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Discussion Starter · #1 ·
Hi all
Does anyone know how to do wire in the tube point operating.
What materials do you use and where is the best place to purchase it and is there a cheap way of doing it or not.
I have heard of the slippery sid type way but do not know if you can get it or not and how expensive it is hence the question about if there is a cheaper way to do this type of point operation.

Many thanks
Paul
 

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This is the most recent discussion on this topic - link. If that's not enough info, ask a question at the end of the thread to keep all the info in one place.

David
 

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Bog Snorkeller
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I use the Wire in Tube (WIT) method on parts of my layout and it has so far proved 100% reliable in operation.

I used 1/16" outside diameter tubing obtainable from most model shops in 1 metre lengths (Try the model aircraft section) and for the inner wire I obtained some very thin piano wire. GEM models do a system called 'Mercontrol' which better explains how it works than I can. http://www.gemmodelrailways.co.uk/GEM_Web_...Mercontrol.html

Two things you will have to decide for yourself.
1) How to connect to the point.
2) What operating mechanism or lever system to use.

After some trial and error, I opted for;-
1) No need to buy special fittings IMHO just put a 90 degree bend in the wire with pliers and simply push it up the hole in the middle of the tie bar. Once installation is complete and you're happy with it simply snip off the excess level with the tie bar.
Run the tubing to the point right up to the outside edge of the tie bar base. Insert a track pin into the base board either side of the tube near the end (10 - 15mm) and solder them to the tube. You can also put a pin in along the run of tubing about every 6 - 8 inches and solder to keep every thing in place. NB. When you bend the tubing make sure the wire is inside and this will prevent kinking.
2) DPDT switches mounted on top of a small plastic box. The switch contacts can be used as LED feeds or polarity switching.

My layout is covered with 1/8th inch cork and it was an easy job to cut channels to accommodate the tubing. Marked with a felt tip pen before cutting, you should aim for nice flowing curves with nothing tighter than about the size of the bottom of a 1 litre paint tin.



WITs need to be kept as level as possible and don't like being crossed over each other. Careful planning needs to be done to ensure the fan of WITs is arranged correctly. Starting with your control mechanism as a datum point find the furthest set of points to the right, this will be the right handmost lever or switch. Then go next furthest gradually working along the points towards your control mechanism making sure none of them overlap each other, until you reach the nearest points on the right which should be somewhere around the centre of your control mechanism. Now repeat the exercise going left - start with the nearest working out to the farthest. Very difficult to explain and the only example of the fan of WITs I can think by way of explanation is the shape of the Menorah (Jewish Holy Candelabra);-


Please - no offence intended.....

Biggest problem I had to overcome was joining the tubes bearing in mind that once they were set up they would be buried by scenics into their channels. Best method I found was to buy some 1/16th INSIDE diameter tubing and cut it into 1" lengths. I pushed the two lengths of WITs tubing into one of the 1" lengths and 'tacked' the ends to the tube using solder.



Explanatory Note - Using the left most switch in the above picture;-
1) The end of the WIT tube soldered to an anchorage to prevent movement.
2) The wire from the point needs to be joined to the wire from the switch. I used connectors from a choco block. These also provide a degree of adjustment.
3) To prevent bending of the wire from the switch when the point is operated, a short length of tube is soldered to provide rigidity.
4) Small hole drilled through DPDT switch knob to accept operating wire.
NB It is important to measure the complete throw of the switch and compare this with a similar measurement of the throw of the tie bar, as any incompatibility will prevent your points operating correctly - so buy the correct size of switch.

In my opinion WITs is the most reliable system of points operation on the planet with very little in the mechanism to go wrong - it's all mechanical. Like for like it's probably about the same cost as using solenoid motors but without the placement of the motors, cutting holes problems AND it takes probably more time to install. It's also difficult to install on an established layout as you will undoubtedly need to run some WITs under track work and/or scrape back your scenics to get down to the baseboard. I'd taken the decision to install the system on all viewable portions of the layout 'prior to track laying' so it was relatively easy.



Mike
 

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Just another modeller
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***Very nicely done Mike, very nice work and a really good, clear explaination!

Richard
 

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Discussion Starter · #5 ·
QUOTE (16A @ 26 Oct 2008, 08:33) <{POST_SNAPBACK}>I use the Wire in Tube (WIT) method on parts of my layout and it has so far proved 100% reliable in operation.

I used 1/16" outside diameter tubing obtainable from most model shops in 1 metre lengths (Try the model aircraft section) and for the inner wire I obtained some very thin piano wire. GEM models do a system called 'Mercontrol' which better explains how it works than I can. http://www.gemmodelrailways.co.uk/GEM_Web_...Mercontrol.html

Two things you will have to decide for yourself.
1) How to connect to the point.
2) What operating mechanism or lever system to use.

After some trial and error, I opted for;-
1) No need to buy special fittings IMHO just put a 90 degree bend in the wire with pliers and simply push it up the hole in the middle of the tie bar. Once installation is complete and you're happy with it simply snip off the excess level with the tie bar.
Run the tubing to the point right up to the outside edge of the tie bar base. Insert a track pin into the base board either side of the tube near the end (10 - 15mm) and solder them to the tube. You can also put a pin in along the run of tubing about every 6 - 8 inches and solder to keep every thing in place. NB. When you bend the tubing make sure the wire is inside and this will prevent kinking.
2) DPDT switches mounted on top of a small plastic box. The switch contacts can be used as LED feeds or polarity switching.

My layout is covered with 1/8th inch cork and it was an easy job to cut channels to accommodate the tubing. Marked with a felt tip pen before cutting, you should aim for nice flowing curves with nothing tighter than about the size of the bottom of a 1 litre paint tin.



WITs need to be kept as level as possible and don't like being crossed over each other. Careful planning needs to be done to ensure the fan of WITs is arranged correctly. Starting with your control mechanism as a datum point find the furthest set of points to the right, this will be the right handmost lever or switch. Then go next furthest gradually working along the points towards your control mechanism making sure none of them overlap each other, until you reach the nearest points on the right which should be somewhere around the centre of your control mechanism. Now repeat the exercise going left - start with the nearest working out to the farthest. Very difficult to explain and the only example of the fan of WITs I can think by way of explanation is the shape of the Menorah (Jewish Holy Candelabra);-


Please - no offence intended.....

Biggest problem I had to overcome was joining the tubes bearing in mind that once they were set up they would be buried by scenics into their channels. Best method I found was to buy some 1/16th INSIDE diameter tubing and cut it into 1" lengths. I pushed the two lengths of WITs tubing into one of the 1" lengths and 'tacked' the ends to the tube using solder.



Explanatory Note - Using the left most switch in the above picture;-
1) The end of the WIT tube soldered to an anchorage to prevent movement.
2) The wire from the point needs to be joined to the wire from the switch. I used connectors from a choco block. These also provide a degree of adjustment.
3) To prevent bending of the wire from the switch when the point is operated, a short length of tube is soldered to provide rigidity.
4) Small hole drilled through DPDT switch knob to accept operating wire.
NB It is important to measure the complete throw of the switch and compare this with a similar measurement of the throw of the tie bar, as any incompatibility will prevent your points operating correctly - so buy the correct size of switch.

In my opinion WITs is the most reliable system of points operation on the planet with very little in the mechanism to go wrong - it's all mechanical. Like for like it's probably about the same cost as using solenoid motors but without the placement of the motors, cutting holes problems AND it takes probably more time to install. It's also difficult to install on an established layout as you will undoubtedly need to run some WITs under track work and/or scrape back your scenics to get down to the baseboard. I'd taken the decision to install the system on all viewable portions of the layout 'prior to track laying' so it was relatively easy.



Mike

Hi Mike

Well what can i say that was a fantastic explantion it just requires me to digest all that information and then set about pricing it all up and also checking that i can fit it onto my layout reasonably easily.

Many Thanks Mike

Kind regards
Paul
 

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Paul Hamilton aka &quot;Lancashire Fusilier&quot;
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844 Posts
Very enjoyable and no hype either - lovely work on describing this system. Almost makes me question the "why have something mechanical when you can have it electrical" philosophy I seem to have adopted.
 

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Bog Snorkeller
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987 Posts
Thanks Guys, praise indeed.....

A couple of things I forgot to mention;-

1) Length of the WIT is important. I found, due to the throw of the DPDT switch, they do not like anything over three metres (my longest is 2 & 1/2 metres) particularly if there are a number of bends to be accommodated, as the switch throw tends to take up the small amount of slack between the wire and the inside of the tubing going round corners. This is why I had to build a separate operating box for my loco.

2) A drop of very thin oil down the tube prior to installation also helps the operation go smoothly.

On a note of interest regarding maintenance;-

I recently had to replace a fully ballasted point which I wasn't looking forward too, particularly as it had a WIT and I wasn't sure how it would react to the upheaval. The point acquired a very slight bow in its length due to a small warp in my baseboard which was derailing trains coming into the station area.

Anyone who's had to carry out this procedure will know how difficult it is to 'dig' the point out of the ballast and cut the fishplates to release it, without destroying half the layout. Needless to say I spent two days gradually chipping and scraping before it finally decided to come out and, once out, there was the end of the WIT sitting nicely on the baseboard without any damage whatsoever, dropped in my new replacement point and it worked perfectly and has done ever since.
This was no doubt due to the fact that the WITs (using this operating method) are not connected physically with the point and the hardest job apart from getting the point out was locating the tie bar hole of the new point over the thin wire sticking up out of the WIT.

Thanks again for your kind comments.

Mike
 

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Registered
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2,499 Posts
Discussion Starter · #9 ·
QUOTE (16A @ 27 Oct 2008, 08:48) <{POST_SNAPBACK}>Thanks Guys, praise indeed.....

A couple of things I forgot to mention;-

1) Length of the WIT is important. I found, due to the throw of the DPDT switch, they do not like anything over three metres (my longest is 2 & 1/2 metres) particularly if there are a number of bends to be accommodated, as the switch throw tends to take up the small amount of slack between the wire and the inside of the tubing going round corners. This is why I had to build a separate operating box for my loco.

2) A drop of very thin oil down the tube prior to installation also helps the operation go smoothly.

On a note of interest regarding maintenance;-

I recently had to replace a fully ballasted point which I wasn't looking forward too, particularly as it had a WIT and I wasn't sure how it would react to the upheaval. The point acquired a very slight bow in its length due to a small warp in my baseboard which was derailing trains coming into the station area.

Anyone who's had to carry out this procedure will know how difficult it is to 'dig' the point out of the ballast and cut the fishplates to release it, without destroying half the layout. Needless to say I spent two days gradually chipping and scraping before it finally decided to come out and, once out, there was the end of the WIT sitting nicely on the baseboard without any damage whatsoever, dropped in my new replacement point and it worked perfectly and has done ever since.
This was no doubt due to the fact that the WITs (using this operating method) are not connected physically with the point and the hardest job apart from getting the point out was locating the tie bar hole of the new point over the thin wire sticking up out of the WIT.

Thanks again for your kind comments.

Mike

Mike again thanks for the extra information it will be very helpful.
Just a thought that you made about lifting a ballasted point i always use a boiled kettle and pour the boiled water slowly onto the point and ballast and after a few seconds you can carefully lift the point off the the baseboard. Just be careful not to put too much water on.

Many thanks again
Paul
 
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