First CN locomotive on the new track hauling a real load of Nova Scotia coal. This is the end of this project! Thanks for your interest.
Final ballast laid plus temporary track and some Scenic Cement. A little tidying up still to do with a fine brush and sponge. Now I can say this railbed is an HO scale replica built to the Canadian National Engineering Specifications for Industrial Tracks, produced by the CN Office of Chief Engineer Structures, Design and Construction, Revision date November 15, 2015.
I have removed the L-blocks and took this closeup before filling in the final ballast that goes under the track. The L-blocks did a nice job of supporting the shoulders while they dried.
OldSchoolScratchbuilder richhotrain Did you fabricate these aluminum blocks yourself, specifically for this project? Rich No. You can buy them at any stained glass hobby shop or probably online. They are called Layout Block System and are made by Morton Glass Works, Inc in Morton, Illinois. Comes with the pins.
richhotrain Did you fabricate these aluminum blocks yourself, specifically for this project? Rich
Did you fabricate these aluminum blocks yourself, specifically for this project?
Rich
Alton Junction
OldSchoolScratchbuilder The spacings between the block walls guarantee the correct horizontal dimensions. The height of the block walls provide a vertical ruler in the third dimension and the blocks also act as temporary retaining walls while the four vertical 2:1 shoulders harden with the cement so they can stand on their own. Same way they make sidewalks and curbs. This is a 3D build.
The spacings between the block walls guarantee the correct horizontal dimensions. The height of the block walls provide a vertical ruler in the third dimension and the blocks also act as temporary retaining walls while the four vertical 2:1 shoulders harden with the cement so they can stand on their own. Same way they make sidewalks and curbs. This is a 3D build.
Also, an interceptor ditch cannot be built until my vertical scenery contours are built - also not part of this thread.
So I'm performing music downtown nightclubs tonight so you won't hear from me until tomorrow.
Tomorrow, when the Grade 2 slopes are dry, I remove the blocks and add a 2.6 mm level Grade 2 ballast between the two shoulders I just built and this prototype model is complete. The tracks are the only thing left to install but that is not part of this build as I mentioned previously.
One last comment about the height of the level ballast. Since the blocks will not be in place when I put the ballast down, I will know I have built up the ballast to 2.6 mm because I will be designing 7"x9" cross-sectional ties. Everything below depends on everything above.
The spacings between the block walls guarantee the correct horizontal dimensions. The height of the block walls provides a vertical ruler in the third dimension and the blocks also act as temporary retaining walls while the four vertical 2:1 shoulders harden with the cement so they can stand on their own. Same way they make sidewalks and curbs. This is a 3D build.
The blocks hold up the 2:1 slopes in both cases. They are also key to getting the heights right. Nothing is being held down! You need to look at the CN drawing online.
I don't get all the pinned down aluminum blocks. What's up with that? Why does the sub-ballast need to be held down at all?
Section 3: Ballast
Six aluminum blocks are pinned on the top of the sub-ballast leaving the standard tie length between their outside vertical surfaces. A finer Grade 2 shale ballast is applied to the outside surfaces of the blocks following the slopes and dimensions in the CN drawing. Another spray of Scenic Cement and tomorrow I'll finish up the inside ballast.
Sub-ballast is now finished. I removed the L-blocks and the shoulders remained in place as I had hoped. Filled the inside with more Grade 3 shale sub-ballast (I make my own at no cost) and shaped the gentle 40:1 slope with a small block of wood. Another Scenic Cement spray down and let it dry. I may be able to start the ballast section later today.
Section 2: Sub-ballast
Thin layer of sandstone dried very quickly so I was able to start the sub-ballast. Six aluminum L-blocks (stained glass window supports) were pinned down with their vertical outside faces separated by the CN 8.4 cm spec. The 2:1 slopes (30-degree up angle) were filled and shaped up to a 3.5 mm height on the blocks with my processed Grade 3 shale particles from Walton, Nova Scotia. Finally, the outside shale slopes were sprayed with Scenic Cement. Tomorrow I'll be able to fill in the remainder of the sub-ballast. I am liking the railbed so far.
A very good article on curved track and prototype curves was written by Bob Cushman, "Curved Trackwork," Model Railroader, Vol. 23(10), October 1956, pp. 54-57.
Subgrade on the demo is complete. Used approximately 9.9 cm width and 1.2 mm depth at the outer edges. Applied processed sandstone particles from Cape Blomidon, pressed the slope with the heavy antique iron, checked the slopes with a level periodically, and finally a gentle spray of Scenic Cement. Will let this subgrade dry over night. Tomorrow I will start the sub-ballast section.
On a scrap piece of foam I can easily press the subgrade slope with an antique iron. The initial problem I had was friction between the iron and the foam - foam squeeks woke my husky up. A little dirt (processed sandstone from Cape Blomidon) and problem solved. I'll use this technique on my demonstrator.
In the middle of the night I woke up with an easy solution for making the gentle slopes of the subgrade. One of my wife's heavy antique irons. Pulled out a spare piece of foam and the weight of that heavy iron made it easy to push into the foam. Will use it on the 18" demo track today.
7j43k OldSchoolScratchbuilder I have given up on posting anything about my layout because of all the criticisms... You have an interesting and unusual approach to model railroading. I have seen not so much criticism as questioning. Either way, you have put yourself very much out in front of us. You should not be surprised by either criticism or questioning. If either of these threaten you, you may withdraw. Ed
OldSchoolScratchbuilder I have given up on posting anything about my layout because of all the criticisms...
I have given up on posting anything about my layout because of all the criticisms...
You have an interesting and unusual approach to model railroading. I have seen not so much criticism as questioning. Either way, you have put yourself very much out in front of us. You should not be surprised by either criticism or questioning. If either of these threaten you, you may withdraw.
Ed
Ed, your questions here are not criticisms just off topic. My layout posts in the layout forum was another matter. I am building an 18" demo here and there is no layout. So the answer to your question about 4.2 is that I do not have a curve on my 18" demo.
7j43k Yes, you state the obvious. And I do still look forward to how you handle 4.2 of the CN specifications.
Yes, you state the obvious.
And I do still look forward to how you handle 4.2 of the CN specifications.
You'll be waiting until late summer at the earliest. I am working on Section 3 for this small but complex demonstrator. There are no curves. After the earthwork, I add straight track and ties, wire the demonstrator, build the automated hopper loader, add ground cover, elevation contours, buildings, pavement, and lots more before I get back to my layout. The demonstrator is not covered here only the straight track bed.
I have given up on posting anything about my layout because of all the criticisms so you'll only be seeing small bits of my work at a time. That initial layout work is in the layout forum if you were not aware and I have stopped posting there.
OldSchoolScratchbuilder 7j43k I see that CN requires a maximum curvature of 9 degrees on industrial trackage. That would be 88" for an HO model. I look forward to how you handle that. This thread is about the CN railbed cross section detail (one engineering drawing). Has nothing to do with main lines, curves...
7j43k I see that CN requires a maximum curvature of 9 degrees on industrial trackage. That would be 88" for an HO model. I look forward to how you handle that.
I see that CN requires a maximum curvature of 9 degrees on industrial trackage. That would be 88" for an HO model. I look forward to how you handle that.
This thread is about the CN railbed cross section detail (one engineering drawing). Has nothing to do with main lines, curves...
Here is an alternative to understanding real track beds. https://m.youtube.com/watch?v=78sWxnY07c8
This thread is about the CN railbed cross section detail (one engineering drawing). Has nothing to do with main lines, curves, rails, crossties, level crossings, rail yards, hills, bridges, bumpers, switches, compression schemes or anything else. One CN drawing at a time so if you have a question on that drawing, look it up if you haven't already, I'll have an immediate answer that is appropriate to this thread. I will be finished this thread in a few days.
This is more real to ME than buying a piece of cork from the hobby shop and gluing it on my foam.
If you see a mistake in my calculations I'd like to know that.
7j43k I see that CN requires a maximum curvature of 9 degrees on industrial trackage. That would be 88" for an HO model. I look forward to how you handle that. Ed
Let me give you an example. On part of my layout, I model Dearborn Station in downtown Chicago. From Polk Street on the north to Roosevelt Road on the south is 4 city blocks, or 1/2 mile, or 2,640 feet. That is 30.3 feet in HO scale. From State Street on the east to Clark Street on the west is 3 blocks or 1980 feet which is 22.75 feet in HO scale. But, I only had a 12 foot x 8 foot area to work with.
So, you are going to need to take that consideration into account.
One additional note on the HO 1.2 mm depth. This only happens if the company engineer uses the CN minimum slope of 40:1. Any other slope choice reduces the 1.2 mm depth.
richhotrain Still curious, though, how long will your mainline be?
Still curious, though, how long will your mainline be?
Calculations complete. In HO scale the top of the subgrade is 9.9 cm wide and drops at the outside edges by 1.2 mm relative to the center. This is completely do-able so I will experiment on a foam pressing technique this evening. This calculation makes me happy and that's important to me.