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Manual Point Control


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Hi Alan

Good luck with your shopping.........I`m sure you will develop a system that works well for you. I have just been looking at some model aircraft bits and I have found some of those dreaded bellcranks. They are reasonably priced ..........please see the link

 

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXD938&P=7 They might be usefull

 

Cheers Gormo

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Keith

 

I've been meaning to ask... what exactly does the 'underside' of your curtain track look like? I've never bought any, but does it have channels for the rod to slide along... and how do you attach the wire that links to the tie bar? Just trying to gather my thoughts together before taking the plunge!

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what exactly does the 'underside' of your curtain track look like?

Look in here and scroll down to the TOU Turnout Operating Unit section. Tells you more about it but does not really show you how it looks, I'll try and take a photo tomorrow.

The subterrainian tie bar is a piece of perspex and the vertical rods are hypodermic needle tube, a piece of nickel silver wire soldered to the point blades fits into the tube and hence is free to rotate.

Note, these units have not been sold for over 20 years now, I don't know if you can buy the same track but people make their own up from various sizes of square plastruct tube or you can use the Exactoscale tortoise adapter plate which works in the same manner and can be used without the tortoise. That would be my choice if buying now.

(On the Exactoscale/P4 Track co site click on the "instructions" button in the header menu, then choose products for any scale).

Regards

Keith

 

 

 

http://www.scalefour.org/history/p4tracklaying.html

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That's really helpful Keith. Thanks very much for posting the photos. Wonder what google will come up with when I ask for a source for hypodermic needle tubes!

 

Do you think I'd be right in thinking that, as I'll be using the tie bar in peco points, a single link to it would be fine?

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Wonder what google will come up with when I ask for a source for hypodermic needle tubes!

While it is possible to buy the hypo tubes its much easier now to buy brass tube from Eileens or Finney and Smith, 1mm inner dia, 1.5mm outer diameter is fine, there is no need to be as small as the hypo tubes.

 

Do you think I'd be right in thinking that, as I'll be using the tie bar in peco points, a single link to it would be fine?

Certainly, for Peco points you can forget the tubes and just use a vertical piece of 1mm piano wire. (The tubes are there to provide a pivot so that there is no torsional stress where the wire is soldered to the point blades, in a peco point just use the hole in the centre of the tie bar that acts as its own pivot.)

Keith

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Hope the OP doesn't mind me tacking on some photos onto this post.

 

I've been using using "snakes" as part of my point control system. That's partly because I hate wiring up point motors, but also the layout is going to be used by my children and I prefer to keep things simple and easily mended.

 

On my layout there are times when the snake has to pop up through a hole in the baseboard and be attached to the side of the tie bar, rather than through the hole in the centre of the tie bar. As the points will be not be easily accessible I wanted to find a robust way of connecting the nylon rod inside the snake to the tie bar. To do this I cut out the brass connector from a choc block, with the nylon rod on one side and the tie bar to the other side. To do this I needed to cut off the nobbly bit on the tie bar.

 

post-4299-0-23006600-1336823968_thumb.jpg

 

Where it was possible to drill up beneath the point's tie bar I wanted to find a simple way to both guide the movement of the snake and translate this movement up into the tie bar.

 

Again I wanted something robust and simple.

 

I came up with the idea of using 3 choc blocks, 2 of which are attached to the baseboard and the 3rd travels freely between the outer pair with copper rod used to keep it on the straight and narrow. The photos below show the general arrangement and hopefully should give you the idea of how I went about it, should you want to give it a go.

 

post-4299-0-18159500-1336824912_thumb.jpg

 

post-4299-0-04738100-1336825126_thumb.jpg

 

One refinement which allows the centre choc block to slide more easily bearing in mind the whole mechanism is screwed tight against the baseboard) is to offset the mechanism from the baseboard using two pieces of scrap cardboard.

 

The pin that fits into the tie bar is fixed in place using epoxy resin, as the outer sheath (yellow) of the snake is fixed to the choc block.

 

post-4299-0-89331700-1336825533_thumb.jpg

 

 

Hope this simple idea is of use to you guys and gals.

 

All the best, Andy

 

 

.

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Hi Andy

Another brilliant idea...!!!!........excuse my ignorance........but " snakes "..........is this another model aircraft part adaption...????.......I am not familiar with this product..........and I feel it may be very useful....

 

Cheers Gormo

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@ Gormo, "Snakes" seems to be the name for control cables with the model aircraft fraternity. I saw them reviewed in the model railway press a year or so back and gave them a go.

Here's the link: http://balsamart.co.uk/store/index.php?main_page=product_info&cPath=207&products_id=1248&zenid=15fd3806d96f8ce734992a2605f1bba7

 

@BReaslitic, at the operator end I drill a hole through the baseboard framework just slightly larger than the snake. I fill the hole with either decorators caulk or bathroom sealant and then push the snake through.

 

I'm thinking of finishing the snake off with a small wooden toggle (or ubiquitous choc block! mainly to prevent small people poking their eyes!

 

Glad you both liked the idea.

Andy

To tidy up the snake to the baseboard you can either use metal staples, tape, sticky feet....

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@ Gormo, "Snakes" seems to be the name for control cables with the model aircraft fraternity. I saw them reviewed in the model railway press a year or so back and gave them a go.

Here's the link: http://balsamart.co....4992a2605f1bba7

 

@BReaslitic, at the operator end I drill a hole through the baseboard framework just slightly larger than the snake. I fill the hole with either decorators caulk or bathroom sealant and then push the snake through.

 

I'm thinking of finishing the snake off with a small wooden toggle (or ubiquitous choc block! mainly to prevent small people poking their eyes!

 

Glad you both liked the idea.

Andy

To tidy up the snake to the baseboard you can either use metal staples, tape, sticky feet....

 

Hi Andy

I realize now that a similar product was referred to earlier in this topic............Cheers Gormo

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Howdy from across the pond. I use "bat handle" switches from Radio Shack and 1/4" dowels as push rods, secured on an L bracket.

 

I start with the bracket. Its called "truss tie", its made from stamped sheet metal, has a long grove stamped in the long side and two screw holes in the short side. I use a Unibit to drill a 1/2" diameter hole in the bottom of the slot. Then in the short leg (top) I drill a 1/16" hole even with the end of the switch handle.

 

IMG_3812.jpg

 

For the simple mechanism, hold the switch so the handle is horiszontal and the switch throws left-right. Drill a .040 hole vertically in the plastic switch handle near the end. Drill a 1/16' hole horizontally through the handle of the switch.

I then cut a 3 terminal piece of a "European" terminal strip. The Radio Shack switch is attached through the 1/2" hole. The terminal strip is bolted to the bracket with a 4-40 bolt through the slot. Run feeder wires fro the switch contacts to the terminal strip.

 

IMG_3819.jpg

 

For the simple mechanism cut a piece of .039 piano wire, drop it through the 1/16" hole in the top and glue (ACC) it into the .040 hole in the handle.

 

Drill a 3/8" - 1/2" hole under the throwbar of the switch. From the bottom stick the .039 piano wire up through the hole into the throwbar of the switch. Use two 3/4" drywall screws to secure the bracket to the underside of the layout. Drill a 1/16' hole vertically through the end of a 1/4" dowel. Stick a piece of 1/32" brass rod through the hole and wrap the bottom end around the dowel. About 1/4" above the dowel, make a 90 degree bend in the rod with the free end pointing away from the dowel. Feed the free end of the dowel through the fascia, and stick the brass rod through the 1/16" hole in the handle of the switch. Bend the brass rod down to secure it to the switch handle. Trim off the dowel sticking out of the fascia and glue a wood ball or spool as a handle if desired. Wire the feeders from the frog and bus wires to the terminal strip.

 

I also use PVC pipe caps as fulcrums to "turn" the action of the pushrods.

 

IMG_3811.jpg

IMG_3815.jpg

 

I personally use a more involved mechanism that has more more moving parts. I glue a piece of Plastruct angle to the end of the switch handle then drill and tap a 2-56 screw in to the end of the switch handle. I solder the .039 wire to a 1/2" square piece of brass shim stock, drill a hole in the center of the shim and screw the shim to the end of the switch handle. That allows everything to rotate, leaving very few bending forces on the mechanism.

 

IMG_3811.jpg

 

I also like recessed controls because I have a narrow room. So I have raised the layout subroadbed about 6" above the 1x4 framework and then recessed boxes into teh fascia with the push rod ends in them.

 

IMG_3775.jpg

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Howdy Dave

Thanks for the contribution to this topic. I like the use of the switch to shift the tie bar. It`s a combination of processes and quite economical I would imagine. I like the simplicity of the system........sometimes we tend to over engineer things when it is not necessary. The use of the switch intrigues me and I am wondering whether I might adapt it to my system. I also like the recess idea.....it makes a lot of sense to keep controls behind the edge of the baseboard.

 

Cheers Gormo

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If I was Harry Hill I'd be shouting F I G H T... between Gormo's hinge and Andy's choc block!!

 

One question Andy, how exactly do you fix the outer sheath (yellow) of the snake to the choc block... without pinching the inner plastic rod?

 

Like Gormo, I'm getting rid of the spring mechanism that holds the point blades against the stock rails. This means (I think!) that, at the operator's end I need something like Gormo's Nyloc nuts to hold the lever in place once it's thrown. Unlike Gormo, though, I don't have the wherewithal to make my own levers. (yours are a thing of beauty, Gormo!) So, I'm wondering if there might be anything 'off-the-shelf' I could use instead. Something 'chunky' (like Gormo's!) that can be held in a bracket by a Nyloc nut AND have a means for attaching the inner rod of a plastic snake? Not asking for much, really!!!!!

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@BReaslistic. Good question, the yellow sheath is actually simply butted up to the metal inner - it's slightly larger than the metal inner piece. Fixing it, therefore, was a real pain in the proverbial. I tried a drop or two of Superglue - a non starter. Then I tried epoxy. This worked ok, before it was fixed to the baseboard. However, this failed soon thereafter as the movement of the nylon inner caused the outer sheath to flex, quickly weakening and then breaking the epxoy joint. I should mention it is important to either tape or somehow fix the snake to the baseboard at a number of points to avoid flexing.

 

So, the solution that worked was (drum roll) decorators caulk smeared over the choc block / snake join.

 

The only think I'd like to do is find a source of wire / rod that I used to poke through the point's tie bar. I used a long pin snipped from an old Peco point motor.

 

Anyone got a better and more economical source of these kind of pins ?

 

Anyway give it a whirl and see if you can improve it.

 

Andy

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Cheers Andy. Nice that I have some decorator's caulk already... unless it's gone off! Thanks for the tip about fixing the snake to the baseboard. I think I saw some fastener things on that web site you gave a link to.

 

Re the wire to the tie bar, I've often come across piano wire being recommended... although it's crossed my mind that doesn't it come in various thicknesses?? Gormo uses wire that's 0.90mm thick (see his Parts pdf) and I guess he'll be along in a min to give us his (valued) thoughts! I see Dave uses .039 inch wire, which, I bet your bottom dollar, is 0.90mm or therabouts!!!! Just checked... 1mm = .0393700787!

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Hi Guys

Here`s Gormo as predicted........with some thoughts on the above.

Firstly, one thing I should point out, because I think it is quite important, and I should have covered this from the very beginning............is that I " don`t" remove the springs from my points. Some of my points have springs and some don`t.......I use Peco and some Atlas.........the Atlas do not have springs.

The mechanical system that I have shown in this topic will work with either, without modification. There is enough strength in the system to throw a spring loaded Peco with no effort.

Now ......Alan........the wire subject.............use any type of wire that will work and fit the point. You will find wire,that may appear to be too soft or pliable at first glance,upon closer inspection, when tested over a short length ( eg....30 - 40 mm ) may actually have plenty of stiffness in it to do the job and possibly a little springyness ( is that a word ?????) as a bonus.

I have a suggestion for you........paper clips...... I have some paper clips ( made in China....like everything )......they are the smaller variety

 

post-6075-0-13229300-1337127688_thumb.jpg

 

The wire used is approx. 0.90mm because it fits through the parts I have made.........but I don`t have a calliper so don`t quote me on the size

 

post-6075-0-06865900-1337127745_thumb.jpg

 

Once the paper clip is straightened out it offers us a length of 105mm or 5 1/8"..........enough probably for two points depending on how you attach it to the mechanism

 

post-6075-0-54368400-1337127631_thumb.jpg

 

I can`t remember now the cost of these clips but I would imagine you could get a box of 100 for about one pound. The wire used in the clip would work perfectly well in the point mechanism I am using.

So there you go lads!!!!............I hope that has been of some assistance to you

 

Cheers Gormo

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Got plenty of those paper clips Gormo... and some that are a tad bigger and thicker, fit nicely into the hole in the tie, and still have a bit of a 'twang' to them. Might be easier to attach to a plastic snake too, but I'll see if that's so.

 

Lovely photos too!! Similar ones of your lever against the measuring tape would be the icing on the cake, as that's the piece of kit that poses my greatest challenge. I'll have 30 if you go into production!!!!!!... but my brain's having a hard time trying to fathom how to attach an 'inner plastic rod' to something like it. Might one of those things called a clevis be the answer?

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Hi Alan

I`m glad the paperclip solution appears to be a winner. In respect of attaching the inner cord to the lever........a clevis would work. The part of the clevis with the hole in it could then be attached to the lever by using a track pin or something similar. The part of the track pin that protrudes through the other side of the lever can be bent at 90 degrees so that it wont fall out. If the hole in the clevis is too big, thus allowing the track pin to pass through it, use a suitable small washer on the track pin, which in effect creates a larger head on the pin. I`ll demonstrate with pics below..........The example I am showing is actually a bell crank with a rod ( modified umbrella strut ) attached and held in place by a track pin. If the rod has to be removed......simply straighten the pin and remove. I would probably use a new pin to refit the rod.

 

Pic # 1 shows the track pin securing the rod

post-6075-0-77285600-1337336660_thumb.jpg

 

Pic # 2 shows the pin being held in place by bending at 90 degrees

post-6075-0-96766100-1337336173_thumb.jpg

 

Pic # 3 Point Lever

post-6075-0-83392500-1337336234_thumb.jpg

 

Pic # 4 & 5 Sliding Rod

post-6075-0-34532900-1337336300_thumb.jpg

post-6075-0-25815400-1337336367_thumb.jpg

 

Pic # 6 Lever Frame Spacers

post-6075-0-81806300-1337336418_thumb.jpg

 

Pic # 7 & 8 Single Lever Mock Up

post-6075-0-05798800-1337336467_thumb.jpg

post-6075-0-48962000-1337336513_thumb.jpg

 

Pic # 9 & 10 Four Lever Mock Up

post-6075-0-93545100-1337336563_thumb.jpg

post-6075-0-86419200-1337336613_thumb.jpg

 

I hope the above is of some assistance.....................Cheers Gormo

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Hi Gormo... and I have to say, without a shadow of doubt, all those close-up pics are of GREAT assistance!

 

Bought a range of those snakes this morning as well as four sizes of those choc block things. The clevis things that came with a couple of the rods will do the job of linking to the lever without a problem and, as for the lever, at least I know now exactly what I'm looking for. Found a local source for those nyloc nuts and washers too, so it's all coming together nicely!

 

Anyway, got things to play around with now, and will let you know how I get on.

 

What's amazing (to me at least!) is that this discussion originated from Australia... and took in 'the States' along the way!

 

Very best wishes

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Hi Gormo... and I have to say, without a shadow of doubt, all those close-up pics are of GREAT assistance!

 

Bought a range of those snakes this morning as well as four sizes of those choc block things. The clevis things that came with a couple of the rods will do the job of linking to the lever without a problem and, as for the lever, at least I know now exactly what I'm looking for. Found a local source for those nyloc nuts and washers too, so it's all coming together nicely!

 

Anyway, got things to play around with now, and will let you know how I get on.

 

What's amazing (to me at least!) is that this discussion originated from Australia... and took in 'the States' along the way!

 

Very best wishes

 

Hi Alan

Sounds like you`ve got a full head of steam and you`re about to leave the platform.......Good Luck with your system.

I agree about this topic........it`s become a world topic thanks to the internet. This site is one very good example of how the internet is useful for the sharing of knowledge and bringing people together........Keep up the good work Andy..!!

Cheers Gormo

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I think I understand your comment ELTEL... but the whole idea of manual operation is, for my part at least, to save a whole lot of money... probably around £300 on 25 points. What's more, though, I do like the idea of 'throwing a lever' instead of 'pressing a button', but then I'm old fashioned I suppose.

 

Come to think of it though, I'm not so very sure adding point motors is that much of an easier option. Depends on how manually dexterous you are!

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