Priory Road - North East Essex in BR days

[Chris Higgs]

7 hours ago, Izzy said:

A Steam Era Branch Train pt 2

 

Having converted the Farish loco wheels I’ve started on the loco by making up a chassis. Originally I sketched it out to use the common two stage gear reduction, a 30-1 worm gear followed by a 14/18T second to give around 38-1.

 

 

 

 

But following the posts on here from those using the new brass machined gearbox that takes the 30-1 worm set in a couple of similar tender locos with good results I thought that I would give that a go. It seems to run nicely and certainly has great advantage space wise. I've just got to work out how to use it with my keeper plate system. Using DCC and with another Zimo MX615 to power it I don’t foresee any slow running issues. I might try to incorporate a flywheel with the U/J's as discussed elsewhere.

 

 

 

 

Now I’ve moved on to the loco body. The footplate and cab have been made and assembled so it’s on to producing the boiler.

 

 

 

 

I’ve never rolled a boiler in 2mm so far (not expecting to mainly modelling diesels!), the N7/3 using some correct sized brass tube I had to hand, so it will be interesting. I have Cherry make rolling bars with which I’ve rolled them in 4/7mm scale over the years but that’s far too big to use here and I don’t really want to get involved making a miniature one just for this job, a nice challenge thought that might be. So a bit of simple crudity might be involved along the line…..

 

Bob

 

I modified my set of rollers using a smaller diameter rolling rod that meant I could just about do a 2mm boiler. It think you only need the bar that goes on the inside of the curve to be small enough.

 

Chris

 

[65179]

7 hours ago, Izzy said:

A Steam Era Branch Train pt 2

 

Having converted the Farish loco wheels I’ve started on the loco by making up a chassis. Originally I sketched it out to use the common two stage gear reduction, a 30-1 worm gear followed by a 14/18T second to give around 38-1.

 

 

 

 

But following the posts on here from those using the new brass machined gearbox that takes the 30-1 worm set in a couple of similar tender locos with good results I thought that I would give that a go. It seems to run nicely and certainly has great advantage space wise. I've just got to work out how to use it with my keeper plate system. Using DCC and with another Zimo MX615 to power it I don’t foresee any slow running issues. I might try to incorporate a flywheel with the U/J's as discussed elsewhere.

 

 

 

 

Now I’ve moved on to the loco body. The footplate and cab have been made and assembled so it’s on to producing the boiler.

 

 

 

 

I’ve never rolled a boiler in 2mm so far (not expecting to mainly modelling diesels!), the N7/3 using some correct sized brass tube I had to hand, so it will be interesting. I have Cherry make rolling bars with which I’ve rolled them in 4/7mm scale over the years but that’s far too big to use here and I don’t really want to get involved making a miniature one just for this job, a nice challenge thought that might be. So a bit of simple crudity might be involved along the line…..

 

Bob

 

Looking great so far Bob. I understand the desire to try new things, but the J15 boiler looks like an ideal one to produce using tube. Would not 3/8" od tube do for a 4ft 4in boiler plus clothing? Alternatively there are all sorts of weird and wonderful diameter tubes out there if you look. I found that a particular sort of brass pen kit tube was ideal for LNER B9 or Q4 boilers.

 

Regards,

Simon

[Izzy]

9 hours ago, Chris Higgs said:

 

I modified my set of rollers using a smaller diameter rolling rod that meant I could just about do a 2mm boiler. It think you only need the bar that goes on the inside of the curve to be small enough.

 

Chris

 

Ah yes, thanks for that idea. Not quite sure it would work with mine, the rollers are geared together, but I’ll give it a look and see. 
 

Bob

[Izzy]

8 hours ago, 65179 said:

 

Looking great so far Bob. I understand the desire to try new things, but the J15 boiler looks like an ideal one to produce using tube. Would not 3/8" od tube do for a 4ft 4in boiler plus clothing? Alternatively there are all sorts of weird and wonderful diameter tubes out there if you look. I found that a particular sort of brass pen kit tube was ideal for LNER B9 or Q4 boilers.

 

Regards,

Simon

Yes Simon, 3/8” would be ideal if I had any, thanks for the suggestion, but there has also been a bit of skullduggery involved in that I’ve taken the flat size off a scaled PDF and been able to drill for handrails etc before rolling, which I’m currently attempting by hand, assisted by formers and - long nose snipe pliers eek! - said crudity would be involved….   Not sure it’s working out though so getting some tube might be the sensible answer. But it’s sometimes good to try things.

 

Bob

[Chris Higgs]

2 hours ago, Izzy said:

Ah yes, thanks for that idea. Not quite sure it would work with mine, the rollers are geared together, but I’ll give it a look and see. 
 

Bob

 

On mine, the two lower rollers (on the outside of the curve) are geared together, the upper one runs free. I replaced that, I had to modify the end bearing to get it at the right height.

 

Chris

[Izzy]

6 hours ago, Chris Higgs said:

 

On mine, the two lower rollers (on the outside of the curve) are geared together, the upper one runs free. I replaced that, I had to modify the end bearing to get it at the right height.

 

Chris

 

I have a feeling that the basic principles are similar Chris but that perhaps operate in a sightly different way. Anyway, I thought perhaps digging mine out and taking a look might be worthwhile. Not having been used in quite a long while, can't remember when, it needed a good strip down and clean up. It's an 8" version with the rollers being 5/8" dia.

 

 

 

 

 

 

 

 

As you can see the two driving rollers are geared, with the third being adjustable for curvature. The sheet is inserted into the two rollers - adjustable for sheet thickness and grip - wraps itself around the top geared roller, and is why this is designed to be removable to get a get a tight roll off. I can't really see how I could reduce it's size,  the gears would prevent it, while the size of the third roller is really immaterial in general terms. Thanks for the suggestion though.

 

Bob

Edited December 20, 2022 by Izzy
add photos!

[Caley Jim]

I've always used a suitable diameter of tube.  I now draw out a development of the boiler with the various holes required, firebox opening etc, print that out and cyano it round the tube as a template for cutting a drilling.

 

Jim

[Chris Higgs]

1 hour ago, Izzy said:

 

I have a feeling that the basic principles are similar Chris but that perhaps operate in a sightly different way. Anyway, I thought perhaps digging mine out and taking a look might be worthwhile. Not having been used in quite a long while, can't remember when, it needed a good strip down and clean up. It's an 8" version with the rollers being 5/8" dia.

 

 

 

 

 

 

 

 

As you can see the two driving rollers are geared, with the third being adjustable for curvature. The sheet is inserted into the two rollers - adjustable for sheet thickness and grip - wraps itself around the top geared roller, and is why this is designed to be removable to get a get a tight roll off. I can't really see how I could reduce it's size,  the gears would prevent it, while the size of the third roller is really immaterial in general terms. Thanks for the suggestion though.

 

Bob

 

Mine (a GW Models one I think) wraps the item around the adjustable roller - my adjustable roller is at the top but I don't think that makes a difference. So minimum radius is determined by that roller, which is the one I changed.

 

Chris  

[Izzy]

I've just found a shot of the GW one. I see the difference and why you could adapt yours. Perhaps I'll make a mini version in brass sometime just for the heck of it, looks like the design is quite adaptable.

 

For now the boiler I've wrung out of 10thou will pass muster I think. You can just see the 0.3 holes for the handrail stanchions. Easier to pilot drill with this size on the flat.

 

 

 

I've just got to add the smokebox layer and outer wrapper. Normally I'd add these before fitting to the footplate but the order has changed due to various aspects such as the low height of the boiler on the footplate and design mistakes I made when cutting the latter out.

 

The cab spectacle size looks oversize because it is, I shall machine some inserts to fit to give the raised rim effect, well that's the idea.

 

Bob

 

Edited December 20, 2022 by Izzy

[Izzy]

Just found this:

 

https://www.ebay.co.uk/itm/372983562107?

 

A bit OTT price wise, I personally wouldn’t want to pay more than half that max, but shows the design can easily be made quite simply. 
 

Bob

[Nig H]

You could try rolling overlays for the smokebox this way. I've used this method for all my smokebox and boiler wrapper overlays. I prefer to use tube inside the overlays rather than roll the inner tube as it is hard to get the outer edges curved. If you want to try this practice on some scrap metal sheet or edges of etched frets first.

 

The technique is to hold the metal between the two lengths of rod/ tube and turn them against each other, drawing the metal bteween the rods and forming a curve. The diameter of the rods used governs the resulting diameter of the metal sheet.

 

 

 

 

 

 

Nig H

[CF MRC]

Or you could just turn the whole lot out of a lump of brass…

 

Tim

[Izzy]

2 hours ago, CF MRC said:

Or you could just turn the whole lot out of a lump of brass…

 

Tim

 

That would certainly help add weight easily and an alternative I hadn't considered Tim. Just pondering the difficulty or otherwise of adding the smokebox and firebox overlays given the heatsink it would be along with milling out the clearance for the gearbox and shafting. I guess it would also need screwing into place. I do tend to get stuck in a fixed ways of construction, methods that have worked previously, without considering viable alternatives, so thanks for the suggestion.

 

Bob

 

 

[Izzy]

4 hours ago, Nig H said:

You could try rolling overlays for the smokebox this way. I've used this method for all my smokebox and boiler wrapper overlays. I prefer to use tube inside the overlays rather than roll the inner tube as it is hard to get the outer edges curved.

 

Thanks for showing that Nigel. I did use a length of smaller tube to assist in basically rolling the boiler, but never thought about using two like that, so I'll certainly give that a try with the smokebox bits.

 

I've found getting the outer edges of rolled tubes curved correctly can be done by decreasing the curvature but it does depend on the size of the rollers viz the size of the roll required. I think Chris's use of a smaller roller against the others might have a beneficial impact here.

 

Bob

[65179]

An extra layer of sacrificial material longer than the overlay can help too with forming hard to curve ends.

 

Simon

[CF MRC]

1 hour ago, Izzy said:

 

That would certainly help add weight easily and an alternative I hadn't considered Tim. Just pondering the difficulty or otherwise of adding the smokebox and firebox overlays given the heatsink it would be along with milling out the clearance for the gearbox and shafting. I guess it would also need screwing into place. I do tend to get stuck in a fixed ways of construction, methods that have worked previously, without considering viable alternatives, so thanks for the suggestion.

 

Bob

 

 

I’m not precious about using 24 hr Araldite to fix on the smoke box wrapper etc. It’s what I did on Valour. 
 

Tim

[Izzy]

[Izzy]

A Steam Era Branch Train pt 3

 

With the boiler rolled and fitted work has been progressing on getting the rest of the basic loco made. The smokebox wrapper, the splashers, and the cab roof. Making sure there is sufficient clearance for the wheels under the splashers. I’m really glad now I didn’t try and used 10mm wheels, with the flange size it’s been a squeeze as it is. As with the rest of the loco this has used 5thou and 10 thou brass sheet. I know a lot of modellers prefer Nickel Silver but I get on better with brass when scratchbuilding, not so hard to cut and manipulate.

 

 

 

 

 

 

 

 

 

 

I’ve now got to the stage that requires all the bits making on the lathe, there’s quite a list, so before setting that up on the workbench I’m going to finish off the loco and tender chassis, get them to a working state.

 

Bob

 

[Izzy]

 

A Steam Era Branch Train pt 4

 

Thanks to Jerry (Queensquare) I’d intended to make the U/J’s and drive shafting as detailed in his Tucking Mill thread. However when I looked at how to produce them and their size I realised that with the small tender the J15’s had there wasn’t the space. As I had positioned the motor to allow enough room to fit the small ( 8x6mm) Zimo MX615 decoder at the rear there was only 5mm between the front of the motor and the coal space front. Not nearly enough as the short motor shaft took up half this length. And I didn’t want the U/J sticking out of the tender, all I wanted to see was a fine wire drive shaft. So what to do?

 

Having converted the Farish Ivatt 2MT to tender mounted motor using a mix of small bore brass tubing with which to make the U/J’s I went back to that approach. This is done simply with hand tools and enables the drive shafting to ‘plug-in’ to the U/J’s.

 

It revolves around some 1.5mm OD/1.0mm bore brass tube I have which is cross-drilled 0.5mm and slit lengthwise for about 2.0mm with a razor saw. The bore is a nice firm fit on the 1.0mm shafts of the 7x16 coreless motors I use. Since the shaft of the gearbox was 1.5mm the one here was soldered into a length of tube of that bore and after cross-drilling for air holes – to try and ensure no solder crept along the shaft to the gearbox bearings and locked it all up solid - was soldered to the shaft via them. The bearing/shaft was also oiled to assist here in preventing it.

 

 

The drive shaft consists of short lengths of Albion brass micro bore tube 0.8mmOD/0.4mm cross-drilled to take 0.33mm brass wire soldered in and these then soldered onto a length of suitable steel piano wire which I guess is 1/64th (0.38mm). The 0.33mm ‘pins’ will just push along the cut slot. The very end of the outer tube can be ‘squeezed’ a bit with pliers to stop it pulling out if desired once the larger 0.5mm hole section is reached. To allow some back/forth movement the section in the loco was lengthened. The smaller Albion tube was used to allow angular movement of the shafting in the U/J’s, which is pretty essential if smooth power transfer is to occur.

 

I have found that adding a torque rod to the gearbox was needed to stop it rotating around the wormwheel and causing jerky running through binding of the U/J at too extreme an angle. This is just a bit of PB wire soldered to it and fitting loosely in a slot in a frame spacer added for the purpose. Once all this had proved okay I dropped out the wheels/gearbox and painted the chassis.

 

 

 

 

Oh, having originally drilled holes for the layshaft for the two stage fixed gearbox I lengthened these and fitted a bit of sheet behind with some rivets to represent the firebox. A bit larger than the right size but better than an open hole.

 

 

The association now has a nice etch of loco brake gear which is very handy.

 

 

Here's an upside down shot showing the crude wheel retention bits. A flat strip for the tender, and some PB wire the loco. The latter held in place by the body retention screws.

 

 

Now I must get the lathe out on the workbench to do the turnery bits while I muse on how to produce some tender axleboxes, none I have found so far being suitable. I tried both the nice association 3D printed short hanger LNER and MR ones but sadly neither come close as might be expected but worth a try.

 

Bob

[2mm Andy]

Bob,

 

I think I might have some of the whitemetal GER tender axleboxes/springs that used to be available from 2mm Shop 3 if they would be of use?

 

Andy

[Izzy]

50 minutes ago, 2mm Andy said:

Bob,

 

I think I might have some of the whitemetal GER tender axleboxes/springs that used to be available from 2mm Shop 3 if they would be of use?

 

Andy

 

Oh gosh that would be useful, yes please and thank you! I thought I'd remembered seeing some somewhere. I've tried sending a PM but things aren't working at the moment so will try again later.

 

Bob

[queensquare]

1 hour ago, Izzy said:

 

Oh gosh that would be useful, yes please and thank you! I thought I'd remembered seeing some somewhere. I've tried sending a PM but things aren't working at the moment so will try again later.

 

Bob

Hi Bob, if Andy doesn’t come up trumps I’ve certainly got some GER ones you could have.

 

Jerry

[Izzy]

1 hour ago, queensquare said:

Hi Bob, if Andy doesn’t come up trumps I’ve certainly got some GER ones you could have.

 

Jerry

 

Thanks Jerry, that's very kind of you. What a great bunch of people 2mm modellers are, although I knew that already it's worth repeating. At the moment I can't send a PM to Andy after numerous attempts.....but where would we be without RMweb as this thread illustrates.

 

regards all

 

Bob

[2mm Andy]

23 minutes ago, Izzy said:

 

Thanks Jerry, that's very kind of you. What a great bunch of people 2mm modellers are, although I knew that already it's worth repeating. At the moment I can't send a PM to Andy after numerous attempts.....but where would we be without RMweb as this thread illustrates.

 

regards all

 

Bob

Hi Bob,

 

I'm at work at the moment, but I'll dig out the tender axleboxes when I get home later and send you a PM.

 

regards,

 

Andy

[Izzy]

 

A class 16

 

This recently arrived.

 

 

A Bachmann American GP40 diesel from Hatton’s second hand stock. So I’m off on another little adventure. Early on in this thread were details of a British Thomson-Houston type 1/ BR class 15 diesel I made. In common with much else I do it was a while in the planning and making, actually a couple of years from when I first found the parts I could use for the running gear to getting the loco finished and painted. Much of this time was taken with working out how to make it, a short wheelbase Bo-Bo chassis to fit inside the narrow body rather than the actual construction, which was a matter of weeks.

 

Since then I’ve considered a few times making another similar diesel only found on the exGE area, a North British type 1 or BR Class 16 and using the same basic parts. This small class of 10 pilot scheme locos actually spent their whole lives based at Stratford and were used for goods and NCPS/empty stock workings around the capital, cross London freights etc. They did occasionally stray a bit further as there are shots of them at Buntingford and I will have to use this to justify running one on my North East Essex layouts.

 

Having an even shorter wheelbase than the class 15’s and with spoked wheels any excuse has been used to leave it on the back burner, the lack of availability of the parts at reasonable cost helping here. Now, some 11 years later the GP40 came into view. At £36 and with a double shafted coreless motor along with the drive bogies needed this ‘new tooling’ model fitted the bill perfectly and so no excuses could be found to delay starting any more, if purchase of a second hand RTR diesel could be classed as ‘starting’.

 

When it came the idea was to test it to make sure it was basically okay and see how it performed as made, and then put it to one side while construction of the J15 and Thompson coaches was continued. It surprising how good intentions can get waylaid isn’t it?

 

Finding it quite acceptable I decided to ‘just’ strip it down to make sure the parts I wanted were as I hoped and expected. Well they were, and then one thing led to another.

 

 

 

 

 

 

 

 

 

After putting all the bits not needed to one side, about 75% of the loco; body, chassis mouldings, drive shafts etc. I looked at the core pieces I wanted. The two bogies with their worm housings – into which the bogies plug and rotate in, and the double-shafted coreless motor sans the flywheel, which I had removed. The motor appears similar in type and size to the Tramfambriek one sold in the 2mm SA shop 3.

 

Looking at the worm housings and bogies I discovered that in the intervening years some improvements had been made. Black coloured gears had replaced white ones while the Delrin worms on steel shafting just running in the plastic worm housing had been replaced by brass worms with the shafts now running in PB bearings.

 

 

While I studied all of this it suddenly occurred to me that an easier and simpler way of producing a chassis now presented itself thanks to the arrival of the double-shafted motor and that the even shorter wheelbase would no longer pose an issue. With sufficient Nigel Lawton belt drive parts to hand I found it appeared possible to drive each bogie separately from both motor shaft ends, doing away with the need for a layshaft joining the worm shafts together. This would also make replacing the drive belts much easier should that ever be needed, (it was with the class 15 after some 8 years), and eliminate the need to strip down the chassis to do it. What’s more I could still use the same pulley combination and thus gear reduction which I had found quite satisfactory. A native 1:17.5 of the bogies plus the 1:3.5 of the belt drive giving 1:61.25 and producing good slow running with plenty of power.

 

 

So putting everything to one side I spent the next day building and getting a running chassis. A couple of lengths of K&S ¼” brass strip, a bit of filing, drilling and tapping, a little soldering, along with fitting the pulleys on the motor and worm shafts and it was done.

 

 

 

 

Some temporary wires from the bogies and it ran. Job done! I could not believe how quick it had been when I fully expected to take a long while to sort out and get a decent result.

 

 

After some experimentation I found a spare Zimo MX622n decoder – about the same size as the newer MX617’s - would fit leaving space for adding lead weight. So that had it’s pins replaced with wires and now there is a basically complete DCC running chassis.

 

 

 

It appears it could get around a quite small radius given the amount of bogie rotation possible. I don’t know if this was part of the reason these locos were produced with such a short wheelbase, for tight curvature dockside working and such like, it’s not occurred to me before now but seems a possibility.

 

Now all I have to do is make the body …...along with new bogie side frames and work out how to produce some 10 spoked wheels suitable for use with the bogies, the design and standards being different to the current and past Farish ones using 2mm shouldered axles into offset gear muffs. However all that can wait until the body has been produced.

 

Bob