Overhaul of a 9F

[don9f]

Thank you both for your replies and I now have all the info I need to add these “ashpan cleaning doors”. I can well understand that when the early engines didn’t have them, it would have been very difficult to clear the upper parts of the ashpan, as the slope is very shallow. The info supplied thanks to Adam shows the drawing of the ashpan was amended in August 1955 to include the doors. This would have been around the time of completing the first 50 or so engines at Crewe, so anyone modelling an early built 9F could legitimately leave these complicated little extra fabrications off what is already a complicated ashpan to make!

Cheers Don

[92220]

Hi Don.

Adam's drawing refers to the BR drawing SL.BR/1439 Ashpan Cleaning Doors. I found it among my drawings. Will get details to you.

Bob.

[don9f]

Hi Bob, since writing that last post, I’ve edited it and added a photo of 92220 that shows the doors in question.

Cheers Don

[92220]

Hi Don.

I found a close-up photo of the door. I'll get it into Imgur and post it. Evening Star's doors look as if they may have been repaired/modified as they don't quite match the drawing which has the top and bottom lifting levers hinged, but Evening Star's are just bits of round bar welded in place.

Bob.

[92220]

Hi Don.

Here is the photo I found:-

This photo is better than the one I first found. It shows that the upper catch is actually a sliding bolt. The bit of bar at the centre on the bottom acts as a catch to keep the door horizontal when open.

I had thought the door had been modified/repaired. When I had a better look at the drawing, the door IS to drawing but it needs careful reading as the dimension lines confuse the eye because they are over the drawing. As a draughtsman, I was always taught that dimensions should always be outside the component outline wherever possible, to prevent that confusion! Oh, and the drawing is in First Angle projection.   

Bob.

[don9f]

Hi Bob, that’s a great photo and shows just how close the front ash door assembly is to the wheel and it’s flange....the area behind the door as we look at the photo is actually relieved to give clearance over the wheel, which makes the fabrication all the more complicated.

I would suggest that Evening Star’s doors have been modified as that bit of bar welded at the bottom centre is not as its supposed to be, the normal arrangement for each door being two rather pointed “stops” sticking out, that the door rests on when open. It could be a Museum mod, to eliminate things that stick out, perceived as a hazard to anyone bending down / young people etc?

I’ve made a start on the additions to mine....update with photos in due course.

Cheers Don

[Cro]

Don,

Out of interest, how have you fixed your ash pan to the boiler? It's one thing I haven't solved yet and have a few options I'm debating, one being blind studs in the foundation ring......

Please show lots of details of the parts as it is still an addition I need to do.

Adam

[don9f]

lWill do Adam....mine has always been attached to the foundation ring by 8 x 5BA stainless studs & nuts. It’s similar to the full size, although as you can see in that photo of Bob’s, the attachment is via pegs & cotters, with spacer washers as appropriate. I expect this was a quick and easy way for Works staff to fit the ash pan, as the boiler would have to be supported by a crane at the time, prior to lowering it into the frames.

As you can see in the photo above, mine is made from stainless steel, partly riveted and silver soldered together, but I had to reinforce some joints after the first few steamings, due to bits of it coming apart! In one of its last outings back in 1996, the front plate fell off altogether and has now been replaced, held in place by more brass angles....fitted on the outside to leave the inside of the hoppers as “clean” as possible.

The design included a removable pin arrangement that allows the central grate section to pivot forwards & down and then be removable via the front hopper door....same for the side sections once slid over, but in practice I’ve never used that feature....it’s much too fiddly. All 3 grate sections can be removed using a set of forceps, through the fire hole doors.

The drawing of the real real thing shows just what a complex fabrication the whole thing is!

Cheers   Don

[don9f]

Hi, as I mentioned in a previous post, the early built 9Fs did not have the "Ashpan Cleaning Doors" as they are known, until somewhat later. The photo below shows a new ashpan and grate (with some finger bars still to be fitted), without these doors, ready to be fitted to a new boiler. Note for interest how the grate is entirely supported by this fabrication....there is no support provided at all by the boiler / firebox itself.



I decided I was going to make and fit some dummy doors to my 9F and started by cutting and folding some thin card with much trial & error, to get to the stage where I could make two metal templates for subsequent marking out the thin stainless sheet for the four doors. The front pair are slightly bigger than the rear pair and also include an awkward curved "pocket", because the trailing edges of the front assemblies have to clear the tread / flange of the trailing driving wheels, which are very close. Allowance obviously has to be made for maximum deflection of the suspension, plus the rearward expansion of the boiler when in steam.



I spent a whole day making and folding three of these little fabrications from some .018 inch stainless sheet, silver soldering them together etc, before deciding they weren't good enough, so I scrapped them and started again, this time using some thicker 0.7mm material which produced a much better result! I had to keep fitting them to the ashpan with temporary screws, fitting it to the foundation ring and then lifting it into position on the frames, to make sure things lined up ok and didn't foul anything. The whole thing is a tight fit, particularly along the top edge of the frames and the shape and positioning of these door fabrications is quite critical.






The next photo (upside down) shows the lower edge of the door has been notched as per the full size....the "tabs" protecting the hinges somewhat.




Then came the time for some fiddly detail. As mentioned, my doors are only dummies, but I wanted to try and make them look a bit more like the real things, so had to make up something to mimic the bolting arrangement, plus the hinges at the bottom. These parts were a mixture of steel and brass and following the silver soldering of one little boss towards the top of each door, the rest were soft soldered into place having cleaned the stainless and using Bakers Fluid as a flux. I'd read various theories about soft soldering stainless steel, but it went ok, although you do have to clean it, then clean it again and the Bakers worked fine.











Next time I hope to show it all fitted to the frames.

Cheers   Don

[92220]

Hi Don.

That cleaning door looks great. The ashpan looks good too. Very handy pics which I've copied for future reference!!

Bob.

[don9f]

Hi Bob, glad you liked them....I forgot to say it’s thanks to yourself & Adam that I had all the details of the full size to work from.

Will you be making yours functional?

Cheers Don

[don9f]

Hi, since the last post on the subject of the ash pan, I have started refurbishing the main steam pipe / superheater header / elements / connections to cylinders etc. The original elements seem to be in excellent condition so will be reused, but the main steam pipe ( from the regulator valve), some parts of the wet header and all pipework to the actual inlets on the cylinders will be renewed. Some of this lot was dismantled years ago and had to be sawn in places to get it all apart.

Originally copper extension pipes were silver soldered (with bronze sleeves) onto the straight lengths of the elements....both wet and dry sides....but in service, the copper pipes on the dry side suffered badly in the smokebox environment and were replaced fairly early on with thicker walled pipe to prolong their life a bit. There was discussion some time ago about this problem somewhere on this forum and I may experiment with brass pipes this time round.

Haven’t had much time in the workshop for a few days so will take photos of this current part of the project soon, but in the meantime here are a couple of the new ashpan “doors”. The photos are not too good as I haven’t got any decent lighting and my Ipad doesn’t have flash....will have to charge up the big camera! Please forgive all the crud on the wheels....haven’t really cleaned these up yet.

Cheers   Don

[don9f]

The superheater elements in the Warnett design 9F boiler are shown as 9/32" dia stainless for the straight lengths, with 9/32" copper extensions joined on for the various bends and connections to the wet header/steam pipes to cylinders etc. I used 7mm stainless as this was easy to obtain and is only a few thou smaller.

As a bit of an experiment, I decided to shorten the elements slightly as I always felt that they were very efficient and maybe didn't need to be so quite that much. I am going to eliminate the copper additions to the wet side of the elements and connect the stainless sections directly to the wet header. This meant that these four lengths of stainless needed a 60 degree bend adding so they could rise up out of the flues, to meet the header. Some years ago I made a pipe bender for just such a job on a Martin Evans "Jinty", but this had 1/4" elements....so I obtained a 7mm ball nosed slot drill and modified the relevant parts of the bender to suit. You can see in the photos that the cutter was used to create exactly semi-circular grooves in the former, clamp and follower.



I cut off all the remaining stubs of the old copper extensions and cleaned the ends of the stainless sections, but before actually bending them, wanted to do a few trial bends on the same brass tube I'm going to use for the new "dry" extensions this time. This is 7mm brass tube, which I found had a diameter of 0.277 on my micrometer, or just over +.001" and I found that as the ball nose cutter had cut exactly to size, my "7mm" brass tube didn't quite fit! A bit of a rub with some emery strip soon sorted that though. I had "knocked up" an assembly jig, with dimensions closely mimicking the positions of the header, flues and steam outlets from the smokebox, but forgot to take a photo today....will have one for next time.



After a bit of trial & error with the brass, got the bend positioned in the right place and bent the ends of the stainless to around 60 degrees, as this is the angle of entry of the original wet extensions into the header (which has been rebuilt).


















Tomorrow I hope to finish making up the brass "dry" extensions to the outlet fittings and photo the whole assembly in its building jig.

Cheers Don

[92220]

Jan 22, 2018 22:27:56 GMT don9f said:

Hi, since the last post on the subject of the ash pan, I have started refurbishing the main steam pipe / superheater header / elements / connections to cylinders etc. The original elements seem to be in excellent condition so will be reused, but the main steam pipe ( from the regulator valve), some parts of the wet header and all pipework to the actual inlets on the cylinders will be renewed. Some of this lot was dismantled years ago and had to be sawn in places to get it all apart.

Originally copper extension pipes were silver soldered (with bronze sleeves) onto the straight lengths of the elements....both wet and dry sides....but in service, the copper pipes on the dry side suffered badly in the smokebox environment and were replaced fairly early on with thicker walled pipe to prolong their life a bit. There was discussion some time ago about this problem somewhere on this forum and I may experiment with brass pipes this time round.

Haven’t had much time in the workshop for a few days so will take photos of this current part of the project soon, but in the meantime here are a couple of the new ashpan “doors”. The photos are not too good as I haven’t got any decent lighting and my Ipad doesn’t have flash....will have to charge up the big camera! Please forgive all the crud on the wheels....haven’t really cleaned these up yet.

Cheers   Don

Really nice job on those doors Don. They look so real! Keep the post coming. They make very helpful reading.

Bob.

[don9f]

Hi Bob, thanks for your comments....I did think about trying to deeply scribe the actual door outline (they are rectangular) onto my little fabrications but decided against it because of the risk of it going wrong. A fellow member in our society has made the ones on his 9F really open....but they don’t actually give access to the inside of the ashpan! I’m afraid that would all be a step too far for me.

I spent today on more pipe bending etc. and the photos show where I’ve got to.

First two show the stainless elements and their extensions positioned in the assembly jig:-





First parts to be silver soldered were the “dry” extension joints at the outlets to the cylinders, naturally being careful not to set the jig on fire!



Then having carefully marked each one of the “wet” bends where they entered the header, removed them from the jig and reassembled them upside down for better access. Carrying out this step out of the jig was essential....as otherwise it would definitely have been on fire! Photo was taken after cleaning up obviously.



That’s it now for a few days, hope to join the extensions to the stainless elements next time and then have a trial fit in the boiler with smokebox also in position.

Cheers Don

[simplyloco]

You've just given me a very good idea!
John

[don9f]

Do tell!

Don

[Cro]

Lovely Work Don, Like Bob I have this to do one mine as the ones supplied with the Kit only just made it into the firebox, I found it would start wet but after a little running it would start to dry up a bit but I would rather it better so I now have some stainless tube to weld up for spear heads. I only have 2 flues in the boiler but going to see if I can get 4 elements in and this shows a neat solution for putting it all together. Love the jig too!

Adam

[don9f]

Hi Adam, yes 4 “passes” through each flue is also typical of full size, certainly the 9F, which had 35 such flues.

My elements have become about 65mm shorter than they were (originally reaching right to the rear of the firebox), but hopefully this will be ok. I only use max. 80psi and never had problems with “wet” steam, even when pressure dropped right down.

I will keep the jig in case I ever need to remake these again....the one I built when making them first time has long since disappeared!

Regards Don

[Cro]

I need to crack on with the cladding first. Which lets me get cab in place so I can then make regulator and the linkage to then do superheaters! I have it all worked out in my head.....!

I never really got a chance to test her fully before as regulator wasn't big enough to allow enough through. A half decent load was enough for it and it would only plod along really, not enough for a big engine!

Adam