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Multiple Staging Tracks & access to them

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  • Member since
    December, 2001
  • From: Northern CA Bay Area
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Posted by cuyama on Tuesday, April 03, 2018 11:37 PM

Doughless
What's the normal way?  Build a center support then provide access around the outside of whole thing?  Accessing 2 feet around a 4 foot helix would require 8 feet of space.  That's a big footprint of floor space.

I've designed dozens of layouts with helixes -- most of which have been built. They are usually against a wall, often in a corner, and access from below through the center for at least a portion of the helix is typical. 

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Posted by railandsail on Thursday, April 05, 2018 11:15 PM

Continous Staging Tracks rather than just Dead Ends

previously by Brian
By varying the short straight track sections prior to those multiple curves we can get greater spacing between their centerlines, and greater spacing down the 'fairway' (the straight track sections down the (each) side of the shed....)

My original idea was to have those 2 staging areas on either side of the room, consisting of 5 tracks each, simply extend to the end of the room and dead end there. Staged trains would be backed into each of those 10 tracks (5 tracks x 2 sides), ready to pull out forward and enter the staging access helix to go to the main layout deck. That dead end of those tracks would be at the end of the shed opposite the helix end of the shed,...that is the door end of the shed.

The gentleman who is welding up my brackets ask me, "why not make another removable bridge across the door entrance to join those two sides of the dead ended staging tracks, then the trains could pull forward continuously thru the staging tracks?"

That's not a half bad idea. If I provided such a removable bridge between the dead ends of those 5 tracks down each side, it could offer the alternative to utilize the staging in such a fashion if so chosen in the future. I think I will provide that option.

Drawing to come.

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Posted by railandsail on Wednesday, April 11, 2018 7:07 AM

As I said, drawing to come. Here is my current sketch.

 

Lets start with getting to the staging area(s). There is a track right next to the wall on the left hand side of the shed at the rear corner that enters the OUTSIDE curve of the track helix. It begins its descent inside the shed just after it crosses over that last major bracket supporting the main level deck. By the time it reaches the 9 o’clock position on the helix it is at a -1.5”. It subsequently drops 1” for each quarter turn around the helix, ending up at -7.5” at the 3 o'clock position, and subsequently -8” at the 3-way turnout at the entrance to the 3 area staging. That is a little less than a 2% grade (1.8% I believe).

Now it can branch out into 3 directions, ...5 tracks on either side, and an undetermined number down under the straight peninsula. At the head of each side track(s) there are 4 Peco medium radius turnouts that feed 5 tracks that ALL make the same 24” inch radius turn into the straight sections of the staging.


 

 

Those 10 straight sections (5 each side) of staging make turns at their 'tails', and can either dead end at the bracket that is located to either side of the big door, OR there will be a lift-out bridge provide that could connect the 5 tracks continuously. The radius’s on those staging track tails are progressively built in 24”, 26.5”, 29”, 31.5”, and 34” so as to maintain a 2,5” centerline between themselves. Other than in the 4 corners of the layout, the shelf depth required for these generously spaced staging tracks is only 14” from the wall.

 

The staging level deck will be constructed of the same 3/4” plywood I purchased for the main level deck, and will be supported every 24” by a combination of metal brackets fashioned from the same 2” square, and 1.5” angle iron I am planing on using for the main deck above it. That is probably 'overkill', and the staging areas may just utilize the angle iron material.

 

 

Not yet shown in this dwg is a central spine support down the peninsula built of the 2” square tubing to be very minimalistic yet strong.

The helix itself will be 'housed' in a trapezoidal shaped box formed on four sides using some 1.5” square alum sections I salvaged from some screened in porch/pool structure here in Florida. They will intersect with some 64” steel circles I am having bent up from 1.5” angle iron. Those two steel circles (one top, one bottom) will be joined by 12 vertical post made up from 1” square alum sections I salvaged elsewhere. It should be strong, and rigid.

 

 

Alum siding will be attached to the outer perimeters of the framing and the top cover. There will be some sort of trap door in the bottom to keep pest out.

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Posted by railandsail on Sunday, April 29, 2018 12:46 PM

3 Zones of Staging

 

I haven't revisited this subject thread in quite awhile,...because I have been working on the plans, and the helix modification, and start of the helix construction.

For the moment I'll just post this drawing of the 3 zones of staging. There will be 5 tracks to either side of the room/shed. These will be mounted on a 12"-14" board of 3/4 plywood cantilevered off of a very substantial metal framework attached to the 2x4 studs of the shed.

Then there will be 5-6 tracks down the center under the peninsula.  These will be off to one side of, and cantilevered to 'metal frame spine' that will support both the peninsula main deck and this staging deck.

...more to come

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Posted by railandsail on Wednesday, May 02, 2018 8:54 AM

Lower Segments of Helix Structure

The track going down its portion of the helix structure to staging will start its downward path slightly before it exits the left hand rear of the shed, then proceed to utilize the outer loop of trackage to eventually dive under the level balloon loop occupying the inner trackage.

 

 

The simple level 'balloon loop' just above that helix segment going down to staging. It occupies the inner trackage of the double track helix structure.....

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Posted by railandsail on Thursday, May 03, 2018 10:10 AM
Helix Spiral

For those having a little problem visualizing my multideck spiral within the helix structure, here is another view....
(that B is for 'balloon loop')
helix spiral.jpg
 
The top & bottom 'balloon loops' are single track ones, The helix down to staging tracks is also single track.

The helix between the top and bottom deck is double tracked
  • Member since
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  • From: Dallas, TX
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Posted by CMStPnP on Sunday, May 06, 2018 6:58 PM

Make sure you test once you have the track laid or temporarily lay the track without roadbed with  just rail joiners (which is what I did) so you can test before you permanently lay it down.    I have a double track helix, 22 inch outside, 18 inch inside.   I am going to put a X crossover at the bottom and top so the passenger trains can always use the 22 inch track.     I will second the comment on checking clearances on cars you own.    Was surprised to find the Walthers Hiawatha Cars cannot make a 22 inch radius turn without some modification (remove some diaphrams), other manufacturers, OK.    Also found on at least one Walthers car but not another, trucks needed spacer washers as top of the trucks were binding with underframe on sharp curves.    Seems like Walthers has quality issues with uniformity or else I have a bad car.

Also, with your Helix diagram above, beware that at times you might be inadvertently reversing rail polarity depending on what your feeding into it above.  Not a road block issue as you can install reversing units or electrical switches to flip or cross a polarity conflict with two loops and two helixes you might have that issue times four.

I did not do my own helix, had someone else do it for me to ensure the clearances top to bottom with roadbed and side to side with curvature were all OK.    I was told it can handle double stacks with roadbed but I need to test that still.    I have a hole in the middle of my helix but since I can access it on three sides and have long arms ...........probably will not use the hole.

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Posted by railandsail on Sunday, May 06, 2018 10:38 PM

I did quiet a bit of experimenting with clearances required for long locos and freight cars, passenger cars, and double stacks. You might have a look thru some of these results and photos;
http://cs.trains.com/mrr/f/88/t/267707.aspx

In general I found you don't want to go with less than 24" if you are running those long cars, and steam locos

I'm not using any roadbed (cork, etc) under my track in the helix,...don't find it neccessary. I am shooting for 4" height clearance, even though 3.5" will work in most instances.

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Posted by CMStPnP on Monday, May 07, 2018 11:26 AM

railandsail
In general I found you don't want to go with less than 24" if you are running those long cars, and steam locos

Not a steam fan so no steam locos for me.    Already tested on the 22 inch all work OK on it but can use flex track to increase to 22.5 or 23 inch radius.    18 inch I need to test and I am worried about it.    I might just break down and use flex track for the inner loop as I think 18 inch is ridicullously tight and allows way too much clearence.    So it might end up as 19-20 inch.

I outsourced my benchwork so I had some say but also had to be realistic to what would fit in my small bedroom, if they went beyond 22 inch radius in the Helix I would not be able to loop in 22 inch on the other end opposing the helix and still leave enough aisleway clearance.    So compromises were made.

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Posted by carl425 on Monday, May 07, 2018 3:29 PM

Next to the double slip, the 3-way switch is the most high maintenance available.  How do you intend to provide access to the 3-way that leads to staging?

I have the right to remain silent.  By posting here I have given up that right and accept that anything I say can and will be used as evidence to critique me.

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Posted by railandsail on Monday, May 07, 2018 9:54 PM

@Carl,
I am paying particular attention to that access problem. I want to be able to get at any derailments that might occur there, and I want to be able to replace that turnout if that becomes necessary.

I'll be installing it with these thoughts in mind. I plan on having an external (to the helix structure) access door that will allow more direct access. It will also not have any trackage over the top of itself. And it will also be on the very bottom level of the helix structure.

I've almost firmly decided to utilize a really nice Peco 3-way that I feel most comfortable with.

 

 

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