Hole in tiebar for point motor

[philsandy]

I have just received 10 points from Marcway. I was going to use a mechanical device to work the points (push pull rod), as most of the points are close together and it's a small layout, but it seems they need a self locking point motor to operate them.

Can they be operated mechanically? I'm begining to think it might be worth the extra expense and use motor drives. 

Done some research into Cobalt and Tortoise motors and it seems the Tortoise is the more reliable and popular of the two.

 

There is no hole in the point tiebars for motor operation, is it just a matter of drilling a small hole in them, and what size?.

I'm  a little nervous about drilling into such a delicate piece of trackwork, is there a technique to doing this to put as little strain on the point while drlling.

 

[kandc_au]

Why can't you use a slide switch or am I missing something here?

It will lock the point either side.

 

Not familiar with Marcway points so cannot comment re holes.

 

Khris

[RJS1977]

Not familiar with Marcway points either but the easiest way to get the size of the hole is to buy a point motor....

 

I would have thought that if the point was on a flat surface and secured well enough (use Blu-Tak to temporarily secure the tie-bar itself!), there shouldn't be an issue with drilling the hole in the tie bar as the surface underneath provides an equal and opposite pressure.

[Black Sheep]

I believe that Mercontrol wire in tube systems do lock the point in place and it is possible to do it using a home built system.

[Norm81]

My suggestion would be to use a small drill bit in a pin vice and do it by hand. Might take longer but should be neater and you've full control over how much pressure is applied to the tiebar.

[66C]

I would strongly recommend NOT drilling a hole in the tie bar. A more robust solution that will not weaken the tie bar is to clean the paint off and solder a small loop of brass wire for the operating wire. The loop of brass wire does not have to be in the four foot - put it at the end of the tie bar away from the viewer and the operating method will then be less obtrusive.

 

Manual operation does need something to hold the blades at each end of their travel. Consider using a servo crank underneath the baseboard with a compression coil spring (ex-biro?) on a pivot to provide the over centre action.

 

If you decide to use Cobalt or Tortoise motors, you WILL need heavier spring wire than is supplied with the motors for Marcway turnouts - I speak from experience.

 

Regards.

[philsandy]

Thank you for all your replies.

 

I've had  a look at Mercontrol and it looks quite good. But am I right in thinking that even if you use a mechanical method of point operation you still need some electrical switch device to alter the frog polarity?, (I'm going to be using DCC).

If this is the case is it not just easier, albeit more expensive to use motor drives?

 

66C, Re soldering a loop of brass wire to the tiebar, what gauge of wire would you recommend?

[hayfield]

Thank you for all your replies.

 

I've had  a look at Mercontrol and it looks quite good. But am I right in thinking that even if you use a mechanical method of point operation you still need some electrical switch device to alter the frog polarity?, (I'm going to be using DCC).

If this is the case is it not just easier, albeit more expensive to use motor drives?

 

66C, Re soldering a loop of brass wire to the tiebar, what gauge of wire would you recommend?

There are small microswitches where the switch are can be activated by the Mercontrol wire depressing the arm on the switch, very simple, cheap and effective. Also GEM point levers lock both ways

[BRealistic]

Don't know whether you've come across this thread, philsandy, on manual point control...

 

http://www.rmweb.co.uk/community/index.php?/topic/54069-manual-point-control/

 

but it might be worth a read.... particulary about the way the point blades are held in place. This is done simply and easily using Nyloc nuts and washers to hold your 'point lever'. They have been proven to have sufficient friction to hold the lever... and the point blades, so no 'additional' locking device is required... and the tension applied by the nuts is adjustable. I used them to make a mock-up and they work just fine.

 

And on the matter of changing frog polarity, you could consider using a couple of 'hex frog juicers'... which have also been discussed on various threads. That's my intention, anyway!

[66C]

Thank you for all your replies.

 

I've had  a look at Mercontrol and it looks quite good. But am I right in thinking that even if you use a mechanical method of point operation you still need some electrical switch device to alter the frog polarity?, (I'm going to be using DCC).

If this is the case is it not just easier, albeit more expensive to use motor drives?

 

66C, Re soldering a loop of brass wire to the tiebar, what gauge of wire would you recommend?

For my own hand-built turnouts I used 0.5mm brass wire - very discrete when used at the end of the tie bar.

 

There are several options for switching the polarity of the frog. If you have an under-baseboard linkage, you could use a microswitch - these are relatively cheap at less than a Pound each. Another possibility is to use an electrical switch that also operates a mechanical linkage to move the tie bar.

 

Motor drives are the easy option - from those mentioned so far I would recommend Tortoise but their only downside is that they are quite deep - have a look at their website for installation information. Details at:

 

http://www.circuitron.com/index_files/Tortoise.htm

 

Regards.