black 5 steam up failed

[Ron HancockParticipant @ronhancock63652]

[Ron HancockParticipant @ronhancock63652]

[Ron HancockParticipant @ronhancock63652]

Tried to steam today but top dome bush leaked steam so got to make a Gasket for it tomorrow.

Be nice to finally get steam up been really exited to get it up and running but due to ill health not been able to touch it for a few weeks.

Must crack on now spring soon be here time to put a few miles under her.

[David WassonParticipant @davidwasson11489]

All you need is a gasket? That should be an easy fix.

[Ron HancockParticipant @ronhancock63652]

Found the new boiler is leaking below the top dome fitted got to take back to boiler maker

Ron

[KWILParticipant @kwil]

Thought it was CE marked and properly tested,

Was it actually tested because the 2x hydraulic test should have found that! Did you witness the test?

[Ron HancockParticipant @ronhancock63652]

It is ce marked did not see the test just came with all the paperwork.

It could be some thing I have done I am going to ask if he can fit a new Top bush and re pressure test it.

I don't know how he can pressure test it without top dome fitted as hole is around 21/2 wide.

But I am a novice so anything possible

Ron

[KWILParticipant @kwil]

All openings, top dome, gauge, wash down etc have to be properly capped/covered to ensure there is a completely sealed boiler. Then hydraulic pressure is applied.

Chuck it back as "not fit for purpose" and get GB to finish the job, its not your fault it leaks, he should have found it before delivery.

Sorry you have to take it all to bits at this stage, it must p*** you off, perhaps it was too cheap?

[julian atkinsParticipant @julianatkins58923]

it is not up to GB to make a dome inner cover. they have done the hydraulic test with the dome blanked off.

it is up to Ron to make the inner dome plus all the fitted stainless bolts to suit, plus gasket if required.

i suspect the problem is distortion after silver soldering the dome bush plus use of ordinary bolts/screws. in my experience it requires a lot of fettling with engineer's blue to get a good fit with the inner dome. fitted specially made up stainless bolts make a great deal of difference – you need a plain unthreaded shank through the inner dome flange to avoid problems. i hate making up these special bolts out of stainless but is something ive done many many times.

dont expect ordinary bolts threaded up to the head to be anything like as so good!

cheers,

julian

[KWILParticipant @kwil]

julian,

Ron says in first posting above, that "it leaks below the the top dome", ie where the bush is silver soldered to the barrel.

If it was down to Ron why would he say it has to go back?

[julian atkinsParticipant @julianatkins58923]

i had commented to Ron that i would be very very surprised if the dome bush to barrel joint was the problem. if it was, then i totally agree with you.

having received further info from Ron it would indeed appear that you are right which is extremely annoying plus unusual in a professionally made boiler already hydraulically tested.

my initial reaction was it was more likely to be a problem with the inner dome to dome bush flange.

cheers,

julian

Edited By julian atkins on 08/02/2016 11:02:50

[Ron HancockParticipant @ronhancock63652]

Well after filling boiler with soapy water found bubbles coming from by the weld.

I think using the 2BA has caused the problem the top of the bush is not very deep or wide.

I have asked Goarge to make the top deeper and wider give me more meat to tap into.

I am then going to use stainless studs with nuts if I can get the stainless will make the inner dome from stainless.

Hope I am more successful next time all a big learning curve

Regards Ron

[stan pearson 1Participant @stanpearson1]

Ron

I would ask your boiler inspectore advice on using stainless as the copper boiler has different expansion rates and I was told the studs wont stay tight.

Stan

[Ron HancockParticipant @ronhancock63652]

Hi I spoke with Julian he uses stainless studs so will try the plus will locative the studs in I can't see a problem but we can only see

Ron

[Ron HancockParticipant @ronhancock63652]

[Ron HancockParticipant @ronhancock63652]

Made a new op dome out of stainless hoping I will be more successful with this one when I get boiler back fingers crossed

[David WassonParticipant @davidwasson11489]

Only 6 screws?? The inner dome on my Simplex uses 12 screws. If it is a similar diameter as the Simplex, no wonder it leaked. Probably one more screw between each of the existing screws might of worked. The screws also do not look exactly evenly spaced. Also, the surface that the screw holes are drilled through looks like there are still machine marks. If this is a gasket surface, it must be machined quite smooth.

[KWILParticipant @kwil]

David,

You are missing the point, it leaks at the boiler barrel to bush silver solder joint, not the dome joint. Certainly 12 screws, 2BA is far too large in such a narrow ring, layout, even if you do not have a dividing head is simple, using a pair of dividers set to screw PCD/2 and school geometry. Aesthetics could certainly be improved by better surfaces, but Ron admits to being a novice.

[Ron HancockParticipant @ronhancock63652]

Yes their are machine marks on the dome but it is the top as until i get the boiler back with new bush fitted cannot do the final machining till i have the correct size. He is making a larger wider bush so i can use just the top of the bush. When i get the boiler back will then fit to boiler. I can assured you it will be like Glass when its finished. The joint was not leaking after i made sure with a good Gasket and Yamaha bond that was a silicone that's heat resistant i used on Racing Motorcycles. I don't have a dividing head and maths i admit not to being that clever but i am sure next time with all the wonderful help and advice i have had will be ok I HOPE after next build.

Ron

[Ron HancockParticipant @ronhancock63652]

I have gone with stainless this time as so many private messages suggested the dome being soft metal by the studs can distort and cause a failure. With the stainless it should not warp at all just pre thinking any future problems. I HOPE

[JasonBModerator @jasonb]

Might be an idea to get him to drill and tap the new bush at least that way the boiler can be tested with all holes drilled and no risk of damaging it with subsequent drilling.

[David WassonParticipant @davidwasson11489]

Ron, do you have the drawing for this locomotive? If there was no leak at this joint, why change to stainless? What size and quantity of screw is specified on the drawing?

By the way, to lay out 6 screws on a circle, the distance between adjacent screws is half the diameter of the circle, or the radius. You do not need a dividing head, only dividers.

David

[KWILParticipant @kwil]

David,

Thank you for confirming PCD/2 = half diameter of circle = radius.

[KWILParticipant @kwil]

Ron,

When you get your boiler back from George B, please take a picture and post it here on the Forum before you start again.

[julian atkinsParticipant @julianatkins58923]

according to Ron, GB are going to fit a new dome bush to the boiler and charge him £100!

i must admit i find this very bad. up till now GB had excellent feedback from other purchasers via various contacts.

poor Ron spends a fortune on a commercial boiler. they even had the chassis to make sure all fitted but still made the boiler too short and the firebox too long so that the axlepump assembly fouls it.

the give him a hydraulic test certificate, then the dome bush to barrel joint fails.

then have the cheek to charge him £100 to put it right!

i hope they read this or get it reported to them and instead send Ron a cheque for £100 to cover the inconvenience.

cheers,

julian

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