Lima/Bachmann 94xx conversion.

[The Johnster]

Part the first, in which Johnster attempts to put the Lima body on to the Bachmann chassis to see what needs to be done to make it fit, and finds more things to do...

 

Took the chassis out of my Bachmann 57xx temporarily and offered it up to the Lima body.  There are two parts to the body, a boiler/cab/bunker assembly and a lower bodywork part, the footplate, splashers, smokebox saddle and 'skirts', with the buffer beams.  This latter piece feels a little flimsy when you separate it, and I am proposing to at least attempt to do the work with the two pieces attached.

 

The first obvious obstruction is a cross piece in the lower bodywork part to brace it; this has been cut out.  Now the Baccy chassis can be offered.  What seems to be needed is removal of the plastic backing the skirt, and a part of the smokebox saddle to clear the Baccy weight and DCC board.   The skirt has a sort of ledge which should represent the point to which plastic has to be removed; I will probably fit the slitting disc into the minidrill later this afternoon and start work, but I can't let myself get too involved as SWMBO needs to be taken out and wined and dined later as part of one of those anniversaries that they find so important (8 months),

 

The rather silly and vestigial front sandboxes will be cut off, and I will have to put a new smokebox dart on the shopping list.  The rh bunker steps need to filed and filled.  I will probably do the first coat of black acrylic once this is done.  

 

Thank you again for the very informative input, gentlemen!

[The Johnster]

Part the second, in which an encouraged Johnster reckon's he's made some progress...

 

I have viciously attacked the lower bodywork with a big slitting disc, and have cut away the plastic level with the 'base', I supposed you'd call it, of the shelf or step in it that back the original model's boiler skirts (at the back of it) and the splashers, balance pipe, and other bits and bobs under there.  This has cleared enough width for the Baccy chassis to sit happily in there; I could have got away with a little less width in the event, but I have about ½mm clearance which isn't bad for a guestimate.  But the front end of this moulding has to be cut away as well to clear the ballast weight of the chassis, which is also the housing for the DCC chip and has a recess in it for the wires to sit safely in out of the way.

 

This meant changing the disc for a smaller one to get in between the footplate frame, and cutting two slits about 5mm into the smokebox saddle level with the previous cut, if that makes sense.  A cross cut between the ends, and out it comes, with a bit of persuasion involving brutality with a pair of pliers.  This made an awful mess, but a few minutes cleaning up with the craft knife has removed it from the model and broadcast it all over the bedroom carpet, so I have to do a bit of hoovering that is nothing to do with Class 50 diesels!

 

Now I have to cut the rear of the smokebox barrel where it protrudes inside the front of the tanks, if protruding inside is a proper way to express the situation.  This is a bit more of a problem; I have made a start with a horizantal cut at the top and two vertical ones up from the bottom to meet it, but the minidrill cannot be inserted into this hole more than the depth allowed by it's shaft, so a bit of fiddly work with burrs and that sort of thing will be needed.  

 

I have 'try fitted' the lower body on the chassis, and it rests on the front part with the remains of the smokebox saddle at the right height (checked by the buffers of an adjoining vehicle, with the remains of the splashers fairly accurately in line with the driving wheels.  The splashers are of course cut down from the rear, and the flanges are visible behind them in a way they should not be, but I am not too bothered about this for the moment.  

 

Touching wood at the moment (stop that at the back, you bad people), this looks as if my main worries about fouling things when the body is placed over the chassis are unfounded!  Even on the try fit, it looks light years better than the Lima abomination that sat under it yesterday.  Enough work for today, more tomorrow or more likely Sunday now.

 

I need to be thinking about ballast, as the Lima weight (best bit of their chassis!) will not fit anywhere now, and about how to open up the front cylinder cover, which was not fitted on the BR 'production series' locos, which to my mind had a more 'Hawkworth Plate Frame' look as a result.  We'll see.

 

Put in an eBay bid for a Baccy 57xx earlier; maybe my loco will have it's own chassis soon!

Edited June 15, 2018 by The Johnster

[The Johnster]

Bid successful; my 94xx now has working bits and should be able to run soon!

 

It's not been a bad day...

[Il Grifone]

The snag with this project is that Lima in their wisdom/ignorance fiddled with the cab dimensions to make it fit their (awful) J50 chassis. This has an extra 3mm* between the centre and rear axles, which puts the rear splashers in the wrong place with the correct chassis.

 

* Correct for a J50 which has  a 7' 3" + 9' 0" wheelbase for some strange reason.

[tomparryharry]

Hi Folks, whilst we're on the subject....

 

Does anyone do etches for the cab widows for a 94xx/pannier, please? I am also working the Lima 94xx upgrade, and the cab is just awful.

 

Many thanks,

 

Ian.

[The Johnster]

If you mean the rear cab window coal bars, I have to agree completely and without reservation; they'd have done better to leave them off so we could make our own.  They are actually the correct profile for the outside on the inside of the cab, which suggests a bit of a senior moment during the planning stage of the model.  This and cylinder front cover which is only correct for the first 10 locos and no use whatever to me are probably the most irredeemable features of the whole Lima body.  Almost everything else is fixable with a little effort.  One can only hope somebody does an etch. that will rescue myself and Ian from our predicament

 

I would be fairly certain the Bachmann, when it arrives, will be much better!

[TheSignalEngineer]

Hi Folks, whilst we're on the subject....

 

Does anyone do etches for the cab widows for a 94xx/pannier, please? I am also working the Lima 94xx upgrade, and the cab is just awful.

 

Many thanks,

 

Ian.

I've got some old Craftsman ones which I will measure to see of they are right. They are E9 late type Panmier window guards Edited June 16, 2018 by TheSignalEngineer

[chris45lsw]

The snag with this project is that Lima in their wisdom/ignorance fiddled with the cab dimensions to make it fit their (awful) J50 chassis. This has an extra 3mm* between the centre and rear axles, which puts the rear splashers in the wrong place with the correct chassis.

 

* Correct for a J50 which has  a 7' 3" + 9' 0" wheelbase for some strange reason.

Because 7ft 3in + 9ft 0in is a common GNR/LNER wheelbase.

 

Chris KT

[Il Grifone]

Because 7ft 3in + 9ft 0in is a common GNR/LNER wheelbase.

 

Chris KT

 

Yes, but why such a large disparity? Other companies found no need for such an extreme.

[tomparryharry]

Yes, but why such a large disparity? Other companies found no need for such an extreme.

The space between the centre driving wheels, and the rear set of drivers, is down to the space needed for the locomotive firebox and the inside valve gear. The rotational mass of the valve gear (eccentrics, with the connecting rods, take up a significant space lengthwise. Add to that the locomotive firebox area, and it's starting to get a bit cramped there.

 

In some cases, it's no bad thing to have a slightly longer coupled wheelbase, as in certain circumstances, it provided a smoother ride in real life. An example would be the 15xx pannier, versus the 94xx model. The 15xx waggles all over the place, whereas the 94xx is a somewhat smoother ride.

 

Cheers,

 

Ian.

[tomparryharry]

If you mean the rear cab window coal bars, I have to agree completely and without reservation; they'd have done better to leave them off so we could make our own.  They are actually the correct profile for the outside on the inside of the cab, which suggests a bit of a senior moment during the planning stage of the model.  This and cylinder front cover which is only correct for the first 10 locos and no use whatever to me are probably the most irredeemable features of the whole Lima body.  Almost everything else is fixable with a little effort.  One can only hope somebody does an etch. that will rescue myself and Ian from our predicament

 

I would be fairly certain the Bachmann, when it arrives, will be much better!

The internet is your (our) friend. I've done a spot of digging about, and found reference to these on the Mainly Trains website. However, Comet/Wizard are still making these, reference MT226. I'll be ordering some very soon.

 

Cheers,

 

Ian.

[The Johnster]

Another potential problem has occurred to me, that of the rear coupler.  The try fit shows that the loco body can be sat reasonably well on the chassis with the leading and centre drivers aligned 'close enough for jazz' to the splashers, but that the bunker extends off the back a bit; not measured it but about 4mm.  This will mean that the tension lock on the new chassis will not stick out at the back far enough, and I do not know if the new chassis has NEMs.  No problem if it does, as a 'long' coupler will sort the problem out, but if it has the older screw fit type...

 

Work is basically on hold until the new chassis turns up, as I am less prone to losing fixing screws from the 57xx's one if it is screwed to it's proper body.  I am not scared of taking bodies off, but work to the principle that it should be done as little as possible to a well running loco.  I have tentatively started on the body, cutting away the right hand bunker steps leaving holes to be filled, and removing moulded handrails from that side and the one on the cab roof which also shouldn't be there.  Lima presumably only had a drawing for one side of the loco, but managed to get the pipework under the tank at the firebox end right; quite a lot about this model doesn't make sense but that's all part of the fun...  

 

But I might give it a coat of paint tomorrow so that it looks more like a BR built loco; this is self aimed psychology to encourage me to keep the pace up!

[34theletterbetweenB&D]

...Correct for a J50 which has  a 7' 3" + 9' 0" wheelbase for some strange reason.

 The GNR had been a Crewe 'Ramsbottom' wb 0-6-0 line, 7'3"+ 8'3". (The other tribe at Derby were 8'+8'6". Between them these two sets of wheelbase dimensions were all over the UK railway's loco works like a rash.) The GNR deviated relatively late in its existence when Ivatt was CME, his largest 0-6-0 getting 7'3"+9', and this change lived on under Gresley on the GNR and then the LNER, 'adjusted' slightly to 7'6"+8'9", last seen in new designs on the Thompson B1 and Peppercorn K1.

[TheSignalEngineer]

Another potential problem has occurred to me, that of the rear coupler.  The try fit shows that the loco body can be sat reasonably well on the chassis with the leading and centre drivers aligned 'close enough for jazz' to the splashers, but that the bunker extends off the back a bit; not measured it but about 4mm.  This will mean that the tension lock on the new chassis will not stick out at the back far enough, and I do not know if the new chassis has NEMs.  No problem if it does, as a 'long' coupler will sort the problem out, but if it has the older screw fit type...

 

My new 57xx chassis has NEM fittings. The front one doesn't seem too bad, I think the bar will be about in line with the buffers but I haven't tried against the replacement ones yet. The back one is definietly short but I have fitted a cab/bunker floor to screw the chassis to so will probably mount some Parkside sockets on that.

[chris45lsw]

Yes, but why such a large disparity? Other companies found no need for such an extreme.

Not unknown on other railways.  Some examples - Dugald Drummond's LSWR 700 class was 7ft 6in + 9ft 0in as was his brother, Peter's HR 0-6-0.  And Peter's G&SWR 0-6-0 was 8ft 1in + 9ft 0in.  Ex GER locos - J17 & J19: 8ft 10in  + 8ft 10in / J20: 8ft 10in + 10ft 0in.  I imagine the J20 had the longest wb of any British 0-6-0?  NBR J37: 7ft 9in + 9ft 2in. J38/J39: 8ft 0in + 9ft 0in. 

 

Chris KT

[terry.ecmr]

Having had a re-read of the Pannier Paper regarding the 94xx, a small but important detail springs to mind. It appears that the cylinder front upper cover on the later 94xx is mostly omitted. It certainly seems that the first 10 had these covers, but later locomotives largely worked without.

 

I'd hazard a little guess that Bachmann are in a quandary over this. "Do we, or don't we?" If you're making the first ones, they'll need the cylinder covers(and, if you're making the later years, omitting the covers anyway) but the addition either way very firmly places the locomotive into a different timescale. Problems indeed!

 

With all of the renewed interest in the class, it's time I got my finger out, and finally finish off my model....

 

Happy modelling!

 

Ian.

Good point.

 

I did the conversion on my Lima body.

[timbowilts]

Hi Folks, whilst we're on the subject....Does anyone do etches for the cab widows for a 94xx/pannier, please? I am also working the Lima 94xx upgrade, and the cab is just awful.Many thanks,Ian.

Wizard Models have taken over the old Mainly Trains range, that includes a pannier window etched fret. I have one for my multiple 94xx projects, three of them! One SEF and two Lima bodies on replacement chassis of varoius trypes.

 

Tim T

[tomparryharry]

Wizard Models have taken over the old Mainly Trains range, that includes a pannier window etched fret. I have one for my multiple 94xx projects, three of them! One SEF and two Lima bodies on replacement chassis of varoius trypes.

 

Tim T

Nice one Tim, I'm putting in an order tomorrow. I'd like to get most, if not all of the bits before I start.

[The Johnster]

My new 57xx chassis has NEM fittings. The front one doesn't seem too bad, I think the bar will be about in line with the buffers but I haven't tried against the replacement ones yet. The back one is definietly short but I have fitted a cab/bunker floor to screw the chassis to so will probably mount some Parkside sockets on that.

 

Thank you for this.  I will have to make up some sort of cab/bunker floor in any case to hide the view of the trackbed if you are looking downwards through the cab cutouts, and since there will be a backhead with the new chassis I may well cut out the sliding shutters to show it better, so presumably I will be able to mount a coupling socket on that.  I will also have to make up some sort of bunker front detail to go in there, and the sensible thing to do is probably to mount that on the new floor and offer the thing up to the body as a single assembly.

 

Painting the body later.

[The Johnster]

Wizard Models have taken over the old Mainly Trains range, that includes a pannier window etched fret. I have one for my multiple 94xx projects, three of them! One SEF and two Lima bodies on replacement chassis of varoius trypes.

 

Tim T

I shall be following this up; many thanks Tim T!  It will make a very big difference to the rear view of the finished model.

[The Johnster]

Not unknown on other railways.  Some examples - Dugald Drummond's LSWR 700 class was 7ft 6in + 9ft 0in as was his brother, Peter's HR 0-6-0.  And Peter's G&SWR 0-6-0 was 8ft 1in + 9ft 0in.  Ex GER locos - J17 & J19: 8ft 10in  + 8ft 10in / J20: 8ft 10in + 10ft 0in.  I imagine the J20 had the longest wb of any British 0-6-0?  NBR J37: 7ft 9in + 9ft 2in. J38/J39: 8ft 0in + 9ft 0in. 

 

Chris KT

This goes back to very early days, when, following Robert Stephenson's stated concept that a locomotive should have 6 wheels, and unpowered leading and trailing wheels tended to be of a larger diameter in the quest for smooth riding, designers placed the firebox, which perforce must protrude downwards between the middle and trailing axles, ahead of the trailing axle, which ran beneath the cab.  This axle spacing determined the maximum size and to some extent the shape of the firebox.  The spacing between the front and middle axles similarly determined the space available for the connecting rods, eccentrics, and valve gear, and the height of the leading axle imposed a limit on the size and shape of the cylinders.  Any design of this sort has to make a compromise between the overall length of the wheelbase; too long and it won't go round curves, to short and riding at speed is compromised.

 

The Stephenson 6 wheeler in various forms was a standard for many years, the only game in town apart from Cromptons, in 0-6-0, 2-4-0, 0-4-2, and 2-2-2 forms, and was still putting in good service on new pannier tank designs after WW2, admittedly ones which had their roots in the Victorian era.  Fast passenger work had overwhelmed it by the 1890s, when 4-4-0s became the standard, the firebox still sitting ahead of the trailing axle, but it was not for another decade that 8-coupled freight locos began to appear, and the advantage of trailing pony trucks with smaller diameter wheels enabled Atlantics on fast passenger work.  4-6-0s, basically enlarged 4-4-0s with much bigger boilers, appeared at around this time as well, but 0-6-0 Victorian 'Goods' locos were still being designed 30 years later.

 

British loco designers seem to have been unwilling to depart from a concept that they knew worked, and the catalogue of failures amongst those who tried did not encourage them much.  But this small c conservatism held things back for much of the 20th century, and the 94xx's only modern concession is a taper boiler, hardly cutting edge in 1947!

Edited June 17, 2018 by The Johnster

[The Johnster]

Thank you for this.  I will have to make up some sort of cab/bunker floor in any case to hide the view of the trackbed if you are looking downwards through the cab cutouts, and since there will be a backhead with the new chassis I may well cut out the sliding shutters to show it better, so presumably I will be able to mount a coupling socket on that.  I will also have to make up some sort of bunker front detail to go in there, and the sensible thing to do is probably to mount that on the new floor and offer the thing up to the body as a single assembly.

 

Painting the body later.

 

No I'm not; I've run out of black paint.  Manana...

[Il Grifone]

Not unknown on other railways.  Some examples - Dugald Drummond's LSWR 700 class was 7ft 6in + 9ft 0in as was his brother, Peter's HR 0-6-0.  And Peter's G&SWR 0-6-0 was 8ft 1in + 9ft 0in.  Ex GER locos - J17 & J19: 8ft 10in  + 8ft 10in / J20: 8ft 10in + 10ft 0in.  I imagine the J20 had the longest wb of any British 0-6-0?  NBR J37: 7ft 9in + 9ft 2in. J38/J39: 8ft 0in + 9ft 0in. 

 

Chris KT

 

Agreed, but none is as extreme as 7' 3" + 9' 0".

 

The story goes that the management considered that the 57xx/8750 design looked old fashioned', so the 15xx/94xx were designed with a 'modern' taper boiler at the expense of increased axle loading. Sense was seen with the 16xx. (If it ain't broke. don't fix it!)

 

 

No I'm not; I've run out of black paint.  Manana...

 

Ah, mañana (aka domani, demain, morgen etc.) - my favourite time for doing things....

 

Sorry for any errors in the above. Windows decided to do one of its updates in the middle of it!

Edited June 18, 2018 by Il Grifone

[tomparryharry]

x.   

Edited June 23, 2018 by tomparryharry

[Steamport Southport]

 

 

The story goes that the management considered that the 57xx/8750 design looked old fashioned', so the 15xx/94xx were designed with a 'modern' taper boiler at the expense of increased axle loading. Sense was seen with the 16xx. (If it ain't broke. don't fix it!)

 

 

 

I think that's a bit of an urban myth as they were still building 8750s at the same time.

 

It was more the fact they were built to replace all the antiquated or non standard South Wales 0-6-2Ts many of which already had a similar boiler.

 

 

 

Jason