Allegheny Eastern: Clean Slate

[kelticsylk]

I think people may have seen the earlier plans and thought it was 15' x 15' In a spare bedroom. It takes up most of our two car garage.I thought I should show the layout in its environment...

Made some changes to Gallitzin based on ideas from the two Daves...

The helper loop is now a 13.75" radius curve. I also eliminated the "S" curve on the westbound mains. I'm hoping I left enough room to do justice to Spruce Creek. I didn't lengthen the industrial siding. Because I used broad easements on the west bound mains the tracks are too close to the backdrop.

I'll start printing this revision tomorrow and laying it out.

Regards,
Frank Musick

[kelticsylk]

I'm confused about your helix sketch.  It looks to me like you're going to enclose both the inner and outer radii as drawn.  How will you get to a train mid-helix if it stalls or derails?  Granted, if the outside is clear, you'll be able to see the problem, but...

As one who needs to build my own helix, I watch with interest.

The "sketch" if you call it that, does show both the inside and outside enclosed. The outer cover would be removable, in sections. On the drive home tonight I had another idea that is much simpler and involves plumbing parts and drywall screws...Love making things out of plumbing parts  ...

I want to stay away from the current method of threaded rod. PVC is a ton cheaper and I think I can pull it off. We'll find out tomorrow.

Frank

[MichaelWinicki]

Very good idea using the PVC!


The plan is shaping up nicely!

It will be interesting to see, since it is in an open-access environment, what the challenges will be when it comes to keep the track clean... That first year dealing with changing weather conditions and the expansion/contraction thing could prove interesting.

[DKS]

How are the drywall screws being used? Not edgewise into the ply, I hope? Suggestion: cut notches in the sides of the PVC pipe for the ply to fit into; it'll take come careful planning to get the slopes right, but it ought to go together cleanly.

[VirginaCSX]

One of the benefits of threaded rod is the infinte adjustment.  This is really benificial when trying to get a smooth grade.  How are you going to get the holes in the pvc in the right place?  Is threaded rod really that expensive?

[kelticsylk]

Questions, questions....

VirginaCSX...I am on a tight budget. Threaded rod only costs about a dollar a foot, which is about the length I need. HOWEVER, it's a lot like studding out your basement...2x4s are only about three dollars each, until you need a hundred of them. BANG! $300. I need 32 1 foot 1/4 x 20 threaded rods...Then I need about 256 1/4 x20 nuts and washers to go with them...Those are both $5.28 per 100. I need 300. So now those $1 rods are gonna cost me nearly 50 bucks. 1/2" PVC pipe costs $1.78 for 10 feet and I need about 30 feet (9" x 32 = 288" or 24 feet). I had already bought some for another project so it was already on hand.  That $50 is better spent towards the 49 feet of code 80 track I need to use on this thing, about 80 sections. Track has been the single most expensive item on the layout.

I sat a while thinking on how to join the panels together. Because of clearances I can't just stick a wood block in there and screw things together. I came up with a way in the past, but it involves more parts and overlapping joints. I ran across some wooden channel in old dollhouse kit I was throwing away. That in itself wouldn't work, but then I remembered some aluminum channel from another project that fizzeled. If I could use it on the edges of the plywood it would reinforce the helix and give the drywall screws something to bite into, Unfortunately I don't have the equipment to curve aluminum channel into spirals. So I tried something else...

I cut the aluminum into 1" pieces and then drilled holes through both sides of the channel and the plywood. Although I used drywall screws in the photo, I plan to use small nuts and bolts I have in my hardware bucket (used to need only a coffee can). I'm also going to fill the channel with adhesive caulk. These aluminum parts will be placed at every location where there is a PVC support pipe.

I know every one spends a ton of time making minute adjustments on their threaded rod, but based on the info from XTrkCAD I'm thinking that only two locations are critical, the top and the bottom. The rest of the helix is based on a constant. My helix is 9" high with 4 turns at a 1.5% grade. Each level of the helix is exactly 2.078" above the one below it no matter what level you are on.

So I take all four helix sections and join them together using the aluminum channel so that they form one continuous spiral. I then make 2" spacers (I'll fudge the .078") using pieces of the 1/2" thick extruded foam lying around the garage. The spacers will be located everywhere a support will be used. Taking yet another suggestion from Dave Smith I will notch the PVC (just a tad) and with the helix standing and spaced out correctly I will be able to see where each notch should go. I make the notches, put the supports up and screw the whole thing together. This mockup I threw together may give you visual idea of the scheme...

I used 2X4s as spacers just to see what it might look like. Didn't have much time today to spend on the layout.

The bad news is that all this has to be disassembled to lay track. Ce la vie.

Regards,
Frank Musick

[kelticsylk]

I set up the helix using spacers made from strips of 1/2" extruded foam. I used 16 spacers and placed them where the PVC pipe will go to make sure the plywwod was well supported...

I then cut a 9" length of 1/2" I.D. PVC tubing. I placed it against the spiral and marked off where the slots should located...

I made the horizontal cuts for the slots with a Japanese style pull saw ( I use them for most of my wood working projects). I used a dremel with a cutting disk to three vertical slots and then "punched" out what needed to be removed...

I took the opportunity to put some trains back on the layout, if only to see how the helix might look when completed. This also allowed me to check out the overhang on the 80 foot passenger cars.

Always need to include a track level (sort of) shot when photographing trains  ...

My Droid phone takes great photos and has become my camera of choice. Later on when the layout's more complete I'll switch to my F100 to get those realistic shots.

Regards,
Frank Musick

[kelticsylk]

Sometimes having to drop something and go do something else is an advantage. I had been messing around with the PVC pipe. I had made notches in the first "upright" by simply holding it up against the spiral and marking off the cut locations. Then I had to stop and run and errand or something.

When you get away from a project ideas seem to bubble up from deep recesses in your brain (at least they do for me). It's a lot like when you're working on a project and you quit for the night. You go home, fall asleep and the next morning the entire project is clear in your head The problem that may have stumped you the night before now has a solution.

Anyway, I'm doing something totally unrelated to the layout when this idea hits me...

Let me explain. In the photo above you'l notice that the very top of the PVC pipe supports the uppermost level. There is a notch 2" below the top, and another 2" below that one. A third one lies 2" below the second one. Finally at the bottom the pipe sits on the plywood that supports the entire helix.

This is true everywhere on the helix. The top of the pipe supports the uppermost level. Below that there are always 3 notches all spaced at 2" intervals. The only dimension that changes is the length of the pipe between the lowest notch and the table top. This means I can gang cut, or mass produce the 32 uprights. They can all be the same length. To make the upright work in a certain part of the helix all I need do is trim the bottom of the pipe...

Once the helix is assembled the bottoms of the uprights could be trimmed to suit.

One more thing occurred to me while I was making the drawing above. If I place a plywood table top under the helix I can simply bore holes to accept the uprights. This would eliminate the trimming altogether. I'll have to look into this and see how it would be fastened to the layout.

Regards,
Frank Musick

[kelticsylk]

In our last episode our intrepid model rail was trying to come up with a way to hold up the helix.

In the last set of photos I showed a notched piece of PVC pipe that would serve as an upright to support all 4 layers of the spiral. Using this idea I also came up with another way to join the helix section together. Each level has it's own 360 degree plywood panel. This means all the seams are stacked above each other. There are only 3 places where a lower level connects to the next higher level. I was going to use aluminum channel to join the sections, but then I started playing arond with the PVC uprights. It occurred to me that I didn't need to join the panels together directly. I could use the uprights to support each level and connect one to another. I came up with something like this...

The idea here is to glue uprights to the plywood on each side of the seam. Then the seam can be closed by drawing the two sets of uprights together and then fastening them permanently. Not sure what I'll use for that yet. My first thought was large hose clamps, but there might be a more "elegant" way.

The uprights take time to make with all the cutting and notching and it's hard to get nice clean notches with hand tools. If I still had my table saw I could set up some widget that would notch the pipe every two inches in a nice straight cut. Then somewhere out of the blue I realized all the notches were unneccesary.

If I cut the pipe into 2" lengths I get what are essentially spacers. These spacers fit between the levels in such a way that they can be glued to the plywood directly. Each level now has it's own support and will sit 2" above any surface it's placed on. This includes another level of the helix. All spacers are located so that they all have the same center as the level below. Essentially, it's like those stackable bridge supports that come with Thomas and some other toys.

The only place where the 2" spacers wouldn't work is the bottom level. There the spacers may have to be cut to various lengths to maintain the 1.5% grade. If , however, holes are bored into the table top supporting the helix on the same centers as the spacers the supports don't have to be trimmed. They can be set to the proper height and glued in place.

So what keeps the spacers in their relative positons? There are a couple of ways to make the spacers interlock. One is to take a smaller diameter PVC pipe that fits inside the spacer. They would be the same length but offset vertically about 1/2" so that each spacer would interlock with the one above it. It would something like this...

The second way is to just drop a pipe through all the spacer and pin them together like this...

Some of the spacers are a bit sloppy because they are recycled from the notched uprights used on the previous "experiment". I making much cleaner ones using a thingie I'll show you in a bit.

This is much simpler and easier than the interlocking spacer and is the route I'll take. I used a steel pipe I had laying around but I'm planning to buy smaller O.D. PVC pipe. Using PVC for both parts means I can permanently join things with PVC cement. There is little chance that will ever come apart.

Rather than repeat all the work to measure all these parts and mark them off for cutting, etc. I created this little gem...

I dug out my old Buck miter box that no longer cuts square. I made new slots in the oak sides to fit my pull saws. I the fabricated a stop out of 2x4's and set it at 2" from the saw slot. I'll use this to cut all the spacers to the same length. I'll then move the stop (just undo the screws holding it to the miter box) and set it for 9". Then I'll cut the pipe sections that will serve as a pins. Since I'm boring holes into the table top, I'll probably get PVC end caps and clue these to the pins to keep them from falling through.

Regards,
Frank Musick

[GaryHinshaw]

This looks very inventive Frank, but I'm having trouble understanding why you prefer a tube shape for these supports vs. something flatter, and potentially easier to work with, like wood.  I would be tempted to cut a set of posts from 1x2 stock the full height of the helix, and a series of identical support blocks in a slight parallelogram shape. The blocks could be screwed and/or glued to the posts in a pre-set pattern, something like this (shown with a greatly exaggerated gradient for illustration):



This gives you more support area at each piece, and you could bang the blocks out with a chop saw lickety split. You could then tie the posts together at the top and bottom with wood cross members, like Mark has done on his Columbia & Western helix:

https://www.therailwire.net/forum/index.php?topic=27514.msg283191#msg283191

Just a thought.

-Gary

[kelticsylk]

Gary,
A- Don't have a chop saw. Gave my radial saw to my son-in-law. I use razor pull saws for all my real cabinet work. The lone circular I still have is fused mainly for gang cutting 2x4s and some panel cuts. If I need plywood cut into larger shapes I let Lowes do it for free (I kick myself every time I go to Home Depot, they NEVER  have what I need )
B- PVC is cheaper. less than $2 for 10 feet.
C- The helix is is for N-scale trains. How much support is required?
D- Cause I'm eccentric and like building things inexpensively from odd materials 

Since the helix has 32 uprights any support along the roadbed should not be a problem. Across the roadbed the width is about 6" Even thin  plywood is very sturdy within such a distance.

You did give me a seque (always wanted to use that in a sentence  ) to the point of this entry. I has occurred to me that I should have cut the helix panels with "ears" at the location of every support...

Because I didn't I may have to retrofit some ears...

If I can find a shape like this at Lowes in PVC I'm set.

Duty calls. Off with my wife to do some shopping.

Regards,
Frank Musick

[GaryHinshaw]

My bad, I thought I'd remembered that you did have a chopper.   I'm curious to see how the ears work out, and I'm impressed how quickly you can pop these drawings out.   

[kelticsylk]

Thanks Gary.  I was a draftsman (or draughtsman as they say in the King's English)in my first career. Had a lot of practice on the drawing board and CAD systems.

I've mentioned before that design can be an evolutionary thing (more often than not) and that the best solutions come when you walk away from the project. I was out shopping and looking for something to retrofit the "ears". Something like a screw eye maybe or some weird plastic picture hanger with the correct shape. No luck. Walking down the aisles at Michael's I suddenly realized that the "ears" were unnecessary. The helix panels are about 7" wide. The tracks are on 1 1/4" centers (because of the wider radius curves this is actually plenty of room for 80 foot cars to pass each other). The track is only so wide, there is no ballast strip in the helix to worry about, etc, etc and so on. The short story is that the helix panels are wide enough to fit the track and the spacers. All I had to do was move the spacers in...

This also solves the issue of the gap between the spacers (opposite the plywood) and creates a bigger contact patch for supporting the panels. It also means the pin that aligns the spacers also holds the helix and all its panels in place...

There was also a bit of serendipity. I had lined up the first helix panel exactly where I wanted before drilling the holes for the pins...

When I drilled the hole, the bit also went through the table top under the helix. I realized I had just found a way to anchor the spiral in place. Since only the pins can fit through the whole bored in the table top, I may need to trim some of the spacers that support the first level. I could also just block it up with pieces of scrap 2x4 but I think I'll go with the spacers.

Just to be sure of the clearances, I laid some track for the eastbound freight main. This the only track that would cause an issue if a train collided with an upright. I dug out the Allegheny Easterns 80 foot executive car "Blue Heron" and rolled it past the spacer...

If the passenger cars have that much room there is plenty of clearance for the freight trains that normally use that track.

Now that the experimentation is over it's time to start the actual construction. More on that later, that 5 hour shopping trip wore me out 

Regards,
Frank Musick

[Zox]

That's some very nice R&D work there, Frank. I always enjoy seeing new solutions to common problems, and this one's excellent. I suspect, when all's said and done, that your approach may become a new standard--economical, simple to assemble, made of readily sourced and/or fabricated parts.

I look forward to seeing the construction progress, as well as the final result.

[kelticsylk]

Zox,
I started assembling the helix today to see how it all fits together. Took quite a few photos of the prep and assembly process. I stacked all four levels so they were all alligned. I placed the one I had already laid out on the top and screwed all to the table top with drywall screws to keep them lined up.

I then drilled pilot holes wherever an upright would be located....

When I got all the pilot holes drilled I went around again with a bigger bit (5/16")  Then I finished up the holes with a 1/2" bit Drilling in stages like this prevents tearing up the plywood and keeps the holes better aligned.

Now I started working on cutting all the spacers and pins. I went back to Thing 2 (the jig that cuts the spacers) and made some "performance" enhancements. The addition of a "guide" and another clamp made sure the pipe was held in more securely when sawing the 2" spacers. I then cut the pipe with a razor pull saw (sometimes called a "japanese" saw). The blades of the saws are VERY sharp, very thin (almost as thin as a Xacto razor saw) and can be very accurate is you take your time. I started using them in all woodworking projects. They can cut fast and straight. I've been able to make almost paper thin slices with these things...

I cut the dowels with the simplest jig you can make, what I call Thing 3. I simply measure and cut the first dowel and then use that dowel as guide for cutting all the others...

With all the parts cut and drilled I started to assemble the spiral. I started by sliding the first level down over the pins. I then fastened the beginning of the helix to the table top with drywall screws...

I didn't use any spacers on this level. Instead I made piers of styrofoam of various heights to maintain the grade. 360 degrees from the start I put in the first set of spacers The end of the first level was now 2" directly over the starting point...

I placed spacers on the pins all around the helix and slid the second level on to the pins. It takes a bit of pushing and persuading to get all the pins in all the holes but the second level was now in place.
 

The assembly fits together well enough that I believe there is no need to use the aluminum channels for holding the ends together. The location of each panel and pin keeps the ends together without any extra fastening or reinforcement.

I'll continue on with assembly later on.

Regards,
Frank Musick