STRETCHER BARS

[murry]

Having to replace some damaged points I have come to the installation of the stretcher bars. The existing points have the connection to the stretcher bar in the centre which seems to conflict with the instructions from Ambis. Is there any reason why this could cause future trouble as these are connected to a remote unit.

[Stephen Freeman]

Yes, is the short answer.  I either add a short length of tube to stretcher bar, so that the Tortoise is mounted vertically with the operating shaft an easy sliding fit (you might find you need a beefier bit of rod), or use an Exactoscale Tortoise adapter plate and use vertical rods attached to the pointblades (preferred solution). You do need to be a member of Scalefour to obtain the latter. Otherwise you are straining the already weakened stretcher bar which leads to breakage as in this case.

 

A couple of other points if I may. The joggle looks a bit excessive and only on one stockrail. If the prototype doesn't call for a joggle then what you need is a set (see Templot club) instead on the curved stockrail.  In either case the point blades could do with a bit of refining in my opinion.

[Gordon A]

If the set up in your picture works for you then continue using it.

I tend to drive off one end of the stretcher bar with some flexibility between the stretcher bar and the remote operating unit.

This allows me to have the operating unit to be adjusted to give a bit more travel than required which ensures the blade is held firmly against either stock rail.

 

[roythebus1]

There doesn't seem to be enough clearance on the switch rail. clearance needs to be twice the check rail gap.

[Siberian Snooper]

34 minutes ago, roythebus1 said:

There doesn't seem to be enough clearance on the switch rail. clearance needs to be twice the check rail gap.

 

 

Quite agree,  the full size gap is 4 1/2 inches or 1.5mm,  but the custom in 4mm scales is to use a 20p piece as a gauge at the switch tips.

 

 

[jim.snowdon]

Another way of doing it -

 

[Nickey Line]

4 hours ago, jim.snowdon said:

Another way of doing it -

 

 

That's a vey neat solution. However, I can't help but notice that the blade tips are hanging in mid-air. They should be supported on a slide-chair.

[jim.snowdon]

1 hour ago, Nickey Line said:

 

That's a vey neat solution. However, I can't help but notice that the blade tips are hanging in mid-air. They should be supported on a slide-chair.

Yes, they should, but for whatever reason it didn't quite work out that way when I built it in situ (it is part of a rather larger assembly). Fortunately, in its proper setting, it isn't at all noticeable unless you look really closely (which the layout's viewers can't).

 

[Stephen Freeman]

On 13/12/2021 at 18:40, Siberian Snooper said:

 

 

Quite agree,  the full size gap is 4 1/2 inches or 1.5mm,  but the custom in 4mm scales is to use a 20p piece as a gauge at the switch tips.

 

 

Pretty sure that is correct for 00SF but I am equally sure that Martin Wynne has mentioned what it should be for the other gauges but I can't remember where now, though I should.

[Stephen Freeman]

15 hours ago, jim.snowdon said:

Yes, they should, but for whatever reason it didn't quite work out that way when I built it in situ (it is part of a rather larger assembly). Fortunately, in its proper setting, it isn't at all noticeable unless you look really closely (which the layout's viewers can't).

 

Actually, these days I prefer the Exactoscale units but appreciate that they are not readily available to non-Scalefour members https://exactoscale.com/track-components/miscellaneous-track-items/