Topics

Stub turnouts


Mick Moignard
 

Personally, I'd toss the Shino points, for two reasons:

1.        The frog gaps are enormous, sized for HO standard gauge wheels.  Our narrower tires drop down the frog gap and make the vehicles visibly lurch, plus the occasional derailment
2.        Shino rail metal tarnishes faster than Peco or ME, and you need to clean it sooner.

That all said, working switchstands off the tiebar isn't difficult:  I've added a piece of wire to the tiebar with a loop in the other end which lies between the headblocks.  Scratchtbuilt brass switchstands copied from Harry Brunk's MR article from about 20 years ago with the vertical rod bent in a z-shape as it leaves the lower brace. Assemble s/stand to headblock tie with superglue such that the end of the dropper is in the loop of the wire from the tiebar and the target where it needs to be for the blade position. Leave to set and operate.

Mick
______________________________________________________________________
Mick Moignard
Specialising in DCC Sound
p: +44 7774 652504
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Notes and Domino:  Rapid app development, , hi-code, low code, no code, noSQL. What else do you need?  


LARRY KLOSE
 

Re the keeper box, a similar fixture is molded into the head block of the PBL stub turnout. I used spikes as limiters on the Railway Engineering 3 way.

Larry Klose


LARRY KLOSE
 

Re switch stand connection, I haven’t got there yet. I’m holding the stands until I get most of my scenery and buildings installed. It’s too easy to “clear the deck“ while working with my big hands nearby.

Larry Klose


LARRY KLOSE
 

The Tam Valley 3 way board allows adjustment of the throw from the servo. Indeed, they do buzz when adjusted too firmly against the stops. On a three way stub, the center adjustment is done the same way but of course, there’s no stops.

I have no experience with using a servo for a two way stub or point turnout.

Larry Klose


Bruce
 

Attached is a TinderCad screenshot of the keeper box.

This is glued under the ties with the two top tabs sticking up on the outside of the rails with the split between the turnout and the moving section centered on the tab.

If I have a durability issue, I will print these with Polymax filament as it is a "tough" filament that will bend a little before breaking.  The roll I bought way back when is a medium gray.  They also have black, which might hide better.  

With cinders in your eyes,
Bruce
419-602-3584 cell


Bruce
 

John,

Thank you for your response.  I have some thinking to do!  If/when I come up with my final, and successful, effort I will post tot he group.

With cinders in your eyes,
Bruce
419-602-3584 cell


John Stutz
 

Bruce

In principal, you can take a rod off of your locking spring and use it to throw a lever at the base of your mast. rotating it from 45 degrees to 135 degrees relative to the rod.  Which is just the opposite of what a prototype rotary switch machine does.  However for a 90 degree rotation you need a lever length of about 1/sqrt(2) or 0.7 times the throw of the rails, which is a bit short and almost certainly difficult to adjust. 

Alternately build up the mast's base to make a friction drum of diameter about 1.4 times the throw of rails.  Then run a length of polyester thread (to avoid stretching) from the thrown end of your locking spring, a few time around the drum, to a very light tension spring.  You may need to adjust the drum diameter, but this diameter should rotate the mast 90 degrees, and the friction drive makes it easy to adjust the target angle. 

If the tension affects operation of your locking spring, run the thread in a rectangular loop around polished pins to the opposite side of the locking spring's thrown end, and put the tension spring in the middle of this loop.  This balances the tension spring load on the locking spring, all but the mast and pin friction.  Which also allows use of a moderately high tension spring.  A pair of pulleys could be substituted for the pins, if friction proves to be a problem, but I do not expect it to be.

John Stutz

On May 3, 2020 at 7:32 AM Bruce <in2trains@...> wrote:

....I have designed and printed a non-functional low level switch machine.  A fair looking model IMHO.  It has a hole that goes all the way from top to bottom for a wire the target will be glued to.


My "hope" is to connect the wire to the throwbar such that when your finger throws the turnout the target will rotate 90 degrees indicating the turnout's position.  I haven't nailed down the connection between the throwbar and the target wire.

QUESTION TO LARRY (or anyone): How do you make the connection to rotate the target?


With cinders in your eyes,
Bruce Bowie
419-602-3584
in2trains@...


Mike Conder
 

Interesting, Bruce, can you share a photo?

Mike Conder

On Sun, May 3, 2020 at 8:43 AM Bruce <in2trains@...> wrote:
I use a 3D designed and printed "keeper" under my turnouts to hold the over center spring mounted under the turnouts to keep the spring from over time falling out.

I have tabs on the top of the keepers used for stub switches to act as stops.  I use the Polymax filament for these as it is tougher.

Like Brian, I am hoping they will hold up over time.

With cinders in your eyes,
Bruce Bowie
419-602-3584
in2trains@...

On Sat, May 2, 2020, 8:23 PM Brian Kopp <kc5lpa1@...> wrote:
Scott thanks for the Tam Valley Depot link. 

i was curious about how you stop the switch machine (your 9g servos)at the right place. Russ is using pins soldered on the side of the outside fixed rails........ I am hoping the Shapeway plastic can stand up to a subminiature servo beating against it.

Brian

--
Brian Kopp
Jacksonville, FL


Dusty
 

With regard to 9g servos 'beating' against the stops. My limited experience with these servos indicates that they will 'buzz' if the force reaches a certain level. They have enough power to move switch points before they buzz. I think it's important to make your switches use as little force as possible. Control the frog polarity with Juicers or micro switches. There's no need for 'rod tons' of force to insure the switch points make electrical contact. DCC friendly switches are a different mind set whether they are stub or not.

Food for thought. Your opinion and/or experience may vary.

Dusty Burman 


Bruce
 

I use a 3D designed and printed "keeper" under my turnouts to hold the over center spring mounted under the turnouts to keep the spring from over time falling out.

I have tabs on the top of the keepers used for stub switches to act as stops.  I use the Polymax filament for these as it is tougher.

Like Brian, I am hoping they will hold up over time.

With cinders in your eyes,
Bruce Bowie
419-602-3584
in2trains@...


On Sat, May 2, 2020, 8:23 PM Brian Kopp <kc5lpa1@...> wrote:
Scott thanks for the Tam Valley Depot link. 

i was curious about how you stop the switch machine (your 9g servos)at the right place. Russ is using pins soldered on the side of the outside fixed rails........ I am hoping the Shapeway plastic can stand up to a subminiature servo beating against it.

Brian

--
Brian Kopp
Jacksonville, FL


Bruce
 

Larry (and Group),

I am in the process of converting to DCC friendly 30 +/- old but never used Shinohara HOn3 code 70 turnouts.  As part of the conversion I replace the metal bar that connects the points and original plastic throwbar with a plastic throwbar I designed and print using a FDM 3D printer.  I also install a bent phosphor bronze wire so the turnouts will be thrown with your finger ala Pecos.  The wires are placed under the turnout so they won't be seen once installed.  Pictures attached.  Some photos show the parts right after printing but before removing the temporary base (raft or brim) used during printing to hold the part in place on the printer's bed).

A standard PLA filament works fine in this application.  For my stub switches I have designed and printed throwbars and bridles for my code 70 stub switches.  I use Polymax filament.  It is more durable and bends a little if needed.

I have designed and printed a non-functional low level switch machine.  A fair looking model IMHO.  It has a hole that goes all the way from top to bottom for a wire the target will be glued to.

My "hope" is to connect the wire to the throwbar such that when your finger throws the turnout the target will rotate 90 degrees indicating the turnout's position.  I haven't nailed down the connection between the throwbar and the target wire.

QUESTION TO LARRY (or anyone): How do you make the connection to rotate the target?


With cinders in your eyes,
Bruce Bowie
419-602-3584
in2trains@...


LARRY KLOSE
 

My bad.  The Tam Valley board uses DC to power the servo but an accessory DCC decoder for other functions, such as signal lights in the semaphore or signals connected to the board.  It’s been long enough that I can’t remember if I used DCC for anything I’m doing with it, i.e. controlling the servo and the connected stub rails.

--------

I have 11 Sn3 code 55 stub prefab turnouts, originally developed by Tomalco and still marketed by PBL.  Installation is slightly more difficult than point turnouts because the (partially self aligning) feature of the point design isn’t present.  The stub rails are continuous with the adjoining track section and the injection molded bridles are made of Celcon, an Acetyl engineering plastic akin to Delrin.  Even though they appear very delicate, so far they have performed fine.  The turnouts are actually manufactured by Micro Engineering and Celcon is also used for the ties of the turnouts and the PBL/Tomalco code 55 flex track.  My stubs are driven by Bullfrog manual switch machines with built in micro switches to change frog polarity—the movement is transferred from underneath to the center of the bridle.  Switch stands will be linked to the outside ends of the bridle and will be working but cosmetic.  Although the prefab turnouts aren’t available in HOn3, there’s lots to learn from how they are constructed and how they install. 

 

That experience helped with the 3 way I have,  built by Steve Hatch.  It also works fine.  He puts a more robust throw bar on these, made from PC board tie material and the various multiple rails and guardrails are soldered at intervals to PC ties as well—Wood ties fill in between.  It also works just fine although it was a bit harder to lay and get operating.  Steve has a nifty control design using a Tam Valley semaphore circuit board, a servo motor and a 4 pole, 4 throw slide switch that both selects the route through the circuit board and controls polarity to the multiple frogs and routes.  It works great and in my case runs off a DC accessory bus powered by a 12v wall wart that is separate from the DCC bus.  There’s even another separate circuit on the Tam Valley board that I think I can use for the reversing portion of the wye I’m planning—I have to study the instructions again to be sure.  That DC  bus will later be used for effects and lighting in buildings and other features that will be part of my Dolores, CO. model.  My layout is currently 100% stub turnouts.

 

Larry


LARRY KLOSE
 

I have 11 Sn3 code 55 stub prefab turnouts, originally developed by Tomalco and still marketed by PBL.  Installation is slightly more difficult than point turnouts because the (partially self aligning) feature of the point design isn’t present.  The stub rails are continuous with the adjoining track section and the injection molded bridles are made of Celcon, an Acetyl engineering plastic akin to Delrin.  Even though they appear very delicate, so far they have performed fine.  The turnouts are actually manufactured by Micro Engineering and Celcon is also used for the ties of the turnouts and the PBL/Tomalco code 55 flex track.  My stubs are driven by Bullfrog manual switch machines with built in micro switches to change frog polarity—the movement is transferred from underneath to the center of the bridle.  Switch stands will be linked to the outside ends of the bridle and will be working but cosmetic.  Although the prefab turnouts aren’t available in HOn3, there’s lots to learn from how they are constructed and how they install. 

 

That experience helped with the 3 way I have,  built by Steve Hatch.  It also works fine.  He puts a more robust throw bar on these, made from PC board tie material and the various multiple rails and guardrails are soldered at intervals to PC ties as well—Wood ties fill in between.  It also works just fine although it was a bit harder to lay and get operating.  Steve has a nifty control design using a Tam Valley semaphore circuit board, a servo motor and a 4 pole, 4 throw slide switch that both selects the route through the circuit board and controls polarity to the multiple frogs and routes.  It works great and in my case runs off a DC accessory bus powered by a 12v wall wart that is separate from the DCC bus.  There’s even another separate circuit on the Tam Valley board that I think I can use for the reversing portion of the wye I’m planning—I have to study the instructions again to be sure.  That DC  bus will later be used for effects and lighting in buildings and other features that will be part of my Dolores, CO. model.  My layout is currently 100% stub turnouts.

 

Larry


Brian Kopp
 

Scott thanks for the Tam Valley Depot link. 

i was curious about how you stop the switch machine (your 9g servos)at the right place. Russ is using pins soldered on the side of the outside fixed rails........ I am hoping the Shapeway plastic can stand up to a subminiature servo beating against it.

Brian

--
Brian Kopp
Jacksonville, FL


Russ Norris
 

Scott, 

Maybe because at my age I don't see as well as I once did, but the movement of ties is barely perceptible to my eyes.  And allowing the ties to slide a little eliminates the need to find a way to keep the rails in gauge.  

Russ


On Sat, May 2, 2020, 6:13 PM ftgcss <ftgc@...> wrote:
Russ,

What I did should work with code 70 as well, you'd just need to use code 83 joiners.  I made the bridles because I didn't want the ties on the approach rails to move when the switch was bent.

Scott


--
Russ Norris, MMR
Cape Cod, Massachusetts
http://blacklogvalleyrailroad.blogspot.com/


ftgcss
 

Michel,

I'm using 9 gram servos under the bench work.  These will be controlled by Dual Three Way III from Tam Valley Depot.

Scott


ftgcss
 

Russ,

What I did should work with code 70 as well, you'd just need to use code 83 joiners.  I made the bridles because I didn't want the ties on the approach rails to move when the switch was bent.

Scott


ftgcss
 

Brian thanks,

I think you're asking me how I kept the rail joiners I soldered on to the thinned PCB tie in gauge, correct?

How I make these bridles is...

I stripped the about 3" of ties off one end of about an 8" piece of flex track.  I slid a code 70 rail joiner on each rail then laid them on the thinned PCB tie.  I then placed a "rollee holder" from Railway Engineering on the rail heads to ensure the rails and the joiners stayed in gauge while I soldered them to the thinned PCB tie.  I then slide the completed bridle off the flex track and place the bridle, joiner side down, on my desktop and trim the excess joiner with a razor saw.  I tried trimming them with a dremel and a cutoff wheel, but the heat generated by the cutoff wheel was often enough to melt the solder joint.  I then cut any excess "bridle bar" from the outside of the rail joiners and clean up and shape with a file.  Cutting the rail joiners is going to leave them clogged with a little flash and perhaps a little squished.  I clean up the flash and if necessary open up the joiner a little with the tip of an Exacto blade.  When I have enough for one switch (usually 4 or 5) I slide them on the approach rails leaving two ties between each bridle.  If the approach rails are coming off another switch you have to be able to lift the feeding switch up enough to slide the bridles on, if you bend the rails up enough to slide them on the rails and over the ties, you may bend the rails enough that there will be some vertical misalignment between the approach rail and the stub rails of the switch.(ask me how I know) The picture below illustrates this. 


Here at least one route of each switch forms the approach rails of the next so switch 1 has to have the bridles installed on the approach rails for switch 2 before switch 2 is laid down, switch 2 has to have the bridles installed on the approach rails for switch 3 before switch 3 is installed and so on.

Scott 


STAFFE Michel
 

Which motorization do you use for the 3 way stub switches?

Michel.

Le 2 mai 2020 à 19:45, ftgcss <ftgc@...> a écrit :

What I did was file down a PCB tie very thin, then solder two code 70 rail joiner on top and then trim to the width of the tie.  I used code 70 joiners on code 55 rail to ensure the bridles would slide as necessary when the switch is bent.  The extra tang on the bridle that is used to drive the "points" was left to solder a wire to drive the switch stand.  Mine aren't as detailed but they are very strong and I think they'll look pretty good when painted.

<bridles stub.jpg>

Scott


Russ Norris
 

I can see why code 55 track would be more flexible, but my track code 70 for my EBT railroad.  The south end of the yard, like the prototype, has a standard stub and a three way stub.  I left a section of the approach track free to move and found it was flexible enough for the stub.  Like others in this thread I soldered a pc tie to the rails for the bridle.  I soldered short lengths of sewing pins to the outside of the rails of the stub, with a slightly stiffer wire for the switch machine drive to make the contact secure.  I did the same thing with the three way stub, except the middle track doesn't carry any traffic.  It's purely for show.  So I did the same thing I did with the standard stub, using only the outside rails.  The stub switches operate well and I have had no problem with operating over them.

Russ Norris

On Sat, May 2, 2020 at 1:45 PM ftgcss <ftgc@...> wrote:
What I did was file down a PCB tie very thin, then solder two code 70 rail joiner on top and then trim to the width of the tie.  I used code 70 joiners on code 55 rail to ensure the bridles would slide as necessary when the switch is bent.  The extra tang on the bridle that is used to drive the "points" was left to solder a wire to drive the switch stand.  Mine aren't as detailed but they are very strong and I think they'll look pretty good when painted.



Scott


--
Russ Norris, MMR
Cape Cod, Massachusetts
http://blacklogvalleyrailroad.blogspot.com/