Hornby - New tooling - Large Prairie

[PMP]

11 hours ago, john dew said:

Well they would hardly video it stalling would they?

 

No for that video I wouldn’t expect them to.

 

However I’m pretty certain Tony Wright would have mentioned deficiencies in their running quality in his review, I don’t recall any, and it shows one of them running at good speed on an eight coach train with a variety of stock, likely to be heavier than a similar train of RTR stock.

 

Yourself and a couple of others have mentioned the track you’re using in some cases is not the best, or as good as it should perhaps be, I sometimes wonder if that (with no disrespect) is overlooked by readers.

brgds

nb the set track/Kato and some of the streamline Ive used whilst testing also isn’t as good as it could be.

 

 

 

[Ruffnut Thorston]

With reference to the earlier discussion on the Hornby 2721 pannier tank Locos...
 

 

Earlier model 2721 with moulded handrails on the bunker and front of the tank tops.
 

 

This one has been modified a bit, and repainted.

 

 

Later Railroad version (rear coupling changed) with separate handrails on the bunker and tank tops. Later main range locos also have these handrails, and the printing includes the route availability and power class yellow disk.

 

 

Main range version, with some slight  modifications...

 

 

Edited November 8, 2020 by Ruffnut Thorston
Housekeeping

[tomparryharry]

Very nice. Now that Hornby have released the large prairie, I wonder if they  (Hornby)  are at a loose end? If so, then can they  (Hornby ) be persuaded to upgrade the venerable 27xx pannier tank?

 

Fair play to them, they've gone most of the way: It seems a shame not to go the whole hog. Little things, like a proper chimney, different drive to allow light under the boiler, brake pull rods,  lamp irons, fire iron brackets, that sort of thing. 

 

In an ideal world, the existing 2721 model can remain in the Railroad range. The proposed  (revised ) pannier can easily live in it's own right. After all, it's now well-known that people can & will pay the premium for the fuller-fat models. 

 

For Hornby, if you are reading this, then leave the top feed off  The Western managed to make over 1,000 panniers before the top feed came along.... Leaving it off allows you to fully exploit all of the different ages of the pannier, from about 1904, all the way to the present day.    

 

You know it makes sense.....

[melmerby]

6 minutes ago, tomparryharry said:

Very nice. Now that Hornby have released the large prairie, I wonder if they  (Hornby)  are at a loose end? If so, then can they  (Hornby ) be persuaded to upgrade the venerable 27xx pannier tank?

 

Fair play to them, they've gone most of the way: It seems a shame not to go the whole hog. Little things, like a proper chimney, different drive to allow light under the boiler, brake pull rods,  lamp irons, fire iron brackets, that sort of thing. 

 

In an ideal world, the existing 2721 model can remain in the Railroad range. The proposed  (revised ) pannier can easily live in it's own right. After all, it's now well-known that people can & will pay the premium for the fuller-fat models. 

 

For Hornby, if you are reading this, then leave the top feed off  The Western managed to make over 1,000 panniers before the top feed came along.... Leaving it off allows you to fully exploit all of the different ages of the pannier, from about 1904, all the way to the present day.    

 

You know it makes sense.....

The correct wheelbase & hence loco length would be nice

How about a saddle tank version?

Like most of the earlier panniers they started out as saddletanks with round top fireboxes and gained panniers with the change to Belpaires.

Some saddle tanks even lasted into BR days.

IIRC not all non top-feed locos were converted, even once they became standard for new builds

 

[tomparryharry]

Hello Keith, you rather made my point.  True, the chassis was-is  inaccurate, but that was then.  Nowadays, Hornby usually turn out first-rate stuff. By that line of reasoning, something along the lines of an earlier era pannier or saddle tank would find favour with most of us. 

 

Polite discussion will win through, I'm sure.  

[The Johnster]

While we are diverting into 2721 territory...

 

The chassis is inaccurate in terms of axle spacing (which means that the splashers are as well) because it was originally the generic Jinty R52 chassis which was incorrect for a Jinty because it used the same coupling rods as the Rovex Black Princess.  AFAIK, this chassis and later versions that have had to preserve the R52 axle spacing to fit the incorrect splashers on the body toolings, are not accurate for anything anywhere, but there must be some prototype somewhere in the world that they are correct for, perhaps in H0 or 0-16.5.  Xmas competition; find a correct prototype for the R52 and later version generic 0-6-0, prize to be announced February 30th.

 

Other problems with the Hornby 2721; boiler skirts (not so noticeable in a black livery), massive couplings, incorrect cab roof, moulded smokebox dart, open cab with no representation of wooden cab floor, conical tapered chimney (should be parallel, probably conical to facilitate release from mould), poor representation of safety valve cover (upturned flower pot).  The rest is not all that bad, but mine has had new buffers and lamp irons added.  It is AFAIK the only RTR pannier that does not come with a top feed moulded in.

 

So, I am in full agreement with Ian TPH on this one, but less hopeful about Hornby or anyone producing a new tooling for it.  Hornby's original was a quite brave move to pre-grouping RTR, but the company has form with this going back to LOTI and the shorty clerestories.  One gets the feeling thought that this was always considered as a starter train set loco, a role in which it has appeared several times, rather than anything to be taken seriously by 'proper' modellers (whatever they are) (me, of course, everybody else is doing it all wrong...).  It's a toy, and some of us have made what we think are acceptable layout models out of it, but I for one would bin mine in a heartbeat if a retooled model to current RTR standards turned up at Cwmdimbath...

 

We can live in hope, though, and we are listened to sometimes...

 

With or without, but preferably without, top feed.  Stafford Road Works, 3D printers who sell through Shapeways, do a saddle tank body to fit the R52 style chassis which they say can represent 1701, 1854, or2721.  I can recommend them in general terms, having used some of their printed GW bogies; satisfied customer no connection.

 

 

[john dew]

11 hours ago, St Enodoc said:

Ditto for me on SMP track with handbuilt points.

 

As a long time follower and fan of John' s I am not surprised by this.

 

However his success does rather support my suggestion that the Large Prairie has required more than the usual amount of attention by a number of modellers to ensure it runs satisfactorily.

 

On 12/07/2020 at 00:21, St Enodoc said:

I had a good look at the Prairie last night. I adjusted the back-to-backs then had a close look at the loco on the rolling road. There was nothing obviously wrong and no clear reason for the wobble, other than rather a lot of side play on all the wheels. This, coupled with the wheel profile that appears to have very little conicity and the very flat profile of the rolling road rollers, means that hunting is almost inevitable.

 

I therefore tried the loco on the layout today, with a temporary DC feed. It behaved much better, especially when hauling a train. Some wobble was still there but not as much as on the rolling road and at moderate speeds it was barely noticeable.

 

So, I've decided not to send it back and will carry on with chipping, renumbering, new couplings and so on. I think I'll also restrict the side play on the front and rear drivers a little. If I can find any, I'll use the old trick of Peco fibre washers with a slit cut in them so that they can be forced over the axles. If not, the same arrangement with bits of styrene will do.

 

A number of folk have commented on the lack of vertical movement on the pony trucks. The rear one is just about OK but the front one needs more. The easiest way to do this will be with a slightly longer M2 screw and washer.

 

 

 

How many releases have necessitated a number of modellers changing the front pivot screw or alternatively filing down the pony truck mounting?

 

Having re read the July emails in this lengthy thread I am satisfied that a reasonable number of modellers did experience some issues with this release.

 

Regards from a cold but sunny Vancouver

 

 

[Butler Henderson]

On 03/11/2020 at 17:33, The Johnster said:

And they could be made adjustable!  The Airfix were a brave attempt, and work if they are meticulously maintained to be crud free, but are a bit too delicate for general use. 

The main problem with the Airfix ones was the current draw of the motor could exceed the current capacity of the springs in the sprung plungers.

 

7 minutes ago, The Johnster said:

While we are diverting into 2721 territory...

 

The chassis is inaccurate in terms of axle spacing (which means that the splashers are as well) because it was originally the generic Jinty R52 chassis which was incorrect for a Jinty because it used the same coupling rods as the Rovex Black Princess. 

The 2721 actually uses the 1978 Jinty Chassis, plastic keeper plate with brake blocks and wheels/axles drop in place rather than the axle being pushed through the chassis block.

[tomparryharry]

Sorry folks, but I'll return to my earlier post. The point I was making is that the Hornby chassis is currently 'all wrong'. That we know;  everybody and his god  know. What I was driving at is persuading Hornby to make a better model, pure & simple. Listing the faults won't help here one iota. In fact, it'll probably go against anyone trying to see, or achieve, a decent RTR model of an early-era pannier. 

 

Grumbling about 'this is wrong, and that is wrong' does no-one a favour.  Instead, try saying:- "You can improve it by doing..."

 

There will be nothing, if a manufacturer gets a hostile response.  

Mild rant over.

Ian.

[melmerby]

I've done a bit more investigating my 2 new Hornby Prairies.

Their performance is nigh on identical.

However they both stop on the same piece of trackwork at a scale 15mph.

It is a crossover made of two medium radius LH code 75 Peco Electrofrogs.

All the rails are live and as far as I can determine the track is flat.

 

No other loco stops there, even at slow speeds.

This OBB class 2060 miniature 4 wheel shunter, which weighs a mere 100gms or so negotiates the crossover without incident.

 

 

I have checked the wipers on the first Prairie and I know they are all making good contact with the wheel backs.

To complicate matters there is another crossover made of 2 similar but RH points at the other end of the run round loop and the Prairies negotiate it seamlessly as well as various double slips, 3 ways etc. It's just the one crossover which is causing grief.

 

[tomparryharry]

Hello Keith, may I suggest slightly tweaking the toe of the point?  Taking 2 pairs of jewellers pliers, grip the blade fairly firmly, and 'tweak' the leading edge of the point blade outwards, only by a tiny fraction. I did encounter this on my shunting puzzle, and it drove me up the wall. The point to all intents & purposes was entirely clean. But still it failed. Everything would work over it, except a Bachmann 03.  In desperation, I gave it a slightest tweak, and hey Presto! Remember that you'll need to slightly the other toe, vis-a-vis  to its parent stock rail.

 

Cheers,

Ian.

[melmerby]

7 hours ago, tomparryharry said:

Hello Keith, may I suggest slightly tweaking the toe of the point?  Taking 2 pairs of jewellers pliers, grip the blade fairly firmly, and 'tweak' the leading edge of the point blade outwards, only by a tiny fraction. I did encounter this on my shunting puzzle, and it drove me up the wall. The point to all intents & purposes was entirely clean. But still it failed. Everything would work over it, except a Bachmann 03.  In desperation, I gave it a slightest tweak, and hey Presto! Remember that you'll need to slightly the other toe, vis-a-vis  to its parent stock rail.

 

Cheers,

Ian.

Hi Ian

Unfortunately I don't think that's where the problem is.

I use Tortoise point motors with the overcentre spring removed from the point as the blades are held very firmly against the stock rails.

It actually stops as it is crossing between the two points and has negotiated the first set of blades by then.

 

[31A]

7 minutes ago, melmerby said:

Hi Ian

Unfortunately I don't think that's where the problem is.

I use Tortoise point motors with the overcentre spring removed from the point as the blades are held very firmly against the stock rails.

It actually stops as it is crossing between the two points and has negotiated the first set of blades by then.

 

 

Are the frogs of the points switched from switches on the point motors?

 

If not, is it possible that one of the loco wheels (even one of the pony truck wheels) is bridging the gap between the stock rail and one of the blades, and making a short circuit?

 

[Budgie]

10 hours ago, melmerby said:

I've done a bit more investigating my 2 new Hornby Prairies.

Their performance is nigh on identical.

However they both stop on the same piece of trackwork at a scale 15mph.

It is a crossover made of two medium radius LH code 75 Peco Electrofrogs.

All the rails are live and as far as I can determine the track is flat.

 

Are you absolutely certain the track is flat? Maybe all the drivers on one side are being raised just enough off the rail by the pony trucks being too "stiff" to cause the loco to stall.

 

When it stops, what happens if you push the loco to one side, to make the drivers contact the rail? If nothing happens pushing it one way, try the other.

 

What happens if you loosen the screws fixing the pony trucks by half a turn?

[tomparryharry]

Hi Keith, can I try another suggestion? Try a wander lead, from a known + or - feed, and touch the rails.  Mind you, you might have tried this before....

 

Look for sideways play across the axles. My Heljan 95xx had this problem. working across a set of points, where the frames & pickups go one way, and then another  direction in quick succession. It might cause a 'dwell' , just at that point. 

 

If all of your locomotive stock can negotiate the pair, then it might well be the model in question.  Without causing offence, does it run backwards over the problem area?

 

Cheers,

Ian.

 

PS. Writing this, I've remembered to make a LV leadlamp myself. I lent it out, never to return.... 

[Covkid]

13 hours ago, melmerby said:

I've done a bit more investigating my 2 new Hornby Prairies.

Their performance is nigh on identical.

However they both stop on the same piece of trackwork at a scale 15mph.

It is a crossover made of two medium radius LH code 75 Peco Electrofrogs.

All the rails are live and as far as I can determine the track is flat.

 

No other loco stops there, even at slow speeds.

This OBB class 2060 miniature 4 wheel shunter, which weighs a mere 100gms or so negotiates the crossover without incident.

 

 

 

I have checked the wipers on the first Prairie and I know they are all making good contact with the wheel backs.

To complicate matters there is another crossover made of 2 similar but RH points at the other end of the run round loop and the Prairies negotiate it seamlessly as well as various double slips, 3 ways etc. It's just the one crossover which is causing grief.

 

 

 

If both prairies negotiate one crossover without bother, but dither on an identical configuration, then it has to be a track issue.  I understand where you are going with the Austrian diesel, but I had one and they stick to the rails very well.

 

Address your track  

Edited November 9, 2020 by Covkid
typo

[melmerby]

4 hours ago, Budgie said:

Are you absolutely certain the track is flat? Maybe all the drivers on one side are being raised just enough off the rail by the pony trucks being too "stiff" to cause the loco to stall.

When it stops, what happens if you push the loco to one side, to make the drivers contact the rail? If nothing happens pushing it one way, try the other.

What happens if you loosen the screws fixing the pony trucks by half a turn?

The pony trucks are floppy, that was an early mod I did to the first one. So they aren't the cause.

 

47 minutes ago, Covkid said:

If both prairies negotiate one crossover without bother, but dither on an identical configuration, then it has to be a track issue.  I understand where you are going with the Austrian diesel, but I had one and they stick to the rails very well.

 

Address your track  

Yes I'm pretty sure it is an issue related to that piece of track but I cannot see why a loco with six wheels picking up current manages not to be touching any live rails, something must be holding them off the track.

I can't determine what is so special about these prairies that it affects them and nothing else?

 

 

[melmerby]

Just had another close look at exactly where the locos were stalling. I could see they both stopped dead right on a rail joint with an insulated rail joiner.

I couldn't see anything wrong, the joint was pretty level and the gap was small.

So I ran my finger along the rail and could feel something sticking up but couldn't actually see anything, so I got in real close and then spotted a tiny (very tiny) sliver of clear plastic sticking out of the insulated joiner.

A quick trim with some fine cutters and all is well.

 

Both Prairies now negotiate the pointwork without stalling - hooray! This tiny piece of plastic must have been lifting the whole of one side off the rails.

 

But why, O why are they so touchy? Looks like they need a bit of vertical play added!

BTW the flywheel appears to be next to useless as there was no momentum at the point of contact loss, the locos stopped dead.

 

[MikeParkin65]

10 minutes ago, melmerby said:

The pony trucks are floppy, that was an early mod I did to the first one. So they aren't the cause.

 

Yes I'm pretty sure it is an issue related to that piece of track but I cannot see why a loco with six wheels picking up current manages not to be touching any live rails, something must be holding them off the track.

I can't determine what is so special about these prairies that it affects them and nothing else?

 

 

Are you running DCC or analogue? Just wondering if its DCC (and depending how your frogs are switched) whether the length of the live coupled wheelbase is causing an issue. 

[melmerby]

1 hour ago, MikeParkin65 said:

Are you running DCC or analogue? Just wondering if its DCC (and depending how your frogs are switched) whether the length of the live coupled wheelbase is causing an issue. 

It's DCC using the switches in the Tortoise motors to switch the frogs. All the rails are correctly fed and are live if they need to be.

I don't think there is a problem there as the praries ran through many other points simlarly configured without hesitation.

I could see when the locos reached the problem rail joiner the current drawn instantly dropped to zero.

[The Johnster]

21 hours ago, Butler Henderson said:

The main problem with the Airfix ones was the current draw of the motor could exceed the current capacity of the springs in the sprung plungers.

 

The 2721 actually uses the 1978 Jinty Chassis, plastic keeper plate with brake blocks and wheels/axles drop in place rather than the axle being pushed through the chassis block.

Yes, but the axle spacing of that chassis was set by the original R52 Jinty, which in turn was set by the coupling rods from the Rovex Black Princess, in a move to standardise components and cut costs.  Early Rovex/Triang were good at this. with the Princesss, Jinty/3F/'08', 3MT, and the 'Transcontinental' Hiawatha, Prairie, and Baltic all using common components, very efficient no doubt in terms of production but not amenable to scale modelling, but then again scale modelling was not the primary intention any more that it was for HD.  The feeling was, with more than a little justification, that scale models would not be able to run on the set track curvature.  Triang and Trix made no bones about this, but Hornby Dublo had BRSMB pretensions despite their hopelessly shortened pacifics and 'Deltic', every bit as 'bad' as anything Rovex ever did...

 

Rovex were pretty good at plastic moulding, and some surprisingly accurate models appeared that, with a bit of working up, stand the test of time well enough.  I am currently working up a Southern Rly. bogie luggave van with a Roxey kit, and it scales out to the drawing provided by Roxey spot on.  Other scale or at least reasonably close to scale models from this period include the Mugatroyd's bogie chlorine tank wagon, and the bogie well; 'also rans' might be the cattle wagon, GW toad, LNER 16ton toad,  horse box, and the dropside steel open. 

 

All stood too high of course, and the chassis were 'of their time', but some of those early models were pretty close.  The finishes and printing let them down a bit, but they were a big improvement on the concurrent tinplate Hornby Dublo or Trix equivalents.  There was a sea change about 1960, with Rovex Triang using a tension lock coupling that would be recognisable to us today, and HD abandoning die cast locos and tinplate stock in favour of plastic or at least part plastic stock and ntroducing a 2-rail range; Trix followed suit fairly quickly but adopted their odd 3.8mm/foot scale.  Some of HD's goods stock from that time are sitll with us the body toolings at least, from Dapol.

 

Mea culpa if I failed to make this clear; the original 2721 used a generic chassis that it shared with the concurrent Jinty, '08', J83, E1, and any other 0-6-0 that they were producing at this time, and this chassis was completely retooled from but can be genetically regarded as a direct development of the original R52 Jinty chassis, with an axle spacing suitable for a Rovex Black Princesses' coupling rods.

 

 

 

 

[The Johnster]

20 hours ago, tomparryharry said:

Sorry folks, but I'll return to my earlier post. The point I was making is that the Hornby chassis is currently 'all wrong'. That we know;  everybody and his god  know. What I was driving at is persuading Hornby to make a better model, pure & simple. Listing the faults won't help here one iota. In fact, it'll probably go against anyone trying to see, or achieve, a decent RTR model of an early-era pannier. 

 

Grumbling about 'this is wrong, and that is wrong' does no-one a favour.  Instead, try saying:- "You can improve it by doing..."

 

There will be nothing, if a manufacturer gets a hostile response.  

Mild rant over.

Ian.

And point made and accepted, Ian.

[tomparryharry]

1 hour ago, melmerby said:

Just had another close look at exactly where the locos were stalling. I could see they both stopped dead right on a rail joint with an insulated rail joiner.

I couldn't see anything wrong, the joint was pretty level and the gap was small.

So I ran my finger along the rail and could feel something sticking up but couldn't actually see anything, so I got in real close and then spotted a tiny (very tiny) sliver of clear plastic sticking out of the insulated joiner.

A quick trim with some fine cutters and all is well.

 

Both Prairies now negotiate the pointwork without stalling - hooray! This tiny piece of plastic must have been lifting the whole of one side off the rails.

 

But why, O why are they so touchy? Looks like they need a bit of vertical play added!

BTW the flywheel appears to be next to useless as there was no momentum at the point of contact loss, the locos stopped dead.

 

 

Nice one Keith.

[The Johnster]

1 hour ago, melmerby said:

BTW the flywheel appears to be next to useless as there was no momentum at the point of contact loss, the locos stopped dead.

 

I'm glad you have solved your problem; it's amazing how the tiniest bit of crud in the wrong place can mess things up and be difficult to trace.  If there is no (or insufficient) vertical play in the drivers then the loco tips sideways and one side's driving wheels are out of contact with the railhead, and a stall is the result at low speed, because low speed is where a flywheel is least effective.  Flywheels are nice to look at, not bad as ballast, and give an impression of 'proper engineering' to a chassis, but are in fact more or less pointless in slow running 4mm models.  They might be of some actual use if they were geared, like a 'push'n'go' toy friction drive.  The purposee of a flywheel is to store mechanical energy and release it 'on the overrun', and a geared flywhell would be more effective at this job, slowing accelleration and giving a realistic overrun which would aid smooth stops, starts, and slow running, but need a different driving technique in DC, with a bit more thinking ahead for fine positioning and shunting.  I condone this in principle.

[melmerby]

As a point of interest here is the comparison between the 2 Prairies and the dinky Austrian shunter before finding the problem: