re seeing in the railing is a gap left from the process of forming a rectangular tube from flat stock. I suspect there is a bolt that runs all the way through the stanchion, and has a nut and washer to hold the railing in place. Probably for the sake of heat expansion. If that’s not a satisfactory explanation, maybe someone else can help me make up one.

#5

Here’s my construction guess for the slats.

To make them curved they folded the steel over on itself. Looking at the far side there is no groove. So I’m guessing the fold is done to set the curve.

What do I win? (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-laughing.gif)

John

#6

I got started on the patterns for the girders today. Actually, I re-started on them, as I was not happy with my first attempt.

First I printed out a 1:29 scale line drawing to use as a pattern for making rivets:
(http://burlrice.com/_LS_Bridges/001.jpg)

After the rivets were all stamped, I scribed the edges. This is where I messed up on the first try, and got them off-center.

(http://burlrice.com/_LS_Bridges/002.jpg)

Then I marked guidelines to glue them to. I’m using 1/4" foam-core board as the core. I want it thick, to I have plenty of room to sink screws in the castings later. So, I doubled up the foam-core board.

(http://burlrice.com/_LS_Bridges/003.jpg)

After the top & bottom chords were glued on, I used the paper template to mark where the ribs will go:

(http://burlrice.com/_LS_Bridges/004.jpg)

Here’s where I left it for tonight, with the shims for the ribs glued in place:

(http://burlrice.com/_LS_Bridges/005.jpg)

#7

So, um, are you counting them there rivets?

#8

I tried, but I ran out of fingers and toes.

#9

Today’s progress:

I made the vertical ribs. I cut several .030" x .188" strips, and taped them together. I drew reference lines, and stamped the rivets all in one session:

(http://burlrice.com/_LS_Bridges/006.jpg)

I removed the tape, and glued them to the main body:

(http://burlrice.com/_LS_Bridges/007.jpg)

Then I glued on some .060 x .125" for the standing part of the rib:

(http://burlrice.com/_LS_Bridges/008.jpg)

I left the ends long. I’ll let this sit over night, and trim them to length tomorrow.

#10

Are you using the NWSL riveter for making the rivets? Or something else?

#11

I see that I am not the only one who has issues hitting the lines dead on with a rivet embosser.

#12

The prototype isn’t evenly spaced either, so I don’t feel so bad about it.

Yes, its a NWSL riveter.

#13

So, might these be items that will be “For Sale” at some future date? I’m thinking I could use a few of these to fix and replace a certain bridge that a puppy has chewed on.

#14

I’ll have to see how much resin it takes before I know if it would be feasible to sell. I made them pretty thick.

#15

The thicker the better for outdoor use. I’ll keep watching.

#16

The pattern is now finished, primed & ready to make a mold of:

#17

Looking good!!

#18

Here are my first good castings. I will make another mold of these so I can pour two at a time.

(http://burlrice.com/_LS_Bridges/010.jpg)

#19

Looks great, as usual… :slight_smile:

#20

Andy Clarke said:

Looks great, as usual… :slight_smile:

Yes it does. (But what does Andy know? (http://www.largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-foot-in-mouth.gif))