New York, Vermont & Northern Rwy. (HOn3 coal line + HOn30 Quarry Line)

[deemery]

I really like the folded layers.  If you wanted that unconformity, the difference between the folded and the flat layers, you really need the flat layers to look sufficiently different that they were laid down at a different time than the folded layers.  (That's the definition of 'unconformity' - basically "part of the geological record is missing".  If you look at pictures of the Grand Canyon near the bottom, you can sort of see what I mean, where there's a significant difference between the layers of sandstone above and the quartzite(?) at the very bottom of the canyon.  

But of course, that's just my $.02, and with inflation it's not worth very much these days.  

dave

[Bernd]

Thanks Dave. Not to knowledgeable on strata other than seeing it in nature.

I think I'll make it straight all the way to the top and save the curved for some other location.

Back when I started the quarry line Bill Gill convinced me to put a bend in the strata on the backdrop. I started with this.



After Bill made his suggestion, I looked into making a "bendy" strata.



It works better if you have a larger area than I have in the section I'm doing now..



It turned out quite nice.





So, I think I'm going to go with straight on the short section I cut out. It'll look more plausible straight than curved in the short length section. I think it might have worked had I curved the sections up toward the wall ending (to the left).

Bernd

[deemery]

That long bendy section looks really good!    In general, though, I think you get either bendy stuff (i.e. the mountains) or relatively flat stuff.  One metaphor that works is to think about pushing a towel laying on the floor.  

But those flat sections don't have to be 'parallel to the deck', they're often tilted.  

dave

[Bernd]

Thanks Dave. I'll get it figured out.

Bernd

[PRR Modeler]

Bernd I think it looks pretty darn good.

[deemery]

Thanks Dave. I'll get it figured out.

Bernd

Yeah, just look at more photos of rock cliffs :-)  (Seriously, you do have a good eye for patterns, etc.)

dave

[Bernd]

Thanks Dave. I'll get it figured out.

Bernd

Yeah, just look at more photos of rock cliffs :-)  (Seriously, you do have a good eye for patterns, etc.)

dave

Thanks Dave. Much appreciated.

Bernd

[Pennman]

You have shown much patience...Grasshoppah !! More than I could muster up!
Onward..Very nice modeling.

Rich

[Bernd]

You have shown much patience...Grasshoppah !! More than I could muster up!
Onward..Very nice modeling.

Rich

Yes, Master. Patience is a virtue in model railroading.

Thanks Rich. I've finally got to the point if I don't think it looks right or feels right, it'll get changed.

Bernd

[Michael Hohn]

Uh-oh.  I'm in trouble now because I didn't explain clearly. 

What I had in mind was turning the whole rock face over so that the "bent" layers are on the bottom and the flat layers on top. 

Mike

[Bernd]

Uh-oh.  I'm in trouble now because I didn't explain clearly. 

What I had in mind was turning the whole rock face over so that the "bent" layers are on the bottom and the flat layers on top. 

Mike

Too late Mike. I cut the curved layers off and redid the top part with straight layers.

You're not in trouble. I like the way looks now. It was nagging me that something just didn't seem right. With your misunderstood comment it turned OK though. I like it now. Pictures to follow later.

Bernd

[Bernd]

I'm working on some procedures for making the quarry cars. I'm at probably needing around 40 quarry cars. The sides will be cut out of .020" thick brass and have groves cut where the sides bend to a 90° corner. I've used this method to mill flat pieces before, but it didn't work on thinner sheet brass due to the unevenness of the wooden sacrificial board used under the brass sheet. It was too uneven to begin with.



I figured that the MDF was flat enough for the first part. Not so. Note the areas that it cut through and where it didn't. Apparently, it wasn't flat enough plus the clamping method with the screws isn't ideal for material only .020" thick. It has a tendency to warp. Even a warp of .010" on a .020" thick material is detrimental to getting a good part. So, I "surfaced" (made flat) the top of the MDF with a surfacing cutter.



And as you can see that didn't solve the problem from the part marked "second piece" above.
 
Here's a better view of second piece cut and where it cut through.
This is the top view.



And the bottom side.



This is not going to work if I need 40 parts. I'll be making an aluminum jig to properly hold the pieces of .020" thick brass sheets.
 
I can save the second piece cut. I'll finish it by using a coping saw (fret saw) and file.

Why the accuracy needed? The cars are going to go in a rotary dumper yet to be designed and built. I figured I'd make a car first so I can get a better idea of the size I need to make the rotary dumper. Here's a picture of one I'm using as a templet. Found it on E-bay from Chyna.



 

I was able to use the second piece for the next process of making the sides. I used a piece of rock maple to make a fixture for soldering the one side together.



Test fitting the plastic car. Nice sliding fit.



Test of the folded brass shell.



Using two machinist clamps to hold it together for soldering.



If you're wondering how to make presession folds on something this small, I'll repost this photo. Notice the three extra lines. Those are engraved about .010" to .015" deep and will facilitate a good 90° bend. You can see the cutter with the orange ring in the upper right of the picture that was used to cut those grooves.



Next up will be designing a jig for cutting out those 38 other sides.

Until then.

Bernd

[deemery]

Two questions:  1.  Why not use a metal for the underlying flat surface?  2.  How are you attaching the thin brass?  Does that attachment method introduce any unevenness?

dave

[PRR Modeler]

Great start Bernd.

[Bernd]

Two questions:  1.  Why not use a metal for the underlying flat surface?  2.  How are you attaching the thin brass?  Does that attachment method introduce any unevenness?

dave

Dave,

The underlying surface will be a piece of 1/4" or thicker aluminum with a channel milled in it to contain a strip of brass with clamps on the sides. I'm going to lay out the full process as I go. This part is a "what not to do for a production run of 40 pieces."

Go back to the first picture in post #146 and you'll see at least three of the four screws with double washers holding the piece of brass down. Does not work very well for thin sheet metal. And yes it cause unevenness. With the soft MDF you'll indent where the screw holds down the part causing the sheet further away from the screw to buckle upwards.

Bernd