Excellent loco drawings

[Ravenser]

One problem is that we are stumbling round in a fog of opinion, taking people's gut feel as authoritative, in the absence of any facts:

 

(emphasis added by me)

a)

I think they're quite accurate

 

B)

I would suggest that the Bachmann models are pretty much spot on

 

c)

It probably is

 

a) What evidence do we have that the Railnews 150 /142/ 143 drawings are meant to be scale? Has anyone ever checked them in any way? (I would quite like to have some factual foundation on which to base an opinion). At the moment we're stumbling around making fact-free guesses as to their validity

 

B) What checks have been made on the accuracy of any of the Bachmann models, by anyone? Only a few leading dimensions are in print , and I've checked those. But are we sure that windows are the right height and width, and set at the right spacing , both in terms of the gaps between the windows , and their height /position up the side. These are fairly key questions when modelling a coach - which is what a DMU effectively is - and normally you'd use a drawing to compare. RTR manufacturers have certainly been known to play fast and loose in these sort of areas (the Triang Southern EMU was scale length, It just had one compartment too few........), and when you consider that Dapol managed to leave the chassis off their 155 and extend the whole side about a foot lower than it should have been, and it passed for a decade and a half without attracting comment , it hardly inspires confidence in RTR DMU models or the ability of modellers to pick up their problems (I know there was an occasional remark that the model wasn't too hot, but I don't remember people specifically pointing out there was a pretty major error in a fundamental dimension. Just contrast this with the furore over the tumblehome and waist panelling on the Hornby Gresleys. Everyone in the hobby seemed able to quote chapter and verse on that). Are the side profiles/ tumblehomes ok? Anyone out there have opinions and/or evidence?

 

I'm increasingly getting a sick suspicion that nobody has ever bothered to check the accuracy of RTR second generation DMUs against anything

 

Classes 101, 105, 108 , 114 are a different matter - we have drawings in Goldings A Pictorial Record of BR DMUs to use for comparison, and from the absence of comments I take it that Golding's drawings are accepted as pretty reliable

 

c) We seem to have arrived at the position on PDH drawings of DMUs that they may be right or they may be wrong , but we don't really know and have no basis for deciding , and we don't know which bits on which classes are wrong.

 

Since they appear to be the only readily available detailed info on the later units , this is not very satisfactory ......

 

Pugsley

You can tell that the Hornby 142 isn't quite right from photographs, IIRC there's something with the front end but I can't remember what exactly, but it affects the positioning of the numbers relative to the windscreens.

 

It looks to me from photos that there are in fact deep pillars behind the front windows - that the inside of the cab front may be vertical , but the outside face and glazing is at an angle, and that by the bottom of the cab front windows the glazing may be recessed by about a foot from the inside face of the cab front, like the windows in some medieval castle . How you modify the Hornby model to represent this I'm not sure. Perhaps someone who's actually been in the cab of a 142 would like to comment whether the windowsare indeed recessed at an angle in this way

 

And for the avoidance of doubt, it seems that both the PDH Peak drawings and Marsden/Fenns drawing of the 44 have problems, though possibly not in the same areas.

[Dave47549]

.

[Guest jim s-w]

Sometimes you dont need to measure anything to know its wrong - for example I copied a marsden/fen drawing of a class 40 once and the cabs were completely different to each other. Anyone who knows anything about producing something from a drawing will tell you that you never scale from a drawing - only ever scale from the dimensions on the drawing.

 

and when you consider that Dapol managed to leave the chassis off their 155 and extend the whole side about a foot lower than it should have been, and it passed for a decade and a half without attracting comment , it hardly inspires confidence in RTR DMU models or the ability of modellers to pick up their problems (I know there was an occasional remark that the model wasn't too hot, but I don't remember people specifically pointing out there was a pretty major error in a fundamental dimension.

 

A-hem!

 

 

 

Cheers

 

Jim

[Ravenser]

Jim S-W

Anyone who knows anything about producing something from a drawing will tell you that you never scale from a drawing - only ever scale from the dimensions on the drawing

 

I know scaling off drawings is not best practice , and for engineering purposes, where fits and tolerances are involved, a complete no-no. However in this situation we don't have much in the way of published dimensions - typically just length and width out of a Platform 5 book, and it's not made clear exactly what those dimensions have been measured over.

 

The alternatives therefore become:

 

- scale off a scale drawing, recognising that there's a risk of some error

- try to work out some kind of dimension by scaling off a photo that won't be at right angles , attempting to correct somehow for perspective , which means trying to estimate the mid point then average the front half and the back half , and the whole thing may be subject to lens flare at the extremities... This isn't a recipe for accuracy

- gaze at the model and pray that Barwell/Margate/Vicenza got it right....

 

None of these approaches are ideal, but scaling off a scale drawing seems a lot better than the alternatives

 

I take it that the photo is of a Hornby 153 next to a Dapol/Hornby 155? The difference really leaps out and hits you when you see the two side by side - but it was only when I had a Hornby 153 to compare that I realised just what was wrong with the 155 sides . I'm not sure any of it is strictly right and the windows aren't in fact the same size shape , and position in the side. (Somehow I need to patch up a W.Yorks 155 so it passes muster near a pair of 153s Not sure how I manage that... Flushglazing a155 is a major job in itself.)

 

Dave47549 - thanks for your photos. Your last shot shows exactly the issue with the cab windows - in fact its worse still, because the bottom sills of the front windows are not only about 18" deep , they slope downward at about a 45 degree angle - notice all the debris lying on them. Basically on the Hornby model all that white stuff behind the black area on the cab front just isn't there..... And it changes the look of the cab front appriaciably. I just don't know how to rework the inside of the Hornby cab front to get even an approximation of this

[Guest jim s-w]

 

I take it that the photo is of a Hornby 153 next to a Dapol/Hornby 155? The difference really leaps out and hits you when you see the two side by side - but it was only when I had a Hornby 153 to compare that I realised just what was wrong with the 155 sides .

 

Nope - Both Dapol - one before and one after I have fiddled with it!

 

Cheers

 

Jim

[pete_mcfarlane]

On the subject of class 142s, back in the mists of time (September 1986 rings a bell) the Railway Modeller ran a competition to scratchbuild on of these new fangled British Rail contraptions. It included detail photos and an Ian Beattie drawing which may be useful.

[Ravenser]

On the subject of class 142s, back in the mists of time (September 1986 rings a bell) the Railway Modeller ran a competition to scratchbuild on of these new fangled British Rail contraptions. It included detail photos and an Ian Beattie drawing which may be useful.

 

Thanks for that . I even have the issue. Very useful indeed . Drawing stated to be prepared off originals supplied by Leyland Bus , so it ought to be one of his more reliable efforts, and there are plenty of piccies

I want my 142s in early condition anyway, for the 1985-90 period , so it helps that the drawings show the units "as was" (there's not much else you can do when one's in Skipper livery and the other in Provincial - in due course one of Charlie's 144s can cover the circa 2000 slot). The drawing is also reproduced for N scale

 

Only one dimension is given on the drawing (wheelbase) but there is a scale of feet shown on the drawing

 

It will be interesting to do cross comparison s between the Ian Beattie drawing and the Railnews one - this should pin down just how precise the Railnews material is meant to be

 

I realise reference to a 20 year old out of print book and a 25 year old magazine may have modellers in their teens and twenties gnashing their teeth (I remember my feelings as a youthful modeller when reading "drawings can be found in MRN for April 1959" or "it is motorised using the old Kemilway kit long out of production, from my scrap box"). However people give away old modelling magazines just to be rid of them , so this issue may turn up, and clubs with a library may well have a copy

[Guest stuartp]

The only reference material available to me is some drawings in the reprint of Railnews Stockspot, which come from a semi-official industry source and appear to be scale side elevations

 

The Stockspot drawings were by David Gibbons who was a Technical Illustrator (I think) for the BRB, and who also did the illustrations for Traincrew Manuals and the like. He should therefore have been working from original source material, presumably the works drawings, but his work was by neccessity illustrative rather than technical, if that makes sense. By that I mean that his drawings were intended to be interpreted by drivers and guards, not people experienced in reading technical drawings, so tend to be more pictorial than your average GA drawing.

[finelines]

They were printed in a 2 volume paperback.

 

Rogrt

[Ravenser]

Some findings in the case of the class 142:

 

Length:

P5 book gives 15.66m , which in 4mm equates to 205.5mm

Ian Beattie/RM drawing, length of bodyshell excluding gangways 197mm

Railnews/ Ian Allan drawing, length of bodyshell 197mm

Hornby Pacer 193.5mm

 

The figure in the P5 book would appear from the Beattie drawing to be the length over couplers - a real pitfall for the unwary

 

The agreement of both drawings , based on different but very good industry sources, suggests they are right , and the Hornby Pacer is nearly a scale foot too short

 

Width:

P5 book gives 2.60m which in 4mm equates to 37.75mm

Ian Beattie/RM drawing 36mm

Railnews No end view drawing

Hornby model 35.5mm

 

I suspect that the Hormby model is a whisker too narrow, and just possibly the P5 dimension is width over handrails (shades of the tubbyduff - clearances/projections would be an issue that industry figures would have to take into account)

 

But at this stage, no certainty on the width.

 

Height (from bottom of bodyshell to top of roof - not roof pod) :

P5 book no dimensions

Beattie/RM drawing 36.5mm

Railnews drawing 37.4mm (after conversion on calculator)

Hornby model 35mm

 

The missing 1mm-2mm is in the roof itself - ie a flatter profile. Photographic evidence suggests that the Hornby model is indeed too flat roofed and the cab front destination boxes are too squashed, though again there is no certainty at this point about the correct value

 

 

The cab front profile is an issue. Hornby , Ian Beattie/RM and photographic evidence shows a flat slab cabfront, with a slight lip around the base , matching the lower bodyside. The Railnews drawing shows the lower cab front sloping back slightly without a lip - effectively it shows the class 141 cab front profile. I suspect it may have been prepared before class 142 entered traffic. The cab front is a detachable moulding on the Hornby model and this is about 1.5mm thinner than the corresponding part of the Beattie/RM drawing, which looks more bulbous around the lower cab front

 

The main body from the rear of the doors to the back edge of the bodyshell at the gangwayed end is 2mm short. compared to the Beattie drawing. Of this,1mm is lost between the last window and the end of the bodyshell. The other 1mm is distributed across the 8 body sections - effectively 0.125mm per section

 

It might be possible for the dedicated to address these issues - assuming the Beattie drawing is right. It would require replacement scratchbuilt cabfronts to be made - the missing material is at the front , not the back of the Hornby moulding - but the cab front is a seperate moulding anyway . It might also be possible to graft on a layer of 40 thou plasticard on part of the gangwayed ends , but this would necessitate a repaint

 

(And reverting to the original subject - PDH's drawings , it gives some basis for assessing how accurate their 142 drawing may be and identifying any issues)

[martin1]

hello,i have used pdh for a few years now and have found them exerlent drawings,does anyone know if he is still in trading? ive sent for some drawings over a month ago but have not been able to contact him,either by phone or e mail so don't even know if my letter arrived safely.i do hope he is still trading as there are few people willimng to do as many vairied drawings as pdh.

[billbedford]

- scale off a scale drawing, recognising that there's a risk of some error

- try to work out some kind of dimension by scaling off a photo that won't be at right angles , attempting to correct somehow for perspective , which means trying to estimate the mid point then average the front half and the back half , and the whole thing may be subject to lens flare at the extremities... This isn't a recipe for accuracy

 

The machine still exist, so there is really nothing  to stop you taking your own measurements and photos to produce drawings that will satisfy yourself.

[t-b-g]

The only accurate drawings are those that are full dimensioned.

 

Having been drawn by humans, even they can (and sometimes do) contain errors.

[berwicksfinest]

I have just read this topic !!

 

I understand that Railnews at some point did a stockspot one month featuring  Class 141/142/143/144, the following month they done Class 150/1, 150/2 155 156.

 

Does any kindly person still have a copy of these ?? I could get at copy of ??

 

I have tried Railnews themselves to no avail

 

Many thanks   John

[Ravenser]

I have just read this topic !!

 

I understand that Railnews at some point did a stockspot one month featuring  Class 141/142/143/144, the following month they done Class 150/1, 150/2 155 156.

 

Does any kindly person still have a copy of these ?? I could get at copy of ??

 

I have tried Railnews themselves to no avail

 

Many thanks   John

 

 

They were reprinted in a book - BR Equipment 2  (Drawings from Railnews Stockspot) See post 23 in this thread for the ISBN of the first edition, and page references

 

The book might be available via your local library, on request: requests through Library services used to go right up to the British Library , which is a copyright library and has a legal right to a copy of every book published.

 

Copies might be available from specialist second hand book sellers like Robert Humm - at a price. Or a copy might turn up in the bottom shelf of the second hand books in the shop at some preserved railway, or someone's club stand at a show....  

[berwicksfinest]

They were reprinted in a book - BR Equipment 2  (Drawings from Railnews Stockspot) See post 23 in this thread for the ISBN of the first edition, and page references

 

The book might be available via your local library, on request: requests through Library services used to go right up to the British Library , which is a copyright library and has a legal right to a copy of every book published.

 

Copies might be available from specialist second hand book sellers like Robert Humm - at a price. Or a copy might turn up in the bottom shelf of the second hand books in the shop at some preserved railway, or someone's club stand at a show....  

Hi Ravenser

 

I did used to have both the Equipment books 1 and 2. Unforunately they didn't cover exacty the stockspot produced.

 

From my faded memory I believe the Class 141 was just a visual representation rather than the detailed in Railnews, The 142 and 143 were better although smaller and over 2 pages and I don't believe the 144 was shown.

Sprinter wise again I believe the 150/1 and 150/2 were more representations rather than drawings and I believe there was no class 155 but the Class 156 was faithfully reproduced.

 

I did have the Railnews pages but I have lost them in the mists of time and would love to get another copy or the Railnews issues themselves

 

But many thanks for the thoughts

 

John

[charliepetty]

Be careful as his DMU & EMU drawing have many silly errors, they are a good guide, but not the Holy Grail.    Charlie