motorising plastic kit prairie.

[The Johnster]

I would not nowadays attempt to motorise a plastic kit large prairie as there are plenty of cheap Airfix GMR or Hornby previous tooling RTR ones on the 'Bay, and while they are inferior to the current Hornby model, they run well enough and the Hornby tooled body makes a tolerable 'layout' model.  Back in the day, the biodiversity of RTR models was much more restricted than it is now, so it was sort of inevitable that, if one wanted a large prairie, one thought about how to achieve this from the Airfix (previously Kitmaster, subsequntly Dapol, and now Kitmaster again) plastic kit.

 

The kit range enabled us to use RTR running chassis, especially the Black Princess which was already a bit passe by the mid 60s, my teens, and we cobbled up running large prairies, cut the Black Princesses down into Jubilees or Black 5s, put Airfix Biggin Hills on our Triang Winston Churchill chassis because they were 'better' , used HD Stanier 8F chassis with bits of the prairie kit and the CoT boiler to make 42xx, made 56xx out of it with Jinty chassis, and so on. 

 

None of this was proper modelling; the locos had major issues with scale, detail, which axle the pistons drove in some cases, fragile motion (we lubricated it with pencil graphite but it was always a weakness).  But it was, quite by accident and not intentionally, a good grounding in solving some of the problems we'd have when we 'graduated' to whitemetal and eventually brass kits.  We started replacing wheels and axles with Romfords, then gears, learned that ballast was vital and the more you could get on board the better (Biggin Hill proved quite successful in this respect).  Mostly, though. we learned that we were not as good as the RTR manufacturers and that kitbashing of this sort was a blind alley, even if it was good training,  We did it to achieve representations of the models we wanted that the RTR people didn't produce, though their ranges were improving.  But at glacial speeds...

 

Even now, I look at the axle spacing of models and wonder what else besides the body they come with can be put on that chassis.  Some of the locos on my own layout are a bit crude (Hornby 2721, Triang Dock Authority) and it is my instinct to look for ways of improving them rather than wait for a retooling.  I still cut models about to achieve the loco I want to represent, and have no qualms about tacking kits, including chassis.  The reason I don't do this very much is that in many cases the models I want are available RTR, and are pretty good.  In 1965 there were no RTR panniers, small prairies, 56xx, 42xx, and the only large prairie was the Graham Farish 81xx; there was a 94xx from this firm as well, but they were expensive and would not run on setrack curves.  This is why the whitemetal kits were so successful, and why they are struggling now. 

 

 

[hayfield]

There is one exception to this advice, that is for those who prefer "Retro" modelling. Also motorising kits (Simplus ?) still come to light on eBay and are eagerly snapped up. But as we both have said, the model trade is very different today than it was 60/70 years ago. As stated there are numerous possibilities available now with so many used items widely available to all 

[melmerby]

51 minutes ago, The Johnster said:

I would not nowadays attempt to motorise a plastic kit large prairie as there are plenty of cheap Airfix GMR or Hornby previous tooling RTR ones on the 'Bay, and while they are inferior to the current Hornby model, they run well enough and the Hornby tooled body makes a tolerable 'layout' model.

IMHO the previous Hornby Prairie is a better bet than the original Airfix one.

It had a re-tooled chassis with a decent can motor driving the centre axle through a gear tower, later ones also have a DCC socket.

It's weak point was that it re-used the Airfix designed wheels, cylinders & motion and poor front truck (the rear is a bit better).

Also the cab is fairly full of die-cast chassis block which is good for adhesion but not if you want a decent cab interior.

 

I have two of them and they are better load haulers than the current model (which I also have two of) and still look reasonable.

Airfix got the look right all those years ago (same with the Dean Goods, shame about the pathetic tender drive) and with Hornby's superior finish still look OK.

[andyman7]

14 minutes ago, hayfield said:

There is one exception to this advice, that is for those who prefer "Retro" modelling. Also motorising kits (Simplus ?) still come to light on eBay and are eagerly snapped up. But as we both have said, the model trade is very different today than it was 60/70 years ago. As stated there are numerous possibilities available now with so many used items widely available to all 

Yes! Thanks for saying this.

So much is available RTR to standards that exceed that of professional lit building capabilities of 30+ years ago, so for practical purposes I can't disagree with the options for anyone who wants a scale Prairie. But there is no harm and plenty of enjoyment to be had tinkering with retro modelling, and Dapol kits are cheap practice. I definitely have an addiction to buying up cheap scratch and kit building efforts from the 60 and 70s and playing around with them for fun (see seperate MTK thread for the rabbit holes this can send you down). 

[Jeff Smith]

Midland - have sent you PM regarding Branchlines Dapol conversion kits.

[hayfield]

2 hours ago, andyman7 said:

. I definitely have an addiction to buying up cheap scratch and kit building efforts from the 60 and 70s and playing around with them for fun (see seperate MTK thread for the rabbit holes this can send you down). 

 

Now this is a completely different matter. Firstly you are correct in that these kits can be rebuilt sometimes with additional details and if required improve/modify/replace the chassis. and made into lovely models. Old Wills kits lend themselves as Southeastern Finecast are happy to sell replacement parts, and now sell etched chassis for most of the kits

 

Secondly they can be very useful for parts (I believe some call it farming) or even the basis of a kitbash. Quite often I buy one for the wheels and or motor and resell the kit itself. And can be very cheap.

[33C]

Some interesting comments above, e.g. "retro modelling". I like that phrase! I personally love the clunky, old stuff, it's got real metal in it for a start that doesn't disintegrate! Triang solid wheels give a loco "weight" to the eye, the lack of detail is just that, detail! Add it if you want... I like a toy loco to do a job, pull stuff, and look good enough doing it and the fact that some of the motive power i'm using was contemporary with the real thing, and has lasted longer than the prototype gives me a buzz.....also, you can't kill a princess but you can turn her/it into a frog (SNCF?)!! I fancy my next project may be something Indian, an XC 4-6-2 has always appealed after reading Colin Garrett's books.

[5050]

I remember BITD when the Kitmaster Prairie was the latest thing, the old Model Railway Constructor ran an article on motorising one using a Hornby Dublo chassis - but I'm sure it wasn't the R1.  It might even have been a rewheeled Duchess.

 

These type of articles appeared almost every month back then, in line with the almost monthly releases of the various kits. The West Country kit was motorised with a Hornby Dublo A4 chassis.

 

Airfix magazine also ran a series of articles on kitbashing all sorts of GWR locos from Prairies and City of Truro kits.

[Dave John]

Well it was proper modelling Johnster, it's how we learned. I made a really bad job of a couple, some southern thing and a 2.6.0 of some sort way back. 

 

I look round here, modern rtr is very good and the best kit and scratchbuilders are impressive beyond anything we could have imagined. But that isn't any help to someone who is starting out and wants to sit down and actually make something, as many experienced builders have pointed out. I hope that basic kits and cheap bodgeable chassis are available for the future , it is how so many of us started. 

[Jeff Smith]

Here lies the conundrum - if you build a simple rigid chassis and it runs badly do you give up on the assumption that if you can't do that you can't do anything....or do you recognize that the design is poor and move on to a more complex well designed one that stands a better chance of success, assuming you are up to the challenge of building it!

 

My first kit was a K's Pannier, built as per the parts supplied in the kit with rigid stamped brass chassis, it ran, but did not do well on the exhibition circuit.  It later got a Percy P4 one which transformed it - of course P4 helps......

[PatB]

Bottom line is, if you just want a Large Prairie there are cheaper, easier routes to a better model than the Dapol kit will produce. However, if you want to develop skills and gain some satisfaction on the cheap, there are things you can usefully do with it, especially if combined with assorted bits from sources contemporary with the original kit. 

 

The second approach is a perfectly valid reason to do something, IMHO. However, I personally tend to find it a bit discouraging to put in time, effort and money to produce something inferior to a model I could have bought off the shelf for less. The antidote to this is, of course, to build things unavailable r-t-r. The County tank idea sounds attractive. Maybe kitbash some appropriate stock from Triang clerestory and/or Ratio bodies, and have a GWR passenger train that you simply cannot buy off the shelf. 

[hayfield]

9 hours ago, Jeff Smith said:

Here lies the conundrum - if you build a simple rigid chassis and it runs badly do you give up on the assumption that if you can't do that you can't do anything....or do you recognize that the design is poor and move on to a more complex well designed one that stands a better chance of success, assuming you are up to the challenge of building it!

 

My first kit was a K's Pannier, built as per the parts supplied in the kit with rigid stamped brass chassis, it ran, but did not do well on the exhibition circuit.  It later got a Percy P4 one which transformed it - of course P4 helps......

 

 

Jeff

 

I think you may be confusing a badly produced chassis kit with a well designed chassis kit

 

A well designed simple rigid chassis can be easily made to run well by a novice builder. I recently built a Southeastern Finecast 0-6-0 (FC200) etched brass chassis as a rolling chassis to test track, it was very easy to build and runs extremely freely. In fact something I can easily recommend to a beginner

 

I have a few K's locos using K's chassis working well in EM gauge and one in P4 all rigid, these all have been built with new wheels, most with new motors and gears (even used a High Level gear box). Most of K's chassis issues all start from being badly made cheap items. The simpler chassis (0-4-0 & 0-6-0) being far easier to build than the more complicated ones

 

For me I could argue building a compensated chassis may be slightly harder than a rigid one.

[Jeff Smith]

An absolutely rigid chassis, ie with no up or down movement of the wheels will probably perform less well through points than a RTR.  Even if built absolutely square it will most times only have two wheels in firm contact with the track for current pick up.  RTR chassis have deliberately built in slop to try to improve this situation.

 

To my mind compensation improves OO current collection so is advantageous.  It is frequently used in O-16.5 loco kits which are basically OO.

[hayfield]

Jeff

 

Agreed, but unless I am mistaken my reply was in relation to novice builders with limited abilities moving on from RTR chassis. Therefore it was directed at those with limited experience and abilities. Not at experienced modellers

 

As I said, I have a SEF etched brass rigid  0-6-0 EM gauge un-motorised test (for building turnouts) chassis which glides through common crossings (its basically an 0-4-0 as the center wheels are 0.5mm higher to compensate for unevenness in the track).

 

For the novice builder an average built rigid chassis will work far better than a badly built compensated/sprung chassis.

[melmerby]

4 hours ago, Jeff Smith said:

An absolutely rigid chassis, ie with no up or down movement of the wheels will probably perform less well through points than a RTR.  Even if built absolutely square it will most times only have two wheels in firm contact with the track for current pick up.  RTR chassis have deliberately built in slop to try to improve this situation.

 

To my mind compensation improves OO current collection so is advantageous.  It is frequently used in O-16.5 loco kits which are basically OO.

Three surely, as a tripod is the minimal stable configuration, two wheels must tip one way or other until a third makes contact.

[Jeff Smith]

48 minutes ago, melmerby said:

Three surely, as a tripod is the minimal stable configuration, two wheels must tip one way or other until a third makes contact.

Yes, well spotted.  The point I was trying to make was that potentially only one wheel on one side is collecting current.

[Jeff Smith]

3 hours ago, hayfield said:

Jeff

 

Agreed, but unless I am mistaken my reply was in relation to novice builders with limited abilities moving on from RTR chassis. Therefore it was directed at those with limited experience and abilities. Not at experienced modellers

 

As I said, I have a SEF etched brass rigid  0-6-0 EM gauge un-motorised test (for building turnouts) chassis which glides through common crossings (its basically an 0-4-0 as the center wheels are 0.5mm higher to compensate for unevenness in the track).

 

For the novice builder an average built rigid chassis will work far better than a badly built compensated/sprung chassis.

John, we may be looking at this from different perspectives.

 

a) a chassis that mechanically runs smoothly with no binding

b) a chassis that has good continuity and does not stall going through points or over uneven track.

 

Ideally both should be satisfied!

[hayfield]

32 minutes ago, Jeff Smith said:

John, we may be looking at this from different perspectives.

 

a) a chassis that mechanically runs smoothly with no binding

b) a chassis that has good continuity and does not stall going through points or over uneven track.

 

Ideally both should be satisfied!

 

Jeff

 

This could be said of a Hornby jinty with clean wheels on a clean track reasonably well laid. Even my old Hornby Dublo 3 rail locos ran through their points without stalling and as an 8 year old no one ever told me about cleaning wheels or track.

 

Agreed for ultra slow operation having all wheels incontact with the track at all times is very desirable, I cannot argue with you on this one and I am not6

 

The point I was making was in the context of a novice builder starting out building their first chassis. 

[melmerby]

If I can make a slow running chassis, anyone with a modicom of skill can.

Herewith my 1854 Wills body on a Comet Chassis with Mashima motor, Branchlines gearbox & Markits wheels.

As a test I ran it through a Peco code 75 Electrofrog 3 way and double slip.

Fitted with a Lenz Silver Mini decoder

 

 

[sagaguy]

I`ve not motorised a Kitmaster/Dapol Prairie but i have married a Dapol BoB onto a modified Dublo Barnstaple chassis,92 Squadron recently.

I`m just in the process of fitting a Dapol Deltic body to an extended Dublo Co Co chassis.

 

                    Ray.

Edited November 2, 2020 by sagaguy

[PatB]

I tend to think that rigid and compensated chassis offer different challenges. A compensated chassis has more, often fiddly, bits to stick on, and so greater opportunity for assembly errors. However, the compensation will just as happily compensate (within reason) for distortion as it will for track irregularities. A rigid chassis must be built accurately square to work acceptably, even if it only comprises a single fold-up unit and some axle bushes. Depending on the skills and facilities available to the builder either may offer the better compromise for the individual. I've built (simple) examples of both, and feel that  basic compensation offers me a greater chance of success (although it's marginal). I would not, however, want to go through the fiddle of making and adjusting individually sprung axle boxes. Kudos to those who do, but I'd fear for my sanity. 

[Jeff Smith]

The Comet sprung hornblocks used in my 43xx thread below did not require any adjustment and were ludicrously easy to install.

[hayfield]

9 hours ago, melmerby said:

If I can make a slow running chassis, anyone with a modicom of skill can.

Herewith my 1854 Wills body on a Comet Chassis with Mashima motor, Branchlines gearbox & Markits wheels.

As a test I ran it through a Peco code 75 Electrofrog 3 way and double slip.

Fitted with a Lenz Silver Mini decoder

 

 

 

 

From what I could see the track was more at fault than the loco, also is not DCC more susceptible to loss of power than DC, On the plus side you have used quality components in the chassis build. I would assume a flywheel and or stay alive accessory would improve matters, as would larger radius hand built track, but where do you stop?

 

[Jeff Smith]

Keith, you didn't say whether it was compensated or rigid.

[melmerby]

15 minutes ago, Jeff Smith said:

Keith, you didn't say whether it was compensated or rigid.

Rigid, you can probably see it bumping over the gaps at the frogs
The problem I have found is that the kits I have completed aren't really fast enough. (Ive done a Comet 43XX as well plus a couple of M&Ls, mostly complete).

That model in the video has a scale top speed of a little over 30mph, although it is fairly smooth, if somewhat noisy

 

IMO The motor/gearbox combo could be better, the motor is hardly rotating at the speed in the video, there is a certain amount of cogging.

It's a Mashima 1220 (external brush, can motor), could do with being more powerful & higher revving.