Nu Cast 2021 Pannier - Construction

[Erudhalion]

Evening all,

 

Around a year ago I bought a Nu Cast Partners GWR 2021 pannier tank kit, which has sat on various shelves and in various bags while we moved house, then country. Now we are sort of settled down in Germany, at least for the time being, I was looking at it and trying to work out what bits I need to buy to get building.

 

I am a complete novice at loco building, I have build a few Cambrian and Cooper-Craft wagons and am well on the way to finishing a brass Toad kit, and have built a white metal Peco Dennis, but that is about as far as it goes.

 

I originally was going to go for a High Level gearbox and motor, as that would avoid the need of finding a motor and gearbox from separate sources, but noticed on their website that at the moment they are not shipping outside the UK.

A Comet gearbox from Wizard models is the obvious next choice, as I need other bits from them anyway, so I cranked up the CAD and tried out a few things.

 

As far as I can tell, there is no chance I'll be able to fit the standard Comet two-stage gearboxes in, so it seems I'm left with either a single stage GB2 or 4 with the motor mounted vertically, thus:

 

 

a GB5 with a drive extender and the motor mounted horizontally:

 

 

 

 

This second option seems more appealing to me, as I can get a higher ratio (50:1 rather than 38:1), which I imagine would be more appropriate for this kind of engine. I'm assuming that the drive extender can be rigidly fixed to the main gearbox.

 

The motor (in red in the sketches) is just a rough approximation, I've been scouring Ebay for suitable motors, the main limitation being that the firebox and boiler cavity are at most just over 12mm wide.

I have heard good things about the N20 motors, and the size is right, but I can't seem to find one for sale without a gearbox. Most of the other options I've seen on various threads appear to be too wide for my application.

 

On a related note, I was wondering on the wisdom of attempting some sort of springing/compensation, but I'm not sure if I'd be able to pull it off successfully and if it would really be worth the added complication in 00.

 

Also, has anyone tried the Comet chassis jig? Or is it better to order something like Poppy's Loco Builder Box?

Edited March 2 by Erudhalion
Added better pictures

[Barclay]

Hi Branchlines still stock the Mashima 1024, at least they did  a couple of months ago, and I think this would suit this loco. very well. They also do some nice gearboxes, though they do require careful assembly. Only issue here is no website so you would have to call them. I have attached the relevant part of their catalogue, if it hasn't worked PM me and I'll send it that way. (probably not the latest version, so prices may have changed).

 

I think compensation pays dividends in terms of reliable pick up but it has to be a personal choice.

 

I have used N20s but only with the gearbox so can't comment on their general suitability I'm afraid. There are lots of decent 12vDC motors out there on ebay though they don't always have the same fixing bolts, so you may have to glue or solder them to the gearbox. I have never used a chassis jig, except for the pointed end jig-axles when setting up a compensated chassis, so they are not essential, but may make life easier...

 

M&G pdf 04.20.pdf

[Erudhalion]

The Branchlines range looks very good, however I'm trying to keep the number of different orders I'll have to make, as I'm not sure how orders from outside the EU are handled here in Germany and what extra charges might be involved.

 

I think for this project I'll go for the Comet GB5 and 1:50 drive extender because it gives me a few options should anything crop up as I build it.

While I'm at it, I'll get some sprung buffers, screw couplings and some other bits to finish off the Southwark Models brake van that has been sitting around half built in a box. I might throw in some extra pieces to spruce up a couple of plastic wagon kits I've got lying around.

 

For the motor I'll try one from Ebay, there seem to be a few options that would fit in the space available, such as these:

 

https://www.ebay.de/itm/124944998650?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D248523%26meid%3Da6d4f7b2e643402ba89939ab9d1505be%26pid%3D101195%26rk%3D5%26rkt%3D12%26sd%3D274833786599%26itm%3D124944998650%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv11WebTrimmedV3MskuWithLambda85KnnRecallV1V4V6ItemNrtInQueryAndCassiniVisualRankerAndBertRecallCPCBlended%26brand%3DMitsumi&_trksid=p2047675.c101195.m1851&amdata=cksum%3A124944998650a6d4f7b2e643402ba89939ab9d1505be|enc%3AAQAIAAABYClE7Rni7LPdZba0E4PpnN9sqdNIfzrngjJmhUj%2BPVGabI8X4okIddREUp4Q0zc2AzeQ%2BYWQSxoBqGa9J%2Bx35NrBHVFYUVGsflNyHmFJfvouFhcLtSal3PrT8uqN34xP8tTkRtMZH%2Bjfqn4MA7rMqmop9BlRs%2BvO0mz64h3%2BJZHB9h1QNDPPuDvygyflixZppThdaZQU2oNCfRLSQ85pPz0R5f7TqNCeur2Hfu0OBqHFMPW0Sxrw6BJd3KeMZfeXIQzXi5G4LjFDaR3lgzjzYm2hS0l%2BctCQRA7ocfU9Qo0CvK0rzMbjFPJuepWtVq61PCtXX1ssxfdBqVohI3adKNHndwzOUbKkonZ1G8dWxtyDBHCT9r57P8PpTrS9DVpsKMzWN6k33eFLU8qU0vzbGXdRZANlZI5RlxQ%2FRUDvswdXzjl0hnGM0FRuyjiXLKOm5589F1rw5wafWKhcZqT9284%3D|ampid%3APL_CLK|clp%3A2047675

 

https://www.ebay.de/itm/274820325076?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D248523%26meid%3D4dc7b8a6927f4b98bbaa4667bac854fc%26pid%3D101196%26rk%3D4%26rkt%3D12%26sd%3D124944998650%26itm%3D274820325076%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv5PairwiseWebWithBBEV2bAndUBSourceDemotionWithUltimatelyBoughtOfCoviewV1&_trksid=p2047675.c101196.m2219&amdata=cksum%3A2748203250764dc7b8a6927f4b98bbaa4667bac854fc|enc%3AAQAIAAABMPzGgyhK8D4QCApcBuWVQe1qsoN395NgJVWTF7eo2rfipPwdfCio0EI4F5H%2Bx0wtS8%2Fu%2Fr%2FRUxEZ1KxNtbAGuwQqNawa9Mz45LW45pYy0nujfW8XgYGJgTk3qme2u47QNo%2F%2FxademZS4lwt9N8iNYKhomzpdknC6UQ9dveo948K2iD%2B%2FCNYKwv8sWydDhMQTjdEtfCyUWRkSFwoXEDW%2BlA1o8p5r0l%2B%2BifgQbuuuNmm3mCEVRCx%2BzZ6FxCu9lJT73euE7UIDZSMdQWBM2JeNkyHc8cvz2OoxGWACRaLD7Bi8U1W0QLOaDJ4QZmUtMJg56WZZKoJwYnHWlb6geR%2Fgfj%2FooVhn9OmqRZUDk91jAEeuLe0iq4MfudM%2Bg4ZcXxuBK7Ns%2FiM1EE9tA1LJGsNaEe4%3D|ampid%3APL_CLK|clp%3A2047675

 

https://www.ebay.de/itm/275019466280?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D248523%26meid%3D4dc7b8a6927f4b98bbaa4667bac854fc%26pid%3D101196%26rk%3D2%26rkt%3D12%26sd%3D124944998650%26itm%3D275019466280%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv5PairwiseWebWithBBEV2bAndUBSourceDemotionWithUltimatelyBoughtOfCoviewV1%26brand%3DMarkenlos&_trksid=p2047675.c101196.m2219&amdata=cksum%3A2750194662804dc7b8a6927f4b98bbaa4667bac854fc|enc%3AAQAIAAABMPzGgyhK8D4QCApcBuWVQe1qsoN395NgJVWTF7eo2rfipPwdfCio0EI4F5H%2Bx0wtS8%2Fu%2Fr%2FRUxEZ1KxNtbAGuwQqNawa9Mz45LW45pYy0nujQJVHyjW1NdT7Zj3Jck52%2BQXGUGYvNZfN4KkjReFtU1El%2BLmqE9cc3jdrUrKnnK0MqewYujUuXvClYL3C434acIDKftx5gW09HkStetxusowgt%2FJYPDJ6ly5i32JLMHrFhInPLXjkwUABFiRqrdyR862zEDWCktzwNT5N2M1IT7pTcfjOFfNCcbFiEVneLEreFtqZCYiEwYtVl9RGeKtEkPGCFwKZKlX7LuL26h6u%2BDF2nLGRvr%2BcjJRLHEJT1R9vpdbzxZhd%2FFlNVt7FaFs21aaUTGkTBN8dcyoPXJAmyjk%3D|ampid%3APL_CLK|clp%3A2047675

 

Apologies for the massive links. I might order a flywheel as well, on the off chance that I can fit it in. Some drilling of holes might be necessary to fit them to the gearbox, but it should be doable.

 

I'll place the orders in the next few days and see what happens.

Edited April 20, 2023 by Erudhalion

[Barclay]

The first two are the Mitsumi M15N which has been used by a lot of modellers in recent years. I have a few in use and they seem generally good, quite slow revving and smooth. The third looks very interesting - tempting to add a couple to the collection!

[Jeff Smith]

Branchlines is the Nu Cast partner and no doubt would be happy to advise and supply a suitable g/b and motor.  Assuming you received the etched chassis with the kit it can be built rigid or compensated.  I have built several locos using the Branchlines Multibox which gives a lot of flexibility in motor/axle relationship.  Wheels, if you haven't already got them could come from the Gibson range.

[Erudhalion]

I think I will stick with a rigid chassis, mainly to avoid the complication on my first go at a loco.

 

As regards the gearbox options, I've gone with the comet option. I've also ordered some sprung buffers and fire irons from Wizard. Once I've seen how the delivery goes as regards customs and paying VAT and all that, I'll probably order some crew from Dart Castings, as I also need some buffers from them for my brake van.

 

I've also ordered one Mitsumi M15N and the open black motor, so I can try them out.

[Jeff Smith]

As this is your first chassis build I would point out that a rigid chassis built from an etched kit is actually very rigid and unforgiving - compared to a rtr chassis that will not be compensated but will have a certain degree of slop built into it which tends to assist with keeping more than just opposite-corner wheels in contact with the track.  Yes, in theory an accurately build rigid chassis with all the wheel treads dead level will pick-up on all six (in your case) wheels on dead livel track; in other words the weight distributed equally on all six wheels!  In practice this is not workable or reliable.

 

I assume your chassis kit could be built rigid, sprung or with fixed rear axle carrying the motor/gearbox with the centre and front axles supported by a centre pivoted beam.  Sprung is good but I would recommend you go with the latter.  You could also benefit from a set of axle alignment jigs to ensure your coupling rods are exactly the right length.

[micklner]

For a first time chassis builder I would not recomend springing etc , build it rigid and as simple as possible . It will be a big learning curve .

I would also recomend Markits driving wheels , Gibsons are one fit you would very lucky to get a second chance of refitting them. Markits can come on and off as many times as you like , they are expensive but worth the bit more, for ease of use.

[Jeff Smith]

Yes, agreed about Markits wheels.  Automatic gauging and quartering.

[Captain Kernow]

If building an etched chassis rigid, having a handy sheet of glass to check that all wheels are sitting 'four square' on the glass is useful.

 

[hayfield]

Am I correct in thinking that with most etched chassis the centre wheels are 1/2mm high to aid running (stop rocking) ?

 

If so would it be better to joint the coupling rods?

 

I have a Hobby Holliday chassis jig which presumably would straighten out this design feature unless hornblocks were used

[Jeff Smith]

34 minutes ago, hayfield said:

Am I correct in thinking that with most etched chassis the centre wheels are 1/2mm high to aid running (stop rocking) ?

 

If so would it be better to joint the coupling rods?

 

I have a Hobby Holliday chassis jig which presumably would straighten out this design feature unless hornblocks were used

If that is the case I cannot really see the advantage, on level track they would be clear of the track and not helping with current collection.  I can however see the point of allowing the centre axle a millemetre or so of up and down movement and then lightly springing it down - my Bachmann 57xx has this arrangement.

 

The Gibson sprung hornblocks can simulate this. The springs are not strong enough to support the weight of the loco so for an 0-6-0 the outer axles are adjusted with adjusting screws to sit square at the correct running height with the springs compressed. The centre axle screws are adjusted to allow some (1mm) upward movement against the spring.  Then under gravity and spring power the axle should sit down on the rail.....   The hornblocks are prevented from falling out by wire clips.  Jointed coupling rods are definitely required.  This arrangement also allows the outer axles some downward movement to accommodate uneven track, eg. the top of an incline etc.  Also individual axles with wheels can be dropped out.  I have used these on several P4 and 0-16.5 locos.

[Erudhalion]

2 hours ago, hayfield said:

Am I correct in thinking that with most etched chassis the centre wheels are 1/2mm high to aid running (stop rocking) ?

 

If so would it be better to joint the coupling rods?

I'll measure the chassis I've got in the kit to see. The frets include both jointed and solid coupling rods, but it is designed to work with High Level hornblocks, so I imagine the jointed ones are for that.

 

3 hours ago, Jeff Smith said:

Yes, agreed about Markits wheels.  Automatic gauging and quartering.

Luckily I ordered Markits wheels with the kit. Why I didn't also ask for a gearbox and motor at the time though escapes me...

 

2 hours ago, Captain Kernow said:

If building an etched chassis rigid, having a handy sheet of glass to check that all wheels are sitting 'four square' on the glass is useful.

 

I've got a piece of glass I use for checking wagon chassis, but I'll have to get hold of some axle alignment jigs.

[Erudhalion]

The first box of bits has arrived, with the gearbox, flywheel, sprung buffers, handrails wire and fire irons. The motors should be on their way.

 

I'm wondering about the axle alignment jigs, I know London Road Models sell sets, and Poppy's Woodtech do a plywood jig, but I was wondering if there are other alternatives I hadn't considered.

[hayfield]

Hobby Holidays did do a super chassis jig, I think these are now on special order only

[Buhar]

8 minutes ago, hayfield said:

Hobby Holidays did do a super chassis jig, I think these are now on special order only

I understand Phil at Hobby Holidays is seeing if there is enough interest to do a run of the jig.

Alan 

[Erudhalion]

I had a look at the Hobby Holidays website, and the jig does look very good, but as far as I can see rather beyond what I can justify spending at the moment.

 

Has anyone ttriethe Poppy's Woodtech Jig? That looks decent, and much more in line with my current budget.

 

Alternatively, I'm wondering if I could build something myself, although I'd have to source some 1/8" bar from somwhere.

[Erudhalion]

As I slowly gather together all the bits I need to actually start building, I have been thinking about potential identities for the loco.

 

The Nucast kit represents an engine with a B4 boiler (RCTS classification), and my general aim over the past few years has been to build stock appropriate for a hypothetical layout set in rhe Forest of Dean in the early 20s. A quick leaf through RCTS Locomotives of the GWR volume 5 shows a number of possible 2021s whitch had pannier tanks and B4 boilers in the appropriate time frame.

 

The kit comes with four different number plates, and of these, 2076 fits the criteria (fitted with a B4 boiler in June 1921 and pannier tanks in July 1921). It would be nice to know which engines were allocated to Lydney in this time period, but as far as I can tell, the only way to find out is consulting the National Archive at Kew, which isn't really a practical plan at the moment. I'm wondering how long engines remained allocated to the same shed, and weather it would be reasonable to assume an engine known to be in a certain location at a certain date would have been there 10 or so years earlier.

 

 

This thread has some info about the 1901 allocation, but that is all I can find.

 

A picture from the period would also help. I have found plenty from the BR period, both in the S&W books by Ian Pope et al. and online, but photos from the 20's seem very scarce.

 

 

Edited May 21, 2023 by Erudhalion

[T0ny]

Regarding motors, can I just add Tramfabriek motors, and for other related equipment. They have a range of small motors etc. I am just a satisfied customer. http://tramfabriek.co.uk

[6892 Oakhill Grange]

From “Great Western Railway Locomotive Allocations for 1921” by Ian Harrison the following are at Lydney in that year:

 

2024, 2025, 2029, 2032, 2040, 2041, 2053, 2068, 2069, 2080, 2084, 2085, 2087, 2093, 2138 and 2150.

 

Lydney must have needed low axle weights as the only other residents listed are Dean Goods.

 

Adrian

[Erudhalion]

Thank you!

 

That is great info, I didn't know about these books.

 

Looking at the RCTS volume, it seems that 2024, 2032, 2041, 2068, 2069, 2084, 2087, 2093 all had B4 boilers and pannier tanks at the time, so any of them are potential identities for my kit.

 

A quick search hasn't turned up any photos of the locos in question in pre war years, but I have found this picture, dated 1933, which has lots of interesting details.

 

 

The same site actually has a couple of photos of 2021s in the Forest of Dean, but both are saddle tanks and date back to the end of the 19th century.

Edited May 21, 2023 by Erudhalion
Added photo

[Erudhalion]

4 hours ago, 6892 Oakhill Grange said:

Lydney must have needed low axle weights as the only other residents listed are Dean Goods.

The Severn and Wye lines and other lines around the Forest of Dean did require low axle weights and reasonably short wheelbases, as far as I've seen, the 2021s were replaced by 16xx in BR days, and the only other classes I've seen photos of are Dean Goods and a single 14xx.

 

I've been told by the Loco department at the Dean Forest Railway that the 57xx they've got is pretty much the limit as regards rigid wheelbase, and the current DFR line was part of the S&W main line back in the day, but if I remember correctly was relaid in preservation, so other parts of the network must have been even tighter and more lightly laid.

[Erudhalion]

It has taken a while, but I have finally gathered all the bits I needed to get started.

 

I went for the Poppy's Woodtech jig, and it did it's job very well, I thought.

 

I also had to resort to fashioning my own crude imitation of a Markits wheel nut driver, as Wizard models hasn't had them in stock for a while.

 

 

The chassis went together much more easily than I thought, and seems fairly free rolling.

 

I somehow managed to swap the left and right frames, but luckily that doesn't seem to have caused serious issues. I didn't have the benefit of the half-etched locating slots for the rear guard irons as they are now on the inside, but I managed to fix them in the right position. However, the half etched  detail on the brake and reverser brackets is also now on the inside, while there are some markings for CSB mountings on the outside which might need filling in.

 

Next I tackled the gearbox. I had ordered a Mitsumi motor with the other black motor as a backup. THIS was lucky, as the Mitsumi transmographied into a 4 digit LCD display on its way here, and then the replacement got lost in the post.

 

I encountered a couple of problems putting the gearbox together. The smallest helical gear is quite a tight fit on its axle. The instructions suggest leaving it loose and fixing the axle to the gearbox sides, but at the moment I've left the axle loose and it goes around with the gear.

For some reason, I was forced to file back the inside faces of the bearings i order to slot middle gear between the sides of the gearbox. Luckily the drive extender went together without issues, although I did choose to file the lower corner back a bit to ensure that it would be covered by the ashpan when viewed from the side. For the moment the drive extender is free to rotate while I sort out the clearances in the body and decide on the position.

I also ended up epoxying the motor to the gearbox, which was not what I would have ideally wanted, but considering that I couldn't find suitable mounting screws and was a bit concerned about drilling holes into the motor, it seemed the best solution.

 

Once the other chassis details went on, I mounted the gearbox and tested the whole thing out. It was a little stiff at firss, but quickly loosened up with a few minutes of running.

 

 

A quick test with some of the main body castings revealed that there is a lot of metal in the area where the boiler meets the cab front, which makes the vertical motor position I talked about in my original post totally unworkable. It also gets in the way of mounting the motor horizontally, but I think I can file away enough metal to get it to fit.

 

I also still need to permanently fit the connecting rods, and think of the best way to attach the balance weights. Im leaning towards epoxy at the moment, but I don't know if there is a better way.

[Erudhalion]

After a reasonably fruitful evening a couple of days ago, I have got the footplate and splashers assembled. The footplate was not remotely flat, but I have got to a poit where I think it looks all right.

 

There was a fair bit of hacking away at the inside of the splashers to get enough clearance for the wheels and crankpins, especially on the middle drivers. It all seems to be ok and to turn smoothly, but my testing facilities are a bit limited at the moment. Once I've worked out how I want to do the pickups I'll deploy my best German and see if I can use the test track in my local model shop.

 

Before I do that though, I need to sort out the problem I mentioned in my previous post and make some space in the firebox area for the gearbox. Ideally, I would like the lower side of the motor to sit parallel to the running plate and at least aligned with where the bottom of the boiler should be, something like this:

 

 

However, the rear end of the gearbox needs to go exactly where the back of the firebox, rear tank support and front of the cab are. These three pieces all need soldering together, and form a pretty substantial chunk of whitemetal, as you can see when I hold them together with tweezers.

 

 

 

Without modification, with the back of the gearbox as far back as it goes, the motor has to lean forward like this:

 

 

All going well, I should be able to file away the lower front portion of this chunk and fit everything in. I was also thinking that I could glue a curved piece of plasticard to the bottom of the motor to act as the bottom of the boiler barrel, obscuring the motor ad flywheel from view, but I'll have to wait and see if that is feasible.

 

I can then solder the drive extender to the main gearbox, and think of a way of holding the motor and gearbox in the correct position while also allowing the body to be removed.

[cctransuk]

19 hours ago, Erudhalion said:

After a reasonably fruitful evening a couple of days ago, I have got the footplate and splashers assembled. The footplate was not remotely flat, but I have got to a poit where I think it looks all right.

 

There was a fair bit of hacking away at the inside of the splashers to get enough clearance for the wheels and crankpins, especially on the middle drivers. It all seems to be ok and to turn smoothly, but my testing facilities are a bit limited at the moment. Once I've worked out how I want to do the pickups I'll deploy my best German and see if I can use the test track in my local model shop.

 

Before I do that though, I need to sort out the problem I mentioned in my previous post and make some space in the firebox area for the gearbox. Ideally, I would like the lower side of the motor to sit parallel to the running plate and at least aligned with where the bottom of the boiler should be, something like this:

 

 

However, the rear end of the gearbox needs to go exactly where the back of the firebox, rear tank support and front of the cab are. These three pieces all need soldering together, and form a pretty substantial chunk of whitemetal, as you can see when I hold them together with tweezers.

 

 

 

Without modification, with the back of the gearbox as far back as it goes, the motor has to lean forward like this:

 

 

All going well, I should be able to file away the lower front portion of this chunk and fit everything in. I was also thinking that I could glue a curved piece of plasticard to the bottom of the motor to act as the bottom of the boiler barrel, obscuring the motor ad flywheel from view, but I'll have to wait and see if that is feasible.

 

I can then solder the drive extender to the main gearbox, and think of a way of holding the motor and gearbox in the correct position while also allowing the body to be removed.

 

You may well find it easier to remove the bulk of the whitemetal from the individual components BEFORE soldering them together; then finish off with a coarse file after soldering.

 

CJI.

Edited March 8 by cctransuk