Northumbrian Build Thread

[RLWP]

I'm not familiar with this particular design, where does the exhaust come out of the block?

It's worth knowing that steam engines run far better on steam than on air, so however it runs now, it will be better with the boiler. Careful thought and perseverance will see you through here

Richard

[steam4ian]

Pete

Shawki has said it all!

my guess; a tray to catch the embers when the fire is dropped at the end of the day.

Cancelled todays public run as per instructions only to find temp only got to 33 degC.

A bit cheesed off. a mate was bringing his second loco today for me to drive all afternoon.
Ian

[jma1009]

we dealt with the loose eccentric advance some considerable time ago.

i would disconnect the axle pump to start with... or at least remove the cap on the inlet before running on air!

i use singer sewing machine oil for running on air as it doesnt break down as an oil film with condensed water from a compressor...though in the current heat you aare experiencing this might not be a problem as i suspect air humidity in virtually non existent!

im also pondering where the exhaust escapes!

cheers,
julian

[peteh]

OK - I seem to have poorly stated the 60% power - I was trying to say I only have 60% ( 2 lots of 30%) of a revolution powered, then it is fouling somehow and stopping. Have tried running it without the guide bar bracket which certainly added a lot of freeing, so will need to fine tune those. My suspicions at the moment are either the valve rod lengths or the connecting rod lengths. Tried swapping connecting rods but no appreciable difference.

Both stop collar set screws are approx 180 degrees from the crank, which gives me the best piston movement on each side, and both valve cranks are set also at 180 degrees (by eye). I guess I am up to around 6 hours of fiddling on this at the moment - but after all that is the fun of this hobby.
I have found (in no particular order)

• slight under trim of lower steam chest gaskets which raised an edge of the valve - permanent exhaust, both cylinders.
  
• mismatch of power strokes (not at 90 degrees to each other)
  
• over tight crosshead guides as brackets not absolutly right.
  
• various other tight areas in vavle guides/glands, cylinder glands
  

- all of which have been rectified.

Sorry guys - not a beer shelf as I can't drink the stuff, but close enough. It's a shelf to put my tea on when working at the station on public run days. Will slot between the warning signs on the water stands to keep my tea off of the ground. Been talking about making one of these for over a year now

For those asking the exhaust comes out of the top of the steam chest on the body side - I havn't worries about making those parts yet. Well thanks to the weather I didn't quite make it to the running on air stage, although I feel that I am closer than this morning, a little more driven arc and a lot more power within the arc.

Pete

[RLWP]

Jan 6, 2013 12:20:32 GMT peteh said:

{snip}both crank pins are set also at 180 degrees (by eye). {snip}
Pete

I hope that's a typo - set at ninety degrees

Richard

[doubletop]

Jan 6, 2013 13:03:53 GMT RLWP said:

Jan 6, 2013 12:20:32 GMT peteh said:

{snip}both crank pins are set also at 180 degrees (by eye). {snip}
Pete

I hope that's a typo - set at ninety degrees

Richard

That would explain a lot.........

And Julian's point about the water pump eccentric. Also set it so that the pump piston is being driven into the pump on the forward strokes of the two pistons. That's when you get more power as there's no chance of any gland leakage reducing power when on the forward stroke. The reduction in piston size as a result of the piston rod is probably not material.

Pete

[peteh]

OOps valve cranks
Axle pump is currently disconnected as per suggestions (just hadn't mentioned it)

[peteh]

Club run day today so only a little tinkering this week. I have been mainly trying to eradicate as much friction as I can. By judicial filing I have minimally reduced the crosshead guide rod lengths and have so far substantially reduced a lot of my friction problems. Next stage is to get a valve for my compressor so I can get more than 15 PSI to the valves, I have a reasonably 'leaky' set up that was put together for the initial test and I am losing much pressure to it.
I am also thinking of checking the O-rings for the pistons and replacing with packing and also repacking the valve/piston rod glands to make them more airtight after the current running in.

I am certainly getting more 'oomph' to the piston movements so am on the right track I believe

[RLWP]

15 psi? I'm surprised it will even try to run at that pressure on air as a new engine

Richard

[peteh]

Hi Richard - I got similar comments from the club guys as well - maybe I've made a better job of it than I think !

[doubletop]

Pete

Can you turn it over by hand at all? It should be pretty stiff

I'd leave the O rings as is and go round with soapy water and find the leaks and deal with them. Then give it lots of oil and at about 40 PSI to get it to start, even 60psi for the initial inertia. Then get it to run for an hour or so and keep the oil going. Pretty soon into the run you should be able to reduce to 25psi then further.

Then, and only then, consider using a file to loosen the tight spots.

Just aim to get below 10psi for now. It will be a completely different beast on steam.


Pete

[peteh]

Hi Pete,

Yes I can turn it over by hand (with some stiffness), could do that before the weekends fettling I have been using heaps of light oil for all of my attempted runs, including into the air inlet / steam chests. My main leaks are actually in my compressor to locomotive links (via water separator) - incorrect threads etc. Will have to sort out properly next weekend

[peteh]

;D ;D ;D ;D

Says it all really - runs well. Once I got the pressure up to 60psi the Northumbrian just started. Now running easily at 40psi and easing by the second Video has been taken - see link

youtu.be/7vVmGzOczFM

You can't tell but the axle pump has been reconnected as well

[peteh]

Just re read Doubletops comments - dead on with your indication of pressure required. Not getting too much shed time as still pretty hot and humid but today I just don't care

[Shawki Shlemon]

Running on air ( very nice ) Today , on steam soon , good luck and well done .

[peteh]

Thanks Shawki,
Hope you are staying safe and cool over in Sydney.

[Deleted]

Well done Pete... she looks good and as Shawki said, 'she'll soon be in steam'..

Pete

[peteh]

Thanks Greenglade,
Not sure of your definition of 'soon' taken since October 2011 to get this far Still, make one piece a a time and and some point it will get finished

[jma1009]

well done pete!
excellent! quite a magic moment, and hope you are well pleased with all your hard work!
i was 18 when i achieved the same moment on my first loco, but still remember the feeling and excitement very well!
cheers,
julian

[Jim]

Well done Pete,
It is indeed a magic moment when you see all your hours of careful work coming together to do what you meant it to do. A great tribute to you workmanship.

Well Done

Jim