A Roundhouse SR&RL joins the battery locos

Getting the enamel wire through the handrail and then down by the post is not a job I particularly want to do again :D

You may just be able to see it exiting the handrail and following the handrail post to the base
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Rhos Helyg Loco Works said:
In the previous front-on picture, are those wires and a resistor I see inside the smokebox? If so, how do you envisage protecting them from the gas burner?
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Hi Tony! I hope you're keeping well.

The plan is to insulate the LED wires inside the smokebox with kapton tape which should bring the heat resistance up to that of the enamel wire - 400C. The resistor I intend to move back to the cab, for simplicity.

I'm hopeful that this, together with the precaution of keeping the wires as close to the front of the smokebox as I can, should mitigate against the radiant heat in the vicinity, although I admit I am guessing at it all.

On a related note, I do have access to a FLIR camera. Once it's all back together, I'll make a video of it running. It should be quite interesting to see a thermal video of a loco in steam.
 
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Hi ... Yes, all good here, thank you.

Well, all I can really say is: Good luck with that! With the gas burner sending its hot gases and flames to the front of the smokebox, as it is designed to do, it is an area that gets mightily, mightily hot. I don't know the temperatures involved as I've never measured them, but it would seem to me like holding wires in the flame of a gas blow lamp. That tape must be good stuff!

On the occasions when I have wired the lamp on a steam loco I have always run them over the outside of the smokebox.
 
Forget the tape..
If there is the slightest hole, between smokebox and lamp.. Forget the lamp!

I am also of the opinion, unless you silver-solder your wires, the joint(s) will fail, even irradiated insulation, will not stand the temperatures.. - I m not sure about silicone insulated wires?

All-in-all, I do not think this lighting arrangement will work? At least, not for very long.. :(
 
Thanks for the words of warning all. It sounds as though an external conduit might be the best approach then. That will be a shame. I'll hold off wiring it until I've at least had the chance to check the temperatures in the area.

I'm perplexed as to the warning about the smokebox hole though. The smokebox appears mainly decorative; it's formed of 1mm brass and has plenty of holes in the design. I can't see how my 0.5mm addition impacts it20200807_101933.jpg

Here's the part removed from the loco. Am I correct in referring to it as the smokebox?
 
On Ali express/china bay you can get a very fine insulated wire 0.5 that is heat resistant.Buy a 1metre sample$1.49US and run positive wire down copper use copper as earth. you could lay wire on top of boiler smoke box to look like conduit, from handle to light as they would of on real loco. They were a little messy up there with any wiring so could be made to look photo typical with a bit of artistic license
 
Maybe a silly question, but the on the model and the prototype it looks like there's a Stones generator behind the light, suggesting the headlamp would be electric? Where did they run the wires on the prototype? Assuming that there would have been some sort of control for the lights in the cab. Or might it have been as simple as turbine on, light on?

It might be easier to find some suitably sized wire, that would look to scale being routed externally, rather than finding some that can live in a gas burner?
 
musket the dog said:
Maybe a silly question, but the on the model and the prototype it looks like there's a Stones generator behind the light, suggesting the headlamp would be electric? Where did they run the wires on the prototype? Assuming that there would have been some sort of control for the lights in the cab. Or might it have been as simple as turbine on, light on?
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If typical of most US steam locos, the generator would have run pretty much continuously as it would also have provided power to various other lights around the loco, principally in the cab. It has to be remembered that a full-size loco is invariably a lot cooler than one of our models simply due to good insulation, so there would be plenty of suitable routes for wiring.
musket the dog said:
It might be easier to find some suitably sized wire, that would look to scale being routed externally, rather than finding some that can live in a gas burner?
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As I said, that is exactly what I did...
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Point(s) taken, I'm rebuilding the Roundhouse headlight and generator to run the wire on the outside of the smokebox in a conduit :)

For interests sake I will take some temperature readings of the smokebox to see what it gets to. I'm curious to know.

Work has been slow and steady. Its starting to come together but there's a fair bit left to do.

Waiting on some parts from DJB and Locoworks in order to finish the steam chests and tender. I'm now working to finish the cab and to make an air tank/pipework for the tender, plus finishing the running boards and headlight

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The tender now has an air tank, formed by wrapping thin styrene sheet around some aluminium rod and dunking it in boiling water to take the shape
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The walkways have had the tiniest sliver of brass sheet added as edging and the annoyingly exposed screw on the top of the bell has had a brass rivet head put on the top to finish it off

I'm trying to decide whether the sand domes should get brass bands. The picture below shows a very loosely rigged up band to see how it looks. Im favouring the look of it at the moment, together with some boiler bands perhaps?20200813_165529.jpg
 
DGE-Railroad said:
Thanks for the words of warning all. It sounds as though an external conduit might be the best approach then. That will be a shame. I'll hold off wiring it until I've at least had the chance to check the temperatures in the area.

I'm perplexed as to the warning about the smokebox hole though. The smokebox appears mainly decorative; it's formed of 1mm brass and has plenty of holes in the design. I can't see how my 0.5mm addition impacts itView attachment 271256

Here's the part removed from the loco. Am I correct in referring to it as the smokebox?
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Yes it is a smokebox and yes they have quite a few holes. The flame Will have lost some of its momentum and heat by the time it gets to that smokebox but not a lot. On my RH Jack heat managed to get out below and cook the nylon gear on the SloMo so do not underestimate the latent heat around in that area. If you do not believe me very carefully touch it when in steam, if you linger you will get a nasty burnt finger.
 
A pretty little coal hatch from Locoworks adds some more detail whilst covering up the old receiver switch hole nicely20200819_153234.jpg
 
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A few boiler bands have been added. Now I need to add some steps and get on to finishing off the cab.

It'd be fair to say I've learnt a lot from doing this, particularly working with brass which has been a steep curve and something I still have a long to way to go with. Investing in a copy of Simon Boltons excellent 'Scratch Building Model Railway Locomotives' has been valuable and inspiring in this respect!

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I think I'm going call it a day on the cab and get it painted

It's eaten into a huge amount of time as it's my first foray into the world of brass building but the result is passable and I'm going to quit whilst I'm ahead. I need a break from it :D

I decided to pick up a copy of Simon Bolton's 'Scratch Building Model Railway Locomotives' and I'm glad I did; well written, informative and motivating (although he does make his own incredible work sound sickeningly easy)

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