Bachmann 94xx

[mdvle]

4 hours ago, The Johnster said:

The Rapido Stirling Single has a ‘single motor split drive’ mechanism, as does the Hattons/DJM 14xx, so that the loco is effectively an 0-6-0, or 0-4+2-0; the Whyte notation doesn’t really cope with this sort of thing!  UIC B-A, perhaps, if the prototype is B-1...

 

Not a fair comparison given the price of the Stirling and the compromised reputation of the 14xx model.  Bachmann have done very well to bring the 1P on at the price level they are quoting IMHO.  But I’m hard to convince on the subject of traction tyres on the basis of many years of bitter experience and of quantum improvements in the performance of any loco they are removed from.

 

Not entirely relevant, but Rapido's first North American steam loco (Royal Hudson) comes with traction tires.

 

It is somewhat easy to make a steam loco that doesn't pull much without traction tires, but at some point the compromise between no traction tires and the inability to pull a train leans towards the necessity of giving in to traction tires.

[Ozexpatriate]

Is there any evidence to suggest that the Bachmann 94xx will have traction tyres?  That would surprise me for an 0-6-0PT.

 

If not, any discussion of traction tyres here is moot.

 

I've seen many US steam locomotives that come with optional traction tyres to haul prototypical length trains of more than a dozen coaches. The driving wheels on these locomotives are geared to the motor.

 

The issue I have with UK models with traction tyres is with models dating back to the 1980s with tender drives. On these models, traction tyres are necessary to make the driving wheels connecting rods rotate. These are abomination. Without the traction tyres the sticking friction can make the driving wheels slide along the tracks without rotating. Secondarily there are issues with disintegration.

[34theletterbetweenB&D]

On ‎01‎/‎02‎/‎2020 at 19:35, The Johnster said:

...a problem that could be better dealt with by powered rear bogies (on 0-4-4T) ...

Since we have the Rapido Stirling single model demonstrating the concept of driving two different diameter wheels successfully, this is clearly possible.

15 hours ago, adb968008 said:

...if it were using gears then it would be a rigid chassis, more of an 0-8-0 in terms of handling... not much use for corners unless one of the drivers was flangeless ?

That's unduly pessimistic. Several long wheelbase rigid chassis with eight flanged wheels models are in successful use on R2. And if absolutely necessary, then rather than an all gear coupled rigid chassis a low profile shaft drive to the rear bogie allowing a little more chassis flexibility is possible, and could be concealed below the top of the cab doors. This would bump the cost up however.

 

I would still prefer for 0-4-4T that the designer focus on solid weight using the densest material available forward of the rear coupled axle centre, motor immediately behind the gearbox on the rear coupled axle, lightweight tackle like the decoder socket location in the bunker. Put maximum weight forward, and a light spring on the bogie pivot for stability, and a well balanced loco that will pull decently is simply obtained. No need for a traction tyre on a driven wheel which is the optimum location for pick up, always a concern on small and relatively short wheelbase locos.

 

Even without this optimal layout, Hornby's M7 (which has the motor and decoder socket right above the coupled wheelbase, thereby forgoing about 100g of extra mass in the ideal location!) will start and pull realistically at slow speed 11 of Bach's mk1s on level track. (That's near 2kg of train weight, the expected performance from what I estimated as 19g force traction. With the optimal interior layout, I reckon 30g force is possible, and that's in the same ballpark as a typical small 0-6-0T, which is more than good enough for most modeller's purposes.)

[PMP]

2 hours ago, Ozexpatriate said:

Is there any evidence to suggest that the Bachmann 94xx will have traction tyres?  

 

None whatsoever. The only person talking about them being fitted is the Johnster. 

 

Why? NFI..

[woodenhead]

2 minutes ago, PMP said:

None whatsoever. The only person talking about them being fitted is the Johnster. 

 

Why? NFI..

Trying to guess the F 

[Steamport Southport]

21 minutes ago, PMP said:

None whatsoever. The only person talking about them being fitted is the Johnster. 

 

Why? NFI..

 

It wasn't him that brought the subject up though.

 

 

 

Jason

[PMP]

18 minutes ago, Steamport Southport said:

 

It wasn't him that brought the subject up though.

 

 

 

Jason

This thread is about the 94xx. See below regarding specific reference to the 94xx and traction tyres by the johnster. No one else.

[Steamport Southport]

But he still didn't bring the subject up as proven in that post.

 

 

 

Jason

[Legend]

Yes I just quoted what Tony Wright said on DVD , which did surprise me , that the 94XX has a Coreless Motor . Traction tyres never mentioned .   So as I used to say to my Mum 50 years ago " It wasn'ae me!"

[PMP]

6 hours ago, Steamport Southport said:

But he still didn't bring the subject up as proven in that post.

 

 

 

Jason

So who first brought the subject of the 94xx and traction tyres then? Please quote the post.

[cctransuk]

1 hour ago, PMP said:

So who first brought the subject of the 94xx and traction tyres then? Please quote the post.

 

I was the first to mention traction tyres, but not in relation to then 94XX; it was in a reference to the MR 2P which had been mentioned in the same post as the 94XX and coreless motors.

 

So now can we stop the 'he said it first' bickering?

 

Regards,

John Isherwood.

[PMP]

36 minutes ago, cctransuk said:

 

I was the first to mention traction tyres, but not in relation to then 94XX; it was in a reference to the MR 2P which had been mentioned in the same post as the 94XX and coreless motors.

 

So now can we stop the 'he said it first' bickering?

 

Regards,

John Isherwood.

I’m well aware of that John. It appears others haven’t actually read what you wrote.

[ndg910]

Where is Johnster when we need him? I think we need some good old fashioned 94xx delay posts instead of posts about traction tyres. Sarcasm mode off.....

[cctransuk]

1 hour ago, PMP said:

I’m well aware of that John. It appears others haven’t actually read what you wrote.

 

With respect, PMP, you're making a mountain out of a molehill.

 

Somewhat out of context, I pointed out that the 2P was to have traction tyres.

 

I believe that 'the Johnster' said that he hoped that the 94XX would not have them - (note; nothing about it having them).

 

So what's the problem? No-one has said that the 94XX would have traction tyres.

 

End of story - nothing to see here - let it go!!!

 

Regards,

John Isherwood.

[PMP]

Well John the EP has been available to inspect at many shows and with detailed images in this very thread recently from Phil Parker, with no indication of traction tyres whatsoever. 

 

A previous poster asked was there any evidence of traction tyres and I supplied the answer and the source of the ‘confusion’ to put it politely. I was then told I was incorrect. Which was incorrect.  If of course you hadn’t originally mentioned that traction tyres were being used on another unrelated model to this thread, we wouldn’t be having this discussion, would we?

[atom3624]

I suppose traction tyres would give it the pulling power it requires, but being a tank locomotive 0-6-0, surely it's going to have power collection problems on DC power, if not DCC with 'stay alive'?

 

A decent cast chassis, metal running plate, even body or tanks would give it more weight which would help considerably.

 

Al.

[lofty1966]

1 hour ago, ndg910 said:

Where is Johnster when we need him?

Is there EVER a need for a Johnster?

[adb968008]

Oh la la !

 

time for a glass of wine !

 

just dont use a rubber coaster to put your glass on, my coaster has good enough adhesion made from wood.

 

Now I do have a Hornby pannier with traction tyres....

Nooooooooo dont go there.

 

Edited February 4, 2020 by adb968008

[Paul.Uni]

RRP has increased by £5 to £129.95

[The Stationmaster]

12 minutes ago, Paul.Uni said:

RRP has increased by £5 to £129.95

So knock off the 15% discount and it will cost c.£110 on release.  The £129.95 is however pretty much ballpark for a really good 0-6-0T.  The Model Rail 16XX, which will be a smashing job I'm sure, is £134.10 for subscribers and £149 for other buyers althought it is a commission which can have an upward impact on price.   

[gwrrob]

33 minutes ago, Paul.Uni said:

RRP has increased by £5 to £129.95

 

Or 15 sheets more than their 8750 class pannier's RRP.

[Paul.Uni]

32 minutes ago, gwrrob said:

 

Or 15 sheets more than their 8750 class pannier's RRP.

10 more actually as the RRP for the 57xx & 8750 has also gone up by £5.

[Graham456]

41 minutes ago, gwrrob said:

 

Or 15 sheets more than their 8750 class pannier's RRP.

As we have been waisting space typeing about non exestiant traction tyres, can I point out that sheets only come in  denominations of five for a good few years now, bearing that in mind are you suggesting that it is £75 pounds dearer ?

ducks and signs off forum for a while!

[adb968008]

If it werent for the mass discount events a few years after release, models would be a better interest rate than current accounts as a hedge against inflation.

[The Johnster]

On 04/02/2020 at 22:12, lofty1966 said:

Is there EVER a need for a Johnster?

Probably not.  But I stands me round, know some good yarns, and am mostly harmless, kind to animals and old ladies, and clean up the mess if I’ve made it.  

 

5 hours ago, Paul.Uni said:

RRP has increased by £5 to £129.95

About in line with expectation IMHO.  I was prepared to pay £124.99, another fiver’s not gonna make a difference.  It’ll be the most I’ve ever spent on a single model railway item, by a very large margin!