Any Question Answered

[Lacathedrale]

@nick_bastable I think you need to re-host that image or convert it to a link? it's showing up as it can't be displayed.

[nick_bastable]

4 minutes ago, Lacathedrale said:

@nick_bastable I think you need to re-host that image or convert it to a link? it's showing up as it can't be displayed.

its from another forum and may depend on been a member have removed 

Nick B

[2mm Andy]

This is Gareth's O Class;

 

http://www.worsleyworks.co.uk/Image-Pages/Image_N_SECR-0.htm

 

Andy

[Gareth Collier]

Howdy,

Yep, my O class uses a Dapol Terrier chassis in the tender as wheel spacing and size is spot on and you can even leave a coal space. The drivers are from a Dapol prairie tank and really need replacing with something more see through but I've not got round to it yet.

The Q class is also doable as there is already a 3D print available for a Metropolitan Railway C class which is basically a Q.

https://www.shapeways.com/product/WG3NK7TAT/b-148fs-metropolitan-c-class-0-4-4t-loco?optionId=153771829&li=ostatus

I back dated it by switching the dome and it runs on a heavily modified Farish prarire chassis with a motor from a Terrier.

 

Edited July 28, 2020 by Gareth Collier

[bécasse]

I have said it before, but I will say it again as it is worth saying. The SER Q class is a particularly difficult loco to model because getting it to balance properly is a problem. It would seem that this was almost certainly a problem with the prototype too as there were a number of (unsuccessful) experiments changing the bogie and its wheelbase and  balance point, and the bogie wheels, in an attempt to overcome the problem. Eventually the problem was solved by electrifying the majority of services whose traction the Q class provided and withdrawing the class en mass (which was most un-Southern Railway like at the time). The H class development of the Qs didn't suffer from the balance problem, (once bitten, twice shy?) and lasted almost until the end of steam.

[Gareth Collier]

5 minutes ago, bécasse said:

I have said it before, but I will say it again as it is worth saying. The SER Q class is a particularly difficult loco to model because getting it to balance properly is a problem. 

Nope, plenty of room in the boiler/smokebox and side tanks to ensure there is enough weight over the drivers and a spring on the bogie to help transfer weight forwards to ensure good haulage. Really wasn't hard to do at all.

[queensquare]

16 minutes ago, bécasse said:

I have said it before, but I will say it again as it is worth saying. The SER Q class is a particularly difficult loco to model because getting it to balance properly is a problem.

 

0-4-4Ts aren't a major problem in 2mm. The rear bogie means the motor , which weighs comparatively little, can sit at the back, below the window line driving the rear axle. As Gareth says , this leaves plenty of room in the boiler and side tanks for weight over the drivers, aided by lightly springing the bogie.

 

Jerry

[bécasse]

3 hours ago, queensquare said:

 

0-4-4Ts aren't a major problem in 2mm. The rear bogie means the motor , which weighs comparatively little, can sit at the back, below the window line driving the rear axle. As Gareth says , this leaves plenty of room in the boiler and side tanks for weight over the drivers, aided by lightly springing the bogie.

 

I realise that that is generally true for 0-4-4Ts in 2FS, but the Q still presents problems, not least because the side tanks barely come forward of the rear axle and the boiler/smokebox is quite small in diameter. I am not saying that it can't be done and I am sure that someone with your experience wouldn't need to give it too much extra thought, but it certainly isn't a prototype that I would recommend to a relative newcomer - and I have known one very skilled 4mm SECR modeller give up on one in despair.

[Gareth Collier]

45 minutes ago, bécasse said:

 

I realise that that is generally true for 0-4-4Ts in 2FS, but the Q still presents problems, not least because the side tanks barely come forward of the rear axle and the boiler/smokebox is quite small in diameter. I am not saying that it can't be done and I am sure that someone with your experience wouldn't need to give it too much extra thought, but it certainly isn't a prototype that I would recommend to a relative newcomer - and I have known one very skilled 4mm SECR modeller give up on one in despair.

I'm not trying to offend but I am wondering if you've tried to build one, are just assuming or basing your opinion on one 4mm example someone else tried to build?

My Q a few posts up works absolutely fine and didn't cause any problems, it was easy to get plenty of weight over the drivers. The smokebox may be small but the 3D print is very thin and by springing the rear bogie you can add weight the full length of the tanks.

Rather than trying to put someone off a build with second hand anecdotes we should be encouraging a build that in the world of 2mm/N isn't as problematical as you suggest. 

[queensquare]

38 minutes ago, Gareth Collier said:

I'm not trying to offend but I am wondering if you've tried to build one, are just assuming or basing your opinion on one 4mm example someone else tried to build?

My Q a few posts up works absolutely fine and didn't cause any problems, it was easy to get plenty of weight over the drivers. The smokebox may be small but the 3D print is very thin and by springing the rear bogie you can add weight the full length of the tanks.

Rather than trying to put someone off a build with second hand anecdotes we should be encouraging a build that in the world of 2mm/N isn't as problematical as you suggest. 

 

Fully agree, I can't see that the Q is much different to any other 0-4-4T.

 

Jerry

[Caley Jim]

Modern, light coreless motors will certainly make life easier.  Both my 0-4-4T's have old iron cored motors which project back into the cab and bunker and I had to put fairly strong springing onto the bogie to hold the back up.

 

Jim

[Izzy]

Although I understand the need for a swinging pony truck type bogie when quite tight radius curves are used could I ask why fixed bogies aren’t used in 2FS - or maybe they are - which will support the end of loco when more generous track curvature is employed. In this manner the bogie pivot acts as the fulcrum point with most of the loco weight thus acting on the drivers for best traction.

 

Izzy

[Caley Jim]

On both of mine the bogie pivots on a bolt. On one the bolt is fixed in the loco spacer with a slot in the bogie stretcher and on the other the bolt slides in a slot in the loco spacer. Both have dinner springs which support the rear of the loco, help to centre the bogie and carry current from the bogie wheels to the loco. Works well on both. 

 

Jim

[Nick Mitchell]

10 hours ago, Izzy said:

Although I understand the need for a swinging pony truck type bogie when quite tight radius curves are used could I ask why fixed bogies aren’t used in 2FS - or maybe they are - which will support the end of loco when more generous track curvature is employed. In this manner the bogie pivot acts as the fulcrum point with most of the loco weight thus acting on the drivers for best traction.

 

Izzy

 

Not sure what you mean by "fixed". I think you will always need some vertical and some sideways movement of the bogie.

The way I have built loco bogies (3 so far, all from Nigel Hunt kits) uses a fixed stem as the pivot, with a spring-loaded washer pressing down on top of the bogie. The bogie has a slot, rather than a hole.

 

Part 11 of my Jubilee video marathon (starting from about 10 minutes in) discusses in detail how this method works.

 

Here are a few pictures of the most recent one one I've made while under construction - this time a Fowler 2-6-4 (Nigel's latest kit):

 

The completed bogie, with a slot in the frame stretcher:

 

On the left edge of the next picture, you can see the top of the bogie pivot, which has a 14BA nut embedded within it:

 

Below are two turned pivots for this loco. The longer one is the bogie pivot. The other is the pony truck pivot (which is hidden from view in the picture above). The holes up the middle are clearance for 14BA bolts to pass through and engage in the nuts captive in the wider section at the top. Nigel sells a cast version of these pivots.

In the case of the bogie pivot, a Farish old-style coupling spring (still available as spares) slides over the outside of the stem and provides down force.

 

The pony truck on this particular loco is not sprung. It rotates around the outside of the turned pivot and is retained with a flanged bolt.

I may have over-engineered this - a simpler solution would have been to have a 12BA stud as the pivot, but I prefer to have a smooth bearing surface rather than a something thin pivoting around a threaded section. This way also means the bolt can be done up tight.

 

All these locos happily negotiate tight radius points (A6). The amount of movement required is actually quite small.

[Izzy]

2 hours ago, Nick Mitchell said:

 

Not sure what you mean by "fixed". I think you will always need some vertical and some sideways movement of the bogie.

The way I have built loco bogies (3 so far, all from Nigel Hunt kits) uses a fixed stem as the pivot, with a spring-loaded washer pressing down on top of the bogie. The bogie has a slot, rather than a hole.

 

Part 11 of my Jubilee video marathon (starting from about 10 minutes in) discusses in detail how this method works.

 

Here are a few pictures of the most recent one one I've made while under construction - this time a Fowler 2-6-4 (Nigel's latest kit):

 

The completed bogie, with a slot in the frame stretcher:

 

On the left edge of the next picture, you can see the top of the bogie pivot, which has a 14BA nut embedded within it:

 

Below are two turned pivots for this loco. The longer one is the bogie pivot. The other is the pony truck pivot (which is hidden from view in the picture above). The holes up the middle are clearance for 14BA bolts to pass through and engage in the nuts captive in the wider section at the top. Nigel sells a cast version of these pivots.

In the case of the bogie pivot, a Farish old-style coupling spring (still available as spares) slides over the outside of the stem and provides down force.

 

The pony truck on this particular loco is not sprung. It rotates around the outside of the turned pivot and is retained with a flanged bolt.

I may have over-engineered this - a simpler solution would have been to have a 12BA stud as the pivot, but I prefer to have a smooth bearing surface rather than a something thin pivoting around a threaded section. This way also means the bolt can be done up tight.

 

All these locos happily negotiate tight radius points (A6). The amount of movement required is actually quite small.

Yes, that’s what I meant, a fixed stem on which the bogie either just pivots or can move sideways a bit in a slot as per yours, but can’t rise upwards, but can go down, so the weight of the loco at the rear is supported. Generally I have applied the principle to both 0-4-4 & 4-4-0’s with a split-axle beam compensated bogie. This has been in 4mm & 7mm, not 2mm to date as I am now (mostly) diesel/electric modelling, which is why I just queried the normal methods used. I got the impression, which is obviously wrong, that the bogies were just hung on the chassis RTR style with a double pivot pony truck type, which of course gives rise to ‘nodding donkey’ type running qualities if not careful.

 

Izzy

[Nick Mitchell]

3 hours ago, Izzy said:

... which is why I just queried the normal methods used. I got the impression, which is obviously wrong, that the bogies were just hung on the chassis RTR style with a double pivot pony truck type, which of course gives rise to ‘nodding donkey’ type running qualities if not careful.

 

You certainly can find 2mm bogies on a double pivot like that. I have some Association Black 5 kits to build in the (hopefully not-too-distant!) future, which feature this arrangement.

With Bob Jones behind the design, I have no worries about their eventual running qualities.

[Izzy]

2 hours ago, Nick Mitchell said:

 

You certainly can find 2mm bogies on a double pivot like that. I have some Association Black 5 kits to build in the (hopefully not-too-distant!) future, which feature this arrangement.

With Bob Jones behind the design, I have no worries about their eventual running qualities.

 

Oh yes, different wheel configuration so different fun and games!

 

Izzy

[Donw]

Could the answer be the 4mm Modeller was trying to keep the cab clear and thus had the motor in the boiler.  I expect some clever clogs will now post a picture of a 2mm 0-4-4t with a clear fully detailed cab. I remember from my EM days the big issues was with cast whitemetal kits where the weight of the cab and bunker tends to be greater than the smokebox and chimney end so the loco wants to sit down. It is much less of a problem with etched, Plastic moulded or 3D printed bodies where less counterbalancing weight is needed. Even a 0-4-2 can show the same problem if the rear wheel  has vertical play.

 

Don

 

[bécasse]

12 hours ago, Donw said:

Could the answer be the 4mm Modeller was trying to keep the cab clear and thus had the motor in the boiler.  I expect some clever clogs will now post a picture of a 2mm 0-4-4t with a clear fully detailed cab. I remember from my EM days the big issues was with cast whitemetal kits where the weight of the cab and bunker tends to be greater than the smokebox and chimney end so the loco wants to sit down. It is much less of a problem with etched, Plastic moulded or 3D printed bodies where less counterbalancing weight is needed. Even a 0-4-2 can show the same problem if the rear wheel  has vertical play.

 

The 4mm modeller, who had a fleet of exquisite hand-built SECR model locos in EM (because he had started pre-P4), did indeed try to keep the cab as clear as possible. His Q was OK running on its own but adding a train behind the bunker tipped the balance and took just enough weight off the driving wheels to make it impractical to use the loco for its intended purpose. As I said, reading through the history of the real locos, it is now clear that they suffered from the same problem - the SECR had a solution, electrification, but that got scuppered, at least in its intended form, by the Great War, it does though explain why the SR gave electrification priority to routes worked by the Qs.

[queensquare]

I have a load of the long unavailable but much missed Woodhead transfers, many of which have dried out and are unusable. I seem to remember reading somewhere a method of revitalising them but can't for the life of me remember where.

Any suggestions?

 

Jerry

[nick_bastable]

Jerry

 

I would suggest https://www.amazon.co.uk/Microscale-BMF128-Micro-Sol-solution/dp/B0006O9K5Q

 

they do three flavours  from memory 

 

Nick B

[garethashenden]

6 hours ago, nick_bastable said:

Jerry

 

I would suggest https://www.amazon.co.uk/Microscale-BMF128-Micro-Sol-solution/dp/B0006O9K5Q

 

they do three flavours  from memory 

 

Nick B

 

Close, but for old decals the product that's really called for is Liquid Decal Film. Brush it on, let it dry, use as a waterslide transfer. Be careful with the brushing on though, it can add thickness quickly.

https://www.amazon.co.uk/MicroScale-Industries-Liquid-Decal-Film/dp/B06XNZ8Y3H/ref=sr_1_1?dchild=1&keywords=liquid+decal+film&qid=1596688229&sr=8-1

[queensquare]

Many thanks gents, I've just ordered some

https://www.ebay.co.uk/itm/Microscale-30ml-Liquid-Decal-Film/323747939798?hash=item4b60e185d6:g:WGoAAOSw8ihclLL~

 

Jerry

[Kylestrome]

15 hours ago, queensquare said:

I have a load of the long unavailable but much missed Woodhead transfers, many of which have dried out and are unusable. I seem to remember reading somewhere a method of revitalising them but can't for the life of me remember where.

Any suggestions?

 

Jerry

 

Jerry, I also have a load of Woodhead transfers but, as far as I can ascertain, the only thing that has ‘dried out’ is the tackiness that was an aid to positioning. They are still viable as normal waterslide transfers, they just need to be wetted and applied upside down and then you slide off the backing paper. 

 

David

[queensquare]

3 minutes ago, Kylestrome said:

 

Jerry, I also have a load of Woodhead transfers but, as far as I can ascertain, the only thing that has ‘dried out’ is the tackiness that was an aid to positioning. They are still viable as normal waterslide transfers, they just need to be wetted and applied upside down and then you slide off the backing paper. 

 

David

 

Hi David, I tried that and it didnt work, they didnt stick. It seems as if the glue has dried up and cant be revitalised.

 

Jerry