Member postings for bogus

Paul, this is now clear. Much appreciated

At this point i think that any addition/modification to the boiler that require silver soldering, meaning high temperature treatment - is a real problem. I've read about "chasing the leaks" after subsequent silver soldering (in case of repairs or mods). So if any bushings are to be added it impose a problem. I can't see the place for regulator valve as well. Apparently, as i said earlier, there were two designs: main one is the smokebox mounted regulator valve block, and alternative design: internal regulator with the bushing and glad on the back head. I found this info here:

http://www.itech.net.au/modelengineer/me_response.php

Boiler construction started in volume 107:

"Smokebox Regulator. Superheater, distance-piece, regulator block, details of regulator, poppet valves, regulator shaft, bottom cover, how to assemble the regulator, erection "

And later:

" Alternative Regulator of the Slide-Valve Type. Distance pieces, regulator body and valve, operating gear, how to assemble and erect, regulator rod and backhead gland "

Is the thing at the bottom left of the photo below a part of the regulator of the first type (smokebox mounted)?

The steel shaft looks like "regulator shaft" however the rest is mystery for me... It just doesn't much with the arrangemens i've seen on the internet.

Anyone have these ME volumes 107 and 108 for reference?

Dear Engineers,

by scrollin through the web i've found partly build Britannia locomotive, 3.5" gauge, that was described in Model Engineer magazine. I believe in volumes 104 to 109. I've seen a few different builds of 3.5" Britannia locos and couple of things catched my attention: the boiler, regulator valve, superheater. The one i'm talkig about is here:

And it doesn't have holes on the top for the water feed valve like in this example the holes are marked 1 & 2 below:

And it doesn't have the element protruding from the boiler (RH side) - number 3 above. This element looks like a support/pivot for the linkage of the steam regulator valve located in the "cube" in front of the smokebox - number 4. Not mentioning about superheater (for sets of superheating pipes).

However in the loco in question (first two photos) the boiler is different, not many bushings for valves, etc. in the cabin. And boiler back head arrangement:

I found another example of Britannia in 3.5" gauge and here:

In the above example the superheater is simpler and there is no regulator valve in the smokebox. Boiler arrangement in the cabin is even more different. I'm confused. Were there different options described in Model Engineer magazine?

Another question: the offered boiler is naked: no fire door mounting holes, no regulator handle support holes and as per description it was proffesionally made, tested and have all the papers (though outdated). Does it mean it has to be drilled to mount all the necessary stuff? What about the certificate then? Is it normal practice that the boiler ws tested, certified and the some new holes are made? Much confused:/

Please share you thoughs on that. Is it worth to thing about that project?

Wojtek

Julian, you're totally right. I won't

Now i fully understand this part. Thank you. Double happy as i got message from my wife about delivery - i was lucky to find 5mm O.D. borosilicate glass capilary tubes, 0.8mm wall thickness so the capilary action false readings will be minimised. Rated for 26 bar of pressure. I broke water gauge accidentially during disassembly. What a day

Wojtek

Thank you so much guys for your advices. It looks it will be an awkard job.

If i remember right the play is mainly (if not only) on the linkage that is connected to the valve slider block (light blue color in the photo). It looks like the holes the red screws are going through are worn. Julian if i understand you correctly - should i assume that if i undo the gland (bard blue) and flange (violet color) and slide the rod assy. out of the boiler the square section on the end of the rod will just slide out of the green element? Good point to suspend the slider first! Any way if i have to make light blue element i will still need to undo the red screws so i guess - remove the valve from the boiler. The thread numbered "2" should have more gripping force than the one marked "1" so "1" should give up first though there might be surprices (like glue). I'm not very into the imperial threads: thread marked "1" says 5/16" - but what pitch? All three marked "1", "2", "3" should have tha same pitch.

Thanks!

Wojtek

This is the one i have! I reconize it THANK YOU John Very smart arrangement. I guess i'll have to use HEAT during the job. These threads probably haven't beed touched since ages. And i bet someone used glue (or different type of sealing agent) to seal the things.

Any one can share some drawing of this arrangement please? Of course i can not be 100% that the builder of my loco have done it as per drawings. Howeve i studied many photos of other 3.5" gauge Maisies on the web and most of them have regulator arrangement in the cabin looking like on mine. Haven't seen regulator valve under the steam dome, though. Any one have photos of it? I couldn't find them on internet.

Thank you guys.

On mine there is only one screw - i suppouse this is the one (steel, round head, slotted):

I tried to move it but at some point of force i decided not to go any further. Maybe i'll try to heat it up. Maybe the builder used some kind of blue to seal it. However i don't understand how the rest of the assembly. Even if i remove the srew holding the valve body in place what about the other two elements:

1. the stem/bar(?) going to the handle in the cabin - here i assume it's only going via some kind of sealing. But here again: i tried to undo the threaded elements and give up at some point

2. the arrangement going from the valve to the smokebox. It is mystery for me... I thiught it should be rigid. I can't see any means to undo at the smokebox side:

The reason is two fold - i'm VERY curious and there is a backlash in the connecting linkage elements of the regulator valve. I can do ca. 15 deg of movement on the handle before the valve sliding plate starts to move in the opposite direction. For me it's way to much in terms of "response".

i bought it from Ebay auction, from one guy who is most likely well known in this "world". I supouse he is well known as he is selling lot of locos all the time on Ebay - squireathuttonbs24

He said is it very vell engineered and wasn't been on steam since long time, was standing on the display and need "all the necessary work"

I haven't seen any stamps on the boiler...

If i remember right, there is a red dot marked on the pressure gauge at 70 psi.

Well the answer is i'm offshore for the next 2-3 months. All i can do now being far away from home(workshop) is to collect knowledge, materials and talk In my other thread regarding steam regulator disassembly i was advised to get the book. Nice It is on the list, but in 3 months and i need to prepare tooling first not to waste time when i get home.

There is no risk to public.

Back to the boiler: it is all silver soldered. Stays are also silver soldered. The photos are taken before i finished cleaning.

Edited By bogus on 30/05/2020 18:30:13

I plan to steam it on the test bench only. in the future i plan to make a track in my future garden - not big, maybe 1500 square meters plot. I think it should be enough tor 3.5 gauge. Only private use.

it's on my list

Hi,

i'm struggling trying to figure out how regulator valve assembly is made and how to take it apart. I'ts kind of slide gate valve as i can see in the steam dome. But i do not know how to diassemble it. There is some backlash in the linkage which connects long stainless steel rod going from the handle in the cabin with sliding element that open steam channel. Pls, see the photos - regulator closed:

Regulator opened:

It looks clean as it is after soda blasting. However i'd love to have better response on regulator by eliminating the play in the linking elements.

From the smokebox it looks like this:

I'm affraid steam outlet is fixed to the boiler body for good:/ These three small threaded holes are for superheater assembly:

And this is how it looks like from the cabin side:

Unfortunatelly i have no book and it is hard to guess. I don't want to use too much force.

Can anyone chack in the book what is the design arrangment? The basic question: is the regulator designed to be repairable? 

Edited By bogus on 29/05/2020 21:25:36

The problem is there is no live steam models boilers inspectors around me. ZERO. In Poland there is no live steamers clubs or associations. No market for that. We had different problems in the past...

Now i'm collecting necessary taps and dies to make plugs and new fittings. Some of them broke when trying to undo threads! What i dont like is the way hand rail going along the barrel are fitted to the boiler. These are screwed into the boiler body directly! I bet someone used glue for that as all of them need to be lined-up accurately to pass the rail bar through the holes. Unfortunatelly some of them are broken. How to fix it? I plan to drill and cut new thread in the boiler shell (the shell is 3mm thick i think) and screw in plugs using Locktite (high temperature). These plugs will have blind threaded holes for new handrail fittings - this way there will be no problem with leaking handrails fittings. You can see these small threaded holed here:

And some broken fitting - boiler water feed check valve:

BIG QUESTION: how to remove scaling from the inside of the boiler? It is not bad, but i'd like to descale it / remove "limestone". I know the broken feed valve is showing a lot of scale but i've check inside with boroscope and looks good. I have a problem with regulator but i need to start new thread as it is quite different story.

Edited By bogus on 29/05/2020 21:04:18

Guys,

by telling "it was soflt soldered" i was reffering to the WRAPPING only not the boiler itself Boiler is silver soldered for 100%.

Here's the boiler AFTER i removed the wrapping brass sheets. The below photo was taken during the cleaning. You can see, at the lower right corner of the firebox crown fundation (is it good naming?) - it is soft solder. It looks like someone was repairing that? On the forum i heard that was/is the normal practise. Is it?

Here is the boiler after i cleaned it:

For cleaning i used soda blasting technique - never heard someone using it for boiler cleaning but it is completely harmless for boiler elements and solders. I had weak compressor available and the cheapest "sandblasting kit" so it took a while to clean it and the cleaning process for sure can be stronger when using better gear, however i'm pretty happy with the result. What you think? The good thing about soda is it is not aggresive, user friendly (eventually you can brush your teeth or bake a cake with it) and after cleaning just put boiler in water to dissolve any soda leftovers.

Another view - preparation for cleaning:

Inside of the firebox - do you thing these whiteish thing on the stays are the signs of leak?

Smokebox side after cleaning:

Thank you for explaination guys. If i manage to find 1mm thick insulation material i think i'll try to use it as i need to make new wrapping anyway. Smokebox is ordinary mild steel. Maybe i'll make slightly bigger one to accomodate O.D. increase of the boiler?

Edited By bogus on 29/05/2020 13:19:26

Dear Fellows,

in order to take the boiler for cleaning and inspection i hade to take all the wrapping off the boiler shell. It turned out it was soft soldered (grrr!), including the bands "holding" wrapping brass sheets sections. To desolder them i had to head them up to the temperature at which paint came off... Not only that: firebox section was badly bent and damaged during this job.

This is my first loco and i don't have experience with sheet metal work. Could you advice me how to make a new wrapping? rounded sections are fairly easy - i'll make cardboard patterns to make all the necessary holes (for water check valves, chminey, steam dome, etc.) however the firebox section is a nightmare.

Another thing is i found the builder didn't "lined" the boiler. I don't know if it is a good word for that? I'm reffering to that thin insulation layer wrapped around the boiler shell, under the final metal sheet wrapping. I know it is to reduce energy losses and i'd like to use it when making new wrapping. However that insulation has thickness... Could you point me to the source where i can see what material is usuallt used for that? And what thickness should i use. What worries me is the fact that smokebox O.D. is now equal with original wrapping (brass sheet ca 0.5mm thick). If i add, say 1.0mm thick layer it will increase overall O.D. of the boiler by 2.0mm and it will not be equal to the smokebox O.D. anymore.
What you think about that?

you convinced me - even if plan to fire my engine twice a year i'll use proper materials. I'll go to local foundry. They are doing things out of alu, brass and bronze - mainly B101 (CuSn10P). I'll ask to make some B101 stock for my small lathe.

John, regarding the Maisie - have you got some instuction manuals, characteristics/technical data of the model, drawings? Actually i need every kind of information. This is my first time i have my hands on coal fired steam engine. Already did some mistakes during stipping the loco and i'd love to avoid more mistakes:/

I uploaded the latest photos i took last days showing current state of the boiler. Comments much appreciated.

Wojtek

Maybe i confused you. By telling about 7/16 was reffering to safety valve on different loco i have. Different diameter, the same pitch 26 tpi.

Wow, thank you Paul. Never heard of brass and cycle threads...

My thread leaf gage is Whitworth 55 deg. and when checking the thread pointing it to the light i can see uniform distances between gauge thread form and safety valve thread form along the thread tooth. This suggest it is 55 deg. However, with such a small pitch, it is really hard to tell the difference:/

Ihave Royal Scot from LBSC drawings - safety valve thread is denoted 3/8" - 26tpi. No info weather 55 or 60 deg.

Do you think these should be ok?

https://www.tracytools.com/taps-and-dies/whitform-taps-dies?product_id=1091

https://www.tracytools.com/taps-and-dies/whitform-taps-dies?product_id=1098

thank you,

Wojtek

ok. So far i've identified the threads around the boiler, well most of them. Turned out they are Model Engineering threads - ME1/4-40, ME1/4-32, ME9/32-40, ME7/32-40, ME5/16-40 - now i'll collect taps&dies to make a plugs, repair/make fittings, etc.

Got problem to identify safety valve thread - O.D. is 12.5mm - apparently 1/2 inch however the pitch is 25 or 26 tpi... I can risk 26 tpi is the true. Hard to say as there is only 5 turns. Anyway, i can't find the thread 1/2 in in diameter with 25 or 26 tpi. UNEF is the closest one but mine is not 28 tpi for sure. Funny, as on the second loco safety valve have 11.0 mm in diameter so it look like 7/16 and the same pitch - 26 tpi. Confused:/

As to the boiler - as you guys suggest - if it turn out not leaking i'll not touch it...

Maise LBSC - thank you Paul, yes, i know it. Already tried to find as many info as possible. Unfortunately not much on the internet.

Wojtek