Help with turnout operating mechanism required.

[eboricum]

Hi all.

I am in the process of building my first O gauge layout, a shunting plank. I only have three turnouts but I have constructed these with C & L chairs, crossing timbers and steel rail and using Templot to design the track plan on a  2.2m baseboard. I had to use A6 turnouts to fit. Three Tortoise motors from a previous EM layout were placed under the baseboard after replacing the steel operating wire, which is around 22thou, with 28thou. JLRT tie bars were soldered to the rail to give a throw of 1.5mm. All was good until I operated the Tortoise. The blades did not throw right over in either direction. All of the turnouts performed in the same way when attached to the tie bar. The only conclusion I have come to is that the steel rail is not bending sufficiently to close the blades and therefore the Tortoise motors are not strong enough to cope.

I did use Peco PL10's on a previous EM layout together with an homemade baseplate on which to mount a micro switch and Z spring to take up excessive travel. Not having used Peco motors for 15 years I'm not sure of the throw they give or whether they would overcome the steel rail problem. I would be grateful for any suggestions.

Allan

[daifly]

28thou wire is almost certainly too lightweight for the job.

0.8 or 0.9mm piano wire or similar is generally considered appropriate for moving 7mm scale switch rails.

Dave

[Simond]

Sounds like some nice work.  Pictures please!

 

I agree with Dave, you’ll need something a bit stiffer.  
 

I presume your blades sit pretty much equidistant from the stockrails with no force applied?

 

atb

Simon

[Stephen Freeman]

All depends on how stiff the blades are. If they are too stiff no motor will do it. Assuming the blades are not too stiff then try adjusting the throw on the Tortoise/use stiffer wire. Blades should be sprung against the stockrail before fixing the stretcher bar(s).

 

Are you sure you meant to say a throw of 1.5mm?

[eboricum]

Hi Dave. I think I'll try that before changing motors. Must admit I thought 28thou would be enough but obviously not.

Allan

[eboricum]

Hi Simon. I've attached a couple of pics of the turnout. As you can see, the 1.5mm flangeway gauge is in place and just holds the opposite rail closed. Forgot to mention that I've gone for 31.5mm track. The second pic shows the Tortoise motor disconnected.

Regards

Allan

[eboricum]

Hi Stephen.

Now I've removed the motor I think the blades should be ok with the stiffer piano wire. The crossover has two stretchers so it appears I have missed one off also it looks like the joint is coming adrift. (cheap superglue). Perhaps we should all take more photos.

Regards

Allan  

[doilum]

Not sure how thick your baseboard ply is, but inserting a 3mm piece of packing on top of the tortoise will increase the leverage and throw.

[eboricum]

Hi Doilum.

The ply is 6mm  birch faced with 3mm cork. Is that inserting 3mm packing in between the motor and baseboard?

Allan

[meil]

You should not be attaching the Tortoise directly to the baseboard in any event. If you look at the base of the Tortoise you will see it is slightly bowed. By attaching it directly you are in danger of failing the attachment lugs. You should use some sort of stand-off so as not to stress the attachment lugs.

[Michael Edge]

I've fitted somewhere between 450 and 500 Tortoise motors now, all screwed directly under the baseboards without any failure of the lugs.

[doilum]

11 hours ago, eboricum said:

Hi Doilum.

The ply is 6mm  birch faced with 3mm cork. Is that inserting 3mm packing in between the motor and baseboard?

Allan

That was my idea. It allows you to play with the laws of leverage. This is of course a trade off, longer lever wires allow wider movement but at the cost of more flex and decreased force. I have used 0.9mm wire from Eileen's.

[Michael Edge]

I use .8 or .9 piano wire for facing points in 4mm (in many of the locations I have fitted them they are not powered in the normal position), the wire provided with the Tortoise is really inadequate and certainly for 7mm.

[eboricum]

Hi Doilum

Thanks for that. I'll check Eileens out.

Allan

[eboricum]

Hi Michael.

After checking Eileen's it appears they sell .8 or 1mm so I think I'll get a couple of lengths of each to try.

Allan

[Nicktoix]

On 14/04/2021 at 21:13, eboricum said:

Hi Simon. I've attached a couple of pics of the turnout. As you can see, the 1.5mm flangeway gauge is in place and just holds the opposite rail closed. Forgot to mention that I've gone for 31.5mm track. The second pic shows the Tortoise motor disconnected.

Regards

Allan

Yor flangeway gauge is not suitable for setting switches . The throw is substantially more ,something like 4.75 inches which scales up at just under 3mm in 7mm scale. 

The flangeway gauge is for setting the gaps around the frog and not ideal at that.

Nick

 

[eboricum]

Hi Nicktoix.

Will check that. The Dapol 08 runs through ok but not tried wagons or the Bachmann brass 04.

 

[melmerby]

A motorised but not stall motor type machine might give you more leverage.

e.g. https://www.dcctrainautomation.co.uk/mp1-point-switch.html

 

These have more leverage than a Tortoise, the actual throw can be adjusted, but a flexible operating wire will still be needed

[eboricum]

Hi All.

Thanks for all the info. Called in at a model shop in York today and found they had 1.19mm piano wire, a bit OTT but bought some anyway. One of the staff had just moved from P4 to 7mm and was using Cobalt point motors off of his old layout. He had to 'beef up' the wire so I have  attached the motor to an Exactoscale base plate, which I had, and replaced the wire with the 1.19mm. Everything is now working ok so once again thank you all.

Allan

[Nicktoix]

On 17/04/2021 at 20:47, eboricum said:

Hi Nicktoix.

Will check that. The Dapol 08 runs through ok but not tried wagons or the Bachmann brass 04.

 

I speak from experience having made the same mistake and the having to adjust all the turnouts after painting and ballasting . Easier to do it now than later.

Nick