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Manual Point Control


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Hello Gentlemen & Ladies

 

I have been working on a mechanical point system to go with my railway, when that eventually materialises, somewhere off in the dim and distant future.........well hopefully sooner than that??

Anyhow I have used all the tried and true methods and bits and pieces from many systems I have studied over the years. ....But one thing that made all the difference was a tip from a Victorian ( Australia ) modeller.........and I am sorry Sir but I can`t seem to locate you at the moment, so that I might rightfully acknowledge your input.......and that one thing was a modified brass hinge fitted below the baseboard with a sliding rod and a pin thru the rod up to the tie bar of the point........Brilliant !!!!!

Too much waffle from me..........below is a video that will show what has been achieved thus far.............................enjoy .......Cheers Gormo

 

http://www.youtube.com/watch?v=T8K1bgantIs

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Brian

 

Super idea,

 

If the bar that slides through the hinge was made from stiff plastic, 2 metal tubes could stick up into which 2 L shaped metal wires could drop into. The end which is not in the tube can then be soldered to the switch blade. As the blace moves across the wire can rotate in the tube, so no built up tension on the joints. You just have to drill 2 holes through the baseboard rather than make a moving sleeper

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To a complete novice like me, this looks to be a great, money-saving, idea (compared to using point motors). Please excuse these questions (if they appear daft... as I'm neither mechanically or electronically minded!!!), but doesn't the lever need to be somehow 'held' after it's 'thrown' to ensure the blades stay tight to the rails?... and... how would you go about incorporating a means for changing the polarity of the points at the same time?

 

Here's hoping this thread develops further, as the cost of buying 20-30 point motors is a big headache for me!

 

Oh, and THANKS for starting it Brian!!

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Nice and smooth - one minor modification I used on a very similar setup, is to trap an electrical switch in the 'choc block', so you can switch the frog polarity at the same time as throwing the point. I found that an ordinary 'toggle' micro switch worked well - just enough throw and a long enough 'grabbable' lever to trap between the screws of the electrical connectors.

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Brian

 

Super idea,

 

If the bar that slides through the hinge was made from stiff plastic, 2 metal tubes could stick up into which 2 L shaped metal wires could drop into. The end which is not in the tube can then be soldered to the switch blade. As the blace moves across the wire can rotate in the tube, so no built up tension on the joints. You just have to drill 2 holes through the baseboard rather than make a moving sleeper

Hi

Can`t quite follow you on this one????........

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To a complete novice like me, this looks to be a great, money-saving, idea (compared to using point motors). Please excuse these questions (if they appear daft... as I'm neither mechanically or electronically minded!!!), but doesn't the lever need to be somehow 'held' after it's 'thrown' to ensure the blades stay tight to the rails?... and... how would you go about incorporating a means for changing the polarity of the points at the same time?

 

Here's hoping this thread develops further, as the cost of buying 20-30 point motors is a big headache for me!

 

Oh, and THANKS for starting it Brian!!

 

Hi BRealistic

By using Nyloc nuts and washers to hold the point lever, there is sufficient friction in the joint to hold the lever and consequently the point blades in place. The beauty of it is that no locking device is required, and of course the tension applied by the nuts to the lever is adjustable.so you can apply just the right amount of pressure to do the job.

I have played with this prototype and shifted it back and forth at least a thousand times and I can`t break the wretched thing????

If you look at the triangular bell cranks.......that`s where micro switches can be mounted for polarity switching. I have already tried that and it`s quite effective.........maybe I`ll do another video for that...............Cheers Gormo

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That's really helpful Gormo... never come across Nyloc nuts before, but have done a search and now know all about them! How ingenious!

 

I did see the triangular cranks but wouldn't know how to add micro switches... so a video (or photo/diagram) would be great. I'm hooked on the idea!

 

Best wishes

 

Alan

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That's really helpful Gormo... never come across Nyloc nuts before, but have done a search and now know all about them! How ingenious!

 

I did see the triangular cranks but wouldn't know how to add micro switches... so a video (or photo/diagram) would be great. I'm hooked on the idea!

 

Best wishes

 

Alan

OK............I`m just charging camera batteries at the moment and I`m off out for the evening shortly.........so give me a day or so and I`ll post more info and pics........by the way the micro switch is quite effective at the end of the sliding rod too.......may be even better there?.......Anyhow......I`ll be back............Cheers Gormo
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Hi

Can`t quite follow you on this one????........

 

Some modellers dont like thick moving tiebars or sleepers, and preffer a system less obvious. 2 thin wires coming through holes in the baseboard, rather than a big thick tiebar or moving sleeper

 

Others use the method of attaching the switch blade to the tiebar via a pin bent at right angles through the tiebar and soldered to the switch blades, this redues the strain on the soldered joint of the tiebar and switch rail in operation, reducing the chances of the joint failing in operation.

 

I was just commenting on the fact that the system you are using would lend its self equally to this method of switching the turnout,

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Some modellers dont like thick moving tiebars or sleepers, and preffer a system less obvious. 2 thin wires coming through holes in the baseboard, rather than a big thick tiebar or moving sleeper

 

Others use the method of attaching the switch blade to the tiebar via a pin bent at right angles through the tiebar and soldered to the switch blades, this redues the strain on the soldered joint of the tiebar and switch rail in operation, reducing the chances of the joint failing in operation.

 

I was just commenting on the fact that the system you are using would lend its self equally to this method of switching the turnout,

Hi Hayfield

Yes I see what you mean now.........well that`s a bonus ,I had not thought of that system as a possibility. You are right of course and you have shown the benefit of this forum in the sharing of knowledge..........Thanks.............Gormo

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Hi Hayfield

Yes I see what you mean now.........well that`s a bonus ,I had not thought of that system as a possibility. You are right of course and you have shown the benefit of this forum in the sharing of knowledge..........Thanks.............Gormo

 

Its getting quite common in the UK, some build their own sliders by getting some Plasticstrut square tube, one which fits into the other.

 

The larger square tube has 2 bits 10mm long cut, an appropriate length of the other tube (though solid square rod is better ) is cut.

 

Cut a piece of 60 thou plasticard shorter in length than the thinner tube but about 3" wide. Drill a hole in each corner (these are used to mount the plate to the base board, thread the inner tube on to the 2 thicker parts and then glue the thicker tube in the center of the plate, one at each end.

 

Now you have a slider unit to attach to your wire system. Drill 2 holes 13.25mm apart for 00 (15.5mm for EM & P4) and pop in a tube in each hole, then drop in a L shaped bit of wire in each and solder to the tiebars.

 

I guess the holes through the baseboard are about 2.5 to 3mm diameter inside each stock rail where the wires are to atach to the switch rail, as there needs to be about 1.5mm movement

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There's a good description of the method I was trying rather clumsily to describe over here.. (not mine I hasten to add!)

 

http://www.westportterminal.de/manualturnout.html

 

PC01201_kl.jpg

 

Hi Mog........Thanks for the pic........that`s a good system!!.....I like the ability to adjust / set it correctly. Anyhow I have done a video as promised earlier. It shows the microswitch system and I hope it gives you guys a better idea of what I`m playing with.

 

Cheers.....Gormo

 

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Brilliant presentation Gormo. It's all so easy... when you know how!

 

Forgive my ignorance, but is it essential to incorporate the right-angle turns? In other words, would it be possible to simply run a straight rod from the lever to the hinge?

 

Thanks

 

Alan

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Brilliant presentation Gormo. It's all so easy... when you know how!

 

Forgive my ignorance, but it is essential to incorporate the right-angle turns? In other words, would it be possible to simply run a straight rod from the lever to the hinge?

 

Thanks

 

Alan

Hi Alan

Yes it is possible..........but?????.......what I have found with my experiments.......( Hey... I sound like a mad scientist !!!!! )..is that when you curve the wire and cable it creates a problem in that the wire is pushing against one side on the inside wall of the cable. It still works but it increases the amount of travel required in the lever. If you have some cables straight, some cables curved slightly, some cables curved a bit more again..........it means that each one has a different length of travel. So bring your mind back to the lever frame and what you will see is maybe one lever travels 7mm to throw the point, the next lever may travel 5mm, the next one 8mm and so on.

In the end it looks like a dogs breakfast........the straight runs of cable eliminate that problem and the wire travels the same amount over any distance. I must emphasize that this is all down to the materials I am using. If you were to use something like push bike brake cables I think it would not be a problem. The trouble is with bike brake cables that they are expensive and you don`t get the length that you require. I have successfully tested my wire through the cable over a length of eight feet. I admit the bellcranks require a lot more planning with cable runs, but the results are really good and also the cranks allow you to add on switches or operate signals or even two points with one lever.

I hope this answers your question.......Cheers ........Gormo

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:-) Great little video Gormo! For my little layouts i doubt I'll ever need bell cranks etc.. but i might just have to incorporate them just the same.. there's something very satisfying about things moving mechanically..

 

That link btw was screwy.. it's here.. http://www.westportterminal.de/manualturnout.html

 

Hi Mog,

I checked the link and that`s a great simple system.........I might have to pinch some ideas from there........Cheers....Gormo

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Thanks for the explanation Gormo. I suppose I had in mind using wire (rod) that won't bend (like maybe those metal coathangers) but thinking about it, few of my points will be exactly parallel with the baseboard front, so 'cranking' will be essential. Did you mention the gauge of the wire you've used?

 

Just so's I'm sure, can the cranks be arranged to create 'any' angle to suit the alignment of the point... which in many cases won't be exactly parallel to the baseboard front.

 

Sorry to be a nuisance!!!!

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Thanks for the explanation Gormo. I suppose I had in mind using wire (rod) that won't bend (like maybe those metal coathangers) but thinking about it, few of my points will be exactly parallel with the baseboard front, so 'cranking' will be essential. Did you mention the gauge of the wire you've used?

 

Just so's I'm sure, can the cranks be arranged to create 'any' angle to suit the alignment of the point... which in many cases won't be exactly parallel to the baseboard front.

 

Sorry to be a nuisance!!!!

 

Hi Alan

Don`t worry....you`re not a nuisance...........the wire used in the cables is 1.25mm garden wire........I think it is used to tie chicken or birdwire to a frame.......and the wire on the sliding rod under the tie bar is0.90mm and this wire has just the right amount of spring in it to work the point, and give a little at the same time.

The working range of the bell cranks is not limited to 90 degrees........it would be somewhere between 45 and 130 degrees approx. I have not measured that properly, I have only fiddled about with them in that regard........so I would suggest you experiment with that. Another thing to bear in mind is that the bellcrank shape is not limited to a triangle......I suggest you google bellcranks and see what comes up......I think I did that myself recently....???????.......is dementure setting in???????.......oh well !!!

I`ll put a PDF file on here for you with some dimensions.......it may be of some assistance to you........Cheers Gormo

 

Point Lever1.pdf

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Thanks for all the info Gormo. So helpful! Got some searching to do now to locate all the bits and pieces... starting with the garden centre just down the road!

 

John. Thanks for that link... which is useful too for getting an idea about costs... compared to 'straightforward' point motors.

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