Neil Robinson
Registered
I have known a loco with both safety valves lifting fully but the pressure gauge over the red line and still rising! Needless to say I acted swiftly, it was an oil burner so no trouble to turn down the fire.
New Dora Owner needs help!
- Thread starter Phil_Vincent
- Start date
Fred2179G
Registered
Neil, you are confusing things, as that clearly wasn't a "G-scale" locomotive. I've never seen one with a red line on the gauge, let alone an oil burner. I'm sure the Dora won't have that problem.
Isn't that the so called famous Squeaky Bum Time?
JimmyB
Now retired - trains and fishing
The red line on the pressure gauge, at boiler pressure is 16mm society requirement, all roundhouse locos have a red line!!
But the Dora has no pressure gauge
Oh dear, bang bang bang went the Dora.
maxi-model
UK/US/ROW steam narrow gauge railways 1:1
You have got me looking at my live steam loco roster Jimmy. Neither of my Roundhouse Darj's, one 12 years old the other bought new in the last year have any "red line" or any other means of differentiation shown on their pressure gauges' calibration. Likewise my Accucraft US Fn3 live steam locos. However, of my Accucraft UK branded models, bought over the last 15 years and presumably manufactured in the same factories in China, only one is fitted with a pressure gauge marked with red printed calibration sector - a W&LLR Countess, and only in the 70 - 80 psi range. The rest of the UK models are not marked with any sort of "red zone" warning. All the locos, to the best of my knowledge, are not "grey" imports, apart from my K-28, and are UK sourced from new - so that should rule out any differing regulatory demands in diffferent sales territories.Yes but my response was toFred2179G comment "wasn't a "G-scale" locomotive. I've never seen one with a red line on the gauge"
As a little point of note - While the provision of a safety valve on the Dora seems to be an optional extra down under, in the UK it is listed by the importer as a standard fitment. So, it begs the question - what are the safety regulations and how do they differ, if at all, in the various territories these products can be marketed and operated in ?
I have never been aware of the 16 mm NGM stipulation for a "red lined" pressure gauge nor have I ever been challenged at any steam up over the years. It reminds me about the regulations on boiler testing that only actually applies to boilers over a certain size/volume and is there to satisfy public liability concerns for insurance purposes when held at bona fide public venue rather than private locations (I have probably got that one wrong over the years
) Let the debate commence 
MaxP.S. Looking around a couple of shops offering aftermarket 3/4" pressure gauges, for our hobby, none of them have any "red zones" marked up. I really must get a life
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In 16mm circles the red line is usually added during the boiler testing process, immediately after the hydrolic test so that when the live steam test is done there is a reference to the blow off pressure of the relevant locomotive. This way the pressure gauge can be adjusted if required to match said red line. All of my Roundhouse Locomotives have that red line.
maxi-model
UK/US/ROW steam narrow gauge railways 1:1
So, from what you are saying Jon, we are agreed that the "red line" on a pressure gauge is one that is generally added subsequent to a boiler test, advised but not mandated by the 16 mm NGM - Calibration 1.2., boilers under 3 bar litres. The marking is not generally required or supplied on a newly manufactured loco prior to purchace. It is the product of this test,or similar, if carried out. I can see why a manufacturer might not apply it - duplication, cost and legal implications spring to mind. Hence the fact some of us might not be familiar with this additional form of calibration on our live steam loco pressure gauges. As I said I have never been challenged nor requested to have this marking showing or evidence of any form of boiler test when running at any local 16 mm NGM group meeting in the past 15 years.
I'm not saying it is unnessesary. Probably highly advisable with a hard working live steamer at some point in its life. But locos offered for sale, new or otherwise, do not seem to be required to have it done and so marked by any trading law. A lot of owners may not be members of associations like the 16 mm NGM that offer the guidance for these tests. Or if they do do not bother to investigate, like me. I live and I learn, as my dear father used to say. Well, it made me go and look it up
MaxP.S. My Accucraft and Roundhouse locos were supplied with a test certificate for boiler and gas tanks when new. I always keep,all documentation supplied. They would seem to be under no compunction to add the "red line" form of verification to record both test equipment and the loco's own pressure gauge are in accordance.
I bought my Dora in England about 7 or 8 years ago, it certainly doesn't have a gauge, whether or not the newer ones have I'm not sure. It's never been an issue to me as I go by the pressure valve lifting
Fred2179G
Registered
I think it's the pressure gauge that is optional. I have never seen or heard of a live steamer without a safety valve.
Neil Robinson
Registered
Apologies for any confusion Fred. I didn't wish (and still don't) to give full details. I do wish to encourage a sensible sense of caution when dealing with any live steam equipment.
maxi-model
UK/US/ROW steam narrow gauge railways 1:1
I am referring to the safety valve, not if a pressure gauge is fitted Paul. Sorry I got mixed up about the extra cost for the pressure gauge the OP stated in his first post It does seem strange though - How do you know the safety valve is set correctly, unless you get it independently tested, you have the right equipment to hand or have a pressure gauge fitted, that is correctly calibrated ?
Max
Absolutely right Mad, we often found with testing that preasure gauges were and can be out ot their requireed setting for the Loco in question. These days steam tests do not appear to be mandated by the 16mm other tha the annual self test. Whilst none of mine have been tested for getting in a decade or more now, I never and will never take them to a public place unless they were tested. As for the red line you are also right, so far as I know it is only a 16mm and perhaps othersociety thing.
Phil_Vincent
Registered
Yeah and the manual for the Dora says to wait until you see steam from the safety valve before you run the train, so I feel like they're implying that'll be fine.
Still haven't gotten around to ringing Argyle yet. Too much on at work. Will report what they say re steam oil grade.
Still haven't gotten around to ringing Argyle yet. Too much on at work. Will report what they say re steam oil grade.
You'll be fine, the instructions also say to leave the regulator open so it will move on its own accwhen the pressure is right. I've not tried that as any distraction could lead to disaster. 460 is the steam oil you need
Phil_Vincent
Registered
Well, in my never end set of failures with this Dora. Is now I think the gas hey is blocked. I went to fire her up today and started with usual hiss and then roaring blue in the firebox then just went out and no more hissing. I've taken the gas assembly apart from the gas tank to the jet and as far as I can tell it's all clear until the jet, which only released a very small amount of gas.
Any tricks to clear the jet or is it a new one required? Seems pretty shonky to have to do that after two runs? Or is this par for the course?
Any tricks to clear the jet or is it a new one required? Seems pretty shonky to have to do that after two runs? Or is this par for the course?
maxi-model
UK/US/ROW steam narrow gauge railways 1:1
First - Do not attempt to clear the jet with a pin, you will wreck the broaching of its fine pin hole aperture. Blow a jet of gas back through it instead. Then you can also clean the jet in some cellulose (lacquer) thinners if that does not work. Insert a small piece of blotting paper, rolled up, into the jet 's housing to help catch any stray debris and stop it getting lodged blocking the broached jet hole in the future.
You might want to clean the gas tank with some thinners too. These Chinese manufactured locos are notorious for debris, like flux, being left in the gas tank only to detach and block the jet later - multiple times. Don't ask me how I know
Be sure to burn off any excess thinners residue and vapor before reassembling the system. Consider replacing the jet with a better quality manufactured one. My local Accucraft service agent would replace the ones in my Accucraft locos (not Roundhouse, all UK made 
) as a routine measure - Try The Train department The Train Department - Small Scale Live Steam Locomotives and Steam Accessories - Home in the US for a new better one - probably a Ronson #5, as they are known here in the UK.
When reassembling the gas system always use some PTFE tape on all the threaded joints to stop any unnecessary minor leaks that may impact the designed performance and integrity of the gas system. Make sure you do not allow any stray bits of the tape to cause any further debris incidents if it breaks off into the gas flow. Finally, store your gas cans upside down and give a quick squirt to clear any debris that has fallen into the nozzle before filling. And check your gas filler valve is working properly.
Bit of a brain dump ? But all standard practice when you get into these "small" gas fired locos. Took me a while to learn all that and I am still learning 15+ years on. Oh, and if you have an active local garden railroad group, operating live steam, join in. A great way of gaining practical experience - as well as on here Max
You might want to clean the gas tank with some thinners too. These Chinese manufactured locos are notorious for debris, like flux, being left in the gas tank only to detach and block the jet later - multiple times. Don't ask me how I know
Be sure to burn off any excess thinners residue and vapor before reassembling the system. Consider replacing the jet with a better quality manufactured one. My local Accucraft service agent would replace the ones in my Accucraft locos (not Roundhouse, all UK made ) as a routine measure - Try The Train department The Train Department - Small Scale Live Steam Locomotives and Steam Accessories - Home in the US for a new better one - probably a Ronson #5, as they are known here in the UK.When reassembling the gas system always use some PTFE tape on all the threaded joints to stop any unnecessary minor leaks that may impact the designed performance and integrity of the gas system. Make sure you do not allow any stray bits of the tape to cause any further debris incidents if it breaks off into the gas flow. Finally, store your gas cans upside down and give a quick squirt to clear any debris that has fallen into the nozzle before filling. And check your gas filler valve is working properly.
Bit of a brain dump ? But all standard practice when you get into these "small" gas fired locos. Took me a while to learn all that and I am still learning 15+ years on. Oh, and if you have an active local garden railroad group, operating live steam, join in. A great way of gaining practical experience - as well as on here
Max
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Gas jets can and do get blocked, sometime there may be tiny bits of dust left in the assembly that inevitably get into the jet to block it. My solution has been to unblock it with a tiny bit of wire that usually pushes out the blockage, you need really fine fuse wire or a bit of fine multicore separated wire. It does need to be very fine. If this does not work then a new gas jet may be required.