SCC - Sparkshot Custom Creations

[Knuckles]

Whisky armchair modelling/drawing, sounds like a job for you!

Sounds pretty good to me, maybe one too many were supped in the process though.
Ok many thanks for your input also. Jol made some good points on RMweb too ( and previous page) but I'm waiting to see if there are any more yet before I reply.

Current thinking is to carry on as I am but design the leading wheels to take both sizes depending how it is set up. This way you could run the loco with both wheel sizes providing you don't mind the smaller wheels dropping the whole engine by 0.75mm or so. (Rough guess not calculated yet.)

I also am thinking of the different methods of getting the leading wheels to turn. One idea is a simple Pony set up sliding through non existent hornblocks (thus already cut out if you want to add real ones) but if I did that the wheels would twist whereas the diagrams I have been looking at have a more lateral slide effect so a simple joint may provide that but if in the wrong place it will turn wrong. Will come to this later though as it is a while a way before it matters, just getting the wheel issues cracked first.

Also from a different thread...

Allan's latest post on his building thread about filling the gap between side tanks and the boiler was also discussed recently on the forum of the Brighton Circle - the group for those interested in the LBSCR. Looking at a range of pictures it appears that Brighton practice was to fill in the gap all the way along with what looks like a continuation of the top of the tank, rather than a separate piece of metal. On some of the larger tank locos, such as the I class variants which had a sharp top edge it looks like the top on the tank is set down by an inch or so. This area was often used for storing fire irons and spare loco lamps and some locos were fitted with lamp brackets for that purpose. The fact that in some instance the bottom of the lamp cannot be seen suggests that the tank top is lower then the top of the sides. The smaller classers had a rounded top edge so this would not have been possible for those types but some of those also had lamp irons fitted - a nice detail to model.

It does however illustrate the need to get as many pictures of the loco you are building as possible and as Allan says, the standard side on and 3/4 views often don't show all that you need.

Terry Bendall

Relevant to the J1 also!


For everyone who may be reading this there is some new stuff on the previous page.

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[Will L]

I also am thinking of the different methods of getting the leading wheels to turn. One idea is a simple Pony set up sliding through non existent hornblocks (thus already cut out if you want to add real ones) but if I did that the wheels would twist whereas the diagrams I have been looking at have a more lateral slide effect so a simple joint may provide that but if in the wrong place it will turn wrong. Will come to this later though as it is a while a way before it matters, just getting the wheel issues cracked first.

The prototype seems to have had radial axles like most but not all 2-4-2s. London Road Models use to do an etch for two radial axles which might help you, but I cant find it on the current web site.

[Knuckles]

I also am thinking of the different methods of getting the leading wheels to turn. One idea is a simple Pony set up sliding through non existent hornblocks (thus already cut out if you want to add real ones) but if I did that the wheels would twist whereas the diagrams I have been looking at have a more lateral slide effect so a simple joint may provide that but if in the wrong place it will turn wrong. Will come to this later though as it is a while a way before it matters, just getting the wheel issues cracked first.

The prototype seems to have had radial axles like most but not all 2-4-2s. London Road Models use to do an etch for two radial axles which might help you, but I cant find it on the current web site.

Thanks. Much appreciated.

This is what has currently been going through my mind...

[Armchair Modeller]

Whisky armchair modelling/drawing, sounds like a job for you!

I wasn't suggesting that people were deliberately trying to mislead modellers, by the way. Expectations were lower in the good old days and I suspect some draughtsmen got a bit carried away with enthusiasm.

[billbedford]

I also am thinking of the different methods of getting the leading wheels to turn. One idea is a simple Pony set up sliding through non existent hornblocks (thus already cut out if you want to add real ones)

The original almost certainly were fixed in the frames. There just isn't any roof for gadgets inside of the hornguides. And for a loco of this size there is no need for moving the axle. Much bigger 0-6-0s work perfectly well.

[Knuckles]

Fair point, Bill. I'm just thinking of 00-ers who may want to wrap it around a 1st radius curve or something. The more versatile or adaptable with minimum fuss the better. I'd rather the leading wheels be able to traverse more possibilities if possible.

I have envisioned with no more than mental simulation putting sprung hornblocks in with the pony or radial arrangement but with enlarged holes cut in the hornblock brass to allow for some swing.

[Jol Wilkinson]

The prototype seems to have had radial axles like most but not all 2-4-2s. London Road Models use to do an etch for two radial axles which might help you, but I cant find it on the current web site.

Will,

the Radial Truck etch is found at the bottom of the LNWR locos section http://traders.scalefour.org/LondonRoad ... ssis/lnwr/

code LNWRT. One packet contains an etch to make one radial truck, with bearings and guides.

Jol

[billbedford]

Aye, this is the drawing I'm taking most cues from as it matches the photographs loads better overall. The scale rule on the drawing gives a driving wheel wheelbase of 8' so the model currently has that. Other sources of 7' 9" and 8' 6" are making me seriously wonder what is going on and part of my reasons asking for help on all this. To someone researching something already searched (research in a nutshell) anomalies and contradictory information causes much problems knowing what to believe initially.

You have to be certain that all the locos were built at the same time and to the same drawings. I was common in the 19th century later batches of loco to subtly increase in the size of certain dimension, even though they looked the same.

I suggest that since you know the the wheel sizes and wheelbase from other sources, you draw the wheels as an overlay to the Pochin drawing and get the 'best fit' for the driver inside the splashes. This will still leave you with a major problem, in that it is obvious that the wheels just fitted into splasher whose overall length was roughly the same as the tank/cab side plate, however the ends of the splashers would have been 1/4" steel and you have to draw the model with a 0.7 mm minimum wall, so the wheels are almost certainly going to foul the over thick splasher end. This will be even more true if you expect the models to be built with wheels with overscale flanges.

Also vertically between the front of the tanks and the boiler cladding. Since firemen commonly climbed on top of the tanks to fill them, there were also safety reasons for the later practice.

Noel

Again many thanks, this helps too.

On section 3 issue then would you say this pic is roughly how it would look? I say roughly as it is still early with no detail whatsoever.

Sort of, if you look at the head on view of the FR loco you can see the shape and position of the forward splasher marked by the rivet detail on the tank front. I'm certain the extension of this plate was square at the top, i.e. the plate was 'L' shaped.

[billbedford]

The prototype seems to have had radial axles like most but not all 2-4-2s. London Road Models use to do an etch for two radial axles which might help you, but I cant find it on the current web site.

But these locos were built as 2-4-0s and so they would almost certainly not have had radial trucks on the leading axle. They may have had radials axleboxes on the following wheels after they were rebuilt to tank engines.

[Knuckles]

AYou have to be certain that all the locos were built at the same time and to the same drawings. I was common in the 19th century later batches of loco to subtly increase in the size of certain dimension, even though they looked the same.

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BI suggest that since you know the the wheel sizes and wheelbase from other sources, you draw the wheels as an overlay to the Pochin drawing and get the 'best fit' for the driver inside the splashes. This will still leave you with a major problem, in that it is obvious that the wheels just fitted into splasher whose overall length was roughly the same as the tank/cab side plate, however the ends of the splashers would have been 1/4" steel and you have to draw the model with a 0.7 mm minimum wall, so the wheels are almost certainly going to foul the over thick splasher end. This will be even more true if you expect the models to be built with wheels with overscale flanges.

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CSort of, if you look at the head on view of the FR loco you can see the shape and position of the forward splasher marked by the rivet detail on the tank front. I'm certain the extension of this plate was square at the top, i.e. the plate was 'L' shaped.

A) Certainly seeming that way!
b) Your suggestion is what I currently have done, and your point about the 0.7mm minimum wall thickness and all that is also part of the issue - couldn't agree more. I have one photograph showing what I believe is the box splasher protruding a little past the front cab opening where you would climb up and so it is modelled too. Doesn't look too bad but could be better. If the wheelbase was 7' 9" it would help a lot but currently it is set to 8'.

C) I think so too, seems clear enough. It's just the top bit is awkward as I haven't any drawings or photographs showing it in any clear way. What you and a few others said about the cladding meshing with the boiler becoming a later standard to stop broken ankles and such like seems the logical solution so will go with it for now.

Thanks for your help.

To Jol, I know you suggested getting the etch but I have a drawing of a radial arrangement that is is ok to use at the moment, but thanks for the suggestion. I can always change my mind.



Pic shows an Adams radial arrangement quite clearly showing how the design is built for lateral and arcing motion best I can tell. The frames may foul things if the wheels turn too much, again thinking mainly of tight radius 00 curves but some frame overlay thickeners would be easy to provide as an option starting with things thinner and more towards the centre. Still mulling.

BTW Jol, just a random compliment from nowhere. I've seen your London Road layout in person once and on video's a few times and am thoroughly enjoying it. How you paint those coaches though.

[billbedford]

Pic shows an Adams radial arrangement quite clearly showing how the design is built for lateral and arcing motion best I can tell. The frames may foul things if the wheels turn too much, again thinking mainly of tight radius 00 curves but some frame overlay thickeners would be easy to provide as an option starting with things thinner and more towards the centre.

Yes but that loco has outside cylinders and the carrying wheels are in front of the cylinders. The FR loco has inside cylinders with the carrying wheels close behind them. This drawing shows the arrangement on a LNWR 5'6" 2-4-2T which has similar overall proportions to your loco.

LNWR 5ft 6in 2-4-2T cylinder.png

Of course if you want to make things more complicated than they need to be......

[Knuckles]

Thanks, Bill.

I'm not copying the drawing, was just taking the general concept from it. Thanks for posting yours too.

I'm not trying to make things more complex than they need to be, rather I'm not yet convinced having the leading wheels as a fixed axle is the way to go here. I also have a 00 test track and if something won't go around a 2nd radius curve as built with no modification I put it in the instructions as a note.

[Jol Wilkinson]

The LNWR drawing doesn't look like a radial truck. I don't have access to my library at present and so wonder if the 5' 6" tank only had a radial at the back.

On the 4'6" Tank I had to taper in the frames at both ends to get it down to 24" radius curves.

[Knuckles]

On the 4'6" Tank I had to taper in the frames at both ends to get it down to 24" radius curves.

I'm glad you said that as it gives some possible credence to my previously mentioned thoughts and solutions.

The frames may foul things if the wheels turn too much, again thinking mainly of tight radius 00 curves but some frame overlay thickeners would be easy to provide as an option starting with things thinner and more towards the centre. Still mulling.

[dal-t]

The LNWR drawing doesn't look like a radial truck. I don't have access to my library at present and so wonder if the 5' 6" tank only had a radial at the back.

On the 4'6" Tank I had to taper in the frames at both ends to get it down to 24" radius curves.

The drawings in Talbot's "Illustrated History of LNWR Engines" do suggest the 5'6" tanks only had the radial box at the rear. The 4'6", on the other hand, seem to have had radial axles front and back. The LRM chassis kit for the 4'6" tank doesn't include the radial truck etch (unless I've lost it, along with the instructions - will have to order another (or two?) anyway). Fixed at one end does beg the question of how differently the tanks road bunker-first or chimmney-first, however I do recall that one of the reasons given for 2-4-0 designs lasting so long as passenger traction was that the (fixed) carrying wheels led smoothly into curves.

[Jol Wilkinson]

The LRM chassis kit for the 4'6" tank doesn't include the radial truck etch (unless I've lost it, along with the instructions - will have to order another (or two?) anyway).

David,

the LRM LNWR 4' 6" Tank chassis has two radial trucks on the etch (together in one corner). However, this chassis isn't listed separately on the LRM price list. That's because the etch tool has two chassis and two bodies (both in N/S) on it. So John would be left with a body etch for each chassis he sold separately. It was designed that way to keep the tool cost down and because it was though that nobody would want a separate chassis. It isn't suitable for the GEM body kit as that has a thick cast footplate.

The LNWR 5' 6" chassis is listed , but that design had a pony truck and was designed to be built as a 0-6-2 IIRC, rather like the prototype.

I think that the Webb tank locos lasted well was probably down to being a simple and robust design, rather like the 2-4-0s they were based upon. Likewise the Watford Tank was based on the Cauliflower and both had relatively long lives.

Jol

[dal-t]

Jol,

Thanks for that - I was obviously a foot out! On closer inspection (and in daylight) the etch I has looking at last night does indeed say 5'6". Just as well, since it was (tentatively) paired with an M&L 5'6" kit. Now I just have to decide whether to 'convert' the rear axle to radial, or not, when it reaches its place at the top of the pile. I've never been entirely happy with pony trucks, all to easy for them to flap around without doing any useful work - that's also why I'm wary of Knuckles' double pivot arrangement, seems to give twice the opportunity for the axle to do its own thing, regardless of where the rest of the frames are heading.

David

[Knuckles]

That's also why I'm wary of Knuckles' double pivot arrangement, seems to give twice the opportunity for the axle to do its own thing, regardless of where the rest of the frames are heading.

David

I hear ya. I haven't started making anything for it yet but I did think mentally it might wiggle about a bit when being pushed, not so much when being pulled.

I see 3 options currently.

Fixed, double joint or single joint like pony.

Single joint may be fine but it means it will have to move in an arc and I am still unsure if that is correct for this prototype as I haven't found the text yet to give an explicit answer.

Good thing is though, It will be super easy to design the kit to have a choice of fixed axle or pony, possibly all three as if I designed a radial arm similar to my above paint drawing to be articulated you could just gum it together making a pony arm instead.

For fixed just bung the leading wheels in as normal and job done. if the single or double joint arrangement option is used then simply enlarge the axle holes out to account for the swing or cut out the horn guide lines to provide extra room or also bang a real hornblock in - possibly with overly reamed out holes (again to account for swing arc).

What ye al' thinketh?

[Will L]

Given your loco only seem to have had a radial at one end and a fixed axle at the other, a simple pony truck not carrying any body weigh is probably the easiest solution. If you provide sufficient (that is a significant amounts of) weight on the pony truck it will go both ways no problem. Arranging for it to carry real body weight is a whole lot more difficult to do successfully. I really, really wouldn't try the double jointed approach if I was you.

While I've certainly done pony trucks, honesty suggest that I mention that I've never actually fitted a real radial truck. I do have plans to do so when my 2-4-2 tanks (GER and with radials trucks at both ends in real life) get built, as the ride characteristics of what is effectively of a very long 0-4-0 do not appeal. As I can't see any real alternative to the radial axle carrying it's share of the body weight, it is only now I have real practice expedience of sprung chassis that I feel up to the challenge.

[Knuckles]

Ok thanks Will.

With my prototype K2 build I gave the bogies pick-ups but I was thinking for a future build to try a duel sprung wire method that basically pushes the bogie block downwards and providing small tabs are added will help to pull the bogie back to the centre. If the spring rubs against a metal plate then it can be made electrical by sprung contact only.

This I have never tried but I have seen something similar in one of Iain Rice's chassis books I own.

If a similar set up was provided for a pony maybe it would be a good idea? I'm talking as an option only.

This information about the J1 only having one radial and the other fixed; could someone please point to a source reference so it can be read or is it a likely estimate based on similar engines? I'm guessing the latter but no worries either way. Also if one is fixed do you think it would be the front or rear? I'm guessing information gleaned from the E1 may provide a likely answer so I could look there too.

Ok on the 2 pivot issue. I did think it might be a bit wibbly wobbly so maybe a fixed axle with a bogie arm as an optional choice providing the hole or hornblock is opened out for some swing would be best.


Sidenote: Just wondering if I have effectively derailed my own thread as it was supposed to be an announcement area for new products, and now it has devolved into a research centre for said new products!

No biggy but if those above think I should seperate things at some point and make new threads I'm happy to.

[steves17]

I have nothing to confirm that the front carrying wheels were fixed per say but i'm quite inclined to agree with others they were as the Cumbrian/Cambrian tender engines had a small wheel base-quite comparable to the 14xx GWR class and one of these was clocked pulling an auto-coach at 64mph. Again with the GWR example I can't find text confirming the carrying axel were fixed but one was sent to the curvy Lyme-Regis branch line on trial, but proved the class not suitable to replace the 3 surviving Radical Adams that operated it. Basically I wouldn't worry about the front wheel, just maybe give it a shade of side play like Airfix/Hornby did with their 14xx model, as this can negotiate most tight radius curves. Looking at both the E1 and J1 engines closely, the extended headstock aside, very little has changed below the running plate,


but you can't see much past the carrying wheels either way
Also of note are the starting date of Cambrian 'Small Passenger Class', as this 'off the peg' Sharp and Stuart design predates the invention of the Adams Axel.

Concerning the rear wheels of the J1 class though there is this line from 'The Furness Railway-A Recollection by K.J.Norman, p80.

'The rebuild designed by Mr Mason, Locomotive Superintendent at that time, consisted of lengthening the frames to carry a coal bunker, supported by a pair a radial trailing wheels and adding tanks, with a capacity of 1000 gallons of water on either side of the boiler.'

[Knuckles]

Hmm, so do you think that quote is saying that the rear is where the radial axle is but the front is fixed? I'm getting that impression.
It has been suggested a few times this is how it is but if so we can at least no be sure that it is the front axle that is fixed and not the rear. Correct conclusion opinion?

Some great pics by the way! The frames on the J1 at the bottom pic are different to BOTH the scale drawings. Why am I rolling my eyes at this? Could be class variation, basically this...

Unless I have misinterpreted the photographs. Maybe. The Rush drawing on the left seems to match the photograph better here. Or the photographs is showing a different shape completely.

[steves17]

Thats pretty much what i'm saying-front axel fixed, rear axel radial-any GWRers able to confirm the 517, Metro, 14xx & 58xx etc classes had an all fixed wheelbase? As long as you have a little slop on the front wheel to cope with fine scale and tight curves though I don't think it really matters from a prototype detail point of view, as only a camera placed along the track is going to be able to tell the difference of what is inside the frame I would also go with Will's notion about the rear wheel just being cosmetic rather than go to the effort of setting it up to carry some of the engine's weight.


It would seem Rush got a little too enthusiastic when depicting the J1's extended front on his line drawing but I think the different angles on those two photos above might be tripping you up a bit with the exact proportions. I chose them because of their general good detail quality but these might help you as an alternative, as they were almost taken from the same point of view.


Most of my books mention that the seven engines were reinvented in 1891- Nos 70A and 74 are directly mentioned but I have just re-found what I passingly mentioned on SiF a while back. 'Reflections of the Furness Railway by C.R. Davey', P51. '...one of the seven Sharp Stuart engines converted in the period 1891-96 to 2-4-2 tank engines for service on branch lines.' P19 '.....four were so converted in 1891 and a further three in 1896'.
While a stand alone source it seems too pacific to ignore and might explain the difference of the wooden buffer examples I have and this seemingly all metal example with the downward flowing curve(s).

The 1923 date is likely off as the text is describing the wrong class but it could otherwise be an example of a later mod. I have dubiously listed it as No 73 for the sec but am hoping I will be able to properly tell via the plate when I have a higher quality example in my hand to study ( actually now that i've blown it up it looks more like an 8, maybe its No 48 then ). With a few other archive photos on the way I can ( hopefully by the end of the month ) dissect more of the class's features and modifications in greater detail-My advice would be to occupy yourself with another project in the meantime to save yourself with some detail frustration.

[Knuckles]

Hi mate.

I haven't much to say on what you have other than thanks for your help and I'll continue to mull this through. What I could do is do that area like the Rush drawing then if anyone wants it to look like the other drawing then you literally get some Xuron's or whatever and cut it. Easy.

What is currently bothering me more than anything is the wheelbase issue because I would have thought the J1 would have the same driving wheelbase of the E1 as it was a rebuild. Chassis is currently set to 8' 0" like the Drawing A but I'm torn between keeping it or changing it to 7' 9" (or 8' 6" definetly will not fit in the tanks) as I'd possibly like to make an E1 after.


The bottom pic I do not think is a J1 unless it iis rebuilt. Look at the chimney, smokebox and saddle!

[steves17]

Ah bugger I zoned in on the bunker, cab and wheelbase and from there left the blinkers on because only the J1s had a 2-4-2 configuration but that engine is actually an M1 with its bogie obscured! I feel a bit silly now but that actually does help on not having to deal with some sort of odd overhaul modification, like with the Belpaire K4

Urm yeah I think we can completely can the 8' 6" wheelbase notion but I can't really tell you about the other two. I don't see the fixed or leading wheelbase changing during the tank conversion, as it would be a massive and unnecessary hassle. As the 8' fixed wheelbase is problematically too big I would just settle for 7' 10" as thats about the medium range between the Cumbrian Society plan and my Cambrian plans of the Small Passenger and Swindon O examples and its only a small margin in 76 scale.
Sorry I know you are after the final truth but thats what I would do. I can upload a few more CR photos now if you want to do some scale checks with them though.

Any Cambrian guys out there that have a plan for the Small Passenger Class, that isn't from Russell's GWR Absorbed Engines book?