7mm Stretching the Point... LNWR preferred

[Dog Star]

Or... how do you make your stretchers? As far as I am aware there are three suppliers of stretcher bars for those of us who make our own track... being:-

* Ambis;
* C&L;
* JLTRT.

Unless I have missed the "point", all of the listed options "turn out" to be of the flexible style of stretcher where the switch blades are joined by a vertical bar of rectangular section. Hartley Hill is based on the LNWR PW practices circa 1900 and hence the turnouts ought to have the rigid style of stretcher bar (forged ends and round bar between the ends).

Anyone know if such a product is available in 7mm? Anyone any ideas as to how to make something like the rigid stretcher bars?

thank you, Graham

 

[Rob Pulham]

Hi Graham, any chance of a photo for the complete novices amongst us? - It sounds like how I made the coupling rods on Severn may do it.

To make those, I filed a flat on a piece of round bar and soldered my flat strip to it (longer and wider than the round at the ends) to create the end bosses and then rounded the back of my flat strip so that the end result is almost round with flats on the end. I looks the part and is very strong.

 

[Dog Star]

Hi Graham, any chance of a photo for the complete novices amongst us?

Sorry to ask Robin, a photo of what? Maybe you want me to include a photo of the two main types of stretchers on the prototypes?

regards, Graham

 

[Simon Dunkley]

That, Graham, was a truly zen-like response.

to the master... (unless he be called Bo-Jing*).

*A novice once approached Bo-Jing, and asked, "Master, what is the secret of the Buddha nature?"
Bo-Jing replied, "I will share the secret of the Buddha nature with you, but first you must show your respects to the Buddha."
The novice bowed reverentially in front of a statue of Buddha, whereupon the Master gave him a terrific kick in the seat of his pants.

 

[Rob Pulham]

Sorry to ask Robin, a photo of what?

Hi Graham,

Sorry, yes please. I for one don't know what a stretcher is.....

 

[Dog Star]

OK - let us hope that this works...

GWR round / rigid tiebar

which is similar to the LNWR stretchers circa 1890-1905.

 

[Rob Pulham]

Thanks Graham,

The one at the front looks to be connected to a handrail knob at the right hand side

Not quite as I described making Severn's coupling rods then.

Does the "handrail knob" bit go right through the switch blade and locate into/pass through the outer rail - that's what it looks like to me from the photo. But I do appreciate that such things can be deceptive especially when you cannot zoom into the photo.

 

[Dog Star]

The one at the front looks to be connected to a handrail knob at the right hand side

Does the "handrail knob" bit go right through the switch blade and locate into/pass through the outer rail - that's what it looks like to me from the photo.

The photo shows a front stretcher bar and a back stretcher bar. The front bar provides the drive to the switch toes whilst the back bar goes along for the ride... well, actually, the back bar is there to ensure that the switches move as a pair and move uniformaly over the slide chairs.

The front bar is made of several parts... a forging at each end which is clamped to the switch rail, a drop link which bolts to the forging and "drops" the motion to below the bottom of the rails and a bar which connects the drop links. The forgings do pass through the stock rails and are the means by which the GWR stopped the switch toes from rising as a wheel passes along the switch.

The back bar is "loose" in the switch rails and is an one piece forging.

regards, Graham

 

[Eastsidepilot]

Graham, how about these mate, I made the master for these and they are cast in brass, the idea is that one side is insulated with some electrical wiring sleeving. Peter Hunt sells them through Perfect Miniatures, not sure of the price at present, a sprue contains three rods, one of which has an eye for the clevis on the drive rod .
We are using them on the WMR for the earlier GER points.

ATB, Col.

 

[Dog Star]

That looks just the ticket... I can see how the various cast parts fit together for the stretchers, where does the clevis for the drive rod come from?

Thanks, Graham

 

[Eastsidepilot]

Graham,
I' ll get back to you tomorrow with info mate, as I have ti sign off know, I'll get a sample to you.

ATB Col

 

[Dog Star]

Graham,
I' ll get back to you tomorrow with info mate, ... , I'll get a sample to you.

Thank you very much. Another problem which might well now be a solution.

 

[Yorkshire Dave]

..the idea is that one side is insulated with some electrical wiring sleeving

Do you use epoxy or superglue to hold ing insulated sleeve?

 

[Eastsidepilot]

Do you use epoxy or superglue to hold ing insulated sleeve?

You can use either Dave, I prefer epoxy 5 minute gives a chance to set the gap to size between stock rail and switch blade.

Col.

 

[Eastsidepilot]

........................ where does the clevis for the drive rod come from?........
Thanks, Graham

The castings come with a clevis for soldering to brass wire. A short piece of electrical sleeving is included for the insulated end which fits over the plain end, the loose end is carefully drilled through for the sleeved end to be glued in place. The fixed end is soldered first to one switch blade, I like to alternate the soldered end so both blades have a soldered fixing, hope that makes sense

ATB, Col.

 

[Dog Star]

Thank you Colin for publicising these castings and for the photographs which show how the items are assembled to form the front / back stretcher.

I have a sample of the castings and I think that the product is going to do nicely for Hartley Hill.... so watch that space for the introduction of a "bit of class" into that thread.

regards, Graham

 

[Eastsidepilot]

Thank you Colin for publicising these castings and for the photographs which show how the items are assembled to form the front / back stretcher.

I have a sample of the castings and I think that the product is going to do nicely for Hartley Hill.... so watch that space for the introduction of a "bit of class" into that thread.

regards, Graham

I'm glad you like them Graham, They are a bit fiddley to assemble but worth the effort in the end.

Col.

 

[Dog Star]

A short piece of electrical sleeving is included for the insulated end which fits over the plain end, the loose end is carefully drilled through for the sleeved end to be glued in place.

Just to make sure that I understand the method. The "free" end of the round stretcher rod is sleeved with the supplied piece of insulation material. The "loose piece" for attachment to the switch rail is drilled to accept the insulation material. Fit the sleeved end of the stretcher rod into the forging and secure with epoxy.

The stretcher rod is 30 thou OD.
The insulation material as supplied is circa 50 thou OD.
The insulation material as fitted to the stretcher rod is circa 55 thou OD.
The "loose piece" is 60 thou OD with a small hole cast into the end for the stretcher rod.

How do you manage to drill a 55 thou hole into the "loose piece" without breakout?

regards, Graham

 

[S7BcSR]

Graham
Give Dave Nicholson a bell, he has been producing GWR round insulated stretcher bars for yonks and they work a treat. They were on the S7 demo track a year or two ago.
Rob

 

[Eastsidepilot]

.............How do you manage to drill a 55 thou hole into the "loose piece" without breakout?

regards, Graham

Graham,
There should be a little more meat than that left once drilled , I'll get back to you shortly, it may be that the insulation material you have is a heavier gauge than what I have used before if you get my thinking, I'll check what I have here.

ATB, Col.