Intermediate Level CSBs (and other gizmos...)

[Chris Mitton]

For the unitiated, the ex-GER E4 2-4-0s (Paul Willis would call them T26s) were known to their crews as "Intermediates". (No, I don't know why either!)

Avid readers of this forum will probably have realised that a good proportion of Colin Seymour's last batch of these engines is under construction by Society members, including my own modest effort (it's my first in P4). I've hankered for a model of one for many years - they have a slightly old-fashioned look that seems to go with the bucolic East Anglian lines they frequented. When my uncle drove them regularly up the Stour Valley, and I was in short trousers, I never heard them slagged off (but I did learn some words no nine-year-old should know the day he got a C12!). So retirement gave me both time and finance.....

Anyway, Paul in a rash moment said

As you've started on your E4 build, why not start a thread of your own about it?

so here goes, warts and all, with the first progress report.

First of all, many thanks to Paul, Will, Russ, DaveyTee and others who've answered my questions on other people's threads. I'm still quite confused about the maths of CSBs (but that's for another day), but as Will suggested numbers very close to my own calculations from the CLAG spreadsheet I bit the bullet and started drilling holes (and nearly learnt how to drill such tiny holes without breaking too many of these fragile but expensive tools!).

I've managed now to assemble the frames, which seemed to take forever to get right! I soldered the hornblocks to the frames using the MasterChassis jig, which makes for a very accurate job but doubles as Enormous Heat Sink! However the actual springs (guitar strings) have yet to be threaded through the various holes - I need to extend the front axle carriers first (the suspension will treat it as a 0-6-0 with all the sideplay on the front axle). Today I got as far as discovering some of my theory works, so herewith a couple of photos....

The second photo (for some reason they got posted in reverse order!), of the frames standing on the Isinglass drawing, shows that a Mashima 1220 driving the centre axle will fit into the firebox - not only that, but the rear brake hanger provides a convenient point to rest it on, although I've yet to attach any form of torque restraint. No, I'm not going to bore out the safety valve and put a micro-flywheel in it! Shortening (mostly removing!) the motor shaft is on the to-do list - I recently acquired some diamond-edged needle files from a jeweller's supplier in Birmingham's Jewellery Quarter which successfully managed a similar job on another motor. This layout leaves a bit of room in the ashpan to attach pickups and / or insert some more weight (according to my calculations for the CSBs, the CofG will end up very slightly behind the leading coupled axle, but bringing it a tad further back might be desirable).

The first photo shows that a High Level RoadRunner gearbox will fit between High Level axleboxes without any need for their (imminent) narrow boxes, provided the frames are wide enough - these are 15 mm apart (as near as dammit 16 mm over the frames).

That's it for now - hopefully it will be runnable by the next West Mids AG track night I can make in early April......

Regards
Chris

[dcockling]

For the unitiated, the ex-GER E4 2-4-0s (Paul Willis would call them T26s) were known to their crews as "Intermediates". (No, I don't know why either!)

Hi Chris,

Intermediate = what you would call Mixed Traffic i.e. not purely passenger, not purely freight, but intermediate.

There were a whole family of them: the T19s were the express passenger version, virtually the same locos but with 7' drivers. The C32s (LNER F3) were the tank version, the N31s (LNER J14) the 0-6-0 goods version (ironicaly known as 'swifts') and there were the D27 2-2-2 singles as well.

All the Best
Danny

[Paul Willis]

For the unitiated, the ex-GER E4 2-4-0s (Paul Willis would call them T26s) were known to their crews as "Intermediates". (No, I don't know why either!)

Avid readers of this forum will probably have realised that a good proportion of Colin Seymour's last batch of these engines is under construction by Society members, including my own modest effort (it's my first in P4).

Hi Chris, first of all, thanks for taking the plunge and starting a thread about your E4 build

I also wanted to mention that I'm planning on taking my first kit away to the Missenden modelling weekend in two weeks time. I hope to get a very reasonable run at it there. I must check over that I have all the necessary bits and pieces.

Best wishes with your build, and I look forward to seeing more of it soon.

Flymo

[Chris Mitton]

You look at the last posting and realise that you haven't done anything significant for the last 2/3/4/... weeks and it's time to pick up the soldering iron again!
Cheers
Flymo

errr - guilty as charged! ....except it's a bit more than that since I started this thread, so a progress report is in order....

hopefully it will be runnable by the next West Mids AG track night I can make in early April......

- fortunately I didn't say which April!

E4 number 7492 has actually made quite a lot of progress in the intervening - and really will make this coming April! - so here are a couple of piccies as it was a couple of weeks ago. As mentioned before, it's a Gibson kit, with Mashima motor and High Level gearbox, hornblocks etc.
Photos 1 and 2 show the engine before I did a bit of cleaning up - soldering is not my strong point! It's now nearly ready for painting, except that I haven't yet secured the smokebox front, which will happen shortly when I've weighted it.

StoweFen-E4-1.JPG

StoweFen-E4-2.JPG

I've found empirically what others on this thread have said theoretically, that CSB suspension is very sensitive to the weight distribution. Currently, so far as I can tell - not very accurately, better ideas welcome - the CofG is very close to the leading coupled axle, which is where I want it, but the whole thing is too light. I'll put a roll of lead in the rear boiler ring, which won't move the CofG much if at all, then I think I can just about put a small amount of lead lining the firebox top (above the motor) and a certain amount as inconspicuously as possible lining the cab floor and roof - then a bit more in the front of the boiler to balance those. I also plan to stiffen it up a bit, by replacing the 12 thou guitar string with a 13 thou.
Currently, even without the right weight, the engine runs nicely under finger-propulsion. I haven't yet added pickups - I've made these, a la Morgan Gilbert, and am in the process of improvising a mounting for them which includes the (dummy) leaf springs, which of course had to be sawn off the frames to get the hornblocks in, as one detachable unit. The other tasks left (apart from painting, lettering and varnishing) are buffers, couplings and drawbar, plus a few details such as sandpipes (not that the E4s had many!). The very last task, with some trepidation, will be to Loctite the final drive gear wheel to the axle, preferably without locking up anything else! Then it will be ready for running on Stowe Fen - or would be if Stowe Fen were anywhere near finished!

StoweFen-E4-3.JPG

Photo 3 shows the engine with its tender. When I'd nearly finished the bodywork I thought the boiler looked too high, but on measuring against the Isinglass drawing realised the top is at the right level but the boiler diameter is too small by about a millimetre, due to using a stock size tube. That leaves a certain amount of daylight that is crying out for a representation of Stephenson gear, but that's a stretch too far for my skill level! Nevertheless, I think the model does capture the look of these delightful little engines.

Photos 4 and 5 show the underneath, including the CSB, which is set up essentially as a 0-6-0.

StoweFen-E4-4.JPG

StoweFen-E4-5.JPG

On Photo 5 you can make out the extension piece I soldered to the front carrier to allow for the different wheel diameter - that was fun, making it identical on both sides.... All the side play is on the front - I left some on the rear axle as well, but that meant the crankpins at extreme side displacement occasionally clouted the footplate valance. [That won't be a problem on the J15 I'm now building as the wheels are that much smaller.] Thanks to Keith at Scaleforum for giving me the solution for re-washering without wholesale dismantling! It now goes through my B6 test plank easily, which is all I ask of it.

Finally, photo 6 shows its tender, which isn't really that closely coupled! In fact it doesn't have a drawbar yet, nor buffers or couplings, (nor coal!), but otherwise it's ready to roll.

StoweFen-E4-6.JPG

This picture gives a clue to the inordinately long gestation period of my first P4 loco - it also has a train! That will appear soon on the Coaches thread.....

Hoping that 2013 produces more progress that 2012 managed,
Regards
Chris

[Will L]

To add to the balanced weight, you could do worse than learn from my mistakes, see this post. A fair bit of extra weight can be added in clear view, in the form or white metal loco crew! Placed as far back in the cab as you can manage they will nicely balance a big chunk of lead up front.

Will

[nigelcliffe]

Interesting thread as an E4 is on my "one day" list (I am on the list for when Gibson do another run).

For weight, in photo 4, it shows a lot of space under the loco, behind and around the gearbox (firebox area) and around the rear axle (below cab floor). And what appears to be a large space behind the motor (rear of firebox inside loco body). My 2mm loco building experience tells me that weight low down is better than higher up.

- Nigel

[Chris Mitton]

Thanks for the advice, gents....
Will - I hadn't thought of a crew, but now you mention it whitemetal is mostly lead (isn't it? I stand to be corrected) so that's a good idea. Possibly even supplement the driver and fireman with a representation of my ten-year-old self and maybe a couple of mates, with satchel and sooty morning faces, freeloading like slightly fast snail unwillingly to school (apologies to your namesake Mr Shakespeare).
Nigel - likewise thanks. Now you mention it I can get more than I thought around the cab, although the firebox space isn't quite as big as the picture suggests there is some room. Presently the loco weighs around 140 grams, my aim is to get it up to about 180, which is what the spreadsheet suggests for a 13 thou spring. The loco at present appears to be reasonably well balanced (more than can be said for the prototype, which was front-heavy!), and there is plenty of room in the front part of the boiler, so the strategy will be to stuff as much as I can in and around the cab and rear frames, then put enough in the front part of the boiler to bring it back into balance.

Regards
Chris

[billbedford]

Thanks for the advice, gents....
Will - I hadn't thought of a crew, but now you mention it whitemetal is mostly lead (isn't it? I stand to be corrected) so that's a good idea.

Used to be, it now mostly lead free.