Well done, Devon. I don’t see any reason that won’t work. Will you have a way to tell which way the switch is thrown from the floor?
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I actually have spent a bit of time thinking about this. The nice thing about where this switch is going is it can have a full 3 feet of rail leading into it. So the unfixed moving sections of rails can be fairly long. So they should bend easy enough.
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Yes I will put a harp style stand on the throw with a nice big flag. I like the harp style anyway and for a stub its nice because it clearly indicates which way the switch is thrown since it does not rotate but moves in the same line as the point rails (though if I am not mistaken its opposite).
Good News, the entire switch as shown will fit in my printer. It will be a long print as its taking up most of the height to get it to fit but it is not vertical and has still enough angle that it should print just fine. And since it is not a detail part I can live with things like build lines should they occur. I think this will work out just fine.
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Looking forward to seeing what comes out of the printer.
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That depends on what kind of wheels you are using. Finescale wheels require the frog guard rails and check rails to be further apart. LGB wheels need a wide gap. There’s no simple answer.
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Well honestly i don’t know what wheel I will be using. I am going to assume I will need some forgiveness in this area. The motor block I am using for both locos that will run on it are bachmann lil big haulers. I would say that would be the widest flange.
If my printed wheels for my cars don’t hold up then I will likely use the small bachmann wheels.
I have it set at 3.5mm does anyone see this as problematic?
If it were me, I’d try printing shorter sections flat against the build plate. Really quick printing that way, zero supports, no distortion, and super flat underside. It would take a few test runs tho to get the rail flange width corrected for the natural spread of the resin against the build plate. And I’d print with supports between rails, perhaps the topsides of ties even, to maintain everything while knifing off the build plate.
Just my 2 cents.
It won’t fit on the plate flat unless I cut it down. I might have to play with it and see how much I can shorten it.
I could slice it in half I suppose
That’s what I’d do.
But do it your way first and be your own judge.
Actually Cliff I am thinking I like your way. Would be easy to do. And would be a much faster cleaner print.
Even flat on the plate the curl won’t bother me. First you won’t see it on my ceiling and Ballast would cover it anyway. I think that’s the route to go
It probably doesn’t matter for this project, but a frog should not have any curved lines in it. The running rail should straighten just before entering the frog.
This old diagram I found on the web years ago might help at least with naming conventions…
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Jon,
I couldn’t agree more. And in no way would I think to do this in a “normal” situation. But this is a special case that breaks all the rules. Its a compromise between what’s proper and what needs to happen.
I used to not really understand why. But after enough reading about it awhile back I understand why it’s problematic
At least it’s a quick test. Maybe on a piece of track an inch or two long. With a bit of frog maybe.
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Hmmm Is it done yet ? 
As Jon posted the diagram, (I was just about to) I’ll refer to it.
Devon - I’m not even sure where your 3.5mm gap is located. There are 2 critical gaps. Between the wing rails and the frog, and between the stock rails and the check rails.
When a wheel set runs through from L to R, the back of the wheels is controlled by the check rail to prevent the wheel from heading the wrong way down the frog. If your back-to-back wheel measurement is finescale (1.575" or more) then your gaps need to be tight. If you are running wheels with thick flanges at less than 1.575" then the gaps should be wider.
In 60 years of making switches and frogs, I concluded the only “universal” way to do it that controls all kinds of wheels is to make the gap at the frog/wing rail wide and the gap at the stock/check rail much smaller. You want to hold all kinds of wheels against the stock rail.
The problem is that most wheels will drop into the gap at the crossing/point of the the frog before riding on the frog. Hence you need to build up support for the flange so it rides on the support and doesn’t drop too low. [What is supposed to happen is that the wheel smoothly transitions from the frog point to the wing rail or vice versa without ever being unsupported.]
There was a discussion recently about LGB frogs. I’ll see if I can find it.
Edit: here you go - 2 good threads to review:
https://www.mylargescale.com/threads/issues-with-other-manufacturers-on-lgb-turnouts.91945/
https://www.mylargescale.com/threads/switch-frog-groove-depth.27202/
Thanks Peter. I am pretty sure I followed you. Unfortunately since i really have not yet decided on a wheel set I can’t answer that question other than to say I doubt seriously that I will be using fine scale wheels.
The loco motor blocks are Bachmann Lil Big Haulers and are certainly NOT fine scale. For the cars I will run on this I have three choices I am playing with. The first will be my own printed wheel IF i can find a resin that I think will be tough enough to do the job and hold up over time, I am highly doubting this. The second and most probable choice will be to use a spoked wheels from the “train department” that are made for small 7/8ths cars. Not sure how fine of a profile they have but in the pictures I don’t think I would call them fine scale. The third choice is would be the Bachmann small whee lsets.
Now I am not really sure how to label my rails in conjuction with the diagram but I am sure I can muddle my way through so you get the picture. Since I am building a stub switch I will start from the left in the diagram. So I don’t have “points” I have two independent sets of rails the ones that will go straight through and the diverging rails. The are set so that the facing edges are set 3.5mm apart. I wouldn’t think this would be an issue of being too wide as much as not wide enough. Since the rails leading in from the left that slide back and forth are whats determining things. provided I make the stops perfect so they line up with two sets of rails.
Moving to the right I have a 3.5 mm gap between the same faces (the ones that oppose each other forming the gap) of the check rails and the running rails. And by the same token I have a 3.5mm gap between the wing rails and the running rails.
Now the ne place where I do understand what you are saying and the only time I have ever treid to make my own frog before is the crossing. I do see what you are talking about with the wheel dropping in. I did struggle with that before. given that everything has a 3.5mm gap will I have an issue with wheels dropping in? I also realize this has to do a lot with wheel diameter and I am using smaller diameter wheels so I suspect that will make the problem worse.
So I do think I followed you Pete. And if I were actually hand laying the switch with components in hand it would be a lot easier to see where adjustments need to be made. Doing it in a virtual world is a little different, I can’t move things around and run a wheel over it.
So with this discussion and what I have said about where and what gaps I have, is there an obvious inherent problem that I need to address before I print my first teat track and see what happens? Not having built them before I don’t have a trained eye to see what you more experienced switch builders will see as glaring.
Nice thing about printing is that its only resin. So if I print one and it doesn’t work its not the end of the world. But I would also like to fix any galring issues that someone might see right off.
Unfortunately you can’t really tell until you try it, and I can’t advise until you decide on the wheels. If you are using a L’il Hauler then the back-to-back will be about 37mm or less. As your track is 45mm face-to-face, and you are using a 3.5mm gap, then your check/wing rails are 45mm-3.5mm-3.5mm = 38mm apart. The 37mm back-to-back wheels will bump over them or stick/jam in the gap.
Measure your wheel back-to-back and make the wing-frog gap wider if necessary.
Not necessarily. They may drop in but they may not derail, just bump over the top. My pal has finescale track and some of my locos just bounce over the frog/wing rails as they are too tight, but they don’t come off the track (usually.)
You do need to design a flat inside the gap for the wheels to run on. The L’il Hauler will have much deeper flanges than your own wheels, so you should measure the depth of the flange and decide whether the loco is going to lift up on the support inside the gap while your wheels trundle merrily through, or whether the loco stays on the same level but the wheels dip in with a noticeable bump.
Again - it may work anyway.
Followed all of that Pete. It had never occurred to me adjust the gap for the back to back but makes perfect sense. Also th eidea of having a support at the crossing gap to support the wheel across the gap. This is why I love this site. All the little things I would have had to work to are already solved. I will revisit his in my CAD drawing before printing.
Thanks Pete
I just measured the back to back on the lil Big Hauler wheels. Its right at 40mm . Flanges are about 1.5 MM thick at the base and about 3mm tall. Now that I am thinkin in the right regard as to designing the switch/frog for the wheels I am using makes much more sense to me in figuring it out. Its a more solid approach. So I will sit back down with the drawing and rework it if need be to match the wheels.
I would think the chunky Lil Hauler wheels will be the limiting factor, any thing I design will be finer.