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Post by runner42 on Jun 13, 2015 6:26:32 GMT
Thanks Julian,
today I got the Boiler Inspector to pressure test the boiler. It passed without issue, being a significant milestone I felt it was appropriate to take a picture of the BI saying "she's right mate no worries".
The next step is the accumulation test, but that's another thread.. perhaps.
Brian
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Post by ejparrott on Jun 13, 2015 8:28:22 GMT
Gordon Smith safety valve and she'll pass with flying colours!!
I recently rebuilt one of the safety valves on the club Scot and changed the spring in the other - being unable to get the valve out of the boiler to also modify that. Previously it was very much on the line for whether or not she would pass...I'm happy to say that just one valve is holding it within 1psi now. I had to tweak Gordon's design a bit too to get things to fit, because of the existing design of the body, so I'm very pleased. One day I might just make her a new pair of GS design valves from scratch
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Post by steamcoal on Jun 13, 2015 10:50:21 GMT
Well done Sir !
Been a bit of an up and down ride but you did it.
Small we fella compared to that other one on the table.
We have an Achillies boiler going together here at present and I have bought some frames and wheels for a Maisie so would be quite keen to do one myself now that there is a bit of a interest in that part of the hobby. A bit of therapy in beating out that copper after a hard week at work might do me good.
Hayden
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Post by steamcoal on Jun 15, 2015 7:20:06 GMT
Shawki.
I better dig that AMBSC code book out and check if the 3.5" Maisie boiler design complies I guess.
I still have not fitted my current Maisie boiler back on the loco so better have a good look and make some photos before she all goes back together.
Hayden
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jma1009
Elder Statesman
Posts: 5,919
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Post by jma1009 on Jun 15, 2015 8:48:05 GMT
hi brian,
very well done!
congratulations!
and think of the money you saved plus sense of achievement in making your own as compared to buying a commercial job!
cheers,
julian
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Post by Shawki Shlemon on Jun 15, 2015 9:54:34 GMT
Hi Hayden , Why are you asking me to do that ?
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Post by steamcoal on Jun 15, 2015 11:39:34 GMT
No, I am saying I will have to get the code book out.
God knows when the last boiler was built but I know at least we have the latest version of the code at the club so that is a start.
Sorry for the grammatical error Shawki. Bit casual in the lingo.( corrected version above)
H
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Post by runner42 on Jun 16, 2015 8:03:22 GMT
hi brian, very well done! congratulations! and think of the money you saved plus sense of achievement in making your own as compared to buying a commercial job! cheers, julian Hi Julian,
I had Hobson's choice with the boiler, since there is no commercial boilers available, none are licensed to build to the code. This is because the boiler has to pass stage inspections undertaken by the club's boiler inspector, so a commercial enterprise would have to present the boiler to these inspections during construction.
Brian
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Post by Shawki Shlemon on Jun 16, 2015 10:14:44 GMT
Hi Hayden , No problem , I just wanted to see what do you want me to do , however we did have in the club one of these and they are very nice and good steamers , at least the one we had in the club was . The code is cheap to buy and all is needed that you modify any part that does not comply , for example the flanges , blow down and washing plugs , water gauge position and so on , basically very little changes for example the flanges has to be a little longer , no big deal .
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Post by runner42 on Jun 16, 2015 22:42:09 GMT
Hi Hayden , No problem , I just wanted to see what do you want me to do , however we did have in the club one of these and they are very nice and good steamers , at least the one we had in the club was . The code is cheap to buy and all is needed that you modify any part that does not comply , for example the flanges , blow down and washing plugs , water gauge position and so on , basically very little changes for example the flanges has to be a little longer , no big deal . Add to that the ligament distance, that is the minimum distance allowable between tubes and flues para 3.12.1 specifies 3 mm - 0.5mm*. I have seen many pictures of boilers under construction where the ligament distance is very small due to not design but inaccurate drilling of the smokebox and or firebox tubeplates. Again that somewhat emotive topic of stay diameter and spacing.
* Dr Allan Wallace is presenting a paper to the AMBSC justifying a relaxation of the ligament distance.
Brian
PS Oops overlooked the girder stay in the crown has to be replaced by rod stays. I note that the crown is tube shaped but I assume that the firebox is not, requiring staying similar to Doris.
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Post by steamcoal on Jun 17, 2015 0:11:54 GMT
Shawki and Brian.
It is very encouraging that your discoveries are passed on via this forum so that others like me can be alerted to new information or details that may need careful consideration. Reading the code book is one thing but putting in place the changes is another and previous experience like what you have documented Brian, especially with regard to the AMBSC code is mighty helpful, if not just to change but to check in case for compliance. Although I have been an advocate for a commercial made boiler, having a friend build an Achillies boiler at present under experienced tutorship I think that with all our combined help I should be able to achieve it. It may be agreed that the Maisie boiler is one of the easier ones?
Exactly what the forum is about, thank you.
Hayden
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Post by Shawki Shlemon on Jun 17, 2015 9:32:59 GMT
Very good Hayden , I agree , remember I said " and so on " , drilling holes for the tubes is tricky because of the copper behavior , I pilot drill the tube plate and fire box front plate and then enlarge the hole by steps using the lathe , I mount the plate on tail stock ( I have welded a plate on no 2 taper and faced it and has a 3/4" counter bore on the face , you can see this on my thread cylinder boring on this site ) and use drills with taper shank mounted on the head , this way accurate holes are produced as planned .
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Post by steamcoal on Jun 17, 2015 11:42:55 GMT
Shawki.
Thanks for that procedural advice. Will look up your previous postings.
I suppose it is also a case of measure many times before cutting or boring. We do not want to end up like the 5" gauge Black 5 boiler.
hey, there is no hurry…its a hobby. Maybe if I start at mid 40's I should have it done ready for my retirement.
HB
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Post by runner42 on Jun 27, 2015 7:03:27 GMT
Just for completeness if you are building a Doris boiler to the code requirements, when you come to producing the ashpan if it is to LBSC design it wont fit as he has specified, ie the ashpan being a snug fit inside the firebox opening. The reason is that 2.5mm copper thickness on the firebox wrapper will reduce the firebox across wise opening to 1.865" (2.062" - 2 x 0.0984"). The ashpan outside measurement is 1.875" , but hey 0.010" isn't much and the copper can be teased out to that measurement. The lengthwise measurement for the firebox opening is 6.576" (6.675" - 2 x 0.0984") and the ashpan lengthwise measurement is 6.25" giving a difference of 0.326". What LBSC appears to overlook was the presence of the flanged plates for the firebox tubeplate and the firebox door plate increasing the thickness of copper to twice at the corners and intruding to a depth of 3t + 1t = 4t where t is .0984", giving a value of 0.3936" at each corner.
An aside unless LBSC had very small flanges of 0.163" then his boiler and ashpan designs are not compatible, added to that there would be openings at the front and back to allow ash to fall onto the line. The ashpan design needs to accommodate the presence of the flanged plates at each corner of the boiler and be shaped accordingly.
Because I was required to have the foundation ring all around and not at 3 sides as LBSC specified I had an additional problem of my ashpan being too long. Another candidate for the scrap bin.
Brian 
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kwil
Part of the e-furniture
Posts: 383
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Post by kwil on Jun 28, 2015 9:42:39 GMT
Always plan your work in logical steps, not just jumping about doing the easy bits just to make progress. Check and check again the drawings, make changes on copies to allow for local regulations/rules and for those improvements in techniques that have occured in the MANY years that have passed since these ancient designs were made. Good they may have been for the time, BUT BUT BUT.
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jma1009
Elder Statesman
Posts: 5,919
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Post by jma1009 on Jun 28, 2015 22:20:53 GMT
hi brian,
i suppose what KWIL means is make the ashpan after you have made the boiler and have a completed chassis!
i often see the same problem with people who make their smokeboxes and cab before making the boiler! the order LBSC described how things were to made wasnt without some logic!
cheers,
julian
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Post by runner42 on Jun 29, 2015 7:10:31 GMT
Hi Julian,
I must admit that I made the ashpan after the boiler and chassis, but still was oblivious to the changes I made to the boiler from LBSC's design. My maxim appears to be make it right the second time. But all is not lost the ashpan was easily re-worked to make it fit. I shortened it to take into account the reduce lengthwise firebox aperture and to accommodate the flanges on the firebox tubeplate and door plate rebated the corners at the top of the ashpan to allow it to be pushed into firebox. The leading and trailing edges of the ashpan now rests on the firebox tubeplate and door plate respectively. The latter point LBSC conveniently didn't address putting it down to the latent knowledge/experience of the ME to make it fit.
Brian |
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Post by Deleted on Jun 29, 2015 8:27:27 GMT
Having an ashpan which goes up inside the firebox and which is a close fit is very bad practice - I'm surprised that even an idiot like LBSC would suggest that arrangement .
Ashpans generally fit loosely around the outside of the lower firebox extensions or just sit underneath .
Ashpans warp to random shapes in use and need to have generous clearances everywhere to stop them getting jammed in place or from abrading boiler surfaces .
In any case an ashpan needs to be generously bigger in plan than the grate just to ensure proper ash collection .
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Post by Shawki Shlemon on Jun 29, 2015 9:49:51 GMT
I agree with everything RedDragon says except the description of LBSC .
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Post by runner42 on Jun 29, 2015 23:11:45 GMT
Oh dear, another I thought innocuous comment that I made for completeness indicating the impact of the code's changes on LBSC's design has brought about another adverse comment on his capability. It was my interpretation of his design that it should be a snug fit, he never mentioned that need in his words and music. I don't understand the comment that the ashpan shouldn't enter into the firebox it is doesn't make any difference whether it sits on, outside or inside the firebox.
I have included a composite picture showing the boiler across wise measurement and the ashpan details, so that you can determine for yourselves the clearance if any between the two. The wrapper material thickness is 13 swg.
Brian
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